# Hook and Loop Drum Sander Question



## shipwright (Sep 27, 2010)

I have a 25" dual drum sander by Canwood, a house name carried by House of Tools. If I had a can of green paint and the logo casting it could be a General International.

All that aside, my question is in regards to the hook and loop conversion that several LJs have done. I like the machine the way it is except for the issue of keeping the paper tight. The "spring loaded" clamps really don't work all that well and if the paper loosens, even just a bit, all kinds of burning and cursing ensues.

My question is about the "give" in hook and loop. There must be some loss in the absolute flatness that you get from the paper being backed directly by a metal roller. Am I wrong?

I use the sander to level the unevenness of veneer pieces in larger marquetry pieces and absolute flatness is really critical. Any high / low discrepancy could spell disaster.

Thanks in advance for your experience and help on this one.


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## SPalm (Oct 9, 2007)

Hey Paul,
My Jet drum sander has a metal drum, and the springs seem to hold paper pretty tight, so I have not considered converting it.

But I also have a V-Drum sander that counts on the hook and loop cushion. As the centrifugal forces push the paper out from the drum, only then does it contact the work piece. As long as the paper is wrapped in a semi consistent fashion, it sands flat and smooth. I would think the same principal would work here. Just take a light cut for the last one, and it should all work out in the wash. You also end up with a much cooler cut as the paper is just floating in air. It will be interesting to see what others say.

Steve


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## rance (Sep 30, 2009)

I find that really odd Steve. "Floating in air", interesting.  I'll have to think about that one.

Paul, I just installed H&L on a cylinder I turned on the lathe, about 2" in diameter. It is much different than your Drum sander in that it is out in the open air when used(on the lathe). However, with a little bit of attention, you can get the paper REALLY tight when wrapping it. The Hooks were wrapped in one direction and the sandpaper was wrapped in the opposite direction. This in itself tends to even out any bumps you might come up with.

Actually, bumps are rarely found since the paper is not 'required' to butt up the the previous wrap. Granted, you don't want to get too sloppy, but it doesn't have to be absolutely tightly butted up against the the previous wrap. This is working very well for freehand work it was intended for. I was actually wanting some of the spongyness, but it ended up being pretty stiff.

Technique can also play a part in getting your work very very flat. If you have the room, feeding the piece in at slightly different angles can help promote an even flatter surface. 5-8 degrees is enough. Imagine you had a board with a hard knot. By feeding it in at exactly the same angle, you could start forming a ridge the whole width of the board where the knot is. But by slightly skewing the board, any ridge that started forming at the knot would be removed by subsequent passes.

In the end, I believe you would be very happy with the results by moving to H&L.


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## SPalm (Oct 9, 2007)

Here is what Stockroom Supply (the V-Drum guys) says about converting a normal Drum to Hook and Loop:

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*Can I convert my existing Drum Sander to hook and loop?*

Yes, you can, but be prepared that converting your Drum Sander over to the hook and loop fastening system is going to change everything you have been taught about how to sand with your drum sander. All drum sanders are designed to pinch the sandpaper between the drum and the wood in order to cut. This is what creates heat. Heat then breaks down the resins in the wood, allowing the sandpaper to load up and burn the finish. Also, hook and loop conversion CANNOT withstand heat. It is made from plastic and if it heats up, it will melt. When you have the hook and loop system on your drum, you need to change the way you have your drum set up in order to prevent heat from building up. With the hook and loop system, when the drum is turned on, the paper actually lifts off the drum. This is called centrifugal force and it is the basis behind making the hook and loop system work for you. You will want to set your drum up so that the drum is not touching the wood, but when you turn your drum on, centrifugal force will lift the paper off the drum to allow it to sand. You may have to change this adjustment depending on which grit you have on your sander. This will leave an air gap beween the drum and paper preventing heat build up. This is a completely different concept than most people are accustomed to, but is the only way to make the hook and loop system work. People either love this system or hate it. The ones who hate it are the ones who cannot understand this new concept. The ones who love it will never go back. Also, when switching to this system, we recommend using 80 grit sandpaper and finer. Any coarser and the sandpaper causes too much drag and the sandpaper sometimes comes unhooked.

