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jmac80
24-11-2013, 09:37 AM
Hello everyone

This is my first post here so please be gentle ;)
What I would like to do is cut small shapes from metal plates, mostly aluminium but at lower grades like 1050 and about 16gauge / 1.4mm thick as it would be used for jewellery.
It would be small designs and shapes, circles stars etc on average about 1" diameter.
Now I thought I found the perfect machine with a cheap Chinese cnc router but after a fair bit of reading it would seem that it's not the best machine for the job on softer metals.
Is there a machine out there that would be suitable for this? Have a budget of about 2-3000.

Thanks very much

GEOFFREY
24-11-2013, 11:23 AM
Hello and wellcome to the site. I think that you will find that a small, but rigid cnc mill will be better than a router and there will certainly be some used (already converted) machines available within your budget. good luck with your search. G.

jmac80
24-11-2013, 11:28 AM
Hello and wellcome to the site. I think that you will find that a small, but rigid cnc mill will be better than a router and there will certainly be some used (already converted) machines available within your budget. good luck with your search. G.

Thanks for the welcome Geoffrey

Could you post me a link to the kind of machine your talking about please.

Jonathan
24-11-2013, 11:30 AM
What I would like to do is cut small shapes from metal plates, mostly aluminium but at lower grades like 1050

If you can choose the grade then don't choose 1050, as it's difficult to cut. You'd be better off with 6082 for instance.


and about 16gauge / 1.4mm thick as it would be used for jewellery.
It would be small designs and shapes, circles stars etc on average about 1" diameter.
Now I thought I found the perfect machine with a cheap Chinese cnc router

To get the 'perfect machine' for that budget, you'd need to make your own. A CNC mill would be acceptable, but it would be much better if a high speed spindle was added as you'll be using very small cutters.

The Chinese CNC routers you see on eBay are fine for the engraving, but they would take a long time to cut out the part. If you're making lots of these then you want a better machine. If it's just a few here and there then go for it...

jmac80
24-11-2013, 11:46 AM
Thanks
so how on earth do people cut stuff like this from thin 1000 series aluminium

Aluminum Metal Blanks 20 Gauge Hearts for Hand Stamped Jewelry 20mm | eBay (http://www.ebay.com/itm/Aluminum-Metal-Blanks-20-Gauge-Hearts-for-Hand-Stamped-Jewelry-20mm-/160996392577)

5 Metal Stamping Blanks 20 Gauge Aluminum Washers for Hand Stamped Jewelry 3 4" | eBay (http://www.ebay.com/itm/5-Metal-Stamping-Blanks-20-Gauge-Aluminum-Washers-for-Hand-Stamped-Jewelry-3-4-/161155794708)

Aluminum Metal Blanks 20 Gauge 1 2" Blanks for Hand Stamped Jewelry | eBay (http://www.ebay.com/itm/Aluminum-Metal-Blanks-20-Gauge-1-2-blanks-for-Hand-Stamped-Jewelry-/161019994997)

magicniner
24-11-2013, 11:55 AM
Thanks
so how on earth do people cut stuff like this from thin 1000 series aluminium

Aluminum Metal Blanks 20 Gauge Hearts for Hand Stamped Jewelry 20mm | eBay (http://www.ebay.com/itm/Aluminum-Metal-Blanks-20-Gauge-Hearts-for-Hand-Stamped-Jewelry-20mm-/160996392577)

5 Metal Stamping Blanks 20 Gauge Aluminum Washers for Hand Stamped Jewelry 3 4" | eBay (http://www.ebay.com/itm/5-Metal-Stamping-Blanks-20-Gauge-Aluminum-Washers-for-Hand-Stamped-Jewelry-3-4-/161155794708)

Aluminum Metal Blanks 20 Gauge 1 2" Blanks for Hand Stamped Jewelry | eBay (http://www.ebay.com/itm/Aluminum-Metal-Blanks-20-Gauge-1-2-blanks-for-Hand-Stamped-Jewelry-/161019994997)

