DIY grit-covered feed rollers

[greybeard]

I'm planning to use a powered feed roller for the x-axis drive, and would like to hear anyone's experience with the diy construction of a grit covered roller.

In its first build it will be moving 8"wide x 36" long x 1" thick material, which will be supported on an air bed each side, but when developed, it will be upgraded to move material 24" wide x 72" long.
1" diameter pressure rollers spaced 6"apart on top, parallel and either side of the cutting area, with a vac/brush dust removal between them.

The drive roller needs to be 2-3" in diameter, and 10" long to start with, later version 26" long.

There seem to be at least 4 approaches : -

1. start with an existing metal roller and coat it with an epoxy/sand layer - no seams, good, but needs lucky find.
2. Ditto roller, but with spiral wrapped sanding belt, secured at each end - must be bidirectional.
3. Make the roller from laminating a set of wooden discs, then cover it as in 1. or 2. - needs lathe to true up the surface.
4. Run steel shaft through pipe with wooden end blocks inside - trueing up ?

Further ideas/ comments/ experience welcome.

John

[martinw]

I'm planning to use a powered feed roller for the x-axis drive, and would like to hear anyone's experience with the diy construction of a grit covered roller.



Further ideas/ comments/ experience welcome.

John

Dear John,

I'm not sure if this will be any help, but there is a Fine Woodworking book by the Taunton Press called "Making and Modifying Machines". Here is a link..

http://www.amazon.ca/Making-Modifyin.../dp/0918804434

I do not have my copy to hand right now, but I'm pretty sure that it contains details of how to make a timber-based drum sander with spirally round abrasive roll.

This might possibly of interest to you.

If you let me know your address on the private message facility, I could post you my copy on loan.

Best wishes

Martin

[HuFlungDung]

In the event of slippage of a rigid grit covered roll, it will likely sand a gouge in the part. How about a urethane rubber covered roller?

Another process which I could call DIY, because I run a well equipped shop would be flame sprayed tungsten carbide bearing powder. Usually a flame sprayed (also called metallized) surface is machined smooth after application, but in the as-sprayed state, it is rough as 100 grit sandpaper.

[martinw]

In the event of slippage of a rigid grit covered roll, it will likely sand a gouge in the part. How about a urethane rubber covered roller?

.

They make rubber covered rollers, complete with bearings, in all different diameters and lengths. They are used for material handling conveyors. I do not have prices for the rubber covered ones, but zinc plated steel rollers cost approx. as follows

40mm diameter, 200mm long..£10

40mm diameter, 650mm long,..£14

Regards

Martin

[greybeard]

Hi HFD. I like the sound of a tc grit. Should get a really good grip of the timber.
It reminds me of those abrasive metal discs that seemed to have "weld spatter"(if that's the right term) all over them. Designed to fit into a power drill and give a long lasting coarse sanding disc.

Hi Martin.
Thanks for the offer of the book, and I'll bear it in mind should I opt for that method. I've seen just that sort of approach on a web page somewhere when I was first researching the options, and it confirms that at least the idea has legs.
I must pay a visit to my local agricultural engineer(blacksmith). I've seen conveyor systems in his yard.

Regards
John