How to use a 125mm angle grinder hook and loop backing pad on a Bosch 5 inch random orbit sander

If you receive my newsletter, you’ll know I wrote a rave review of the Bosch GEX 125-1 AE (the 120V version is coded ROS20VSC).

It’s a fantastic random orbit sander. I use it for sanding skimboards and cupboards.

But the hooked backing plate wore out too quickly.

I sanded half a cupboard at full speed with a 40 grit sanding disc, and the hooks on the backing plate disappeared.

I contacted Bosch about this, asking them whether this was standard for their backing plates.

Bosch replied, saying that it happens sometimes, especially with coarse grit sanding discs, and that they’d send me a free backing plate replacement.

I was elated at their response, since these backing plates are expensive.

In the meantime I needed to sand down a cupboard and skimboards.

Cheap backing plate

I bought a cheap hook and loop sanding plate for a 125mm angle grinder from a local hardware store. Compared to the Bosch backing plate it costs mere pennies.

But it can’t mount to the Bosch ROS. It’s as different from the Bosch backing plate as seawater is from cola.

The Bosch’s backing plate locates onto the sander via four pins and is secured to the sander with four screws.

The cheap backing plate secures to a 125mm angle grinder via 14mm thread.


I’d have to make an adaptor.

So I drew up a concept.

Here’s a screenshot of the adaptor drawn up in Sketchup.

Sketchup screenshot of adaptor to use angle grinder hook and loop backing plate on Bosch ROS20VSC random orbit sander
Sketchup screenshot of adaptor to use angle grinder hook and loop backing plate on Bosch ROS20VSC random orbit sander.

I’m not sure if this adaptor will work for other random orbit sanders. Some ROS machines use three screws for the backing plate, while others, like the Bosch, use four.

Also, take note that the angle grinder hook and loop backing plate does NOT take a 125mm (5 inches) sanding disc, but a 115mm (4.5 inches).

How to attach it

I follow three steps to use my backing plate adaptor.

  1. I secure the 14mm socket cap screw to the adaptor with a washer and lock nut.
    • I use a 12mm Allen key and 22mm spanner (wrench, if you’re in North America).
  2. I screw the adaptor to the Bosch random orbit sander with four button head cap screws.
    • The Bosch GEX 125-1 AE uses 4mm thread.
    • I use a 2.5mm Allen key.
  3. I screw the angle grinder backing plate to the 14mm bolt.

Wood, plastic or metal?

I contemplated making the adaptor from wood, but realised it wouldn’t hold up against the random orbit sander’s vibration. There’s not much meat on the adaptor, so it would fall apart.

I thought about having it made from mild steel, but realised that it might be too heavy for the machine.

I would have been happy with plastic, but the man who made the adaptor gave me a good price on aluminium.

I got a happy medium between the worries of wood and malady of metal.

Why not DIY?

Designing the adaptor took me back to my toolmaker days, when I worked on lathes, milling machines and other machinery. (I’m tempted to say, “those were the days!”)

The right machinery destroys limits. Not having the right machinery hamstrings. Limitations call for innovation or delegation.

I don’t have a milling machine and a lathe, both of which were required for making the adaptor. Delegation was my only option.

Does it work?

Sanding plywood with the Bosch GEX 125-1 AE with the adaptor for an angle grinder Velcro sanding plate
Sanding plywood with the Bosch GEX 125-1 AE with an adaptor for an angle grinder sanding plate.

Sadly, it doesn’t work well.

Using the adaptor places the sanding surface much farther from the machine. This makes the machine unstable.

In fact, I need to use two hands to keep the machine stable. I also have to drop the ROS’ speed, otherwise the machine vibrates too much.

I don’t advocate using this sort of adaptor as a permanent replacement. I had it made to help me out of a sticky situation.

When I need to sand down cupboards and don’t have a Bosch backing plate, or can’t find one at a local store, this tool will help me out of a tight spot.

But it’s best to use a Bosch ROS20VSC original backing plate.

Check this short video to see how the Bosch GEX 125-1 AE (ROS20VSC) works with the custom adaptor.

Excellent machine

Despite the hiccup with the Bosch sander’s backing plate, I give the tool two thumbs up.

It doesn’t remove material as fast as a belt sander, but it’s safer. It’s also quicker than an orbital sander, yet gives the same finish.

But the outstanding feature is the Bosch’s apathy towards sanding direction. Whereas a belt sander, orbital sander and hand sanding require sanding with the grain, the random orbit sander puts no restriction on your sanding direction. It doesn’t scratch your project, no matter how you sand it.

I suspect the problem with the backing plate is not restricted to Bosch sanders; it’s one of the drawbacks of using a random orbit sander with a hook and loop system.

In future I’ll start with a 60 or 80 grit sanding disc, instead of 40. That should increase the backing plate’s life.

Read my review of the Bosch random orbit sander and get yourself one if you’re in the market for less stressful sanding.

Bosch GEX 125-1 AE (ROS20VSC)

I bought a secondhand orbital sander for sanding skimboards and furniture.

It’s OK for light sanding, but it’s terrible for heavy material removal, and it’s a chore to change sanding paper. And sometimes the paper vibrates off the tool, while other times it tears.

I needed something that would make sanding easier and wouldn’t devour sandpaper.

Research led me to the 125mm (5 inch) Bosch GEX 125-1 AE random orbit sander (the 220V version). (The ROS20VSC is the same machine, but in 120V format.)

Here’s what I think of it…

Ease of use

The Bosch GEX 125-1 AE is a breeze to use.

Stick a Velcro sanding disc onto the sanding plate (line up the eight dust holes), press a button and start sanding.

Want to go smoother on the finish? Rip off the current sanding disc and stick a finer grit disc onto it. Takes five seconds.

Don’t stress about following the grain, like you need to with a belt sander, orbital sander or sanding block. Throw the random orbit sander in any direction. It doesn’t leave marks.

Like the Dremel Saw Max I reviewed, the Bosch ROS is a plug-and-play machine.

Surface quality

The Bosch GEX 125-1 AE leaves a surface as smooth as you want it to be.

The sanding machine is one part of a system that gives you a smooth surface. Grit is another crucial component, as well as time spent on each grit.

