Looking for advice on magnetic tumbler

[Ainamo]

Hello,

I am new here, so nice to meet you all!

I'm looking for advice on a magnetic tumbler (Avalon PM200S) that I bought recently. I've tried the tumbler a few times now, and the results have been really disappointing:



This cast silver piece in the picture is an example of what I'm trying to finish. With the tumbler I'm trying to get the silver even in color without any/hardly any residue from pickling. So my only goal is to get the silver clean. To my understanding magnetic tumbler is perfect for metal with hard to reach corners, just like this piece (the narrowest grooves shown in the picture are about 1,1 mm). I've had good results with Otec magnetic tumbler (with 0,5 mm pins), but a $6000 machine is not an option for me right now.

The Avalon tumbler came with "Vilux" compound and steel pins in two sizes, 0,3x5 mm and 0,5x5 mm. I've carefully followed the instructions and used 60 g of steel pins with 500 ml of water and 5 ml of liquid compound. The pins were cleaned prior to use. I've run the tumbler 10 minutes at a time, trying different speeds and both pin sizes separately. But even after 1 hour of tumbling the same piece the result is still uneven. I would've thought that 0,3/0,5 mm pins could reach 1,1 mm grooves just fine!

I've run out of ideas, so if anyone can think of anything that might help, please share your thoughts!

[josef1]

I would run it at the fastest speed with the smallest pins for 3 to 4 hours or sometimes even longer . Also stop the machine every once in a while and manually turn the parts over you should get a good finish then

[ShinyLauren]

I usually run mine for around a half hour (I have this one: https://www.hswalsh.com/product/mini...polisher-tp300). I use a mix of the fine 5mm pins and tiny ball bearings and usually get a really good finish. I agree with Josef to manually turn the bits half way through, as sometimes they get kind of stuck and one side won't be polished at all.

[Dennis]

This piece is simply not being polished and my impression is that it is either too bulky for your machine (does it weigh more than200g as specified, or occupy a lot of floor space in the pot?), or it is being dragged by the chain.

Two things to do before you try again:
1. Remove the chain.
2. Brush the piece with a soapy brass brush to clean it overall and brighten the recesses with a pencil sized glass bush, if they have proved too deep or detailed to reach.

Then hopefully it will stand a chance. Dennis.

[Ainamo]

Thank you all for the tips, I really appreciate it!

Josef1 & ShinyLauren​, this specific tumbler is designed to do its job in 20-30 minutes, so 3-4 hours would be a too long time for tumbling. Also, during the tumbling process the pieces turn around on their own, so both sides get polished, but only from the surface, not from the grooves.

Dennis, the piece in the picture weights 3,7 g and the whole thing with the chain and other parts weights 21,5 g total, so it's definitely not too heavy for this tumbler. The bowl is 17 cm in diameter and the things I've been tumbling are somewhere around 30x50 mm. I always use brass brush with soap after pickling, but it only helps to some extent. After tumbling the outer surface looks polished on both sides, but it's the (even remotely) intricate parts that are left unfinished. I've tried several pieces with this tumbler that differ in detail, size and weight, but the results are still the same.


It might be that my copy of this tumbler is somehow faulty, because I've worked with Avalon tumblers before without any problems. I'll report back when this issue is solved!