Ideas concerning grinder drum details...

[ucki]

Hi i was just wondering that has anyone here tried to replace the sand paper with for example , epoxy-SiC paste, i think it would be a lot more cost effective, i just found a site that sells SiC powder in 500g bags for just 7 euros, that amount of 80 mesh powder would last a long time, and you could glue several layers on to the drum, two or three millimeters of that stuff would grind for ever... and it would look a lot more industrial
The only problem would be choosing the correct epoxy resin , because there is lot's of differences between them, and i doubt the manufacturers would give away their secrets.... Reason why i am considering this is my concern regarding the performance of the tape i would be using to attach the sanding paper to the drum in cold and wet condiions it would be put through

[Leander]

Nice idea, maybe you can post some pics. I've grinded aluminum with a 200 grid beltsander, and lots of lubrication (mineral oil). Rougth Grinding media accually word fine, if you do it the right way. To get Al-powder of reasonable quality, you'll need lots of lubrication, and only a slight pressure against the sandingpaper, or in your case the drum. Them powder is useful for thermite, and slow report compositions. It's not gonna give you a hell of a flash, but it satisfied me...

What i would do if i where you: 'Coat' your drum with rubber. When you attach the sanding paper, if will be allmost impossible to move, when rolled tight. The other advantage, is that you dont have a really stiff surface anymore, making the paper more durable.

[ucki]

To be exact i wasn't going to use an actual "paper" sand paper , it's really a cloth or textile backed stuff...
I guess i could coat it with self-vulcanizing rubber of sorts... my concern is that ,when i increase the outer diameter of the drum i also would increase the tangential velocity(?) (can't be bothered to check if that's the correct term) which would lead to splashing the coolant water all over and making a mess of the damn thing..
Well i'm going to the school next week, even if it is winter break and i'm gonna build the feeding mechanism for the grinder and i'll try get started on the outer casing..
I'll try post pics for this post if i'll try to coat the drum with corundum or with some other grinding media...

[Blackwolf]

I have seen 2 industrial drums that were removed for maintenance. One was about 50cm in diameter and had files mounted parallel with it's axis around the entire drum and the other was about 25cm in diameter and was in effect a rotary file engraved 45 degrees to it's axix. In both cases they had steel wire brushes mounted on the bottom to keep them cleaned.
I can't remeber if they used water or something else, but when they processed the aluminium powder the would first run it past magnets to pick up any chips or wire brush bristles that had broken off, and then seived it for sizes.