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DoESLiverpool / somebody-should

A place to document practices on the wiki and collect issues/suggestions/to-do items for the physical space at DoES Liverpool
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Pledge: rock tumbler for post-processing CNC machined items, and more. #1023

Open MatthewCroughan opened 5 years ago

MatthewCroughan commented 5 years ago

We need one of these tumbler appliances to process raw items that come off the cnc, here's a look at what Julian has done with his swan-neck parts.

The part on the right is unprocessed, straight from the CNC machine. And on the left is the gorgeous tumbled part which is just beautiful, this can be applied to almost anything hard that is cut on the CNC machine. They're often used to make nice, shiny, smooth stones.

img_20190105_182710

I've no idea what would constitute a superior tumbler. But these seem to be a good place to start, since it's not rocket science. You simply rotate a cylinder in a filled tube of blunt stones that continually smash into the items you place in the appliance, smoothing its corners. Like a slow cooker for metal parts!

Here's a before and after of random stones, perhaps found on the beach; image

It would seem that this comes with a US plug according to some reviews, which shouldn't be a problem. One pre-requisite is that it has a rubber interior, to prevent it from being incredibly noisy, bashing against plastic etc.

https://www.amazon.co.uk/NATIONAL-GEOGRAPHIC-Hobby-Rock-Tumbler-x/dp/B01LQCIL88/ref=sr_1_3?ie=UTF8&qid=1546746600&sr=8-3&keywords=rock+tumbler

To avoid getting ripped off, we should take a look at alternatives and make an educated decision, such as:

https://www.ukge.com/en-gb/Stone-Tumblers/2lb-Beach-Stone-Tumbler__p-252-1188.aspx

Pledge status:

johnmckerrell commented 5 years ago

Sounds like a good candidate for a pledge drive, if you can arrange it within 4 hours!

-- Sent from my mobile phone hence brevity and errors

On 6 Jan 2019, at 04:03, MatthewCroughan notifications@github.com wrote:

We need one of these tumbler appliances to process raw items that come off the cnc, here's a look at what Julian has done with his swan-neck parts. The part on the right is unprocessed, straight from the CNC machine. And on the left is the gorgeous tumbled part which is just beautiful, this can be applied to almost anything hard that is cut on the CNC machine. They're often used to make nice, shiny, smooth stones.

I've no idea what would constitute a superior tumbler. But these seem to be a good place to start, since it's not rocket science. You simply rotate a cylinder in a filled tube of blunt stones that continually smash into the items you place in the appliance, smoothing its corners. Like a slow cooker for metal parts!

Here's a before and after of random stones, perhaps found on the beach;

It would seem that this comes with a US plug according to some reviews, which shouldn't be a problem. One pre-requisite is that it has a rubber interior, to prevent it from being incredibly noisy, bashing against plastic etc.

https://www.amazon.co.uk/NATIONAL-GEOGRAPHIC-Hobby-Rock-Tumbler-x/dp/B01LQCIL88/ref=sr_1_3?ie=UTF8&qid=1546746600&sr=8-3&keywords=rock+tumbler

To avoid getting scammed just for the "national geographic" brand name, we should take a look at alternatives and make an educated decision, such as:

https://www.ukge.com/en-gb/Stone-Tumblers/2lb-Beach-Stone-Tumbler__p-252-1188.aspx

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Sean-anotherone commented 5 years ago

Or build one - I've seen a jewellery-sized one made from an old go-kart tyre.

goatchurchprime commented 5 years ago

Let's start with that cheap one, to get it right and get it in use. Any votes for this yet?

Thingomy commented 5 years ago

Just to mention, I understand that these things are prohibitively noisey, and (for processing rock at least) very slow. Think spending a chunk of a week listening to some marakas in a washing machine. If located off site somewhere, it could work, but unless only being run for a few hours over night, I can't see it working in the space.

MatthewCroughan commented 5 years ago

@Thingomy I thought that a thick, rubber/foam external housing would mitigate the noise. Is it really so noisy that we could not make a housing around it out of laser cut wood and sound absorbent foam?

MatthewCroughan commented 5 years ago

Is anybody interested in pledging towards the national geographic one I've linked from Amazon? I'm going to pin this issue now to experiment with how we can attract more attention for pledges.

JackiePease commented 5 years ago

I'll pledge £10

MatthewCroughan commented 5 years ago

I'll pledge £20

DoESsean commented 5 years ago

I've shared this issue to the Google Group to see if there's any interest.

ajlennon commented 5 years ago

I'll pledge £10

ajlennon commented 5 years ago

3KG here for £50. 5KG for £80

https://www.amazon.co.uk/gp/product/B07D7NSXZT?pf_rd_p=330fbd82-d4fe-42e5-9c16-d4b886747c64&pf_rd_r=C32JS85HPHCDV75F5FXY

MatthewCroughan commented 5 years ago

@ajlennon I've been told to beware ones like that since they produce a ridiculously loud noise, since they're lacking any sort of rubber/dampening. Not that we couldn't make our own dampening. Imagine the sound of hailstone on the top of a shanty house :)

chris-does commented 5 years ago

I am happy to contribute "the rest" of the necessary funds, if the following approach is acceptable:

Looking at the Amazon price history for the National Geographic Hobby Rock Tumbler Kit it would seem that whilst the RRP for the item is £74.99 and the current price is £69.99, the item has frequently been available for around £50 over the last twelve months:

1023 - Rock Tumbler Pledge

Assuming the need for the tumbler is exploratory in nature and not urgent, it may be prudent to hold off on an immediate purchase and instead wait to buy until the price is again around the optimum of c£50 (acknowledging that waiting indefinitely is not desirable either, so if the price reaches within - say - 10% of the optimum, then proceed with the purchase at that point).