As far as the machine goes, it does its part in giving you a great finish.


The Bosch GEX 125-1 AE is fast.

Changing a disc takes a moment or two.

A smooth finish is yours in two ticks.

Need to sand a radius into a work-piece? Use a coarse grit and watch it form in a minute.


The Bosch GEX 125-1 AE comes with a removable dust collector.

It doesn’t catch every spec, but it does a fine job of keeping dust to a minimum.


Because the Bosch GEX 125-1 AE comes with variable speed, you have control over sanding velocity.

This is a brilliant feature, because higher speeds coupled with uneven surfaces cause tool-walk. This is when the tool (in this case, a sander) bucks your direction in favour of its own course. This could cause scratches, which require more sanding.

Replaceable sanding plate

Your sanding plate worn through from too much sanding? Don’t chuck your machine into the bin.

Simply change out the old sanding plate for a new one and you’re good to go.

You’ll need a T20 torx key or flathead screwdriver for loosening the sanding plate screws.

In the box

The Bosch GEX 125-1 AE box contains the following items:

  • Bosch GEX 125-1 AE random orbit sander.
  • Bosch 80 grit random orbit sanding disc (1 of).
  • Instruction manual.

How to use

Follow three steps to use the Bosch random orbit sander:

  1. Plug it into an electrical outlet.
  2. Stick a hook and loop sanding disc onto the sanding plate.
  3. Switch on the machine and start sanding.

How to sand

Don’t apply too much pressure when you sand with the Bosch ROS. Rely on its weight to do most of the work. Your job is to guide the machine to where you want it to sand.

You needn’t worry about sanding direction. The Bosch GEX 125-1 AE is direction agnostic. It doesn’t leave marks, irrespective of which direction you sand your surface in. This is not the case with a belt sander, orbital sander or sanding disc, all of which leave scratch marks if you don’t sand with the grain.

If your surface is in a bad state, start with a rough grit sanding disc. I use a 40 grit on some jobs. It might be too heavy for the average sanding job, so perhaps start with an 80 grit. Work your way up from there. (Remember, the higher the grit number, the smoother the sanding paper.) I use 40, 60, 80, 120, 150, 220, 300 and 400 grit sanding paper. At the 400 mark the wood starts to reach a “smooth-as-butter” feel. If you wish, work it up to 600, perhaps beyond.

If your Bosch sander runs around on the job, drop the speed, or ramp it up, until you’re in control.

Sanding disc info

The Bosch ROS’ sanding plate is one half of a hook and loop system. It has eight holes. Let’s take a closer look.


The GEX 125-1 AE uses a Velcro (or hook and loop) system for gripping sanding discs.

This is an excellent system, because it allows for rapid change of sanding discs. Change sanding discs in seconds and get the job done in no time.

Closeup of the Bosch GEX 125-1 AE's hook and loop system
Closeup of the Bosch GEX 125-1 AE’s hook and loop system.


The Bosch ROS has eight holes in the sanding plate. These holes assist in dust extraction. So if you use sanding discs without holes, your random orbit sander won’t remove dust as well as it can.

Sanding disc range

There’s an overwhelming number of random orbit sanding disc manufacturers.

Tigershark stands out on Amazon. They make a range of 5 inch random orbit sanding discs with great ratings.

They make sanding discs from heavy duty latex paper coated with aluminium oxide. Their pads are designed to reduce edge tear and offer increased sharpness and durability.

You’ll get them in the following varieties:

  • 80 grit
  • 100 grit
  • 120 grit
  • 150 grit
  • 180 grit
  • 220 grit
  • 320 grit
  • 400 grit

Dustless sanding discs

Penrose makes sanding discs they claim are dustless.

I can’t vouch for the accuracy of their claim, since I’ve not tried their discs yet. But they’re available on Amazon.

Penrose PRO-Net DuraDiscs dustless sanding discs for random orbit sander
Penrose PRO-Net DuraDiscs dustless sanding discs for random orbit sander.

Dust collection

The Bosch GEX 125-1 AE comes with a filtered dust collector.

How to remove the dust collector

To remove the Bosch’s dust collector:

  1. Twist the dust collector off.
  2. Shake it out into a bin.
  3. Twist it back on.

Although tbe dust collector doesn’t eliminate dust, it does a fine job of reducing it.

As a test, I used it in my workroom, which is not made for this sort of work. There’s no special ventilation and I don’t have an extraction fan either. For the test, I left the windows closed too.

I used the following discs:

  • 40 grit
  • 60 grit
  • 80 grit
  • 120 grit
  • 150 grit
  • 320 grit
  • 400 grit
The discs I used for sanding in my work room. From left to right, 40 grit, 60 grit, 80 grit, 120 grit, 150 grit, 320 grit and 400 grit
The discs I used for sanding in my work room. From left to right, 40 grit, 60 grit, 80 grit, 120 grit, 150 grit, 320 grit and 400 grit.

Some of the discs don’t have holes, while one has only six holes. This is what I could find at my local store.

The Bosch didn’t kick up nearly as much dust as I expected, even with the hole-less discs.

Here are before and after pictures of my work table and the work-piece…

Do the holes help with dust extraction?


There’s a marked difference between the way the Bosch handles dust with discs containing holes, and discs without holes.

Inside the Bosch GEX 125-1 AE's dust collector, after sanding the scrap piece
Inside the Bosch GEX 125-1 AE’s dust collector, after sanding the scrap piece.

How to open the dust collector

To open the dust collector, release the clips and pop it open.


You can attach a vacuum nozzle to the Bosch GEX 125-1 AE, provided you have the right connector.

Or duct tape.

My vacuum cleaner nozzle doesn’t fit, since the attachment is the same size as the Bosch’s exhaust.

DIY vacuum attachment

If you have some perseverance lying around, make your own random orbit sander vacuum attachment.

My vacuum pipe tapers up from 30.7mm (1.2 inches).

The PVC pipe I used has an outside diameter of 40mm (1.57 inches) and an inside diameter of 36mm (1.42 inches).

Here’s what I used in the making of the adaptor:

  • Roll of duct tape.
  • Wooden dowel.
  • PVC pipe.

