Jewelry polisher machine - Alternative to block sander

[modeller_masa]

 

 

Hello.

Have you heard about a jewelly polisher or bead polishing machine? When I saw the above article about a blockbuster, I quickly reminded this machine.

 

I purchased it from Aliexpress at $64 includes shipping fee to South Korea, and it works really well.

 

You may know better way to make deadeyes. I hope my experience helps you if you wanted this kind of machine.

[Thistle17]

This looks like a well made machine with good features however it is a bit more on Amazon.

Joe

[Bob Cleek]

I'd like to hear some more evaluations of its performance. My concern is that wooden blocks and deadeyes lack the weight to be sanded evenly in the polishing media used in such polishers. The block sanders which employ sandpaper "paddles" whack the blocks and keep them moving so they evenly contact the sandpaper paddles and sides of the container. With revolving drum rock polishers and "brass polishers" (used by reloaders for polishing firearm cartridges) the weight of the items polished contributes to the polishing as the container is rotated. It's the items' falling in the abrasive media as the container rotates that polishes them. With tiny wooden blocks, they just rotate along with everything else and don't really "rub" against the abrasive media. It's about the weight of the items being polished. Little wooden parts just aren't heavy enough for the mechanics of the thing. At least that's been my experience trying it with a brass polishing machine.

 

Has anybody else had the same experience?

[Gregory]

I tried one of those rock tumblers on the typical kit blocks, and it took over a week of tumbling just to knock the edges off.

Still had to do some work to define the sheaves, and of course it was no help at all when the sheave holes were near the center like you find on so many of them.

 

Syren came along, and i never looked back,,

[modeller_masa]

4 hours ago, Gregory said:

I tried one of those rock tumblers on the typical kit blocks, and it took over a week of tumbling just to knock the edges off.

Still had to do some work to define the sheaves, and of course it was no help at all when the sheave holes were near the center like you find on so many of them.

 

Syren came along, and i never looked back,,

I figure out it is called a 'rock tumblers' in the western.

 

You may be right. I tested an inch cubic block of hinoki cypress, which is considered a softwood. The condition I tested was here.

- The fastest speed at 5

- An inch cubic hinoki cypress

- An hour

- 180 sandpaper

 

It can take lots of time like you said when I use a hardwood. The structure of it is little bit different from the block sander. (less contact surface)

 

I'll update a result using walnut block soon. (May be next week)

Edited February 22, 2020 by modeller_masa

[modeller_masa]

These blocks are from HMS Bounty kit by Mantua Sergal in 1973. I honestly say that this machine may not be able to handle the center deadeyes, so I'll test both of blocks only. I think the blocks are walnut. The kit used lime, walnut, and birch plywood only. Here are dimensions. 

 

- Left : 3.5 x 3.5 x 5.5 mm
- Right : 3.2 x 3.2 x 4.8 mm

 

To show a quick result, I'll make walnut pieces rather than a full block. I'll show you flatness and scratches on the block as much as possible.

[Gregory]

My point about sheave holes.

 

You could finish them until the shape looks like Chuck's blocks, but the sheave hole in the middle blows the whole deal.

[modeller_masa]

You're right. I've already given up to make blocks with this machine only while I'm testing.

 

The better process should be using microshapers by AL or etc.

 

(1) Shaping both side of the strip with AL microshapers

(2) Making the sheaving holes.

(3) Cutting the strip.

(4) Polishing the block using this machine for an hour.

 

I'll post the final result within a few days, but my current conclusion is that the rock tumbler is a 'polishing machine' as it was designed. It can't shape the block, but It can make the surface smooth without sanding by hand. It would be useful to polish blocks from kit which is considered rough condition frequently.

Edited February 22, 2020 by modeller_masa

[AON]

I had the idea weeks ago to make a sand tumbler.  I saved a Orville Redenbacher Popcorn plastic bottle and screw top, and drilled a hole in the base for a bolt.  I slipped a flat washer and O-ring over the bolt to seal it to the bottle base to keep the sand in.

 

I intend to get a small bucket of clean beach sand to use in the "tumbler", but haven't made it out to the shore of Lake Erie just yet (a 30 minute drive).  I'd fill the container about quarter full to start and slip the bolt into my wood lathe set to it's slowest speed.  Toss in some scrap bits with holes drilled through for a test run.  To empty it I'd dump the contents back into the bucket with a screen/sieve to catch the parts.

 

I got the idea from fluidized bed furnaces and hopper screw augers used to remove debinded casting sand from Solution Furnaces.  The former had sand flow like a fluid through every crack and crevice to heat treat gears, bolts, golf clubs, etc.. The latter seemed to be self cleaning via sand rubbing against the hopper and chute.  So I imagine the sharp edges of the tiny sand grains would wear away and soften the edges of blocks, grooves and holes.

 

All I need now is the darned sand.

[Jaager]

On 2/21/2020 at 4:09 PM, Bob Cleek said:

The block sanders which employ sandpaper "paddles" whack the blocks and keep them moving so they evenly contact the sandpaper paddles and sides of the container.

T bought a Harbor Freight one drum tumbler some time ago.  With the $20 off coupon it was economical.  Still in its box and stored on a shelf.  I have it in mind to find a way to add a dowel thru the central axis and that does not turn and has four flaps of sand paper.  It would be fixed flappers and moving perimeter,  My usual armchair experiment mode has me wondering just vertical or near vertical flappers should be the thing.  The end sections would need trauma to fit the dowel.  I wonder if something like an empty can of Dole's not from concentrate Pineapple juice would fit as a drum?  (The from concentrate stuff is vile.) 

[modeller_masa]

Sorry about not updating this article. I gave up to use this tumbler machine because of no benefit.

 

 

I shifted to much viable and convenient way than this one. I leave this article as a case of failure. I'll be appreciate if someone finds another use of this kind of machine. 👍

[Keithbrad80]

As a geologist i have access to a few rock tumblers, some of them are massive. The medium is really what does the rounding as the rock moves around in the tumbler. The important thing here is that your medium needs to be harder than the material you are cutting, the harder the material the rougher the cut. For instance quartz is a hard mineral that makes up most sand in the world, using quartz will provide a quicker and rougher cut than something like aluminum oxide which will provide a polish of sorts on your rocks (or wood). 

 

A rock tumbler is meant to reproduce the natural process of erosion, by knocking the wood or rock against the medium over and over and over. Because of this it takes a long time to see nice results. As I have never put wood in a rock tumbler I cant tell you what the effects might be but If you wanted to shape and rough up wood for blocks and dead eyes I would recommend a rough medium (silicon carbide) to cut away material for a few weeks, followed by a finer medium (aluminum oxide) to provide a pre polish of the wood. The down side of a tumbler is the only shape they can produce is spherical. what ever you leave in there will eventually become a sphere. Last point, remember to change your medium often, maybe once or twice a week but i would check your tumbler everyday to make sure nothing is coming loose. 

 

In terms of model ship building there are probably much easier ways to make blocks and dead eyes than a rock tumbler, though it is a nice idea!

 

Bradley 

[modeller_masa]

Thanks for professional advice, Bradley. I expected that it will be sphere eventually, but didn't test it for that long time. Even I didn't know how to use this tumbler properly. Also, your interesting explanation gives me some idea. It may be too early to throw away this machine...

[reklein]

Looks like a great idea. I like the way you tested the idea Masa. Consider driftwood on a sandy beach all nice and smoth and rounded. If you try sand I would recommend a nice sharp sand rather that beach sand. Sand from a crusher perhaps. Some aquarium sands may be suitable.  Bill in Idaho