Drum Sander Project (in progress)

[ragswl4]

After doing tons of sanding with a ROS and Finish sander I wanted to find an easier, faster way to sand. After some research on the Web and looking at the V Drum Sander Kit (too pricey for what you get, IMO) and some other plans I decided to try to build my own. The picture is the progress so far. I now need to build an enclosure for the sander and add the velcro matting and sandpaper. The drum is 18" wide. This is what I have purchased so far:

1. 3/4 HP motor from HF-$50.00
2. Two pillow block bearings-$10.00 each + shipping from Surplus Center
3. Two pulleys (5/8" and 1/2")- $4.50 each from Surplus Center.
4. 2 1/2" PVC pipe from Lowes- $4.00
5. Epoxy Glue from Lowes - $4.00
6. 1/2" steel shaft from Lowes-$6.00
6. Scrap MDF
7. Belt-just laying around.

So I have about $100 in this so far. The picture is my set up to see if the drum would spin true without a lot of wobble. I cut two round inserts from MDF (1 1/2" thick) and epoxied them into the ends of the PVC. This was the most difficult part as the 1/2" hole in the MDF for the shaft had to be dead on. During the trial run it appears I was able to achieve that as there was no noticable runout on the drum.

Next is to build an enclosure for the motor and drum and make a top. Also I will install a switch for the motor and a fitting for connection to the DC. This sander is not intended to be a thickness sander, although it could be if I so desired. Just a matter of where I locate the drum. As the design is copied from the V drum sander, the drum will be mounted under the table top.

I do still have concerns about the drum. I am not sure it will be rigid enough and of course once the velcro mat and sandpaper is installed I hope that it runs true enough to provide even sanding of the wood. More to come as this progresses.

[JR]

Very interesting project, Rags. I look look forward to your report on how the PVC holds up. I'd think it might be prone to warp when it heats up.

How do you plan to do height adjustment?

JR

[ragswl4]

You are right, the heat is another concern that I have with the PVC. However, if I am successful in duplicating the V Drum sander and if you can believe their hype, heat is not a problem. They say that their design with the velcro mat and hook and loop paper the top of the drum with the sandpaper on it should be at the same height as the table top. When turned on the air flow causes the paper to rise just a bit and with the air between the paper and the mat, the drum stays cool. Sounds good, but..... Time will tell. At least the PVC is an inexpensive part and I may have to make a drum from another material. Probably MDF discs if the PVC doesn't work.

As far as height adjustment, as the drum lies under the table and the wood passes over the top, the height adjustment will be made by moving the table up and down. I have not yet decided on how I will do that but have several ideas. I have no problem adapting as I go and view failure as an opportunity to make it work better.

I am now trying to decide how long to make the table. Most of what I will be sanding will be around 3-4 ft with the drum in the middle of the table. I was thinking 4 ft for the table length but then that.s getting pretty large and will hog up a bunch of space in the shop. Maybe I'll make some detachable wings like a planer has. Right now I'm just having fun with it. Still might make it a thickness sander. Taking a break from cabinet building. Still planning..............

Love to hear any ideas you may have, especially about a better drum design.

[JR]

Love to hear any ideas you may have, especially about a better drum design.

It would be more convenient for me if I could just tear down your ideas!

How about a turned hardwood drum? I'd think it would hold up better than the PVC (assuming the PVC becomes a problem). The rod wouldn't necessarily have to go all the way through. It could go in a few inches and be fixed with a set screw.

I don't know about the height adjusting mechanism. Probably beyond my limited vision.

JR

[eddy merckx]

What if you filled your PVC drum with something like cement. It would create a heat sink as well as adding weight.

Eddy

[ragswl4]

It would be more convenient for me if I could just tear down your ideas!

How about a turned hardwood drum? I'd think it would hold up better than the PVC (assuming the PVC becomes a problem). The rod wouldn't necessarily have to go all the way through. It could go in a few inches and be fixed with a set screw.

I don't know about the height adjusting mechanism. Probably beyond my limited vision.