Tools I used for this:

Here’s how I did it, in six steps…

  1. I cut a piece of PVC pipe, 53mm (2.08 inches) long, using my dozuki saw.
    1. Make this as long as you want it.
    2. I smoothed the edges using metal files.
  2. I applied duct tape to the vacuum pipe, but in REVERSE.
    1. This gives the duct tape the same inside diameter as the pipe, so the pipe fits snugly into the duct tape.
    2. It must have an outside diameter equal to that of the inside diameter of the PVC adaptor.
  3. I stuck the newly formed duct tape tube into the piece of PVC pipe I cut.
  4. I rolled duct tape onto a wooden dowel.
    1. The dowel has a 19.4mm (0.76 inches) diameter.
      1. It needs to be 28mm (1.102 inches), which is what the Bosch ROS’ exhaust is.
  5. I rolled duct tape, in REVERSE, onto the duct tape on the dowel.
  6. I stuck the other end of the PVC adaptor over the reversed duct tape on the dowel.

That’s it. You now have a makeshift vacuum pipe adaptor for your random orbit sander. It should give you a few months of service before it falls apart.

Sanding tests

The Bosch GEX 125-1 AE excels at sanding wood. I tackled a number of projects with it, apart from the skimboards (for which I bought it).

I sanded 18mm shutterply for a corridor cupboard, for one.

I went from 40 grit through to 400 grit, giving the wood a finish so smooth it’ll make Kenny G jealous.

The left is unsanded, the right finished with the random orbit sander
The left is unsanded, the right finished with the random orbit sander.

I sanded one of the first skimboards I made, to re-coat it. This didn’t work well, the reason being that the board was coated with a few coats of primer and a number of top coats. It clogged up the sanding discs. In future I’ll use a chemical paint stripper or heat gun to remove thick paint.

However, once the paint was off, getting the board smooth took only a few minutes.


The ROS20VSC (120V) sells for $49 on Amazon.

Click here to buy the ROS20VSC now.

The GEX 125-1 AE (220V) sells for $112 on Amazon.

Click here to buy the GEX 125-1 AE now.

Sanding disc cost

You can buy a pack of six Bosch discs for a little over 10 dollars.

And although Bosch’s sanding discs are great, you’ll find a myriad of options on Amazon, many of which offer you fantastic sanding at a great price.

Difference between orbital sander and random orbit sander

They sound the same, but there’s a big difference between the two. Random orbit sanders are more expensive than orbital sanders, but they’re superior machines.

An orbital sander uses an orbital action to remove material.

A random orbit sander uses an orbital action, as well as a rotational action, to remove material.

It’s two for the price of one.

While an orbital sander works fine for finishing, the random orbit sander is superior, in that it allows you to do heavy material removal, as well as finishing.

Below is a picture of the Bosch OS50VC orbital sander. Although it’s a fantastic machine, it’s different from a random orbit sander.

Bosch OS50VC orbital sander
Bosch OS50VC orbital sander.


According to the Bosch FAQ section, Bosch blue products carry a twelve-months-from-date-of-purchase warranty.

If you register the tool online within four weeks of purchase, you extend the warranty to 36 months.

Registration is not available in all countries.

Technical specs

Technical specs for the Bosch GEX 125-1 AE random orbit sander.
Attachment methodHook and loop (Velcro)
Eccentricity1.25 mm (0,05 inches)
No-load speed7500 - 12000 rpm
Orbital stroke rate15000 - 24000 opm
Oscillating circuit diameter2.5 mm (0.09 inches)
Rated power input250 W
Sanding pad diameter125 mm (5 inches)
Uncertainty K1.5 m/s²
Vibration emission value ah5 m/s²
Weight1.3 kg (2.8 lbs)

Final thoughts

The Bosch GEX 125-1 AE (the 120V version is coded ROS20VSC) random orbit sander is an excellent tool for removing material and finishing wood.

It’s safe. A belt sander is fantastic for fast material removal. The problem is, it’ll remove your skin in no time too. It’s not a toy, especially if you’re not strong enough to handle it. The Bosch random orbit sander is much safer than a belt sander. I placed my hand on the sanding disc while it was running with a 40 grit disc, and it didn’t harm me.

It’s versatile. Although it doesn’t remove material as quickly as a belt sander, it’s much quicker than an orbital sander or a sanding block. It works on level surfaces, and I had no trouble shaping round corners.

It’s quick. Because the GEX’s sanding discs attach to the sander via Velcro (hook and loop fastening), you speed through different grits quicker than a Mustang racing a little old lady with a walking stick.

It’s easy. The discs are easy to remove. Also, you need not apply heavy pressure for it to work well. If you want to remove more material, faster, use a coarser grit. But don’t press too hard. Guide the tool and let it do the work for you. A normal orbital sander must be used in the direction of the grain. The Bosch random orbit sander is direction agnostic, meaning you can sand in any direction across your wooden project.

It gives a great finish. I needed a machine to handle rough and finish sanding. A beautiful, smooth finish is crucial (especially for my skimboards and my wife’s cupboards). The Bosch ROS gives me that.

I love the Bosch GEX 125-1 AE. I think you’ll like it too.

Dremel DSM20 Saw Max

I needed a tool for cutting plywood, so I bought a second hand jigsaw. It was a disaster. So I got the Dremel DSM20 Saw Max, hoping it would do a better job. Read on to find out if it did.

I bought a second hand jigsaw for cutting plywood for skimboards.

It’s a terrible tool for cutting thin sheets of wood, especially plywood, which it tears apart, even with a fine tooth blade. Using a jigsaw meant I had to cut a larger margin around the final part, which meant cutting it again after laminating.

That wouldn’t do.

I needed a unidirectional cutting tool that wouldn’t rip my plywood to pieces.

The ideal solution is a band-saw, but they’re expensive.

So my wife bought me a Dremel Saw Max for Christmas. (In some countries it’s coded SM20; in others, DSM20. It’s the same product.)

Here’s what I think of it…

Ease of use

The Saw Max is a joy to use.

Because of the adjustable foot, you set the cutting depth, place the Saw Max on the job and push.

