CNC advice please? Can anyone look at this spec and advise me?

[Kevin Mahoney]

I’d be keen to know more from experienced cnc users on here as well, may be buying one in the new year if a few rogue punters pay their bills. What kind of thing are you doing with it Patrick?

[Stephen Morriss]

If it’s well made and assembled then it should be Ok, but I’d be wanting to see it in operation for that price.
Can they put you in touch with someone who already has one?

You also need some extra info.
Spindle speed range and tool sizes (collet type)?
Axis feed rates?
How is the gantry moved, belt or leadscrew? The Y axis looks to be a leadscrew.
What backlash is present if leadscrews?
What material are the leadscrews and nuts?

There’s nothing wrong with leadscrews as long as they don’t have a lot of backlash and also have a method of adjustment, good quality ballscrews are good as they have very little backlash and are usually hardened.

The spindle speed and feed rates have a huge impact on how fast you can cut and the type of tooling you can use, if the feed rate is too slow then you have to use single flute cutters because you need a minimum cut per tooth or you just wear the tool from rubbing. So if the tool is spinning at 7000 rpm and the max usable feedrate is 500mm/min that’s 500/7000 = 0.071mm cut per revolution for a single flute cutter, half that for a 2 flute etc.
Look on a few tooling sites and look for recommended chip load for various materials you think you’ll be cutting.

I know my home built router struggles to run fast enough for the rpm of the spindle so I can end up burning cutters and causing excessive wear.

Steve

[NeilRoss]

quote Stephen Morriss:

The spindle speed and feed rates have a huge impact on how fast you can cut and the type of tooling you can use, if the feed rate is too slow then you have to use single flute cutters because you need a minimum cut per tooth or you just wear the tool from rubbing. So if the tool is spinning at 7000 rpm and the max usable feedrate is 500mm/min that’s 500/7000 = 0.071mm cut per revolution for a single flute cutter, half that for a 2 flute etc.
Look on a few tooling sites and look for recommended chip load for various materials you think you’ll be cutting.

I know my home built router struggles to run fast enough for the rpm of the spindle so I can end up burning cutters and causing excessive wear.

Steve

Have you seen SuperPid, Steve? Total control of speed without loss of torque. I’ve been using it for years now and I wouldn’t be without it.
http://www.vhipe.com/product-private/SuperPID-Home.htm

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[Stephen Morriss]

That’s a good find, thanks.

Steve

[Patrick Donaghey]

quote Stephen Morriss:

That’s a good find, thanks.

Steve

Thanks Kevin and Stephen , I’m going to get a demo of it but it can cut aluminum , they do a cheaper version that can’t cut solid aluminium, it’s a local supplier in Ireland and it comes with a pc and software , I’ll post the website when I find it the guy is really helpful so far

[Stephen Morriss]

If the supplier/manufacturer is local and gives good support then that’s worth a lot, but get a current owners opinion too.

Most routers can cut Aluminium, it’s how well they do it that matters. I cut some parts with mine from 6mm 6000 series Ali using a 3mm single flute carbide bit and lots of passes, they came out usable but my CNC mill would have cut them in one pass and left a near polished edge, but while it’s much bigger than the router it’s cutting area is tiny in comparison to the router.

One use I’ve put my router to that I never thought of when I made is was cutting 1mm foamed PVC using a plotter blade in a special holder, I’ve made loads of paint masks for people using this, quite slow but they came out great. Vectric V Carve has an add on that you setup to create the files.

Steve

[Wayne Maxwell]

quote Patrick Donaghey:

Hi I’m looking at buying this machine would anyone be able to help With any advice about the spec of this machine it’s £3750

Patrick… Did you ever get this machine.. How’s it working for you.. Good or bad?