If I had to produce large quantities of those I'd CNC press tooling for my Fly Press. It's a substantial initial investment in time, tool steel and heat treatment but the payoff is making a part in less than a second with a short pull on the press handle.
If you were really posh you could also have press tooling trim off the waste from the previous part, along with a back guide and an end stop the work would then be self-aligning in the press ;-)
Regards,
Nick

Jonathan
24-11-2013, 11:56 AM
Thanks
so how on earth do people cut stuff like this from thin 1000 series aluminium


They're stamped, like this:
Metal Stamping - YouTube (http://www.youtube.com/watch?v=bx_G3ALwvbA)

Can do it with a fly press if it's small...

jmac80
24-11-2013, 11:59 AM
So lol.............
Can i do it on a machine for under 2k?
the largest i would need to stamp is maybe 3" (if that)

EddyCurrent
24-11-2013, 12:34 PM
I think this is currently the cheapest on ebay that includes delivery, seeing as you are well North.
J Nielson No 2A Deep Throat Fly Press c/w 2 Weights | eBay (http://www.ebay.co.uk/itm/J-Nielson-No-2A-Deep-Throat-Fly-Press-c-w-2-Weights-/301022225097?pt=UK_BOI_Metalworking_Milling_Weldin g_Metalworking_Supplies_ET&hash=item461652a2c9)
Then you could use the spare 1.85k to get some tooling made

If you could stretch your budget there's this :highly_amused:

sheet metal punch presses-in Punching Machine from Industry & Business on Aliexpress.com (http://www.aliexpress.com/item/sheet-metal-punch-presses/372018534.html)

Edit: Axminster have some nice little mills that you could maybe convert to cnc
http://stores.ebay.co.uk/Axminster-Tool-Centre?_rdc=1

magicniner
24-11-2013, 12:44 PM
So lol.............
Can i do it on a machine for under 2k?
the largest i would need to stamp is maybe 3" (if that)

Yes,
But you'll have to shop around ;-)
I picked up a nice but slightly problematic ex-educational mill that had already been converted for Mach3 for 650.
Replacing the DC motor & drive with a 3phase motor and drive plus some limit switches brought it up to 900, add a license for Mach3 and 4-Axis Standard BobCad/Cam V25 and it runs over your budget by a few hundred, but for what you want to do I'm sure there's some free or very cheap 2/2.5D Cad/Cam that would leave you space in your budget for a nice fly press - my No.3 cost me 80 from a local engineering tool dealer - he had around 20 in stock and I waved pound notes under his nose ;-) .
ATB,
Nick

RoboCutter
25-11-2013, 11:21 AM
Something like this maybe: https://www.stepcraft-systems.com/

jmac80
25-11-2013, 12:41 PM
Something like this maybe: https://www.stepcraft-systems.com/

hi
that does look a nice build, looks a lot nicer than the cheap Chinese ones.
would it basically been a router not mean it would make a mess of 1050 grade aluminium ?

Jonathan
25-11-2013, 03:08 PM
Something like this maybe: https://www.stepcraft-systems.com/

Judging by the photos on this page (https://www.stepcraft-systems.com/cnc-3d-systeme/stepcraft-600), the machine uses simple brass rollers on a (possibly?) aluminium extrusion to guide the X-axis. Although it looks like the rigidity of that system is adequate for engraving, I'd be concerned about the longevity.

The German word for 'ballscrew' is 'kugelrollspindel', but they've instead used 'Rundgewindespindel's, which are leadscrews. This means the machine is likely to have higher backlash, especially once the leadscrew nuts have worn a bit. This is confirmed by the 'Wiederholungsgenauigkeit' (positioning repetability) being +-0.05mm. That's enough to show up on a detailed engraving.