At the front of the Saw Max is a small V cut into the plastic cover, called a line guide. Keep the line guide on the cutting line and you’ll cut straight.

To change the cutting disc, loosen the lock bolt (anti-clockwise) with the included Allen key, remove the old disc, insert a new disc, tighten and go.

To set the Saw Max’s height, loosen the screw for the depth scale on the side of the tool, set the blade to the depth of cut (shown on the Saw Max) and lock it in place.

All of this takes seconds to perform, making the Saw Max a breeze to use.

Cut quality

The Saw Max gives a beautiful, clean cut.

Because the jigsaw cuts with a bidirectional action, it shakes the plywood this way and that, causing the wood to splinter. It looks like a shark used the board as a toothpick.

The Saw Max blade runs in a single direction, which means there’s less chatter in thin material. This translates to a smoother cut.

One tool that cuts as nice as the Saw Max is the Gyokucho dozuki saw. It’s one of the best tools I’ve ever bought, but it has a different application. Even so, I recommend you get a dozuki too. (Read my review of the Gyokucho dozuki saw.)

The following pics show the difference in cut between a jigsaw, an angle grinder and the Saw Max.


A conventional angle grinder cuts towards you, if you hold it in your right hand with the blade parallel with your body, it’s bottom facing left.

Try cutting plywood with this setup and see how long before you’ve had enough of chewing on splinters and dust.

The Saw Max cuts away from you, which means you’re not feasting on wood chips and dust.

Furthermore, the Saw Max comes with a vacuum cleaner attachment, which makes working with it much cleaner than working with an angle grinder.


I split ten 4mm (0.16 inches) plywood sheets in four. The cross cut (1220mm / 48 inches) took 19 seconds, while the two rip cuts (total of 2440mm / 96 inches) took 15 seconds each.

That’s a total of 49 seconds per board (3660mm / 144 inches). That’s quick cutting.

There are tools that work quicker than that, but they won’t fit in a standard toolbox. Besides, the Saw Max is a joy to use.

Cutting disc info

The Saw Max comes with four discs: one for wood and PVC, the other three for metal.

However, there are five types of cutting discs in the range.

Cutting disc range

Saw Max cutting discs and their uses.
CodeDescriptionMaterialsBlade thicknessDiameter
DSM500Multi-purpose carbide cutting wheelDrywall / plasterboard / fiberboard / hardwood / laminates / plastic / plexiglass / plywood / softwood / vinyl1.9 mm (0.07 inches)77 mm (3 inches)
DSM510Metal and plastic cutting wheelAluminium / cast iron / copper / fiberboard / plastic / plexiglass / soft metal / vinyl1.27 mm (0.05 inches)
DSM520Masonry cutting wheelBrick / drywall / plasterboard
DSM540Diamond tile cutting wheelBrick / ceramic / drywall/plasterboard / floor tile / marble / porcelain / wall tile1.9 mm (0.07 inches)
DSM600Multi-purpose carbide flush cutting wheelDrywall / plasterboard / fiberboard / hardwood / laminates / plastic / plexiglass / plywood / softwood / vinyl

Cutting disc dimensions

Saw Max cutting disc dimensions.
Blade diameter77mm (3 inches)
Bore (centre hole) diameter11.1mm (7/16 inches)
ThicknessFrom 1.27mm (0.05 inches) to 1.9mm (0.07 inches).

The discs are small, compared to a baby angle grinder, which uses a cutting disc with a 115mm (4.5 inches) diameter.

But they’re large, compared to some of Dremel’s other discs, some of which have a diameter of 34mm (1.3 inches).

Generic cutting discs

Dremel’s cutting discs are expensive, so I emailed abrasive disc manufacturers, asking whether they make a three inch disc that’ll fit the Saw Max.

To give you an idea, here are some of the companies I emailed:

  • Blacksmith.
  • Bosch.
  • Diacut.
  • Draper.
  • Everett.
  • Fastflex.
  • Fischer.
  • Klingspor. (Danny Burnette at Klingspor USA gave exceptional service. He went out of his way to try and help me.)
  • Metabo.
  • Pferd.
  • Ridgid.
  • SIA.
  • Tork Craft (Vermont Sales).
  • Walter.

None of them has a disc that’ll fit the Saw Max.

You’re stuck using the Dremel brand, since no one makes a disc with an 11mm (7/16 inches) bore.

There are generics available for other Dremel machines, but not for the Saw Max (yet).

Keep an eye on two companies if you want to buy generic blades for your Saw Max.

One is Tork Craft, the other, Gyros Tools.

Neither have Saw Max blades yet, but I wouldn’t be surprised if they add it to their range.

Both of these companies make a range of cutting discs and accessories for Dremel’s other tools.

In the box

The Dremel DSM20 Saw Max box contains the following items:

  • Plastic carry case.
  • Dremel DSM20 Saw Max cutting tool.
  • PVC and wood cutting disc (DSM500).
  • Metal cutting disc (DSM510), (3 of).
  • Dust port adaptor.
  • Straight edge guide.
  • 2×4 cutting guide.
  • Allen Key.
  • Usage guide and other paperwork.

How to use

Follow these ten steps to start using the Saw Max:

  1. Remove the Saw Max from the carry case.
  2. Press and hold down the spindle lock.
  3. Loosen the lock bolt.
  4. Remove the outer washer.
  5. Place the cutting disc onto the inner washer, on the spindle.
    • Make sure it’s facing the right way.
  6. Place the outer washer onto the cutting disc.
  7. Screw in the lock bolt.
  8. Tighten the lock bolt.
  9. Adjust the cutting height.
  10. Cut.

How to use the straight edge guide

Follow these steps to attach the straight edge guide to your Saw Max:

  1. Locate the metal rod into the slot on the plastic guide.
  2. Lock the metal rod in place with the wing screw.
  3. Slide the assembled guide into the slot at the back of the Dremel Saw Max.
  4. Insert the square lock nut into the Dremel Saw Max.
  5. Insert the set screw into the lock nut.
  6. Lock the set screw in place.

The Saw Max laboured through the lumber with this rip cut. Don’t use it on thick planks.

