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drum sander problems(pics)
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Author:  KenH [ Sat Aug 04, 2007 6:25 am ]
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I have the Performax 16/32 sander and ever since I changed the paper on the first roll of paper that I wore out I have had some problems. I figured out that I was winding the paper backwards when I started tearing up paper left and right, but now I seem to have problems with burning the wood and also the paper loading up (see pictures)


This is 120 grit performax paper and it doesnt seem to last long at all. I loads up like crazy and burns the wood. What paper do you use and where to get it? Am I doing something wrong?




 
Author:  James W B [ Sat Aug 04, 2007 6:34 am ]
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I use 80 grit and set the conveyer belt to run pretty slow.I get a little loading and burn sometimes,but most of the time I`m okay.As soon as I notice any loading at all I clean the belt with one of those gum rubber sticks that woodcraft sells.I also have never been able to figure out which way the arrow on the back of the sanding belt goes.I assume it goes the same direction as the drum spins.Hope this helps.
                          James
Author:  KenH [ Sat Aug 04, 2007 6:43 am ]
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I have one of the rubber erasers from Woodcraft (you can see it in the bottom pic) but it doesnt seem to help.
Author:  Kim [ Sat Aug 04, 2007 6:56 am ]
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Hey Ken,

Same machine here. Some of the more oily woods will be more prone to clogging. I would only ever use 120 grit on spruce, all others 80 git is the go and if I have a fair bit to hog off, or if it is really oily wood, courser is better, even down to 36 grit to get the bulk off.

Make sure that you have very good extraction or this will cause problems as well. I also run my feed at around 70% or slower for most stuff and, where possible, feed at an angle to the grain finishing with the grain only using a few very light passes.

On that note, remember, this machine is essentially a sander and not really a thicknesser in the true sense of the word. It is meant for lite passes only. If you get too greedy trying to hog off too much at once in order to save time, you will pay. Take it steady, get into the mind set that this job needs to be done right.

If you want time savings, try using a Wagner Safe-T-Planer to get things down closer to finish thickness first and try to remember how long this task would take to do as accurately if you where doing it all with a hand plane.

Cheers

Kim
Author:  Kim [ Sat Aug 04, 2007 7:02 am ]
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There goes that Hesh dude again, waits till I go to do a post and then jumps in just before me agin. ..Well, that does it Hesh, I'm tak'in the web cam down as of now, better go git ya self a new pony fella cause this ones buck'in the system.

Cheers

Kim
Author:  Dean [ Sat Aug 04, 2007 7:04 am ]
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You need much more vacuum! The dust is going around and being compressed back between the paper and the wood causing load-up and a tremendous amount of friction heat. The cleaner sticks help a little, but once you have burnt resin stripes, games over. Then you need to buy Wurth pitch and resin remover. Put some in a coffee can and let your belt soak for awhile, take out and rinse and you will believe you have a brand new belt! I use it for my hand-held belt sander, my 16/32 and my 43" wide belt. Here's a link. Go to page 10.
 http://www.louisandcompany.com/machinery/pdf/MSF-Summe r07_2.pdf

Dean
Author:  Rick Turner [ Sat Aug 04, 2007 7:05 am ]
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The directional arrows are vestiges from using lap splices on sanding belts.   You don't need to pay attention to them on hook and loop strips for drum sanders; except in some very exotic abrasives, there is no directionality to the grit, and in fact, reversing the paper when it seems worn will actually expose fresh sharp grit.

Most of the cloth backed sanding strips and belts can be cleaned with a high pressure washer.   We do that on our wide sanding belts.   You can even take them to a car wash, though that pressure isn't generally as high as you might like.

As has been stated above, don't try to take too much off at a time.   

Run resinous woods through slightly diagonally until final very light passes.

The better your dust collection is, the less dust and resin build up you'll get...I almost can't stress this highly enough.   A lot of that is the dust sticking to the drum and then getting mashed into the crevices between the grit as the drum comes around again.
Read Sando Nagyszylanczy's book on small shop dust collection and design a "stripper"...kind of an air knife to blow the dust off the drum and into your dust collection hood.
Author:  old man [ Sat Aug 04, 2007 7:05 am ]
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I only have two grits: 60 and 100. I use 60 on oily wood and 100 on everything else. Best paper to be found, I believe, is Klingspor.


