Epoxy granite vertical mill build log

[Nick]

I like them, I would struggle to give you any real reason to get them though. There well priced, reasonably well built, a ton of settings and configuration options, I don't think I will use half the functionality they have. I got them running quite quickly in analog speed mode. Compared to steppers they sound quieter, you get encoder feedback, potentially better high speed performance, index for homing and integrated power supply.

Main issues have been tuning the servo without dedicated software and documentation, i'm still far off on this and i'm not really taxing the drives which is a bit concerning. I know Clive has been having problems with large >1mm following errors on high speeds with step/dir setup and there are reports of several people having some interference issues with using them in step/dir.

[Clive S]

Main issues have been tuning the servo without dedicated software and documentation, i'm still far off on this and i'm not really taxing the drives which is a bit concerning. I know Clive has been having problems with large >1mm following errors on high speeds with step/dir setup and there are reports of several people having some interference issues with using them in step/dir.

Nick you are correct but I am in discussion with Peter he tell me the ping times are too high 0.35. I am now looking into that the PC I am using might be crap.

But not given up yet.

[Chaz]

Nick you are correct but I am in discussion with Peter he tell me the ping times are too high 0.35. I am now looking into that the PC I am using might be crap.

But not given up yet.

0.35 milliseconds?

[Nick]

Update:

I'm up to 3m/min rapid speed on X and Y, it will go a lot faster but the stand shakes and rocks. Got index homing, f-error < 0.03mm reliably, still not quite tuned but its working ok. I've got no idea on feeds and speeds, I keep stalling the 24k rpm spindle with larger end mills or gumming up smaller end mills.

Got the counter weight system in place now, went a bit over the top with the chain and mounts:



Which has meant I've finally got the Z-axis servo installed.

I think the next step is an enclosure, i'm using some Dexter like shower curtains at the moment chips are still going everywhere.

I'll get some designs done and see what you guys think

[Chaz]

Update:

I'm up to 3m/min rapid speed on X and Y, it will go a lot faster but the stand shakes and rocks. Got index homing, f-error < 0.03mm reliably, still not quite tuned but its working ok. I've got no idea on feeds and speeds, I keep stalling the 24k rpm spindle with larger end mills or gumming up smaller end mills.

Got the counter weight system in place now, went a bit over the top with the chain and mounts:



Which has meant I've finally got the Z-axis servo installed.

I think the next step is an enclosure, i'm using some Dexter like shower curtains at the moment chips are still going everywhere.

I'll get some designs done and see what you guys think

Congrats. The Z belt looks loose from the pic - is it tight?

The 24K spindles dont have a lot of torque. What KW rating is it?


When you say 'larger' endmills - what size and what RPM are you running them at? You should run pretty much everything at 24K RPM. Below 12K RPM these spindle will stall, drilling becomes a challenge, so interpolation is the best option. Smaller End mills being gummed up is too little lubrication if doing Alu - a bit of WD40 and you should be sorted. On my 'old' 4KW Chinese VFD Id run it at 24K RPM all the time, just adjust the feed rate based on cutter diameter (up to 12mm) which is pretty much max unless you go for some interesting facemill / MT adaptor which Id be concerned about using on these type of spindles.

You can do a bit of tweaking in the VFDs but not a lot if you use the standard HY one. You can get better ones - but then you might want to consider a 380V spindle and use something like the Ecogogo VFD that does Vector and upconverts the voltage.

[JAZZCNC]

I've got no idea on feeds and speeds, I keep stalling the 24k rpm spindle with larger end mills or gumming up smaller end mills.

What material are you cutting and what grade.? These spindles don't like large endmills or large drills, Not enough torque at the speeds required.
I pretty much exclusively cut Aluminium with mine and 8mm 3 flute works best. They will happily cut between 10-16K and will also drill at these speeds with drills up to 8mm thou I tend to turn up the RPM for drilling any way because of small drill size.