How to use the 2×4 guide

This add-on is useless, to be honest. I’d rather draw lines on a 2×4 or cut without a guide, than go through the rigmarole of using this attachment.

Nevertheless, I thought I’d add it to the article to show you how it works.

You’re supposed to use a flush cut disc for cutting (DSM600) with this attachment, but I don’t have it. I used the standard wood cutting blade.

Cutting tests

I ran the Dremel through a few materials. Here’s how it fared…


I ordered ten 4mm (0.16 inches) sheets of plywood for making skimboards, but couldn’t get them cut at the factory on time. I could have arranged another company to cut them for me, but thought I’d try the Saw Max.

The sheets measure 2440mm x 1220mm (96 inches x 48 inches) and requires two cuts each (or three cuts, depending on how you do it), to split them into four.

That’s a total of 36,600 mm (1440.94 inches) of plywood.

It took me half an hour to measure and cut the sheets. Cutting took less than 50 seconds per sheet.


I couldn’t test the Saw Max on tiles, since I don’t have the DSM520 masonry wheel. But if the Saw Max’s wood cutting ability is anything to go by, it’ll run through tiles with ease.


I bought a 40mm PVC pipe with a 2mm wall thickness, and made two cuts down the length of the pipe.

I’ve used two other tools for the same job before: a dozuki saw and a baby grinder with a cutting disc.

Both of them worked fine, but the Saw Max lets me set the depth of cut, which means I don’t have to worry about cutting through the other side of the pipe.

The Saw Max had no trouble cutting the PVC pipe
The Saw Max has no trouble cutting PVC pipe.


I cut two pieces of metal: a 19mm (0.75 inches) tube with a 1mm (0.03 inches) wall and a solid 12.5mm (0.49 inches) rebar rod.

The Saw Max handled the metal well, although you must take care to not overload the motor.


The Dremel DSM20 Saw Max sells for just over $112 on Amazon.

If you use it as intended, it’ll give you hours of cutting pleasure. It’s worth every cent.

Replacement blades cost

Here’s what you’ll pay for Saw Max replacement blades:

  1. DSM500 – $6.97 (1 of).
  2. DSM510 – $9.97 (3 of).
  3. DSM520 – $4.20 (3 of).
  4. DSM540 – $23.38 (1 of).
  5. DSM600 – $10.49 (1 of).


This, from the Dremel SM20 Saw Max Amazon page…

Backed by a two-year warranty

That’s a decent warranty. To be expected from a company like Dremel.

Technical specs

Technical specs for the Dremel DSM20 Saw Max.
Weight1.7 kg (3,75 lbs)
Length390mm (15,35 inches)
Width100mm (3.93 inches)
Height270mm (10.63 inches)
Speed (no load)17,000 RPM
VoltageAvailable in 120 and 220 / 240.
Power710 watts
Power cord length2,450mm (96.46 inches / 8 ft). Might be slightly shorter in the USA.
Sound pressure96 dB
Sound power108 dB
Vibration3,3 m/s

Final thoughts

The Dremel DSM20 Saw Max is an excellent tool for cutting a variety of materials up to 20mm thickness. (Don’t cut metal of 20mm thick; use a heavy duty tool for that. The Saw Max handles metal rod of up to 8mm only.)

Here are six reasons why the Saw Max is fantastic…

It’s versatile. Cut wood, metal, plastic, brick and tile with the Saw Max. The only limit is the thickness of the material you’re cutting.

It’s quick. The Saw Max runs through material quickly. It makes other cutting tools look bad.

It’s easy to use. Add a blade, set your height and start cutting. It’s as simple as that.

It’s accurate. With an easy-to-follow line of sight and a thin kerf, the Saw Max gives you as accurate a cut as your hand and eye allow.

It’s smooth. Run a jigsaw through thin material once and you’ll not do it again. Because the Saw Max is a unidirectional tool, it doesn’t rip your job apart.

It’s clean. My baby angle grinder, when I use it with my right hand, rotates towards me. Have you any idea of the junk it dumps on you when you cut? The Saw Max cuts away from you, whether you use it with your right or left hand. Furthermore, the Dremel comes with a vacuum nozzle, which allows you to suck up shavings while you cut.

I love the Dremel Saw Max. It’s proving to be a must-have tool. I think you’ll like it too.

Gyokucho 372 Dotsuki Takebiki Saw

The Gyokucho dozuki saw is a fine example of common sense. While a western saw cuts on the push, a dozuki saw cuts on the pull.

A while back I had an interest in Japanese carpentry, and although I didn’t pursue it, I watched a load of related YouTube videos.

These videos highlighted two tools: the dozuki (or, dotsuki) saw and the kanna (Japanese plane).

The dozuki is a backsaw, but it’s different from a western backsaw (like a dovetail saw), in that it cuts on the pull, not the push.

My wife bought me a Gyokucho 372 dozuki saw for Christmas. (The 372 is best suited to delicate work.)

I never used it. It was too beautiful. I stuck it in a drawer and left it to gather dust.

But the other day I needed to cut balsa wood, so I took it out.

The Gyokucho dozuki saw is a phenomenal woodworking tool. Here’s why.

Easy to use

The dozuki cuts on the pull stroke, making it easier to use than a traditional western saw.

If you’ve never worked with a woodworking saw, but you’d like to, the dozuki is a great tool to start with.

If you’re a veteran woodworker, you’ll get the hang of the dozuki in no time.

Delicate work

The Gyokucho 372 dozuki is not a heavy duty saw. It’s made for delicate woodwork.

Use it for cutting small dovetails and tenons.

Even though it’s made for fine work, I used it on pine and PVC pipe. It outperformed a western backsaw by far in both those cases.

Thin cuts

Because the dozuki cuts on the pull stroke, the blade is thinner than those found on western saws.

A pull cut does not need as sturdy a blade as a push cut. If a western saw’s blade isn’t sturdy, it’ll bend and / or break.

Since the dozuki’s blade is thinner, it cuts a thinner slit (kerf).

This is handy for delicate work, which is what the dozuki excels at.

The dozuki saw (bottom) has a much thinner blade than a standard off-the-shelf western backsaw
The dozuki saw (bottom) has a much thinner blade than a standard off-the-shelf western backsaw.

