3-Axis precision mini CNC machine

[xzswq21]

Quote from: sokoloff on Today at 12:53:20 pm

    If you want to build your own machine, I think the first step is to become familiar with a commercial machine (ideally a low-end and a mid-grade machine separately), spend a couple hundred hours making parts and chips, and see what they did and why.


and a CNC is great help when building a CNC

At the very least, access to a machine shop with decent quality manual machines (and the knowledge and experience to use them).  If you don't know what you're doing, the only recourse is to pay somebody for their expertise and buy a machine or kit that meets your requirements.

One alternative is to get a cast iron bench mill drill (Chinese clones are all over the market) and then a refit CNC kit..  These things are > 1-300Kg, so not really that big as far as machines go.  Find the refit kit first before you get the mill though.

The only constant here is that it's going to cost a fair amount of money.  Precision and machining steel/stainless does not come cheap.

What do you think about this machine?
https://forsuncnc.com/mini-cnc-router-fs4040a/

They claimed "Cast steel table structure and side support, Aluminum gantry, aluminum T-Plate Extrusion Combined table" and "All the spare parts are a world-famous brand like Siemens controller from Germany, Yaskawa servo motors from Japan, Igus cable from Germany, ABB from Switzerland, and so on"..

But it's a Chinese company and I'm scared to rely on their specifications.

[PaulAm]

Looks fine for wood or plastic.

[Benta]

Looks fine for wood or plastic.

Yep. Quote from the description:
"Mainly used in the engraving, punching, and cutting of PVC, acrylic, two-color board, engineering plastics, etc."

Says it all.

[Benta]

We should be a bit careful with metal-working machine terminology here:
A fixed flat-bed machine with moving gantry is a router.
A fixed-head machine with moving X-Y table is a mill.

Routers are mainly for engraving and contour cutting in soft materials. The whole construction principle does not allow for the rigidity needed for working in steel (unless you make it extremely massive).

A mill is a different story, and can basically be built to very high rigidity with little effort.

A very popular CNC mill setup in the hobby/prototyping scene is the Sieg SX2 with added CNC kit. The machine is from Shanghai, but good quality.
http://www.siegind.com/product_detail/sx2-mini-mill-drill-15008858857815262.html
The X2 is rigid enough for steel and SS using reasonably sized cutters (from experience: up to ø4 mm, with care ø6 mm).

Ready to bolt on CNC kits are available from several supplies, eg, Heavy Metal CNC or CNC Conversion Plus.

Downside to the Sieg SX2: the X/Y working envelope is just 100 mm x 220 mm.

But this is about as cost-effective as you will get.

[xzswq21]

We should be a bit careful with metal-working machine terminology here:
A fixed flat-bed machine with moving gantry is a router.
A fixed-head machine with moving X-Y table is a mill.

Routers are mainly for engraving and contour cutting in soft materials. The whole construction principle does not allow for the rigidity needed for working in steel (unless you make it extremely massive).

A mill is a different story, and can basically be built to very high rigidity with little effort.

A very popular CNC mill setup in the hobby/prototyping scene is the Sieg SX2 with added CNC kit. The machine is from Shanghai, but good quality.
http://www.siegind.com/product_detail/sx2-mini-mill-drill-15008858857815262.html
The X2 is rigid enough for steel and SS using reasonably sized cutters (from experience: up to ø4 mm, with care ø6 mm).

Ready to bolt on CNC kits are available from several supplies, eg, Heavy Metal CNC or CNC Conversion Plus.

Downside to the Sieg SX2: the X/Y working envelope is just 100 mm x 220 mm.

But this is about as cost-effective as you will get.

Thanks
Do you know a precision lathe machine? I want to buy a Proxxon PD 250/E, it's 1600$ with the accessories.

[Benta]

Thanks
Do you know a precision lathe machine? I want to buy a Proxxon PD 250/E, it's 1600$ with the accessories.

Don't, you'll regret it. I know the PD250 well, and it's flimsy, has no features and is overpriced.

The minimum I'd go for is something like this:
https://www.stuermer-machines.com/brands/optimum/category/product/optimum-lathes-conventional/optiturn-tu-2004v-3420310/
But I'd recommend going up one size:
https://www.stuermer-machines.com/brands/optimum/category/product/optimum-lathes-conventional/optiturn-tu-2304-3420320/

MT3 headstock, MT2 tailstock, proper carriage movement etc.

Accessories? Pfft! The only thing you need to start with is cutters. Order those when you have a machine to be certain of the correct shaft size. They're not expensive, you can get a set of 5 different modular carbide cutters for 100 Euro (but you'll probably only need two of them).
After that you can start considering drill chuck and live center for the tailstock and center drills. Also not really expensive.


The links are not because I endorse the machines or have any affiliation, but to show the kind of machine I recommend. You can probably find almost identical machines at 2/3 the price as China non-brands.