Interestingly they have given some measure of stiffness. Although it says torsional, the units imply linear stiffness hence I think they are saying that the machine will deflect by between 0.1mm and 0.14mm if a force of 20N is applied, so the stiffness is between 143N/mm 200N/mm. Unimpressive, though might be adequate as your requirements are small. The thing to do would be to ask someone who'se got one of the cheap machines from eBay (e.g. CNC6040, CNC3020) to measure its stiffness, then we can make an objective comparison.

GEOFFREY
25-11-2013, 10:31 PM
Thanks for the welcome Geoffrey

Could you post me a link to the kind of machine your talking about please.

A forum member has just posted a Denford starmill for sale. This is the sort of thing I meant and the Denfords are very nice little rigid mills. This one has already been converted, so is probably worth a pm to the owner. G.

jmac80
25-11-2013, 10:32 PM
thanks :) will go for a look!

IanS1
26-11-2013, 12:19 AM
I think you'll find it's been sold.

jmac80
26-11-2013, 12:22 AM
Yep.... Sold now

jmac80
26-11-2013, 11:58 AM
wondering will it just be easier to get the mrs a scroll saw, something like a hegner se with variable speed. then she can cut custom shapes from soft 1050grade aluminium with that. i tried on the aluminium myself with a jigsaw and metal blade, it cut fine so a scroll saw with metal blade should be good.... all be it slow but maybe ok for custom one off stuff.
From what i can see on videos on the net a cnc router would make a mess of soft aluminium.

jmac80
26-11-2013, 01:24 PM
does anyone have a small chinese style router i could send a small bit of aluminium sheet to to see if it cuts a shape ok?
i just don't want to spend a heap of money on one if it doesn't work! :)

EddyCurrent
26-11-2013, 02:24 PM
What happened, did the Mrs have other ideas ? :glee:

jmac80
26-11-2013, 02:32 PM
lol
don't think she like the idea of been in the cold garage cutting out shapes with a scroll saw hehehe

magicniner
26-11-2013, 04:30 PM
does anyone have a small chinese style router i could send a small bit of aluminium sheet to to see if it cuts a shape ok?
i just don't want to spend a heap of money on one if it doesn't work! :)

It will to some extent depend on how it's cut.
If you use a single flute ally cutter with a bit of light lube and have Cam software that will generate paths that move around the shape whilst ramipng down into the material at a constant rate, you should get a fairly neat cut. This is because you can set the depth of cut so it doesn't overstretch the machine rigidity whilst getting your part out at the optimum speed without multiple tool retractions.
Personally I wouldn't miss out on the chance to buy a CNC mill, Cad/Cam software and fly press ;-)

- Nick

EddyCurrent
26-11-2013, 05:15 PM
With the scroll saw you could get sharp internal corners but will a mill/router they would only be as tight as the cutter diameter allows then you're into hand filing. (unless there's a method I don't know about)

magicniner
26-11-2013, 07:11 PM
With the scroll saw you could get sharp internal corners but will a mill/router they would only be as tight as the cutter diameter allows then you're into hand filing. (unless there's a method I don't know about)

I think you're right, if the volume is low enough then hand cutting is always cheaper than buying or making new equipment

jmac80
26-11-2013, 07:17 PM
I think you're right, if the volume is low enough then hand cutting is always cheaper than buying or making new equipment

yes but have you seen the price of a decent scroll saw? lol
hegner multicut se is about 900 heheh
I suppose i could take a chance on a cheap proxxon scroll saw at about 120... but you always hear "buy cheap, buy twice" :)

EddyCurrent
26-11-2013, 08:18 PM
2 Hegners on ebay now

hegner saw | eBay (http://www.ebay.co.uk/sch/i.html?_from=R40&_sacat=0&_nkw=hegner+saw&_sop=15)

JAZZCNC
26-11-2013, 08:39 PM
does anyone have a small chinese style router i could send a small bit of aluminium sheet to to see if it cuts a shape ok?
i just don't want to spend a heap of money on one if it doesn't work! :)

First let me say the Cheap-O Chinese machines with the better spindle will be strong enough.! . . BUT. . .Unfortunately there's even more to it than what you think.?
To cut this stuff with any kind of finish you'll need flood coolant or a very Good Mist system with compressed air.