Narrower cutting

Because the dozuki has small teeth with a small pitch, you can make narrower cuts.

There are enough teeth in contact with the work-piece for it to give a smooth cut.

Large teeth are best used on large cutting surfaces.

Replaceable blade

The dozuki saw’s blade is replaceable.

If your blade is done, remove the old one and slide in a new one.

In less than a minute your dozuki is ready for action. Easy.

How to use

I read somewhere that you’re supposed to hold a dozuki with both hands.

If that’s your thing, go for it.

I use one hand and start the cut with the dozuki at a 45 degree angle to the plane I’m cutting into, to ensure that the saw gets a good lead into the material.

Once the saw is in deep enough and I have a rhythm going, I flip the saw handle up and cut horizontal strokes.

Remember, don’t apply pressure on the push. The dozuki needs hardly any force, but if you do apply pressure, do so on the pull.

Tooth pitch

The Gyokucho 372 comes with a 19 TPI pitch.

I bought a standard, off-the-shelf MTS backsaw with a pitch of 11 TPI.

There’s a remarkable difference in cutting. The dotsuki cuts much smoother.

Benefits of a fine pitch

A saw with a fine pitch takes longer to cut through a work-piece, but offers the following benefits:

  1. It allows you to cut narrower material.
  2. It’s perfect for delicate cutting.
  3. It doesn’t rip apart soft wood.
The dozuki saw (top) has a much finer tooth pitch than the western backsaw
The dozuki saw (top) has a much finer tooth pitch than the western backsaw.

Cutting tests

To test the dozuki, I cut pine, balsa and PVC.


Balsa is so soft enough to cut with a plastic knife. Pine is more challenging.


I stacked and glued 10 mm thick balsa wood. The dimensions of this block is roughly 100 mm x 50 mm x 50 mm.

I cut half of each block with the standard backsaw I bought from a local shop, and the other half with the dozuki.

Two blocks of 100 mm x 50 mm x 50 mm balsa wood
Two blocks of 100 mm x 50 mm x 50 mm balsa wood.

The two balsa blocks gave me an opportunity to rip-cut and cross-cut.

(What will I do with these blocks? Probably shape some crankbait fishing lures.)

The dozuki gave a much smoother cut with the rip-cut than the standard backsaw.

The dozuki did a fantastic job with cross-cutting the balsa wood, whereas the standard backsaw had a tough time making it through.

In fact, I couldn’t keep the standard backsaw from going off course, while the dozuki stayed the course without much guidance.


I bought a length of 40 mm pine. The actual width and height are ~43.3 mm x ~42.4 mm.

A length of square 40 mm pine wood
A length of square 40 mm pine wood.

The dozuki worked FAR better than the standard backsaw on the pine.

In fact, I timed how long each tool took to cut through the pine.

It took me 150 seconds with the standard saw, while the dozuki only took 20 seconds. Vast difference.


PVC is outside the dozuki’s scope, but I wanted to see what these saws would do to plastic.

For this test I cut a 40 mm PVC tube with a wall thickness of 2 mm.

The dozuki flew through the PVC tube in five seconds, while the standard saw slogged through in 16 seconds.

Can you sharpen it?

You can attempt to sharpen the dozuki’s teeth, if you’re brave.

The model I bought has 174 minute teeth.

If you assign a sharpening and setting time of 30 seconds per tooth, that translates to 87 minutes of work.

That’s if you’re skilled at sharpening small saw teeth.

There’s one more thing. Gyokucho hardens their dotzuki’s teeth. You’ll have a tough time trying to sharpen them with standard files. You’ll need diamond coated files.

But these blades aren’t made to be sharpened. They’re made to be replaced.

How to remove the blade

Follow these steps to remove the blade:

  1. Loosen and remove the locking screw.
  2. Slide out the back and blade from the handle.
  3. Slide the blade from the back.

Where to buy new blades

You can buy new dozuki blades online from Hida Tool.

Old blades

Since Gyokucho hardens their blades, you can grind off the teeth of your old blades, cut them up and use them as scrapers.

Or use them as straight edges.


The Gyokucho 372 dotsuki saw sells for $40 on Amazon.


I couldn’t find ANY warranty info on the Gyokucho dozuki, or any of their other products, for that matter.

I emailed what looked like an official Gyokucho website. If they reply, I’ll update here.

Technical specs

Technical specs for the Gyokucho 372 dozuki saw. Metric & Imperial.
Weight213 g7.51 oz
Length598 mm23.54 inches
Width~21 mm~ 0.83 inches
Height (toe)68.3 mm2.68 inches
Height (heel)55.2 mm2.17 inches
Maximum cutting depth~43 mm1.69 inches
Cutting length225 mm8.85 inches
Blade thickness0.3 mm0.01 inches
Teeth typeRip cut
Number of teeth174
Handle materialCane-wrapped wood

Eastern VS western woodworking

Debates about eastern woodworking VS western woodworking abound.

Some eastern woodworking techniques make more sense than western woodworking techniques, while the reverse is also true.

In many ways eastern woodworking is far different from western woodworking.

For instance, many eastern woodworkers sit on the floor and clamp their work-piece with a foot. That’s a far cry from the lofty woodworking tables favoured in the west.

It seems eastern woodworkers prefer simple tools, while western woodworkers prefer intricate tools.

A marriage is inevitable. If you’re in the western world and start using some eastern woodworking tools, you’ll value them as part of your arsenal.

But in the end, it’s personal preference that dictates what you load your toolbox with.

Final thoughts

The Gyokucho 372 dotsuki is a lovely woodworking saw.

It’s easy to use. Because the dotsuki cuts on the pull stroke, it cuts easier than a western type saw.

It excels at delicate woodwork. The dotsuki’s blade is thinner than a western backsaw’s. Its teeth are minute, and the 372’s tooth pitch so fine that it’s perfect for making delicate woodworking cuts.

The blade is replaceable. The Gyokucho dotsuki’s blade is easy to remove. But don’t try to sharpen one. Gyokucho hardens their saw blades. Buy a replaceable blade and get back to cutting in less than a minute.

If you’re looking for a beautiful woodworking saw for fine work (such as cutting small dovetails and tenons), get the Gyokucho dotsuki.

