Spec me a grinder/belt for finishing aluminium.

[m_c]

https://www.frost.co.uk/motor-parts-...isher-8kg.html

I got mine when they were still £99. Not the most robust of machines, but does the job, and was the cheapest tumbler I could find that would handle reasonably sized parts, without spending 4 figures on an industrial machine.
The media is very expensive from Frost though. The last batch I got was from Moleroda (https://www.moleroda.com/product-cat...and-compounds/), but have a search.

[JOGARA]

Hard to tell how big it is without seeing it. Do you know/think it could take the size of the part I am working with?

[m_c]

Quite big!

From the description-

The drum opening is 10-1/2" in diameter allowing the easy addition or removal of items

I'm about to head to the workshop so can get some accurate measurements, but it's about 18" tall, and is currently sat on my 12x18" granite surface plate.
It'll easily handle those size parts, but it'll takes a fair bit of media. Just checked my last order, and it was for 5kg bags, which give a reasonable level in the bowl.

[JOGARA]

Okay that is pretty good then.

Found it on eBay for same price but free shipping, https://www.ebay.co.uk/itm/302084901600

As for media. I have some button holes that are 12x12mm. Would be nice to be able to have it finish them and make them smooth to the touch.
What media should I be using and what size?

From what I have read, the plastic stuff is ideal for aluminum as it is not too abrasive compared to the stone which is better for harder metal like Steel.

[edit] I also have this thing, it comes out a bit steppy. Would like to be able to have this come to a nicer finish.

[m_c]

Just measured it, and the base is about 14" diameter, and overall is height is about 19.5".

I use plastic 20mm pyramids, as I use it for deburring and finishing smallish aluminium parts. A 5Kg bag of the pyramids fills it up to around the mid level of the bowl.
I normally throw in what parts I'm doing, and let it rumble away for an hour, which seems to be enough to flatten all the surfaces and knock the burrs off.

I do also have some ceramic prisms, but I've never had a reason to try them.


However, it may be worth considering bead blasting, as I think it gives a nicer finish on flat surfaces, provided you get the technique good. It does however take more time, and you need good extraction/filtering, as you really don't want to be breathing sand or glass dust.

[JOGARA]

Would going to 10mm be better for the small wholes within my design and the concave part?
As for bead blasting, I don't really have the room. That and I need something I can just turn on and get on with other things like anodizing.

[Zeeflyboy]

Given they are fairly small parts with tight nooks and crannies I'm not convinced you'll be happy with anything other than sand blasting.

You could try tumbling in a finer abrasive material like aluminium oxide grit (Like often used for blasting), that's more likely to get into the internal corners etc than the large tumbling media. You might need to experiment a bit.

[JOGARA]

Dam this thing is gigantic.
And for £150 shipped that is quite impressive. I just hope it lasts long enough though.

Been talking with Moleroda Finishing and they are suggesting 10-20mm media.
10mm being higher chance of getting into the button holes I have so went for that.
Should arrive tomorrow and will get to tumble all day :)

Thanks for all the help guys.
Hopefully will come back with good results.