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View Full Version : Results from my home-built parts tumbler...



Wal
26-05-2014, 03:20 PM
Tumbled my first part yesterday - 6082 aluminium, no surface preparation - just as it came from the stock-holder.


https://www.youtube.com/watch?v=MhD7K4TUEYs

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Yes, the shinier part is the one that got tumbled... I used 3mm porcelain beads as the finishing media.

It took 10 hours to get the results you see - admittedly my tumbler is a tad underpowered:

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...and could benefit from spinning at 25-30RPM as opposed to it's lowly 14RPM (as covered in another post) but all in all I'm quite pleased with the results. Another 10 hours and it'd be close to mirror, I reckon...

Wal.

Clive S
26-05-2014, 03:47 PM
Nice job Wal, where did you get the beads? .. Clive

Wal
26-05-2014, 03:59 PM
Cheers Clive.

Beads came off e-bay:

3mm Porcelain Media 3Kg Vibratory Rotary Tumbler / Polishing Finishing | eBay (http://www.ebay.co.uk/itm/3mm-Porcelain-Media-3Kg-Vibratory-Rotary-Tumbler-Polishing-Finishing-/141260313203)

Not cheap, but they do the trick - if you're going to buy some give me a shout - I want to get some plastic media for de-burring, maybe we can combine p&p..?

Wal.

JAZZCNC
26-05-2014, 08:07 PM
Nice job Wal but a better finish than that would take me about 30mins on my bench polisher.? Can see the point of a tumbler for small parts and lots of them but not single larger parts like those.? What will be the main use.?

Wal
26-05-2014, 11:06 PM
Hi Dean,

Yeah, I hear ya - this was more of a test than anything. I have some buffing wheels/mops which I'm still getting the hang of - there's definitely a knack to be acquired. I had a go at the G that I cut a while back, I didn't give it enough prep/wet-dry etc, and there are some awkward areas to get into, but not a bad result. With all its nooks, I reckon it would tumble to a nicer finish once prepped properly...

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I also think that 1050 would benefit from tumbling, it's so bloody soft that those switch plates I did were even picking up micro-scratches from the Vienna lime/final polishing cloth...:grumpy: But like I say, might just be me not doing it right or a particularly soft batch of alu.

Anyway, with all that said - because most of what I do are 'one-off small scale no rush' jobs, I'm quite happy to pop parts like the plates in overnight - until I get the hang of polishing/buffing it's a good way to guarantee a consistent finish. With the quadrilateral plates in the OP it was also hugely important that the edges stayed as flat as possible - not something you'd want to ride a sisal wheel over...

Cheers!

Wal.

JAZZCNC
26-05-2014, 11:26 PM
Hi Dean,

Yeah, I hear ya - this was more of a test than anything. I have some buffing wheels/mops which I'm still getting the hang of - there's definitely a knack to be acquired.

Oh yeah tell me about it I've spat a few parts across room before and wrecked few also. Agree for parts like that G then tumbler would be miles easier and give better finish. Some time ago I made some 50 or so tiny decorative brass handles for handbags and each one needed polishing to a high shine and this took twice longer than making the bloody things.!!

Wal
26-05-2014, 11:44 PM
Heh, yep - polishing's definitely approaching an art-form. I'm using my wheels on a slow pillar drill/hand-drill, takes some coordination to keep the workpiece moving whilst remembering to keep its edges out of the way of the on-coming wheel!

Nothing worse than thinking you've ruined a bit of work by polishing in a groove... Well, except maybe when the wheel grabs it off ya and chucks it on the floor.

Wal.

longy
27-05-2014, 03:32 PM
Wal, have you got anything inside the tub to help agitate the beads ? Or are you just relying on rotational gravity to move the beads and materials. You would get a quicker turnaround by making the beads and material move around more inside the tub other than just sliding. Think along the lines of a tumble dryer and add some baffles inside the tub.

Wal
29-05-2014, 01:23 AM
Hi Longy,

Yeah, I have a couple of strips of wood that help flip the part and increase the internal chaos...

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Not that there's much internal chaos going on at the mo - the weedy motor finally released it's magic smoke and ceased to turn forever more...

So the search continues for a small quiet motor that likes to run continuously and is strong enough to turn the barrel. I've found replacement Thumler motors available in the States for around $25-30, double that once p&p+duty get charged on top. Quite honestly I'm thinking to myself - just buy one of these:

3lb Barrelling Machine | UKGE (http://www.ukge.com/en-gb/Lapidary/Metal-Barrelling/3lb-Barrelling-Machine__p-14-253-1162.aspx)

So much for DIY - totally does my nut in that I'm unable to buy (easily and on these shores) a small AC or DC motor up to the job at a reasonable price..!