Warthog V-Sharp Classic II

I bought the Warthog V-Sharp Classic II knife sharpener a while ago. Is it a good tool for sharpening knives? Read on to find out.

My wife and I were walking the mall, searching for a gift for a friend.

My friend’s a knife enthusiast, so we entered a hunting shop.

After finding nothing suitable, the shop owner pulled a dental torture device (that’s what it looked like) from a rack and placed it on a table before me.

The shop owner took a knife, flicked it open and pulled it through the tool.

My jaw dropped.

I had to have this contraption.

Never mind the buddy we’re supposed to be getting a gift for. He’d have to settle for a card.

I didn’t buy this majigger straight away. I feigned self-control for a few days, set a date and fetched it. It was a momentous occasion. Couldn’t wait to get home and sharpen anything and everything.

The Warthog Classic 2 is amazing for three reasons.

Easy to use

The Classic 2 is a plug-n-play type sharpener.

You remove it from the box and start sharpening your blades.

I don’t know why they included a usage DVD. It’s not necessary.

Saves time

A dull blade only irritates you if you know the worth of using a sharp one.

So go ahead and keep using a dull blade and hack away at whatever you’re cutting.

But once you taste the smooth, easy cutting of a sharpened edge, you won’t be happy using a dull edge.

And although various sharpening tools give you excellent sharpness, few give it to you with the ease and speed of the Classic 2.

Saves energy

We eat plenty of meat and vegetables.

Some foods are difficult to cut, even with a sharp blade. My wife often summons me to the kitchen to help her cut an unmanageable fruit or vegetable.

Throw in a blunt edge and you’re climbing a mountain with a rabid monkey on your back.

A sharp blade makes cutting tough fruits and veggies easier.


Some of the Warthog Classic 2’s parts are metal; some are plastic. All the parts will give you long life.

The sharpening hones will give you many sharpening sessions before they need replacing.


You don’t use lubricant for sharpening with the Classic 2.

The honing stones are diamond-coated. They’re made for dry sharpening your blades.

You’ll clean up a tad of dust, but there’s no grime.

No electricity

You can buy an electric knife sharpener, but you’ll need an electrical outlet to use it.

The Classic 2 is perfect for any sharpening situation, indoors or outdoors. You can sharpen anytime, anywhere.


The Classic 2 isn’t perfect (although it’s close). Here are my main issues with it.

It can’t reach the back

The Classic 2 can’t reach all the way into the corner of a knife’s ricasso. (The ricasso is a bit of unsharpened blade at the heel of the knife.)

The diamond hone rods are difficult to remove

Changing the sharpening angle requires the removal of the rods that hold the honing stones.

It’s a difficult task. You get used to it, but it takes a fair amount of finger pressure to unclip.

The knife guide is plastic

The guide against which you slide the knife down when sharpening, is made of plastic.

I have no problem with this, but some people might hate it.

Smooth (double bevel) blades only

The Classic 2 can’t sharpen serrated blades.

It also can’t sharpen a single bevel knife, since it uses a hone on either side of the knife to guide the knife while sharpening.

But it does a fantastic job of sharpening smooth blades. That’s enough reason for me to love it.


You can buy the Classic 2 online for ~$75. That excludes shipping.

Compare this to knife sharpening services in the USA. You’ll pay from $1.75 to $3 per inch. Add shipping—$5 per order—and your bill for sending in knives soon surpasses a Warthog’s price.

Let’s do some calculations.

I sharpened 12 blades with a combined length of 1,673mm (65.86 inches).

The 12 knives I sharpened with the Warthog V-Sharp Classic 2
The 12 knives I sharpened with the Warthog V-Sharp Classic 2.

Let’s cut the outsourced sharpening price to $1.50 per inch AND exclude shipping costs.

65.86 inches x $1.50 per inch = $98.79.

It would cost you $98.79 to have your knives sharpened by someone else. Remember, that doesn’t include shipping.

That’s for every time you want your blades sharpened.

The Classic 2 lets you do the job at 23 percent cheaper. And you pay for it once and use it over and over and over.

You save plenty of money.

Besides, what if you want to try a different angle on one of your knives? The Classic 2 allows you to experiment. If you don’t like the new angle you’ve given your knife, sharpen it to another angle.


The Classic 2 comes with a guarantee. Here it is, verbatim:


Warthog Blade Sharpeners warrants that our Sharpeners and Diamond stones will be free from defect and that only the best Quality material is used to manufacture this product. The Guarantee is granted safely to the Buyer. Warthog Blade sharpeners will replace any defective products free of charge. Buyer must return the defective product to Warthog Blade Sharpeners for inspection. Warthog Blade Sharpeners have no obligation under this Guarantee if the product is mistreated or modified, or if the product has not been used according to its instructions.

Consequential Damages: In the event the manufacturer shall not be held liable for any special indirect incidental or consequential losses or damages allegedly attributed to this product.

Warthog Blade Sharpeners International
PO Box 3190, George Industria, 6536
Tel: 044 874 1411 / 1442 Fax: 086 529 1309

Warthog diamond stone

Warthog Blade Sharpeners manufactures high quality diamond stones that are free of defects. Diamond stones will retain their cutting ability for years of use. Diamond stones are manufactured for hand sharpening and not for motor-driven application. Initially your diamond stone will seem especially aggressive. It will smooth over time. When sharpening you need not to exert pressure – let the diamonds do the work. To test diamond stone use it on glass (ashtray or bottle, if it scratches the glass the diamonds are still in tact.) Diamond stones can be used to dry or use water for lubricant. Do not use oil on diamond stones. When sharpening it fast, use water or water with a little bit of dishwashing soap to keep the stone cool and prevent it from clogging. When cleaning is needed use soap water and a scrub brush, do not use petroleum-based cleaners.

Click here to download a PDF version.

In the box

The Warthog V-Sharp Classic II box contains the following items:

  • Warthog V-Sharp Classic II.
    • Black, but also available in blue, red, silver and white.
    • Two hone rods with diamond hones included and mounted, ready for use.
  • Usage instruction DVD.
  • Usage instruction pamphlets.
  • Warranty pamphlet.
  • Brochure for other Warthog sharpening products.