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I copied the above from this page.
http://www.stockroomsupply.ca/shop/faqs/

But again, I have not tried it on a normal drum sander. Sounds like it works for Rance. It seems like others have too. Maybe this is all hooey.
Steve


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## cathyb (Jul 8, 2009)

Hi Paul,
I actually have the General 25" double drum sander. Although I sometimes have issues with tension, it doesn't happen that often. After the purchase, the first adjustment I made was to buy the 2" wide rolls that are used for the Jet sanders. It's easier to get that paper tight. If I buy the large rolls in the box (the ones you have to cut for the final length), I sometimes use scissors to trim the end of the paper to get that perfect tail. Honestly, I much prefer the individual rolls since they rarely give me any trouble. I buy my paper from either Woodworker's Supply or Klingspor. My sander has been running almost flawlessly for five years and thousands of hours of use. I hope that bit of info helps…..... Good luck.


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## shipwright (Sep 27, 2010)

Thanks Steve and Rance. I still haven't heard from anyone who uses it in a closed context. ie: drum / paper / platen (belt). but I will have a look and maybe contact the stockroom supply link and see if they have my answers.
Thanks for your input.


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## shipwright (Sep 27, 2010)

Thanks Cathy. You and I were typing at the same time I guess. The paper I'm using is the cut to length roll (Klingspor) at about 3". I have 80 and 100. I'll look into the 2" rolls. 
If your's is General International, then I'm pretty sure mine came off the same assembly line right up to the paint department. I've examined them at a local store and they are identical to the smallest detail except that the general sits in a slightly wider support base.


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## rance (Sep 30, 2009)

Steve, I wasn't officially disagreeing with you.  However, after having thought about it a bit, I do disagree with that article. Keep in mind that I'm an armature, and they are professionals. At least they play as one on the internet. I've only done one, and they've done thousands, but I STILL disagree. What can I say, I'm an obnoxious rebel.

From what I saw when I wrapped the paper around the hooks, there's no way it is gonna rise up with a little bit of CF. In addition to the hooks tightly holding it in place, it has the added resistance from being stretched away from the hooks. Yes, I believe that paragraph IS a bunch of hooey. 

I'd be interested in anyone touching their drum after a long sanding session to see how hot it gets. Either kind.

PS: Misspelling above intended to drive home the point.


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## SPalm (Oct 9, 2007)

Re Rance:

This is how to set up a V-Drum sander, or abrasive jointer as I think of it. The paper really does lift off the drum. And this is how I set mine up. Then I don't move the drum height, but change grits to take more or less off. The V-Drum itself is a hard plastic type stuff.

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*How do I set up my V-Drum?*

Centrifugal force is the key element allowing the "V"-Drum Sander to work proberly. With your FINEST grit of sandpaper on the drum and your drum turned OFF, take a flat edged board and slide it over the drum. The drum should be below the table. This means that when you slide your board over, the paper will be touching ever so slightly but not enough to sand the wood or turn the drum. When you turn your drum sander ON, the paper will lift off due to centrifugal force and cause the drum to sand. Once you have this set up, you DO NOT need to change the height adjustment again.

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Here is the chart of particle size vs grit. If you put on 120 grit, it will remove about 4 thou of wood. It works, I have used a caliper to check the results. Weird.

320 = 0.00140
280 = 0.00172
240 = 0.00209
220 = 0.00257
180 = 0.00304
150 = 0.00363
120 = 0.00452
100 = 0.0055
80 = 0.00749
60 = 0.01045

And Paul, thanks for letting us use your posting. Rance and I go way back.
Steve


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## rance (Sep 30, 2009)

I just went to Stockroom's page referenced above. IMO, I am now even more leary of their advice. Aside from the lack of attention to spelling and such, they don't really qualify their advice in at least two areas.

