rubber sanding drums

williwaw · February 22, 2021, 07:22:00 PM

so I was about to order some belts from supergrit and was looking over their selection of rubber sanding drums and sleeves. (the expanding type and not pnumatic).

I hope to set up to grind some lams and was thinking maybe larger diameter might be better. They sell up to 4" diameter. On second thought, I wonder if a large diameter in a rubber drum could be problematic with runout or out of roundness, and if I would be better served with a more ridged drum from a different supplier?

I got my glass order, (thanks for the quick service, Kenny) and now I got to get busy with some lams. What else should I consider for tapering lams in way of drums?

Crooked Stic · February 22, 2021, 07:42:02 PM

I got a 3 inch rubber one for my spindle sander wobbly

williwaw · February 22, 2021, 08:40:16 PM

Hmm. ,my gut feeling is a more solid drum would be better. does anyone use the sleeves for rubber drums on wood or metal drums, or know who sells wood, hard plastic or metal drums?

Shredd · February 22, 2021, 08:43:27 PM

You could flatten out the inner section of the drive drum on a belt sander...

Flem · February 22, 2021, 09:39:46 PM

Those expanding rubber drums are for profile sanding, not thickness. If the rubber distorts (expands) to grip the sleeve, it's not going to be a flat surface and will make a cup or crown on your lam. Trust your gut!

Mad Max · February 22, 2021, 10:07:46 PM

x2 wif flem

williwaw · February 22, 2021, 10:26:45 PM

Quote from: Flem on February 22, 2021, 09:39:46 PM
Those expanding rubber drums are for profile sanding, not thickness. If the rubber distorts (expands) to grip the sleeve, it's not going to be a flat surface and will make a cup or crown on your lam. Trust your gut!

ok, so are there any harder drums on the market that can be used with the premade sleeves?

just trying to get something usable to get started with. I have a Jet EVHS 80 and a tool craft 6 x 48 combination sander. both tools need belts and bearings, and one will eventually be customized with a table and fence suitable for more serious lam work. I could cut plywood disks and bolt them together with allthread to chuck in to my drillpress, but I thought there might be something more off the shelf I could press into immediate service, and save the "project" for the belt sanders awaiting overhaul.

mmattockx · February 22, 2021, 11:03:51 PM

Quote from: williwaw on February 22, 2021, 10:26:45 PM
ok, so are there any harder drums on the market that can be used with the premade sleeves?

This guy uses a drum and sleeves on his thickness sander design:

https://buildyourownbow.com/how-to-make-a-simple-thickness-sander-build-along/

Can't say how it works, my sander uses a hard drum with strip sanding paper wrapped onto it.

Mark

williwaw · February 23, 2021, 01:13:19 AM

thanks Mark.

that site is the same guy, jwillis, that posted the WTT bows being discussed the other day. He explains about the issues using rubber drums and a fix he accomplished. he actually prefers the machine he built with it....

QuoteHow did it turn out? It turned out great and it works really well for making bows! In fact, it works so well for veneers and small parts that I prefer to use this little sander for making overlays, power lams, tip wedges, and some super thin veneers instead of using the large dual drum sander that I bought later.

Roy from Pa · February 23, 2021, 07:15:27 AM

I don't think rubber drums is a good idea for grinding lams either.

Longcruise · February 23, 2021, 09:06:42 AM

Quote from: Roy from Pa on February 23, 2021, 07:15:27 AM
I don't think rubber drums is a good idea for grinding lams either.

No, they ain't. My first drum for a drill press was made with a cutoff from a rubber spindle sander, bolts, nuts and washers. Worked fine for shaping but forget flat or squared surfaces. Bingham (and im sure others) sells a hard drum that works pretty good.

Flem · February 23, 2021, 10:22:20 AM

I think I would spend the time and energy used trying to rig up something temporary on getting that Jet sander set-up. If you are going to make a hard drum, MDF is harder and more consistent than plywood. 4" sch. 80 pvc works real good and would take a fraction of the time you would spend truing up a stack of discs.

Shredd · February 23, 2021, 01:47:02 PM

Flem how do you go about doing a 4" pvc and centering it???

williwaw · February 23, 2021, 02:25:44 PM

I found a hard plastic one made and sold in the netherlands, and the video showed how one could tru it up in a lathe if more precision was needed.......nothing but the rubber types at binghams. (Dont they want you to buy the lams from them?)

using materiels that wont warp with moisture, I suppose one could cut mdf disks with a hole saw to slip into a piece of pvc and then true the OD on a lathe. sort of like this guy here.
http://www.stallard-engineering.co.uk/Engineering/Sanding%20Drum.htm

new question, forgetting about the premade drum sleeves, and considering a roll of paper to use for gluing on to a homemade drum.
what weight paper? what grit size and type for grinding lams work best?

mmattockx · February 23, 2021, 03:21:13 PM

Quote from: williwaw on February 23, 2021, 02:25:44 PM
what weight paper? what grit size and type for grinding lams work best?

This is what I am using at the moment. I am sure many of the roll types of paper will work well.

https://www.busybeetools.com/products/sanding-paper-roll-60g-3in-x-96in.html

Mark

Flem · February 23, 2021, 04:27:51 PM

I made hubs out of 3/4" MDF discs. This drum is 18" and only needed 3 hubs to make it totally rigid.
Truing up the drum is only half the battle. You really need to balance whatever drum you make or buy. Balancing ways are fairly easy to knock together. I think I would stay away from all thread, its not made for rotational applications. Horizontal shafting is about the most reasonably priced axle material, plus its hardened.
[attachment=1]

If I had access to a metal shop I would do it over and use aluminum tube and mill a couple al discs

williwaw · February 23, 2021, 06:44:57 PM

Quote from: Shredd on February 23, 2021, 01:47:02 PM
Flem how do you go about doing a 4" pvc and centering it???

Did you make the mdf hubs with wood working tools? You must be happy with the runout, or did you have to true the plastic pipe after assembly?

Flem · February 24, 2021, 09:50:39 AM

willi, the hubs only required a 1" dowel mounted vertically on a scrap of plywood, clamped to the bandsaw and spindle sanding tables. The drum was balanced and trued. As I recall it did not require much truing, there was a slight lengthwise ridge and a corresponding flat area on the opposite side. From manufacturing maybe?

Flem · February 24, 2021, 02:27:28 PM

I've been using Red Label Zirconium, 80 grit. Its been a year since I checked, but they had the best price per sq in.
I use 3", buy the 6" roll and cut it down. Works out to less than .02 per sq in. And free shipping
https://www.redlabelabrasives.com/collections/sanding-rolls/products/6-inch-x-50-ft-zirconia-woodworking-drum-sander-roll?variant=21612082245

Mark R · February 24, 2021, 02:50:24 PM

Back in 2013 I purchased a solid carbide sanding sleeve 3/4"x2" 50 grit for a rubber sanding drum, at a wood working show, I believe it was a saburrtooth product,I've checked and cannot find it in the 2" and am currently looking for another one. I put this on my big variable speed router with a pattern bearing at lower speeds and it works like a charm for patterns and making lams. Hope I can find another one or something similar, if I do I'll share info or if someone else finds something similar I'd appreciate a heads up.