JR

Here is a link to what I am attempting to duplicate. This should clarify what I am doing and also define the type of sander I will most likely end with. There is a video link on that sight but not a great one. Also the V Drum Sander uses a poly carbonate drum so it might be that this design overcomes the heat issue with the drum.

http://www.stockroomsupply.com/V_Drum_Sander.php

I like the idea of the turned hardwood drum. It would seem that would be more stable and add some weight which may in fact be needed. As I don't have a lathe that is not an option for me right now. (maybe a reason to get a lathe, though).

[ragswl4]

What if you filled your PVC drum with something like cement. It would create a heat sink as well as adding weight.

Eddy

Thanks, I'll will keep your idea in mind as this progresses and if heat/weight becomes an issue. It has been an adventure trying to find a drum for this project. I gave up and decided to just make one. PVC is probably not the best for this but its inexpensive. I don't mind making changes if it doesn't work.

[JR]

Well, now that I've seen the videos I have a much clearer impression of what you're trying to do!

I can see that as long as you're using it as a sander, and not a thicknesser, things are much simpler. The heat buildup is said to be much less in the sander mode as the paper is "flying" off the drum.

Height adjustment for sander mode shouldn't be too complicated. A couple of t-nuts and some threaded feet should do the trick. Hinges on one end of the table, with t-nuts under the other end (attached to the drum/motor assy. frame), would give you the fine adjustment necessary. Maybe some reinforcment of the table would help keep it all straight.

As to your space concern, I noticed their recommendation that you embed the assy in the outfeed table of your TS. I thought that was a good idea.

Great project, Rags. Good luck.

JR

[ragswl4]

Thanks and also for reminding me about the outfeed end of the table saw. In fact I was thinking of making an outfeed table for the TS anyway.

[hermit]

Wow, that seems like an ambitious project. Reminds me of my DC building period. Good luck, I'll be watching to see how this turns out.

Todd

[blame]

looks like a great start rags i cant wait to see how it turns out completed

using pvc for the drum i would think it would flex to much to keep a strait sanding profile
i would try the same meathod you used but with a piece of steel pipe. i dont think it would be any more expensive for the steel pipe. i would look for the thickest walled pipe you could find. just my 2 cents

blame

[ExYankee]

I'm glad you are doing this, I have been considering doing something along these lines. I was thinking that if you drill a pattern of access holes into the drum and shot in Great stuff the expanding foam would provide added rigidity. The "over the top" type sander doesnt seem to build up heat since there is little torque on the drum.
putting it the outfeed table is a good idea, if you made some sort of tension release on the belt it would also serve as a stock roller.

Keep us informed of progress please.

[ragswl4]

Drum Sander Update

Here is the progress so far. Enclosure is on. I elected to mount the motor outside to keep it free from sawdust. All mechanical in done and except for the motor running the wrong direction it functions as I had hoped. Motor can be reversed so no big deal. Need to mount an on/off switch, add some trim to the top and wait for the Velcro and sandpaper to arrive.

Making the top turned out to be easy. Routed out the opening with a 3/8" bit and then chamfered the bottom of the opening to give clearance for the drum. Had to make a clearance slot for the belt. When the sandpaper arrives I can give it the real test. I still need to add height adjustment for the top but will do that when drum is loaded ready to sand.

At this point I elected not to add to the table saw as an outfeed table until I see if it works as expected (More like Hope).

[JR]

Looking good, Rags!

[Thom2]

I like the idea of the turned hardwood drum. It would seem that would be more stable and add some weight which may in fact be needed. As I don't have a lathe that is not an option for me right now. (maybe a reason to get a lathe, though).

just FYI: you don't need a lathe, you can BS, holesaw, circle cutter, anything to make discs close to final size. Glue the discs up and then mount it up without sandpaper. Use a flat panel with sandpaper attached to shape to final size.

Or, if you don't wanna glue up (I'd prefer glue-up as more end grain area will take a beatin' more as well as less movement from heat/humidity etc), use the TS to knock corners off until it's 8 sided (or more if you feel adventurous), then do the same thing as above with a panel and sandpaper to shape it to final size.

Looks great so far tho', my only concern would be that PVC