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Yikes. That's exactly what I was afraid of. Thanks for making it so vivid. Now I'll never do that.

bionta wrote:
"I've been too apprehensive to attempt planing very thin wood in my planer. Maybe I'd be more confident with a more modern machine (helical head?) but in the machine I have, I haven't tried anything below 3/16". I've been hoping to go the last step with the drum sander. Sounds like I have a learning curve to climb."

klooker wrote:
" I've had good luck using double stick tape & a carrier board,"

When wood gets too thin the planer wants to suck it up into the blades and turn it into wood chips. Sticking it securely to a flat carrier board allows you to take it down past that point. (but if it comes loose - wood chips!)

The math is beyond me, maybe someone with more experience will chime in... but here is what I can say - the taper is a constant. It's the same as the diameter of the drum. The way that the Jet manual tells you to cut the paper is to:

1) Put the taper on one end. Align the taper so it is facing outboard.
2) Roll the paper onto the drum as usual. When the edge of the paper meets the opposite edge of the drum, mark the paper.
3) Take the paper back off and make a taper going the opposite direction starting at the mark you made in step 2.

If I did exactly that with the 2 3/4" paper the end of the tapered cut did indeed land right at the end of the drum. But
the attachment clip was on the opposite side of the drum! Try it with a roll of paper cut to 2 3/4" on your drum. If it lines up you're golden. If it doesn't you can do all the same mental gymnastics I did to find out the magic ratio. For my 16" kit was 2 1/2".

Here is a great video where Susan Gardener gives us all the details on how to create the template. This method works absolutely perfectly if both attachment points are on the same side of the drum.
http://www.youtube.com/watch?v=RpfCSz9HwKU&t=510s

The Jet (and I suspect others) the attachment point is on opposing sides (not ends, of course its opposite ends ) of the drum. This means that the width of the paper becomes important so that the correct number of wraps lands you at a point where the taper doesn't fall short of or overlap the attachment insert.

Words are failing me here. It's maybe time for a video. But try it with some roll paper and you'll see what I mean.

Hope some of that helps.

Brad

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Thanks Brad. I'll give it a try with some paper.

If you own at least one roll of pre-cut paper that fits your sander, wouldn't it be easier to just lay the pre-cut paper over the uncut paper, trace it's profile onto the uncut paper, then cut on the lines?

That only works if the precut paper is the same width as the Abranet, which it isn’t.

The Abranet comes in funky widths. All the pre cut drum sander rolls I have seen come in paper that is 3” wide.


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Yup. That's the way to do it when the rolls are the same width. When they're not, I was thinking that you could just do essentially the same thing. You'd end up with a different included angle because the base of the right triangle was different, but the hypotenuse of that triangle would still cover the edge and the spiral would follow the new angle. But I was wrong, as Brad knew, having already tried the experiment.

I don't see how an odd width abrasive strip could work. Maybe I'm just being dense (again) but now that I've tried it and seen what Brad was talking about I see it this way: obviously the circumference and length of the drum and positions of the clamps are fixed. If the drum is e.g. 16" diameter you need to cut the starting edge of the strip to a form a triangle with a hypotenuse 16" long so you can cover the edge of the drum with the first wrap. There is only 1 right triangle with the given base (width of strip) and hypotenuse (drum circumference you need for the length of the edge). OK so far. Then you wrap the stuff around the drum. Fine. You cut the other end at the same angle and it wraps neatly around the drum. Also fine. But it ends in a spot along the circumference that is not where the clamp is because the strip didn't use an integer multiple of the same number of wraps to cover the drum.

I guess it would work if the strip's width is an integer multiple of the original strip, like 1-1/2" or 6" to replace the original 3" strip.

Maybe you could probably also play with non-right angle triangles, cutting sort of an arrowhead on the end of the strip until you found a winding angle that made your new strip width land on the clamp location. Sounds like a PITA to me. As Brad said, there's a mathematical solution to this but I seem to be too dense and too lazy to figure it out.

Now that I said that I'm cursed. I'll probably lie awake tonight thinking about this.

Oh man.... Bob, I'm with you, brother!!!

What I can tell you is that a 16" drum is covered by a 2.5" width just perfectly with a 16" long taper. I only know that because I cut up my roll of brown craft paper and experimented with it. I had the wife down in the shop too. Actually, she is the one that got close on the math and recommended 2.5". But afterward, neither of us really, truly, knew what had just happened.

