Belt Grinder Upgrades- Rubber Sheathing?

Hi all,

I built a 50x1500mm belt grinder back in the summer of 2021. Recently I decided it would be nice to have a few more attachments, such as a contact wheel and a small wheel attachment.

I wasn't in a rush, so ordered a contact wheel from AliExpress, and I found a very cheap small wheel attachment on some dodgy website (Weirdly it has now been put up from £32 to £85, so I may have got it for the wrong price).

Both arrived and I began fitting them. The contact wheel was very simple to fit and I'm very happy with it.(Very mucky, it has been cleaned since)

For the small wheels attachment I decided that I wanted to put some idler wheels around the small wheels so it pinches the belt down so I can fully utilise the small diameter of the wheels.

I have made some idler wheels from some aluminium tubing and I have press fit some bearings in.

My though is, these wheels are going to be running on the outside of the sanding belt, which will likely cause wear over time. As a preventative maintenance kind of thing, it would be nice to coat them with some kind of rubber that will not wear away as quickly. Possibly some kind of tubing that I could stretch over the wheels and replace over time when necessary. I had thought about using a bicycle inner tube but there must be something more suitable out there?

Does anyone know of any suitable tubing and where to get some? Or perhaps any other alternate suggestions?

Thanks in advance

Won't the 'grit-side' reduce anything you put in contact with it into airborne particles.. ?

It shouldn't. The wheels will be spinning alongside the belt as I have pressed the bearings in, so there will be less abrasion but still some. Hence why i'd like to cover them in some rubber.

These products are usually sold with rubber wheels but are significantly more expensive. I looked into castable rubber but decided it was too messy, and I was unlikely to get it to be concentric.

On my 2x72 grinder i did buy some shafts already covered with rubber about 5mm thick a selection of diameters ( i cant remember where now though) i needed a special size so made a alloy shaft and covered it with heat shrink tubing…its worked well

Richard

Car heater or coolant hose ought to work pretty well if a suitable size can be found.

I've built softer faced rollers using both with reasonable success in the past. Albeit running on ordinary surfaces, not the business side of sanding belts

Abrasion will be very slow so long as the belt surface resilience is such that the abrasive grains "cog" into the material rather than slip. If the sanding grit slips across the roller surface it will wear rapidly. If it "cogs" into the soft faced roller it is basically just deforming it a bit around the sides of the upstanding abrasive grains so the wear mechanism is mostly due to differing shapes and spacings of the grains interfering with the cogging action.Think rack and pinion with rather worn and not particularly accurate pinion still turning easily on its bearing. Normal abrasive action is more like what happens when the pinion bearing is pretty much seized. The pinion teeth get wiped out quite fast.

Clive

How about using skate board wheels ? You may have to re-profile them to take the crown off, and fit the more up market wheel bearings.

Bob

Agree with Clive car heater hose, available in a range of sizes, I had to do a temporary repair at work where some short rollers for guiding newspaper inserts along a conveyor wore out and replacements were on back order from Germany. I used a blue silicon hose from a supplier of kit car parts Car Builder Solutions ( probably also available on Ebay), available in straight lengths, the wall thickness is more constant than the cheaper black stuff, and in this situation doesn't leave black marks on the newspaper inserts. Small grooves in the steel roller under the hose, bit like circular knurling, and sliding the hose over the roller after heating in boiling water to soften , all of the sleeves stayed on ok. Got some brownie points at last for that!. the blue silicon may be a little soft for running on an abrasive belt, the standard black hose should be ok for your application, pretty tough stuff.

If you have a Facebook account, you might consider joining Home Built Belt Grinders, and asking there too.

Bill

Thanks to all so far.

Ian- I think Heat shrink tubing may be a good idea to try out initially, but I don't see it being very hard wearing?

Clive and Dave- I think the tubing would be the best option, but I am unsure of what size would suit. How much are you able to stretch the hose? I am also unsure of the exact diameter I turned the aluminium wheels to, so I will double-check when I'm home this weekend.

Bob- I had the material for these wheels already so I just wanted to make use of it. I'm sure skateboard wheels would have worked fine.

Bill- Coincidentally I joined that group last week, it is a good resource. However, I thought I would try here first as generally, I find the people on this site to have more knowledge on things. I may try it as well and see what others think.

Another weekend spent fitting the new tooling. (and a few other minor upgrades)

Last thing left to do is to make a tool rest for it, but that will have to wait until next weekend.

I did run the sander at its minimum speed to see how it went, and it ran okay, but I still think i'd like to cover the wheels.

I measured them and they are 38mm diameter. I found some radiator tube that's 35mm ID, will this be easy enough to stretch over the wheels? I know radiator tubing is tough stuff, but after soaking in warm water, will it be supple enough?

Richard

I've been trying to remember how much radiator / heater hose stretched when I used it tyre fashion many years ago. Unfortunately the nearest thing to a useful recollection is that I made the base diameter close to, or perhaps a touch larger than, the ridge formed into the hard connecting pipe to stop the house slipping off once the jubilee or equivalent clip had been done up.

On that basis 3 or 4 mm stretch on your 35 mm ID hose doesn't seem unreasonable. Whether it will hold purely by stretch or whether it will need adhesive I know not.

One of those "tried a number of things" jobs which I was glad to see the back of and fairly resolved not to do again in future if at all possible.

Pushing heater hose in steel tubes with suitable mounts welded on as the basis for stiff hinges and home brew anti vibe efforts was a different matter. Used for a number of things and well up too the top of the "works well" list.

Clive

Thanks Clive

I think I'll give the 35 ID tube a go then. I'll order now and update at the weekend

It still hasn't arrived...

This may take longer than expected

Ended up getting a refund, and then reordering from a different seller.

Ebay says the package has arrived, so I will attempt to fit the rubber this weekend!

I bought the wrong size...

Measure twice

There are a number of suppliers that advertise in Old Glory / Vintage Spirit who apply a rubber coating to traction wheels of all sizes . Also PAR in Lancashire may be able to help . Maybe avenues worth exploring ?

Edited By Trevor Drabble on 27/03/2023 22:57:44

Finally, the new tubing arrived. 32mm ID on a 34mm wheel.

It pushed in very nicely, snug enough that I can't get it back off.

I'm very pleased with the result, now to put it to use!

Thanks to all for comments and advice

Trevor, thanks for your message, I will look into this if I need any more wheels coating in the future.