If my arithmetic is correct, that would mean the current funding is as follows:

@jackie1050 = £10 @MatthewCroughan = £20 @ajlennon = £10

already pledged = £40

@chris-does contribution of "the rest" = maximum optimum purchase price (£50 +10% = £55) - already pledged (£40) = £15

Total (maximum) available funds = £55

For this approach to work, the price for the National Geographic Hobby Rock Tumbler Kit would need to be tracked and then the purchase made as soon as the above criteria are met.

If this approach is acceptable; I am happy to undertake the ongoing price track and make the purchase as soon as the above criteria are met.

DoESsean commented 5 years ago

It looks like no-one picked up on this, but that seems like a good idea to me @chris-does.

Any objections @MatthewCroughan?

MatthewCroughan commented 5 years ago

@DoESsean No objections, it doesn't look like we've found a cheaper rubberised alternative to this seemingly overpriced nat-geo one, I'm happy to continue with my pledge.

@chris-does That's excellent, what is the price tracker you used? That looks useful for many things I've wanted to research in the past.

chris-does commented 5 years ago

My apologies for the delay in posting this reply - I have been tracking the item (which I continue to do) as soon as I saw the above posts on 5th September; I haven't hit the "Buy-It-Now" button yet, but my finger hovers ready . . .

@MatthewCroughan I am glad you like the tracker, I use the two listed below most (amongst others) and the image above is taken from the first:

  1. Keepa
  2. camelcamelcamel

I should say - I use separate service specific accounts with both providers and never actually purchase anything from within the same browser session as that in which I have the plugins / sites running - I'm quite happy for each service to build a picture of all the things that those accounts track, I'm less happy for them to know precisely which items an account personally identifiable as me purchases :-) I have never had any negative experiences with either provider, or any issues related to data breach either, though as ever with such "free" services caveat emptor and YMMV :-).

chris-does commented 4 years ago

The National Geographic Hobby Rock Tumbler Kit is currently in stock and priced at £59.99.

This is £10 less than when I first posted above, and is now only £4.99 more than my suggested "maximum optimum purchase price".

If somebody did want to contribute the extra £4.99 I am happy to go ahead and make the purchase.

However, I am hoping that with the "Black Friday" sales period rapidly approaching that the price will go below £55 - and ideally even under £50 - there is certainly evidence of this occurring in the past around "Black Friday", "Prime Day" and other "Lightning Deals".

DoESsean commented 4 years ago

Great idea about the sales, I would imagine it's definitely worth holding on given that it's only a few more days.

On Tue, Nov 19, 2019 at 11:15 PM chris-does notifications@github.com wrote:

The National Geographic Hobby Rock Tumbler Kit https://www.amazon.co.uk/NATIONAL-GEOGRAPHIC-Hobby-Rock-Tumbler-x/dp/B01LQCIL88/ref=sr_1_3?ie=UTF8&qid=1546746600&sr=8-3&keywords=rock+tumbler is currently in stock and priced at £59.99.

This is £10 less than when I first posted above, and is now only £4.99 more than my suggested "maximum optimum purchase price".

If somebody did want to contribute the extra £4.99 I am happy to go ahead and make the purchase.

However, I am hoping that with the "Black Friday" sales period rapidly approaching that the price will go below £55 - and ideally even under £50 - there is certainly evidence of this occurring in the past around "Black Friday", "Prime Day" and other "Lightning Deals".

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chris-does commented 4 years ago

Quick update, the slightly larger version (they call it "professional", but I am not entirely sure about that moniker) received a decent level of discount (33%) during the past few days.

This is cheapest this model has ever been sold for, and so I thought it was worth the extra cost to have a slightly larger capacity tumbler - increasing the scope of the items we can try tumbling before investing in something considerably more substantial / building our own. . .

Therefore I have ordered National Geographic Professional Rock Tumbler Kit

This should be delivered directly to DoES on (or before) Thursday 5th December 2019.

I am not sure if there is a specific way that pledges need to be accounted for within DoES (as opposed to other types of purchase / funding endeavour), but if not I assume we

just provide our pledges to @DoESsean.

DoESsean commented 4 years ago

Bought, placed in the CNC room.

I assume @chris-does needs reimbursing? Which means we'll need @MatthewCroughan, @jackie1050 and @ajlennon to hand in their pledges (unless they've already done so, of course).