1) "The paper keeps flying off the drum…" - They admit to their own advice not really solving the prolem and laugh it off with a lame joke. Then they say "Another reason *the paper SHOULD be coming off* is simply because it is worn out". So they designed a mechanism to automatically EJECT the paper when it needs to be replaced? I sure hope my face is not near it when it happens. Sounds to me that the transition from the clip to the surface of the roll has a tight bend in it. This should be ramped.

2) What motor size do I need and what speed should I be running the drum at? - They mention "As far as speed is concerned, this is going to depend on what kind of drive system you have.". Not really(IMO). I believe you should begin where the sandpaper meets the board. Start with the SFPM that the paper should be running at. Then work back towards the motor. Calculate by using the drum diameter, through the appropriate reduction ratio to get the motor RPM you are aiming for and the HP needed there. By calculating from the motor to the drum, they are essentially saying you can use any ole motor, but the drum speed may be as slow as mollasses. They never once even mention SFPM.

Sorry for the rant Steve. It is not directed at you, but at Stockroom. Again, I could be way off base here, I don't play for the Rangers. Please point out what I'm not getting.

Edit: We were both typing at the same time. Yes, Paul, I apologize for monopolizing. I should kindly butt out.  Oh, and Steve, my favorite phrase "Don't confuse me with the facts, I've got my mind made up.". All in good jest.


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## cathyb (Jul 8, 2009)

Hi Paul,
Yes, my sander is a General International and I initially used the 3" rolls, but found them hard to wrap well. Try the 2" rolls, they work much better…....


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## shipwright (Sep 27, 2010)

Thank You Cathy.

If it works for this:










I guess it works for this:










Is it a standard Jet part, no cutting required?
Is it a lighter weight paper or is it just the smaller width that makes it work better?

Thanks again


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## SASmith (Mar 22, 2010)

I converted a laguna 16-32 to hook and loop. My shop built v drum also uses it. Last week I put it on my grizzly 24" dual drum sander. I used 2" adhesive back hook from http://www.buyhookandloop.com/All.asp for all three. 
For less than $30 you can get enough to do three 25" long 6" diameter drums. I also wanted to use 2" wide adhesive hook for ease of installation. I think the conversion kits come with 4" or 6" which I think would be harder to install. I am currently running 4" loop back and sandpaper on all of them but next time I will be buying 6" paper. As to the question of flatness, I have seen no difference between the solid drum and the "cushioned" drum (with velcro). I have heard but never experienced rounding over of the corners of the edges from velcro drums.
I would not be without my velcro paper.
I stays cool and lasts longer/doesn't load or burn.
You also have more play when it comes to height adjustments.
You can run finer grit paper too.


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## cathyb (Jul 8, 2009)

Hi Paul,
At the moment I have the 3" wide paper from Woodworker's Supply part 118292 (100 grit). I thought those rolls were 2"wide, sorry I misspoke. My apologies…..This I know for sure, when I first bought my sander and used the General abrasive rolls, I thought I had made a huge mistake. At Woodcraft they said, "Switch to the abrasives used for the Jet or Performax and it will work better." I've never used the General abrasive rolls again. Scratch the 2" info, everything else is spot on. Yes, that beautiful green machine looks like mine, minus a few scratches and sawdust.


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## fge (Sep 8, 2008)

Not that i am adding anythinng new, but we added hook and.loop to our 26" steel city drum sander about 2 or 3 years ago and just love it. Never reallly even need to use the trailing clip.when using the hook and loop. I think it has been close to 3 years now since adding the hook and we are now faced with needing to replace it as it has become worn well.

Changing out the hook will be easy though.

I would never go without the hook and loop on my drum sander.


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## shipwright (Sep 27, 2010)

Steve and Rance, No problem.

These topics are here for all of us to learn and exchange ideas.

Thanks to everyone for the comments. In all fairness I likely won't be changing over (to anything) for some time because as long as I take care and get the paper tight and tape it there, the sander works flawlessly and I have confidence in sanding marquetry laden veneer surfaces with it, plus I have two half rolls (80 and 100) still in stock.

My question was more to see if anyone had any hard evidence that the H & L system could be trusted with this kind of precision because my gut tells me that it must have a higher likelihood of creating an uneven surface than a machined metal surface.

Thanks again


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