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" But I’m 100% convinced any thickness could be used"

I know 6 inch will work - You just rip it to 3" and it works every time.

So, clay, what ur saying is only one thickness can ever possibly wrap a particular drum?

Mike, in the ultimate showing of Brad has too much free time...

Here are a couple videos where I do the patented roll paper test with both 2 1/2" and 2 3/4" paper. Hopefully this shows what I mean and if you can come up with some way to not have to cut the paper that is great. Or better yet, if you come up with a way where it will work for all drum widths, even better!

Plus it was fun to learn how to use my son's GoPro.

http://www.youtube.com/watch?v=_DPCIHDj ... e=youtu.be

http://www.youtube.com/watch?v=Sx9gO8sT ... e=youtu.be

Sorry about the dust collection hose getting in the way. Also, I could have done better with angling the camera. Maybe next time!

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I'd like to hear more about this idea. You just tape the final edge of the roll to the drum, instead of fighting to insert it into the clip? Brilliant! Fiddling with those stupid clips has taken the fun out of my workshop time on more than one occasion.

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George :-)

"I'd like to hear more about this idea. You just tape the final edge of the roll to the drum, instead of fighting to insert it into the clip"

It does work, but you lose an inch or two of sanding width. I use strapping tape or cellophane tape and wrap it completely around the drum and edge of the sandpaper (sometimes more than once). You have to stick the ends down good so it doesn't peel off when the drum is spinning. It is a little easier on the fingers, and when the end that goes into the clip tears off and leaves the strip an inch too short it allows you to continue using it.


"So, clay, what ur saying is only one thickness can ever possibly wrap a particular drum?"

No, actually if you don't mind a small portion of the end of the drum not being covered by sandpaper, you can cut an angle on the opposite (inner) side of the strip so it can slip into the clip.

Very interesting. Nothing like a video example to illustrate the problem. I looked at the manuals for the 16 and 22 inch drums. They provide the same info. The paper diagram shows a 15 3/4" taper, and is based on a 3" width of paper. Let me get my pencil and calculator out. Thanks Brad. Excellent work.

I have a formula to test. Maybe, Brad, you can try? It defines the straight length along the edge to determine the taper. Use it to mark the paper, draw a straight line across the paper, and then use a straight edge to mark the taper from there to the corner. The rest is as you did it before. If it works, I will explain more:

This assumes a drum sander with a 5" diameter. The Jet 16" is 5". L is straight edge length of taper (not the angled length)

L = sqrt(w^3/(DL/nwraps - w))

w is paper width, nwraps is what you see on drum with 3" paper, counted from taper cut point to taper cut point. I see 7 on my 22" drum. DL is drum length. Everything is in inches. For my sander, I get around 15.5" for 3" and 7.5" for 2.75". 5" for 2.5". You will need to do your own calculations for 16" drum. The square root and possibility of a negative number limits things. This means for wider paper, number of wraps is reduced. Kind of makes sense.

My length of 15.5 is precisely correct based on manual. sqrt(3^2 + 15.5^2)=15.78 (close enough to 15.75)

I just noticed something in the equation. Drum diameter not there. So it will work for any diameter as long as you know the number of wraps for the paper it was designed for. (3")

I will give it a try later tonight. I’ve got half a dozen things going on in the shop today.


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Me too. You got me stuck on this. Dang it. U might ask why 15 3/4 works for 10-20, 16-32, 22-44. Good question. I think 3" paper width drove design lengths. There appear to be other tapers that work. Also turns out that the numbers I calculated above for 2.75" (7.5) will work on your drum. For 2.5", same thing.

Maybe. There will probably be a downside to this in that some of the end of the drum will be unusable.

What I noticed was that the number of wraps with 3” paper was always drum length - 1 / 3. So for my 16” it was 15 / 3 so 5 wraps.

Same for 22” drum - 21 / 3 = 7 wraps.

Any idea where that 1” consistently gets lost? The paper goes edge to edge so why is it consistently drum width - 1?


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I don't know. What I do know is this is based on "wrapping efficiency". The ratio of the drum area to the paper area. For the 2.75 and 3 paper, there is only 5 and 7 wraps possible (on 16 and 22)

For the 2.5" paper, on your drum. there is 5 and 6 wraps possible. 5" edge, 11" edge.

I take it all back. This problem does not appear to have a (good) solution. Other than Abranet making proper widths. There appears to be one where you make a longer (MUCH longer) taper, but who wants to do that?

How many luthiers does it take to wrap a sanding drum.......

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It is a surprisingly difficult problem. One that does not appear to have a simple solution without leaving gaps. What makes it really hard is ending up at the right location where the clips are. Jet sanders are ubiquitous. Why would Mirka make a width jet sanders cannot use?

I think I’ve figured it out. 2 3/4”. What u think?

Looks good. What’s the formula?


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No formula Brad. 15 3/4” taper as per manual. But, ignore the 3” clip off end. Use only half or so of the clip width. Apparently that’s the key. Have no idea if this would work for 2.5”. Maybe you could verify?

Wow, that is really surprising! I will give it a try.


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The clip channel is 1.25” wide. I noticed on all my current rolls I was only using 0.8”. Got me thinking. Maybe the idea of that width is for some flexibility on width.

The Abranet is not marketed for drum sanders. It’s for Mirka’s palm vac sander.


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Please do Brad. I feel awful for spending my whole day on this. Lol!!

Not true. That was the whole point of this thread. Abranet makes drum rolls. Or at least, it was one of the points.

Brad, how did u figure out 2 1/2 would work?

Because I was focused on the number of wraps. At 2 1/2” each wrap was 1/2” short of where 3” paper landed. Since the 16” drum took 5 wraps and each wrap was 1/2” short it left me with 2 1/2” or one more full wrap.

I know what you mean about Mirka selling Abranet on a roll, but I don’t think they are targeting that for drum sanders. Their palm vac is 2 3/4” wide and it’s pictured on the wrapping for the roll.


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