I feel like it has to do with the 8" of extra distance between the clips because they are opposed, but couldn't figure out how to plug that into the formula.

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One thing you can think about is this... it's obvious, but it helped when we were experimenting...

Assume the diameter of the drum is 16". You cut the taper so that it is 16". As you wrap a 2 3/4" paper around what you notice is that wrap #1 is 1/4" short of where the 3" paper fell. Wrap #2 is 1/2" short of where the 3" paper fell, etc... until you get to the other side. In my case I think it was 5 wraps and what I was left with was 1 1/4" short of where the 3" paper would have met the end of the drum.

So in the case of 2.5" paper width the first wrap was .5" short. The next was 1" short. And of course the 5th was 2.5" short. Which means I could now get a full 6th wrap. That made it all line up.

Now... how do you extract the formula from that.

I swear there are some smart pants members here just laughing watching as the trained monkeys mash the typewriter trying to pound out Shakespeare.

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Trained? My wife thinks I'm barely housebroken.

It should be a total of 9 wraps to cover my drum with a 3" strip. With a 1/4" shortage per wrap that means 2-3/4 paper would come up 2-1/4" short at the end, not quite enough for a full 10th wrap to end at the clamp location. So neither of the Mirka rolls will work very well, without a lot of waste. I might still make the switch at some point though. It sounds like the benefits are worth it.

Yep, with 9 wraps I think you'd be better off buying the 4 1/2" stuff and trying to find something to do with the extra 1 1/2".

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Tape is your friend.....
My old fingers can't work those stupid clips that don't really hold the strip in place at the far end of the drum. I usually just run a piece of strapping tape around the last inch or so of the sanding strip and drum. You don't have to worry about where the strip ends. Unless you really need that last bit of width it could be a non-mathematical solution.

bcombs wrote:
"Yep, with 9 wraps I think you'd be better off buying the 4 1/2" stuff and trying to find something to do with the extra 1 1/2"."

Couldn't you rip the whole roll to 3 " and then wrap the drum with 1 1/2 inch strips that are twice as long?

I asked my question about tracing and cutting based on the assumption that the new, uncut paper is wider than the pre-cut paper, not narrower. If it is narrower, then I can see it being a real brain-teaser, and I would not try it. If it is wider, then just cut it to fit the pre-cut paper, and use the offcut for some other tasks.

All of this has convinced me to stick with pre-cut. I already own a fair amount of it, and it works fine.

I have bought 6 inch wide cloth backed rolls and they- ripped - to 3 inch widths once you got them started, no need to cut them to width.

YeaH. Right on both counts. The 4-1/2" roll ripped to 3" would leave a 1-1/2" roll that would be just as useful. Thanks for pointing that out.

And I kinda like the tape idea. I might have to try that out sometime.

Soundls Mirka and Jet ought to sit down at the table and talk

As for planers, I too have watched a nice set of Imbuia turn into wood chips when going through the planer on a backing board. I used to use CA to tack it to the board too. 90% of the times it works well enough but boy when it doesn't....

I think If I had to cut the roll, that would be a non-starter for me. Seems Mirka would know better. Any of you with 22-44s had to do that?

Abranet sounds like the way to go... its just the standard stuff you use?

What is the difference with abranet max?

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Looking forward to hearing more about the 22-44 OSC, Woodie...

i second on the abranet. the best thing i´ve put on my drum sander. lasts forever. didn't´t have any problems with stretching.

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What grit are you using? Are you cutting out like Brad?

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Pat

Any width would would work on any drum so long as you know the cutoff angle on either end. If Abranet cared, they would provide templates. Or premark. Like klingspor paper does. It’s not rocket science. Well, it is math.

You should not have to trim a roll. Here are some thoughts: http://www.sawmillcreek.org/showthread. ... nder-Paper

The string around the drum is the best idea

The idea is simple. Wrap a string around drum to get exact circumference. Place string on end corner of paper, stretch across till u intersect side. Mark. That line is ur taper on one end. Cut it. Put in drum sander and wrap to other end. Mark point on edge where paper starts going over edge. Remove paper. Use that mark and string to lay out taper on that end. Cut, reinstall. U are done. Random widths do not matter. Still, you’d think they would tell u this.

"Random widths do not matter. Still, you’d think they would tell u this."

Until you go to put it into the tensioning clamp and find it's not where the end of the strip is.

Yeah, Mike. It’s not just cutting the tapers. Do the roll paper test and you’ll see what I mean.




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