Klingspor


Ron
Author:  Don Williams [ Sat Aug 04, 2007 7:28 am ]
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Your problems are more than just one.

1. You're trying to sand deeper than you should.
Go slow, take little bites as Hesh says.

2. You're using too fine a grit for thickness sanding.
Use 120 for final sanding only, and very light passes.

3. Better dust collection will help, but it's not the biggest issue.
If you're using oily woods, and if you're sanding too quickly or deeply, the oils will stick to the paper upon contact, and they will build on themselves as the drum spins through the wood. No amount of dust collection will prevent that. It's not just that dust is recirculating and getting stuck. That drum spins very fast, and in most cases, faster than the dust can fly around it. What dust does fly around it tends to stay airborn rather than settling right back down on the wood. The buildup from recirculated dust is actually minimal compared to the drum heating up and getting a coating that builds on itself as it's sanding the wood. It's mostly a combination of heat and pressure that does it. That's one of the reasons a wide-belt sander is so superior to a drum sander. The paper and unit run a lot cooler.

As I see it, the biggest issue here is that you're trying to do the sanding equivalent of driving an Escort like a Ferarri. Stay within the limits of what the tool was designed to do, get better dust collection when you can, and you'll be ok.

That air knife idea seems like a good one. Mike Doolin did something like that with his sander if I recall, and it helps.

Author:  Don Williams [ Sat Aug 04, 2007 8:27 am ]
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Ok, I was going to save this for a later post, but I want to tell everyone a little secret I discovered a couple months back. I have this steel-bristled scrub brush from Agent Orange that is used for scrubbing concrete. It comes with a pole, which I removed. I use it to knock off the stuck-on wood and oil resins that adhere to the paper. I can go from clogged to clean in a matter of a minute or so. Anything really stubborn can get knocked off easily with a scalpel or xacto knife. If you enter from the side of the resin blob, it will usually pop right off. The brush is the real secret though, and as I said, it works very fast. Much faster and better than one of those gum eraser type deals, and it gives you the ability to leave the paper on the drum and keep using it. I tend to push the sanding a little hard at times, and if I stop and brush the paper every little while, I can sand all day. Even cocobolo...

Try it....you'll like it.
Author:  KenH [ Sat Aug 04, 2007 10:45 am ]
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I really dont think it is a vaccum problem. My house vac system will literally suck an allen wrench off of the worktable. I do, however, believe it is a problem with the paper. I have been trying to take small passes as Hesh describes (1/8 turn) and it still happens. I dont know if the wood could be some of it, but this is some curly soft maple that I am currently working with.



Dont mind the messy shop...
Author:  KenH [ Sat Aug 04, 2007 10:46 am ]
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I'll have to try some lower grit paper as well..maybe it is the 120 and 180 grit papers that is more of my problem.. thanks for the tip on some better paper!
Author:  Rick Turner [ Sat Aug 04, 2007 11:00 am ]
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Maple likes to burn. Going with a faster feed rate and lighter cuts will prevent heat buildup at the point of contact. The belts (as well as things like router bits) depend on fresh cool material to work in order to cool. Slow feed rates allow the heat to build up and once that happens you hit a kind of tipping point where the burnt sanding dust packs in on the paper and it all gets geometrically worse.
Author:  SimonF [ Sat Aug 04, 2007 12:50 pm ]
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Hi Ken,
Don't eliminate the dust collector just yet - you mentioned a "house
vacuum". What kind of dust collecting system do you own or more
importantly, how much CFM - you are going to need at least 500 CFM for
your Performax to perform as expected. A regular vacuum (nominal CFM
but high static pressure) is far from ideal.

If you have proper dust collection and take light passes with 80 grit
sandpaper, you shouldn't have much trouble.

