Tumbler Build - For cleaning plasma cut parts.

Its not as though the shaft will be spinning at high speed and the load will never be balanced.

Why don't you machine a flange to fit the shaft that has some bolt holes on a PCD and weld it onto the shaft? Then you can just bolt your sprocket on. Worst case, you'd have to be creative working out how to drill the matching holes in the sprocket assuming it hardened steel.

i think that sprocket is set on tapers and when the screws get tight it compresses the sleeve and tightens on the shaft. the key way is extra measures to keep things from spinning on the shaft. high speed is not the issue but driving all the weight of everything needs the key way. the sprocket design might not work well doing something like that. i think we could be stuck with the design as it is and getting the key way in the shaft. you might be able to sleeve the shaft and key the sleeve then stake the sleeve to the shaft but that all depends on the material amounts in the bore of the sprocket.

Decided not to butcher the shaft with a grinder.

Rang a local engineering workshop that does mining work and they have a mill large enough that they can fit the whole drum on it. Dropped it off an hour ago and they reckon they will have it ready to pick up at 7:00am tomorrow morning. They run two shifts so night shift will get it done.

They reckon about 1 1/2 hours to do the work at $95 a hour. Not too bad as long as they dont stuff it up.

Yeah the sprocket is a taper lock. But I tightened it up and could still slip the shaft when rotating the drum by hand. The keyway will sort that out I hope.

machinedude wrote:

another option would be something like this but they are not cheap if you would have to buy one. but you would probably get your money out of one if you run into this kind of thing often.

Thats pretty awesome. I brought a good quality magnetic drill two years ago and it was $1200 AUD. I would hate to think what that thing is worth.

But its always good to know about things like that when a big paying but technically difficult job comes up.
I have a local tool guy come see me every month and I am always looking forward to see what he has in his big van. He travels all over and carries tools and such that most people dont know about.

taking a guess at how the sprocket is made the taper inner sleeve of the sprocket probably has a slit in it for the compression movement to lock it to your shaft. since your shaft is just round stock the sizes could be on the small side and the inner sleeve of sprocket might not be able to compress enough. if the screws are bottomed out on the sprocket those might be able to be drilled and tapped a little deeper to give you some more compression and you might be able to get some more if the slit on the inner sleeve is opened up a little more. your key way will make it work regardless but sometimes when key ways get over worked they can fail. so if it is really loose on the shaft you might want to mess with it a little to see if the load can be split between the sprocket and key way more evenly so you don't have it fail faster than normal wear and tear. just some food for thought.

The sprocket is tight on the shaft but it is still moving under load. I think it will be fine with the new keyway.

looks pretty good. if it only slips under load without the key you should be fine then. you just don't want slop in the connection. that's when things get sideways on you. your build looks pretty robust so you should be able to do some serious tumbling regardless. beings that everything is low speed if trouble would start i would bet you are able to hear it before and fix things before anyways.

I reckon Stefan will be in hot demand with the local Lions Club et al to conduct their raffle draws!

Believe it or not but at least 5 people have said that to me in that last two days!