How to use

It’s easy to use the Classic 2. Follow along, but…

Before you start

Before using the Warthog V-Sharp Classic 2, know the following:

  • Don’t use oil for sharpening with the Classic 2.
    • Use water when using diamond hones.
  • Wear gloves to keep from getting cut.
  • Press your knife’s cheek against the blade guide when you pull it through the Classic 2.
    • Not too hard. The guide is made from plastic and can bend.
  • Don’t apply pressure to the spring-loaded rods when you sharpen.
    • Let the diamond hones do their work.

Follow these steps

How to sharpen a dull blade with the Warthog Classic 2:

  1. Remove the Warthog V-Sharp Classic II from its box.
  2. Keep the Warthog steady by holding it by the thumb grip.
  3. Run your knife through the Warthog with your other hand, using an up and down, back and forth sawing motion.
    • Keep the blade’s cheek against the blade guide.
    • Do this 30 to 40 times.

That’s three steps.

No assembly or tightening required. No lubricant required.

How to touch up a blade with the Warthog Classic 2:

  1. Run your blade through the Warthog in a downward motion, out of the sharpener.
    • Do this ten to 15 times.

Once you’ve sharpened a blade, you only need to touch it up now and then.

Check the 12 second video for a demo.

Steeling your blade

You can steel your sharpened blade with the Classic 2. Follow these steps:

  1. Unclip the honing stone rods.
  2. Flip them over and clip them back in, steel rods on the outside, but at an increased angle.
    • If you sharpened your knife at 20 degrees, increase the angle to 25 degrees. If you sharpened at 25 degrees, increase the angle to 30 degrees.
  3. Pull your blade through, ten to 15 times.

This 24 second video shows you how to set up your Classic 2 for steeling a blade.

Sharpening thick blades

To sharpen a thick blade, you need to adjust the blade guide.

Follow these steps to adjust the blade guide:

  1. Loosen the blade guide locking screw.
  2. Tilt the blade guide as far back as possible.
  3. Tighten the blade guide locking screw.

Now you’re able to sharpen thick blades, even an axe head.

This seven second video shows you how to set up your Classic 2 for sharpening thick blades.

The honing rods are marked at the top and the bottom. You won't get confused when you change the sharpening angle or replace the hones
The honing rods are marked at the top and the bottom. You won’t get confused when you change the sharpening angle or replace the hones.

Sharpening angles

The Classic 2 gives you three sharpening angles:

  • 20 degrees
    • Recommended for boning, carving and paring.
    • Slicing edge for meats, veggies and soft materials.
  • 25 degrees
    • Hunting knives, pocket knives, chef’s chopping knives.
    • For cutting on hard surfaces.
  • 30 degrees
    • Steeling and rough cutting work.
    • Durable bevel, great for chopping.


Because the Classic 2 uses the blade’s edge as reference, you get an accurate angle that remains the same, session after session.

This is not the case with sharpeners like the Lansky Deluxe, which uses the blade’s spine as reference.

When you use a Lansky Deluxe, chances are you change the sharpening angle every time you re-sharpen a knife. Unless you marked your Lansky’s position on your knives. That’s a schlep.

Sharpening grit

The Warthog V-Sharp Classic II comes with two 325 grit diamond stones.

You can buy the following diamond stones for it:

  • 270 grit.
  • 325 grit.
  • 600 grit.
  • 1000 grit.

Use the coarsest stone (270 grit) for rough edges. Use the finest stone (1000 grit) for finishing an edge.

How to exchange diamond hones

The Warthog box claims that it’s easy to remove the diamond hone from the rod.

I needed the help of my trusty stubby screwdriver.

This 16 second video shows how I remove it and slide it back.

How long does a blade stay sharp?

There’s no clear answer to this…

A blade’s toughness depends on the type of material it’s made of, as well as the heat treatment it’s received.

Your blade won’t stay sharp if it’s made from an inferior material, or if they messed up the heat treatment process.

How long it takes to sharpen a new blade

This depends on the condition of the blade.

Let’s do some calculations, based on Warthog’s instructions for using the Classic 2.

Warthog says you must sharpen a dull blade by pulling it through the Classic 2, 30 to 40 times, using a sawing action.

This is a quick action, so we’ll assign a second to each pull.

We’ll also double the number of times you pull it through, because we can.

Warthog says it takes ten to 15 slow pulls through the Classic 2, to finish the sharpening process.

We’ll do it thirty times, and count two seconds for each pull.

So we have 80 saw-like pulls, at one second per pull, and 30 slow pulls, at two seconds per pull.

That gives us a total of 140 seconds.

Let’s add steeling to the process.

Steeling requires you to unclip the honing stone rods, flip them over and reattach. We’ll assign 30 seconds to this action.

Then you need to run the knife through the Warthog another 15 times. We’ll double it, and assign one second to each pull.

140 seconds + 60 seconds = 200 seconds.

The fast, saw-like action required for dull blades takes practice to perfect. So you’ll start off slow.

At a slow pace, you can sharpen a blade in less than ten minutes.

Once you get the hang of the Classic 2, you’ll sharpen a blade in less than four minutes.

Technical specs

Technical specs for the Warthog V-Sharp Classic II. Metric and Imperial.
Weight541 grams1.19 lbs
Height210mm8.27 inches
Width220mm8.66 inches
Breadth57mm2.24 inches

Final thoughts

I love the Warthog V-Sharp Classic II.

It’s easy to use. Remove it from the box, set your desired blade angle and pull your knife through. Knife sharpening can’t be easier.

It’s clean. It uses diamond coated hones for sharpening. You don’t use oil for sharpening with these hones.

It’s consistent. Because the tool uses the blade edge as a reference point, as opposed to a clamping position on the knife’s spine, you never have to refresh your sharpening angle. The difference in angle, from one sharpening session to the next, is minimal, if any at all.

No electricity needed. Take the Classic 2 outdoors. It’s small enough to form part of your camping kit. And it’s manual. No need to plug it in.

The Warthog Classic 2 is hard to beat. It’s a premium knife sharpening tool. I recommend you get one.