Bah!

Wal.

longy
29-05-2014, 03:34 AM
Wal, are you still on 12V ? try a breaker yard for second hand wiper motor they will go all day and you get the gearbox to play with. Not sure on the rpm but I would think that wiper motors will have a fare bit of torque. Hope these help http://www.ebay.co.uk/sch/i.html?_trksid=p2047675.m570.l1311.R4.TR12.TRC2.A0 .H0&_nkw=tumbler+polisher&_sacat=0&_from=R40

or http://www.ebay.co.uk/itm/Tumble-Master-Stone-Polisher-2-Drums-Grit-Cerium-Oxide-Spare-Belt-User-Guide-/181415801175?pt=UK_Collectables_RocksFossils_Miner als_EH&hash=item2a3d397157

Iwant1
29-05-2014, 10:28 AM
Wal, I've used a microwave motor in the past for a project. they operate on 240v though and are quiet and about 2 quid. Here's one on ebay with 33RPM speed.

AC 220-240V 4W 33RPM CW/CCW Microwave Oven Synchronous Motor | eBay (http://www.ebay.co.uk/itm/AC-220-240V-4W-33RPM-CW-CCW-Microwave-Oven-Synchronous-Motor-/290940082864?pt=UK_BOI_Electrical_Components_Suppl ies_ET&hash=item43bd615ab0)

Wal
29-05-2014, 12:42 PM
Wal, I've used a microwave motor in the past for a project. they operate on 240v though and are quiet and about 2 quid. Here's one on ebay with 33RPM speed.

AC 220-240V 4W 33RPM CW/CCW Microwave Oven Synchronous Motor | eBay (http://www.ebay.co.uk/itm/AC-220-240V-4W-33RPM-CW-CCW-Microwave-Oven-Synchronous-Motor-/290940082864?pt=UK_BOI_Electrical_Components_Suppl ies_ET&hash=item43bd615ab0)

Cool, I may jib down to the local tip for a rummage... Thanks for the heads-up! You too, Longy - wiper motor certainly looks feasible.

Wal.

Clive S
29-05-2014, 02:08 PM
Cool, I may jib down to the local tip for a rummage... Thanks for the heads-up! You too, Longy - wiper motor certainly looks feasible.

Wal. Wal how about a small stepper motor. ..Clive

Wal
29-05-2014, 02:18 PM
I did think about that, Clive (you might have suggested it in passing a while back) - was worried that they get pretty hot under continuous use, if I ran it off my control box under a new LinuxCNC profile, it would mean leaving my gear powered up unattended, not too keen on that either - call me paranoid..!

Something will turn up!

Wal.

Jonathan
29-05-2014, 03:20 PM
A microwave motor may work well. If you spin one round and poke your fingers on the terminals you get a reasonable shock, which is quite entertaining.

A cheap (i.e. 2nd hand) drill should also work without requiring much gearing.


Wal how about a small stepper motor. ..Clive

Stepper motor are good (ish) when you need to control position, but for spinning things in general you're better off with other motor types as they're a lot more efficient and simpler to drive, so should be cheaper.

gavztheouch
29-05-2014, 03:26 PM
Why not weld a container to the centre of your car wheel and go for a drive. Better still do it on the morning commute.

Wal
29-05-2014, 04:19 PM
Gav,

You're not taking this seriously, are you..?

Wal
07-07-2014, 03:29 PM
Sledgehammer -

Meet walnut...


http://youtu.be/4dPheoMLq6Q

230VAC cap-start induction motor.

Having contacted several places in the UK - and had literally zero replies - the motor (5IK40GN-C) was eventually bought from China (Ningbo Leison Motor Co.) along with a couple of gearboxes (30rpm/60rpm). Great service, gearboxes made to order with no problems or delays whatsoever!

Since buying, I've come across this company:

http://www.vipa.co.uk/products/vipa-drives/ac-induction/

Who offer very similar motors at prices (once duty and p&p are taken in to account) that are near comparable with what you'd pay buying in from China. Furthermore, the guy in sales knew what he was talking about and responded within minutes.

Anyway, if this project has taught me anything, it's this: "A good electric motor that you want to perform a specific task is going to cost you a bit more than you thought."

Which could well be a Chinese proverb...

Wal.