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I saw that there was considerable interest in this topic on another thread. I built this sander 25 years ago and have used it in building over 150 guitars. In addition to thicknessing tops, sides and backs, I use it to straighten neck, blanks, fret board blanks, bridge blanks, bracing etc. Flatten one side on a jointer, then straighten and dimension the other on the sander. I even use it on bone nuts and saddles. One turn of the adjusting rods reduces thickness by .1 mm and, of course you can use quarter turns or half turns for very fine adjustments. The dust collector works extremely well with a shop vac. The drum is 20 inches wide and 4 inches in diameter. I had it made from steel (oil well drill pipe) at a machine shop. The whole thing cost me less than $300. I've tried lots of commercial sanders and wouldn't trade this one for any of them.

Nice, wondering how the abrasive's held on the roller

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Please be careful! Google De-Gloving injury if you don't know what can happen if you're not.

Mark

You had to go and make me curious

Ed

I'm curious. Why would u mention degloving in conjunction with this post? Just how is this device different/more dangerous than any other drum sander? (unless ur referring to the drive belt). Not only that, but the builder appears to have extensive years of building.

This one is especially nice and looks as safe as any retail version! I posted as a general warning for DIY tools and because I saw an unguarded drum on the previous drum sander. I'm a worry wart and have seen some nasty stuff as an Army medic and later as a Respiratory Therapist working in the Burn Unit where degloving injurys are treated.

"Just how is this device different/more dangerous than any other drum sander?"

The reason this sander is more dangerous is that the wood must be manually fed through the machine, which can create a situation where fingers and hands could be pulled into the drum if care is not used to avoid this. With care I'm sure it could be used safely, and even the commercial units that feed the wood through the machines can be dangerous if operated negligently.
Having had the end of a finger ground down to the bone (and some of the bone ground off) by a belt sander. I have a good understanding of how difficult it is to extract a body part from a sander that is trying to pull it further in (I couldn't do it but thankfully there was someone close by who quickly pulled the plug). Some tools leave pieces that can be sewn back together. Sanders, jointers, and planers only leave hamburger.

While no safety warning should ever go unheeded, the drums on a thickness sander turn in such a way that actually pushes the wood away while being fed otherwise they would suck the wood in and jamb instantly, or shoot it out without getting much sanding done. Always be careful but having a hand pulled in to a drum sander would be very difficult.

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Thank You and Best To All

Typically we are grabbing the wood as it comes out the back side, and although the wood is pushing out it's still good to remember that that's a dangerous side of the machine.

New username, same Pat Mac

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Pat

All of the above, plus the exposed drive belt on this particular DIY sander gives me the willies. So, I don’t think I can agree that this sander is as safe as a commercially available drum sander. Having said that, homemade machines can be tweaked to add enough safety features so that their utility, AND safety, exceed what is commercially available. This machine looks like one that would earn that praise, if it had some safety features added on.

It is true that we are pushing stock in against the rotation of the drum on these shop made sanders but it is good to remember to be careful when pulling small parts out the back. I will occasionally run a short piece through mine and there is a temptation to reach around and grab the other end to pull it out. . .

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

"I will occasionally run a short piece through mine and there is a temptation to reach around and grab the other end to pull it out. . ."

Don't do it Bryan. Resist that temptation. Use a push stick that is a little thinner than the work piece that can push it through from the in feed side.


Hi Larry,
I know that the rotation of the drum would tend to push your hand away when it's on the infeed side, but with manually fed machines at some point you need to finish pulling the piece through from the out feed side. I see that as the biggest advantage of the self feeding machines.

Yes, this is exactly why I posted that. Even though I know better, the temptation exists. I wanted to spell it out for anyone who hadn't thought of how badly it can turn out.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

For a drum sander that does not have a feed system (or I guess we can say that the feed system is manual), I think the safe thing to do is to always have the workpiece ride through the sander on a sled, and have the tail of the sled be long enough that you can push the workpiece completely through to the other side of the drum while your hands (which are pushing the back of the sled) and still a safe distance from the drum. By that point, nothing is being sanded, the sled won't be launched backward because nothing attached to it is touching the drum, and you can safely pull the sled the rest of the way through.

It's a hassle, but that's the price to be paid for not building/buying a feed system.

99% of the time, the stock to be sanded will be past the back edge of the table before it makes it completely past the drum. You can safely grab the overhanging stock and pull it out at the same rate as you were pushing it in. That far away from the drum, if the stock gets caught on the drum and pushed back through the sander it is just pulling it out of your hand. The danger is when you are reaching in close to the drum (on the back side) where you or your shirt could get suddenly pulled in.

