problem with sharp edges from barrel tumbler.

Hi, I would be very grateful if someone could help me! I am new to using a barrel tumbler ( I have the cookson gold pro max starter kit which came with mixed shot). I am finding that the edges of my pieces are coming out with burrs and sharp edges on them. I am putting them in as nice smooth rounded edges and they are coming out looking sharp and horrible! I then have to file them round again. This is mainly happening on pieces that I am making using blank stamping discs. I have attached some photos of before and after going in the tumbler incase this doesn't make sense. Apologies for awful photos but I think they just about show what I mean.I have tried using barrelbrite and washing up liquid and its the same problem with both. I can't work out how to stop this happening, any help would be hugely appreciated...

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This complaint has never come up before and if you read the reviews on Cookson's site, there are no comments to this effect.

That doesn't mean you are wrong, but only that your case needs careful study.

The possibilities in order of likelyhood are:

1. That your disks are not sterling, but some very soft or plated metal.
2. That there are very jagged pieces of shot in your mixture. (Most likely sharp satellites which can be sorted and taken out or filed smooth)
3. That you are not using enough solution to cover your piece before tumbling.
4. That you are going on far too long. About 3 hours should be enough.

Apart from that, I am out of ideas, but you might alert Cooksons. Dennis.

Are you sure the edge is not there before you tumble them.
I'm not sure what I'm looking at in the photos, but to me it looks a bit like the edge burr which is pushed up when punching metal and the fit between the two parts of the punch is a bit slack.

There's a burr coming out of the hole to the RHS of 'L': is that what you mean?

If so, then in all likelihood, this may have been encouraged out of the hole by tumbling, but would have existed within the hole beforehand. Better out than in as they say since you can do something about it rather than find out that daily wear has resulted in the burr coming out of the hole and prickling your customer. There's no mechanism that I'm aware of or can think of in tumbling for burrs and sharp edges to be created.

I suspect that what you're finding coming out is what went in.

Firstly, thank you all for getting back to me, this is driving me mad and so good to be able to get some help. I know this problem has never been asked before as I can normally solve any of my problems by trawling the internet for hours and this is the first time that hasn't worked and I have had to join the forum!

Its definitely sterling that I am using, this is happening after only 45 minutes of tumbling and i am using enough water in the tumbler.

The photos are trying (and failing) to show the rough edge that is all the way around the edge of the disc after it has been tumbled. As you know, when you make a disc using a disc cutter ( I have made my own and bought pre cut from cookson and am having the same problem with both), you get one nice rounded edge as its cut and on the reverse you get a burr rougher edge...well after my pieces have come out of the tumbler, both sides look like that...both are rough and have a burr and the rounded edge that was previously on one side has gone.

I thought that the rounded edge that is created when you cut the disc didn't need much more attention as it is already smooth...am I just not filing and sanding the edges enough before I tumble them?!? If not, how exactly would you recommend I do that without scratching the surface much?

Or perhaps this is just a problem with cheap shot?

Thank you!!

IMO discs always need their edges rounded off, whether you buy them or make them. The act of cutting them will always leave an edge. You will just have to sand or file, going down the grits until nice and smooth. Personally I always like hand finishing - it's nice and quiet:)

I don't think it's anything to do with the shot. I agree with others that the slightly raised edges are probably there all along, and tumbling is simply showing them up more as the piece gets shinier. There isn't anything in the process that could create the effect you're seeing - especially not after such a short time.

I cut a lot of discs, and always have to do a bit of finishing on one side. I tend to use a micromesh buff stick for this - just the two finest grades, one to knock the edge off, and the finer to smooth it to slightly rounded. With a bit of practice, you don't even touch the main surface of the disc. Without teaching any grandmothers, it's important to check that your punch surface is smooth, and using a bit of burr life (or equivalent) on the edges can help minimise the burr.

You may find it easier to cut and finish the discs before you stamp and assemble them - it's much easier to get a good final polish when there are fewer little nooks and crannies to get into and you can always pop the finished thing back in for an extra 20 minutes at the end of the process if you need to.

As for timings, like Theresa, I'm not good with too much noise, so I tend to tumble most things overnight (when I'm nowhere nearby, and certainly never for less than two hours.

Hi,

I'm having the exact same problem! I've also struggled to find anything online to help. Did you manage to find a solution? It's happening to every piece I put into the barrel polished and I always file the edges before they go in.

We would all like to know the answer to a problem which has only arisen with this barrel. Time for one of you to talk to Cookson. Dennis.

I cooksons a call this morning and they just said they will look into it and they'd never heard of the problem before.