If you have Cam software that supports adaptive tool paths then use them because really suits these spindles with higher speeds n feeds and allows you to remove a good amount of material without stressing the spindle motor.

Regards the gumming up you are probably cutting to slow or even too shallow so your rubbing rather than cutting and overheating the tool. It's a common error people make when not used to cutting aluminum. Often They think it's the opposite and they are going too fast so slow it down or take even shallower cuts and it gets worse still.!!
That or you are trying to cut shitty 1050 series aluminum which is a nightmare to cut unless you cut through it in one go.?

It's a Similar thing with chatter.! . . don't slow it down, up the feed rate to push harder to increase tool pressure and it often goes away. Thou it's all a learning curve and each machine behaves slightly different and you tweak to suit.

Machines coming on nice..

[Chaz]

Yep, look up adaptive or tricordial milling - best for these type of machines. They arent made to 'hog' material.

[Nick]

Spindle - 2.2Kw, i'm using a mist cooler, pressurised coolant and air adjusted to make a large droplet mist. Aluminium all 6082

So it sounds like i'm doing a few things right but a lot wrong, i'm using adaptive tool paths in fusion.

The best success i've had is with 8mm 3 flute carbide end mill - 12000 RPM, feed 2.5 - 3m/min, DOC 5mm, WOC 20% this worked really well for a while but eventually it looked like it engaged a bit to much and stalled and broke.

I managed to break a 10mm end mill, similar settings, stalled really quickly (with hindsight i'm not sure why I did this). I've been using an aliexpress 12mm HSS rougher with good success recently with much smaller DOC to reduce load.

I've broken all my 3 flute 5mm /6mm end mills so far, best success was 16000 RPM, feed 1.2m/min, WOC 20%, DOC 2mm 0.025 feed per tooth.

I think your right with the rubbing, the chips didn't look very big with the 5/6mm cutters, i'm a bit concerned if I increase the RPM to 20-24k I would need to go at crazy feed rates? it looks scary going higher than 1m/min with a 5mm. What sort of feeds are you using at 24k RPM?

I could double the 5mm feed per tooth to 0.05, that would give 3m/min with 20k RPM? I could increase the RPM on the 8mm 3 flute: 16K RPM, 3.2m/min feed and reduce DOC?

[Chaz]

Avoid 3 flute - 2 flute or less for Alu - unless you user roughers like this which work very well - https://www.shop-apt.co.uk/3-flute-r...d-carbide.html - can go 8mm too - cheaper / easier.

HSS wont serve you well, dont bother with it.

2500 - 3000 mm/min is quick. I wonder if your spindle will bog down with this. the WOC is nice and narrow - you could try that at 10% with even a deeper DOC but Id runs slower feeds on that.

You are probably going to find that the problem is that you cant get the chips cleared - 3 flute is not as good (unless using a rougher as it breaks the chips into things that look like oversized dust).

Those feeds would work on 3 flute but chip evac is an issue.

At 24K RPM on something like a 6mm endmill (2 flute) Id run along at 1200-1500 with 20% WOC and a 10mm DOC. Endmills like working deep when doing adaptive paths - use all the of the cutting surface. Then work out how fast / wide you can go. The smaller the endmill the faster you need to spin. I'd never run your 2.2 KW under 24K RPM on Alu - no point. Dont be scared to feed quicker but only if you can get the chips out.

For 2 flute id be looking at this range - https://www.shop-apt.co.uk/end-mills...d-carbide.html - probably the 8mm or 10mm. Ditch the 3 flute stuff, its the main problem you are having.

[JAZZCNC]

Avoid 3 flute - 2 flute or less for Alu -

I'd never run your 2.2 KW under 24K RPM on Alu - no point. Ditch the 3 flute stuff, its the main problem you are having.

Oh Shit all these years I've been doing it wrong.!!! . . . . Silly me why be worried about tool life or finish quality just wap it up to full chat and let it go.!!