Strike CNC (My first CNC router)

[Shinobiwan]

As with everything we sell, returns are accepted.

Thanks Gary. I'm not ready to throw in the towel just yet but its good to know if I can't resolve whatever it is that's causing the noise I can at least swap the drivers for something else.

[Gary]

Set the current to either 3.6 or 4.6A, but start at 3.6A peak.
see if this solves the noise problem?
Regarding the software problem, this could be noise? make sure the RS232 cable is away from any power cables, and also make sure that your signal cables (Step, direction and enable) are well away from any power cables like the motor and the power supply cables. I cant see in the picture if you have done this. Also are the motor power cables shielded? and grounded at one end?

[Shinobiwan]

Have you tried another driver? is the problem with one driver?

The noise is on all 4 steppers.

is your version of windows 32 or 64 bit?

XP 32bit fresh install with only mach installed

did you do the tuning without any load on the motor shaft (Disconnected from the ballscrew?)

A bit of both. 2 steppers (the Y and Z) are connect to the ballscrews and the dual steppers for the X are without.

What is the motor?

Nema 23 4Nm (8 lead type) on the X and Y. The Z is a Nema 23 3Nm.

do you have the dasheet

Have the datasheet from your webshop.

how are you connecting (Series or parallel) and what is the current set to?

Parallel wired and I've tried the current on the default (DIP 1,2,3=ON) and also 3.93A RMS (DIP 1 & 2=ON, 3=OFF)

[Gary]

They are not our motors, we dont sell 4Nm motors (Nema 24) if the current is 4A, then you need to set this to the peak value not the RMS.
if you are setting to 4A RMS, the motors will most likley burn out, and may be the cause of the excess noise?

[Shinobiwan]

OK result! The software is now working.

Took hours of faffing around and the solution wasn't clear at all!

Just in case anyone else runs into the error "Selected collating sequence not supported by the operating system." When trying to read or write data to the drives. Here's how I fixed it. You need to enable multi language within XP. Be sure your regional settings are English(UK) and then select the check boxes for Thai and also East Asian language support. And that's pretty much it. No idea why I had to do this but it refused to work without those options.

I've managed to eliminate the noise using manual setup but the autoset function brings it back. Seems that too high a Kp value increases the noise. The autoset function wants to set it around 2000 but to get the steppers silent you really need to be around 700. This value seems suboptimal as the rise time is fairly lax. Seems I have shite motors? Weird because the 3Nm behaves the same as 4Nm too, you'd think there'd be some difference unless they're both from the same manufacturer.

Anyway the drives are working well now so I'm happy there.

What's less good is the fact that Strike CNC have messed up on replacement parts and there's some binding issues in the Y and Z ballscrews. There's loose bolts, rail slides that haven't had their tension adjusted, missing screws from motor mounts, cock-eyed mounting of the supported rails on the Z front plate, damaged bearing in the floating end Z ballscrew support. AND that's in the replacement gantry that was supposed to fix all the other problems I had in the first one.

Now I've got strip the Z axis down, check and loctite every bolt. Thank god I've got the help of Dean because if I hadn't I'd have given up and cut my loses. The guy has spent hours on the phone and a couple of trips here and for virtually nothing. A true asset to the community.

[Shinobiwan]

OK here's some shots of the problems with Strikes replacement Gantry.

[Shinobiwan]

Btw is it essential to have the ballscrew floating end mount on? The bearing is damaged and I figure it isn't really needed for such a short ballscrew since its supported at the fixed end and the ballnut?

[m_c]

Btw is it essential to have the ballscrew floating end mount on? The bearing is damaged and I figure it isn't really needed for such a short ballscrew since its supported at the fixed end and the ballnut?

Probably not.
The support bearings purpose in life is to support long screws from bending under thier own weight, and/or to stop screws from whipping when spun at speed.
If the screw is short enough/not spun fast enough that whipping is going to be an issue, and it's not long enough/mounted in a way it's own weight could bend it (i.e. hung vertically), then you don't need one.

I'm sure Jonathan will be along shortly with the required calcs for working out the theoretical critical/whipping speed (or just search for his posts, as he's covered it before)

[Jonathan]

Agree with what m_c said. You can find the formula he suggested by searching for screw critical speed on google, but assuming the ballscrew is 350mm long the critical speed is 3500rpm - so 3500*5=17.5m/min. The formula isn't that accurate, but that's a huge amount more than you'll ever get on the Z-axis so you're fine to run it. It's <£2 for the bearing you need on eBay, so it's not much loss to get a new one, not that you should have to pay for it anyway.

This thread is the first result on Google for 'Strike CNC', so I wonder how long it will be until they re-brand!

I doubt they will go out of business soon, as it's so easy for these companies to blatantly lie about their products:

http://strikecncrouters.com/page2.htm

[Shinobiwan]

Agree with what m_c said. You can find the formula he suggested by searching for screw critical speed on google, but assuming the ballscrew is 350mm long the critical speed is 3500rpm - so 3500*5=17.5m/min. The formula isn't that accurate, but that's a huge amount more than you'll ever get on the Z-axis so you're fine to run it. It's <£2 for the bearing you need on eBay, so it's not much loss to get a new one, not that you should have to pay for it anyway.

This thread is the first result on Google for 'Strike CNC', so I wonder how long it will be until they re-brand!

I doubt they will go out of business soon, as it's so easy for these companies to blatantly lie about their products:

http://strikecncrouters.com/page2.htm

Not to worry Jonathan. If you lay too many bad eggs eventually it'll make a stink.

I'm not the only unhappy customer

http://www.cnczone.com/forums/europe...nc_please.html

In particular this comment from that customer rings very true:

"On receiving my machine (the eBay service was great!), I found that the build quality was terrible....really terrible. Basically, I have completely rebuilt the machine, adding a host of parts that I made to strengthen and support the various axes. Most of the extrusions and support rails were not bolted correctly and the stepper motor mounts looked like they'd been chewed instead of machined!

However, I found that the price paid was actually not that bad, when used as a basis for a new machine, but you would most definitely need to at leat check the build quality or better still, strip it down completely."