Best of Luck,
Simon
Author:  KenH [ Sat Aug 04, 2007 1:05 pm ]
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its a 650 cfm blower system and it vents to the outside (no collection or back pressure). I think I'll switch to the 80 grit paper.


Thanks all!
Author:  KenH [ Sat Aug 04, 2007 1:12 pm ]
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I just realized that the shop vac on the floor might be misleading... i rarely use it... look above mounted to the wall and you will see the blower system I use. It is a 4" system and has a 6" exhaust that goes through the wall and into the chicken yard.


I also looked inside the exhaust port on the preformax.. there is not any kind of x brace or anything that would impede the flow of air except for the blast gate. I checked that for obstructions too...nothing there.
Author:  SimonF [ Sat Aug 04, 2007 1:18 pm ]
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Never mind then...I think the grit size is you main culprit. 80 grit will do
a much better job at thicknessing than 120 grit.

Let us know if the 80 grit paper solves the problem.

Author:  fryovanni [ Sun Aug 05, 2007 7:55 am ]
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Lots of good advise above. With the Maple. I would say you are taking too much and you are moving it too slow. Lots of vaccume is great, because it clears the dust and really helps to keep the drum cool. Keeping the material(any material) moving quick enough will also help keep things cool. If the machine bogs as you run it fast, you are taking too much. If you can angle the material that will also help prevent spot heating. Using that little eraser is nice to clean the paper, but you need to use it often before you get build up(and it does little to remove baked on resin).

Peace,Rich
Author:  Pwoolson [ Sun Aug 05, 2007 8:44 am ]
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Ken, I find that Maple is one of the easiest woods to burn. Soft Maple easier than Hard in my experience. It won't usually pitch the belt like, say, cocobolo will but it will cake it much like your pics show. Maple does have a sticky quality to it (think maple syrup) and so it is pretty easy for the dust to cake.
As said before, increase you grit size and back off on the cut. If 1/8 turn is normal, try it at 1/16 turn. And run the feed wide open. It will be slower sanding but the belts will last longer so you won't have to take a break and change them.
Author:  KenH [ Sun Aug 05, 2007 12:44 pm ]
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does anyone have a better paper (and possibly cheaper) than the performax papers that I have been using?


I noticed that the link to klingspor that Ron left was also a link to the performax paper. It is quite a bit cheaper than what I have been paying through woodcraft, but somehow I feel like there is a better paper than the performax out there??


I have had good luck with 3M papers, but so far I havent found the 3" wide rolls of it that I am looking for. The 3M papers do seem to last a bit longer but right now any long lasting paper would be cheaper in the long run.
Author:  Rick Turner [ Sun Aug 05, 2007 12:57 pm ]
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If 3M makes their purple sanding belts in something appropriate for you, try that. The stuff is great.
Author:  Doug O [ Sun Aug 05, 2007 1:04 pm ]
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[QUOTE=Hodges_Guitars]

does anyone have a better paper (and possibly cheaper) than the performax papers that I have been using?


I noticed that the link to klingspor that Ron left was also a link to the performax paper. It is quite a bit cheaper than what I have been paying through woodcraft, but somehow I feel like there is a better paper than the performax out there??


I have had good luck with 3M papers, but so far I havent found the 3" wide rolls of it that I am looking for. The 3M papers do seem to last a bit longer but right now any long lasting paper would be cheaper in the long run.


[/QUOTE]


Try these guys - http://sandpaper.com/index.asp  Their website is pretty weak, but call them and they'll fix you up.  I have found them to be sometimes half the cost of other sources.
Author:  Rod True [ Sun Aug 05, 2007 1:05 pm ]
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I get my belts from my local tool supplier. I buy 6"x80" belts for edge sanders, cut it at the joint and wrap it around my drum. I get belts which are used for metal, the heavy backed paper belts. They will easily last through 3 b/s sets if I make light passes. They are pretty inexpensive too. You can get two belts at Grizzly for $12.95.

Like most everyone else said, your using to high of a grit. I've run a bunch of maple through my sander and have never had build up even close to that. 80 grit is all I ever put on my sander. I use the ROS with 100 to get any deeper sanding scratches out.
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