Then you have the problem of Holding down very small parts and Thin material.? It's a night mare and Even Vacuum won't help unless used with special Jigs has the parts are so small.

If you are bent on CNC then I wouldn't recommend the Chinese machines anyway has they are poor quality and can be troublesome which if your not CNC savy you won't want to deal with.
Router Style machine will Cut what you want no problem and just has good has any mill can. But Like the Mill it will need the correct cutters and tool-paths along with Flood coolant/Mist and serious thought on best way to hold down.

My honest opinion is to Seriously look at using a Punch press if volume is needed or stay with the Scroll saw thinking.!

EddyCurrent
26-11-2013, 09:05 PM
Agree, the scroll saw sounds far better when it comes to small thin metal pieces. I have a Rexon scroll saw which is okay if I need very tight curves otherwise I'd use a bandsaw every time but you would need to make a better insert from wood around the blade with a smaller gap than the original.

For your job maybe one of these ?

Jet JWBS-9 Bench Top Bandsaw - Bandsaws - Sawing - Wood Working | Axminster.co.uk (http://www.axminster.co.uk/jet-jwbs-9-bench-top-bandsaw)
Proxxon MBS 240/E Micro-Bandsaw - Modelling Tools - Modelling - Crafts & Hobbies | Axminster.co.uk (http://www.axminster.co.uk/proxxon-mbs-240-e-micro-bandsaw)

magicniner
26-11-2013, 11:17 PM
I made 20 of these competition prize badges in 3mm brass -

http://i135.photobucket.com/albums/q158/magicniner/BadgeResized_zpsab81830a.jpg (http://s135.photobucket.com/user/magicniner/media/BadgeResized_zpsab81830a.jpg.html)

I cut them on a bandsaw but if I had to make any more I think I'd CNC the profile and just sort out the sharp corners on the saw,

- Nick

JAZZCNC
26-11-2013, 11:54 PM
I cut them on a bandsaw but if I had to make any more I think I'd CNC the profile and just sort out the sharp corners on the saw,

- Nick

Nice Job that Nick but cutting 3mm brass is Sooooo much nicer and easier than shitty 1.5mm 1020 Ali chewing gum. . Lol

magicniner
27-11-2013, 12:47 AM
Nice Job that Nick but cutting 3mm brass is Sooooo much nicer and easier than shitty 1.5mm 1020 Ali chewing gum. . Lol

This is something I CNC cut from shitty 3mm Ali chewing gum ;-)

http://i135.photobucket.com/albums/q158/magicniner/CarriageFrame_zps555864c9.jpg (http://s135.photobucket.com/user/magicniner/media/CarriageFrame_zps555864c9.jpg.html)

I used a 2 flute Aluminium specific cutter with air to clear the chips, run at the right speed it cuts lovely, run it a bit slow and it looks like you're ploughing the material rather than cutting it and leaves 'orrible rough edges

JAZZCNC
27-11-2013, 10:32 PM
This is something I CNC cut from shitty 3mm Ali chewing gum ;-)


I used a 2 flute Aluminium specific cutter with air to clear the chips, run at the right speed it cuts lovely, run it a bit slow and it looks like you're ploughing the material rather than cutting it and leaves 'orrible rough edges

Again Nice Job and wasn't saying it can't be cut has I've cut ton's of the Stuff and like you say cut correctly with right cutters using good chip clearing a nice finish can be had.!!. . . . But Again cutting Thin Ali less than 3mm like the OP wants with Small dimensions is a pain at the best of times for experienced CNC users but for someone who's never used one or got much machining experience then it's completely different world, One of pain and frustration. . Lol