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Matt Benton
09-20-2007, 2:55 PM
I am building a drum sander and need advice on one aspect of the construction. I am using 3" PVC for the drum, and need to figure out the best way to attach the pipe to a 5/8" steel rod running through the middle. I'm planning to use wooden discs inserted into each end of the pvc, with a hole through the middle for the rod, but how to attach the rod to the discs?

I thought some kind of flange, but don't know where to look...

Any ideas?

Thanks.

David Duke
09-20-2007, 3:03 PM
I really don't think your going to have any luck at all using PVC for the drum, first off it's not stiff enough your going to get a tremendous amount of flex through the length of the drum. Another issue will be heat, as you know PVC is plastic.......plastic doesn't do to well when subjected to heat and you will be generating a lot of heat while sanding because of the friction of the sandpaper turning against the stock

Matt Benton
09-20-2007, 3:10 PM
David,

Thanks for the response.

Actually, I'm replicating the sander that Stockroom Supply sells. Their design doesn't put pressure on the drum, and heat buildup is minimal, at best.

Looking at the 2' piece of schedule 40 PVC I have, it seems extremely ridgid.

CPeter James
09-20-2007, 3:23 PM
Not to be a wet blanket, but as the owner of a Performax 25X2 drum sander and having had a fair amount of experience with fine tuning it, you are wasting your time with PVC. Better to make the drum out of multiple MDF disks guled togehter on a steel rod and then true it up on a lathe. I have about .004" runout on one end of one drum and it is noticable. You will not be able to control distortion to those limits with PVC. Also you need some mass to control vibration and prenvent bouncing, the sold MDF drum will help with that. For a shaft, I would use at least 1/2" or better 5/8" or 3/4" turned down to carry the bearings. The bearings need to be a tight slide fit to gentle press fit.

CPeter

Matt Benton
09-20-2007, 3:59 PM
Thanks for your reply, but again, I would contest that this sander is a significant deviation from the typically thickness sander, in that there is virtually no force applied to the drum itself.

I agree, I would never consider PVC if I were planning to pass the workpiece between the drum and a fixed surface.

If you have a chance, please take a look at their website and let me know what you think...

Thanks!

David DeCristoforo
09-20-2007, 4:23 PM
If you have a chance, please take a look at their website and let me know what you think...
Thanks!

Looked at it. You still have to press the stock against the drum so the drum is still going to be subject to heat. PVC is a poor choice. If you are wedded to using PVC, you might consider filling it with cement. You could plug the ends with wood disks with your axle in place and pour the cement through a hole in one of the end caps. But. really, you would be better off to come up with a steel drum for this.

Matt Benton
09-20-2007, 4:49 PM
Thanks for all the help!

If I were to use mdf disks glued together, what adhesive should I use to secure the mdf drum to the rod?

Bill Wyko
09-20-2007, 5:52 PM
I might suggest having someone turn you the whole enchalada on a lathe.:)

Matt Benton
09-20-2007, 5:58 PM
I feel confident gluing up the disks and truing the cylinder, just want to be sure I secure it to the rod properly...

Cliff Rohrabacher
09-20-2007, 5:59 PM
I really don't think your going to have any luck at all using PVC for the drum, first off it's not stiff enough your going to get a tremendous amount of flex through the length of the drum. Another issue will be heat, as you know PVC is plastic.......plastic doesn't do to well when subjected to heat and you will be generating a lot of heat while sanding because of the friction of the sandpaper turning against the stock

What he said. PVC gets really soft at very low temperatures.

Other materials might include wire mesh reinforced Concrete.

Lots of guys make disks from MDF and stack them and epoxy them on a shaft to make a drum.

josh bjork
09-20-2007, 6:03 PM
Just rough the rod up with 60 grit and use epoxy. I did build a drum out of pvc and it did get hot and you could tell it was mushy. You could true up a wood one with a jig and a router. You can balance it too.

joe greiner
09-21-2007, 7:56 AM
I'd suggest using a newsprint core instead. Four inches OD, about 25 inches long, wall thickness about 1/2 inch of very, very robust cardboard - almost Masonite. Has metal end hubs 3 inches ID with a notch to engage the driver. Our local rag puts about 30 or 40 of them, with about 1/4-inch thickness of paper remnant, on the loading dock every afternoon for free pickup. Some newspapers charge about $2 for them, but still a bargain. YMMV.

Cut plywood disks with ears to mate with the notch, and mount all on stout all-thread as already discussed.

Joe

Phil Thien
09-21-2007, 8:21 AM
I think the point missed by many is that hundreds if not thousands of these sanders have been built by users the world over. The PVC works. It has already been demonstrated.

Bruce Page
09-21-2007, 3:03 PM
I think the point missed by many is that hundreds if not thousands of these sanders have been built by users the world over. The PVC works. It has already been demonstrated.

It would be interesting to see a poll reflecting the number of “satisfied” owners out there. I have never read any posts praising the system; it seems like a make-do setup.
JMHO and I have watched the videos.

frank shic
09-21-2007, 3:17 PM
hey matt, let us know how it turns out, ok? i've been looking at one of those stockroom supply sanders with a bit of interest!

Matt Benton
09-21-2007, 3:38 PM
I think I'm starting to question what I can do with a design like this. It looks as though it doesn't provide much more capability than a ROS, other than maybe edge sanding, and even then, it can't provide a straight edge for jointing.

As a general cabinetmaker (as I someday hope to be), would I be better off building a traditional sander with a top-mounted drum?

Thanks again for all the replies.

David Duke
09-21-2007, 3:48 PM
Matt, in my humble opinion (and take that for what its worth), I believe that you would get a better machine at or about the same price as you could build one. Not new maybe but if you take your time and look for a use one I would bet you could find a Performax 16/32 or even a 22/44 or equivilant for less than 500.00. You may just be wanting to build your on machine if that is the case go for it but if your wanting to do cabinet work instead just keep your eye out and I'm sure you will find something.

Steve Mcmahon
09-21-2007, 3:51 PM
NOT MINE

http://cincinnati.craigslist.org/tls/427478885.html

Performax Sander - $450

Reply to: sale-427478885@craigslist.org
Date: 2007-09-20, 2:50PM EDT


This is a Performax 1632 plus sander about 5yrs old, includes caster set.
Has not been used more than 20-30hrs. In good condition.
For more info please email at skwarrington@fuse.net
Local pickup only

Jim Kountz
09-21-2007, 5:01 PM
If everyone who responded would actually go watch the demo for the sander the OP is talking about you would understand why heat is NOT an issue for this machine and why PVC does in fact work for it. This is nothing like your regular drum sanders. It really doesnt do what a standard drum sander does, nor the way a standard drum sander does it. That being said I do agree with the folks who suggested searching for a used or reasonable priced drum sander for the OP's intended use.