I try to always be standing on the side of my sander pushing stock in with my left hand and pulling it out with my right (from a safe distance). This keeps me on the opposite side of the machine from the belt and out of the way of anything that might come shooting out of the front. You can't always stand on the side but I do whenever I can.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Hi Don,
I was also thinking about the sled idea. If the "stop" the work rested against was far enough up and low enough it could also pass under the drum, and after the work pieces were removed the sled could be pulled back into position safely. For long pieces it might not be necessary, as Bryan says, but for short stuff it might add a margin of safety.

OK, I see the point about the hand forced feed. I would not want to deal with that. Those "degloving" pictures grossed me out.

Yep, that works, too. I see Bryan's point about longer work, but really, we are planning for when things go wrong, not when they go right. If the operator is being completely attentive, the odds are always better for the operator. If I was pulling a side (for instance) through a drum sander, and the drum grabbed the side and decided to sling it backward, I would like to think that I would have the good sense to let go. But what if this all happens so fast that I can't react fast enough, and what if I had momentarily allowed my hand to get within a half foot of the drum while I was pulling the side through? Stuff goes wrong. We should plan for it to go wrong, and ensure that such mistakes only result in ruined work, not ruined bodies.

I grew with you Don, 100%. I am certainly not advocating being lazy about safety. With my sander, the outfeed table is long enough that a back or top is off the table just before it is through. My hand is at least a foot away from the dust cover when I grab the back part to pull. I do think think I could hold the plate tight enough to pull my hand/arm that far. I’m pinching a thin board between my finger and thumb tips it would get pulled out of my fingers rather than bringing me in. Keep in mind, my hand is now beyond the table. Now if my hand were in a position to get caught between the work and table or dust cover, that would create a situation where my hand could be trapped and pulled.

Again, i’m nod advocating complacency! I just don’t want someone to misunderstand my other posts and get in trouble.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Hey, any tool is dangerous. I love my Performax 22/44, but I finally gave up wearing a tie when using it.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I found these posts interesting in that they nearly all focus on safety issues rather than the efficacy of the design. Most of the posts expressing concern are entirely valid of course as are the posts outlining techniques that address many of the issues. My glaring omission is my ongoing failure to fashion and attach a belt guard that I've been telling myself to do for 25+ years.

But, for anyone who needs a thickness sander but can't afford a good commercial unit, this design works incredibly well in terms of accuracy, dust collection, flexibility and longevity of the abrasive. Controls at both ends of the drum even allow for shaping plates thinner at the edges than the centers.

Needless to say any tool, power or hand is capable of inflicting serious injury as a result of improper or careless use. Some more serious than others. My table saw probably scares me more than any other tool and I do my best to take no chances with it. In 39 years of guitar making (along with some furniture and toys) I've suffered one power tool injury, that being from running a piece of wood through a jointer. A small cut on the pad of my left index finger that required two stiches. But as careful and informed as I try to be I believe I may benefit more from good luck than brains

I practiced Orthopedics for almost 30 years and we saw every conceivable kind of power tool and industrial injury. The vast majority were table saws, miter or hand held saws. Those frequently resulted in digit loss of varying degrees. Occasional jointer injury which were usually on the top of the hand, knuckle area and usually fixable without digit loss.

I don't remember ever seeing a bad router, thickness sander, or band saw injury but did see some V belt cases, those were bad. Almost all of the finger degloving cases seemed to involve catching a ring on something. I quit wearing rings after the first one I saw.

Nail gun cases could be interesting. A GP in another town sent me a guy with a "locked knee". Turned out he had nailed his knee together with a framing nail.

The table saw is the bad boy in my experience and unprotected V belts really scare me.

Your sander is really cool, great design but make that belt guard today

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Michael,

Sometimes threads take their own direction. Lost in the shuffle was discussion of your design. I really like the way your bearing block screw adjustment works and may steal the principle someday. Do you find it is difficult to keep the table parallel to the drum with height adjustments on both sides. I like the option of taking more off one side or the other, but I don't think I would like having to adjust both sides every time I raise the table for the next pass. maybe it is not as big of a deal as I think. When I made mine, I used a vertical threaded rod to raise the front of the table from a single point. The problem with that is the rod is fairly long to allow for lots of thicknesses and it gets in the way sometimes.

I made my drum from MDF and trued it to the table with sandpaper. At the time, I thought getting the drum and table in the same plane would be problematic otherwise. I see lots of people have been successful otherwise so again, I may have been worried about nothing. . .

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

That is why I asked my initial question. I don't think the safety poster meant ill, some folks are compelled by their day job to notice these things. I've had a hammer go nuts on me befiore (hit my finger). Still use them though. and I agree, table saws creep me out.