Random Erratic Possible Stalling Problem with router

Hi Guys,

I have an annoying issue with my router in that it loses position with the resulting tossing of the work piece!!

This does not happen all the time and when making signs which is 90% of my work it does not normally occur at all probably because of the short duration of the job. I have been cutting some 'pixie doors' for my granddaughter and the problem is apparent as the job runs for approx. 2hrs.

I thought I had got rid of the problem as I had a faulty USB cable, so replaced with a quality double shielded one! but oh no - the job runs through the roughing stage that's takes 30min no problem (at the moment) I ran the finishing job twice - the first time it failed after 5 minutes and the second time after approx. 60 minutes. The first time it lost position on the x-axis by about 2cm I ran the job from the start again and the second time it failed it was the y-axis and it lost position by about 6cm.

I thought the job would fail at some point so videoed the second run, reading on the forum I think the stepper is stalling and should probably lower the feed rate. I would appreciate any feedback on the video of the problem!!!

Earle
https://www.youtube.com/watch?v=zlcY5tGO0VY

It looks to me is that the Z is stalling. It could be that a driver is heating up and shutting down.
What drivers are you using and what is the voltage of your PS. Can you give more info and pic of the machine. ..Clive

Hi Clive, thanks for your comment, the router is a Chinese 6040, the ps is 24v and the drivers are YOC335. Feed rate for tool is 20mm/sec or 1.2m/min


I know this is generic Chinese stuff and I know some people's views on this type of machine but hey I have learnt so much I feel that I could now confidently build something more permanent!


following the fail in the video I did a goto zero and the y -axis had lost position by about 6/7cm, the up and down movement of the spindle I think is the z-axis doing the correct profile moves as there is a lot of detail in the job.

I found a few of these drivers for sale but no technical details with a quick Google. Like Clive, I would suspect driver overheating, assuming that obvious things like physical jamming have been ruled out. I saw a very similar set of symptoms when I was setting up my 3D printer; the drivers would just shut down when they overheated and start up again once cooled. Given that your cutting loads are probably quite low, you could try winding the max motor current down a bit, and also check that the motor static current is set to half - if the drivers support these functions... At least, this should be easy to try.

I'm guessing that the machine stalls in different places each time, so physical jamming seems unlikely, but if you can disconnect the steppers easily it might be worth doing so and checking that the slides move smoothly.

After that - interference/noise, bad connection, etc - all much more difficult to track down :frown:

Thanks Neale,

When I bought the machine I changed all of the wiring. Created correct earth paths etc - so hopefully got that one covered!! I also installed a UC100 and a different BOB!

I have stripped the hardware down and checked for any possible seizing but everything seems fine and moves easily.

I will look into your suggestions to see if that's possible! will report back....


Earle

Quote:

---

Originally Posted by Earle

Thanks Neale,

When I bought the machine I changed all of the wiring. Created correct earth paths etc - so hopefully got that one covered!! I also installed a UC100 and a different BOB!

I have stripped the hardware down and checked for any possible seizing but everything seems fine and moves easily.

I will look into your suggestions to see if that's possible! will report back....


Earle

---

Are you by any chance running this on a laptop. In my opinion USB can give quite a few problems. ..Clive

Hi Clive and Neale,

Thanks for your input, Clive I am running this from a dedicated machine!

Neale, I have changed the max current on the drivers from 3.5A to 2A and the job ran all the way through both the roughcut 30mins and the finish 1h35m YIPPEE...........

Ok, so without getting too excited as I obviously will try the job again to prove a cure, but what are the consequences for the machine of me reducing the max current through the driver?

Would it be worth me stripping the driver apart to make sure that the chips are heat sinked correctly?

Earle

Quote:

---

Originally Posted by Earle

Hi Clive and Neale,

Thanks for your input, Clive I am running this from a dedicated machine!

Neale, I have changed the max current on the drivers from 3.5A to 2A and the job ran all the way through both the roughcut 30mins and the finish 1h35m YIPPEE...........

Ok, so without getting too excited as I obviously will try the job again to prove a cure, but what are the consequences for the machine of me reducing the max current through the driver?

Would it be worth me stripping the driver apart to make sure that the chips are heat sinked correctly?

Earle

---

Earle It will depend on the load you put the machine under ie bigger dia tools or DOC feed rate etc. I am sure your machine would benefit from better drivers with a higher voltage PS supply. It looks like the drivers were overheating and shutting down. ..Clive

Clive,

I have a design for a new machine, but I think I will probably build a new electronics package anyway, then I can sell this machine on as a complete working system.

thanks for yours and Neale's help

Quote:

---

Originally Posted by Earle

Clive,

I have a design for a new machine, but I think I will probably build a new electronics package anyway, then I can sell this machine on as a complete working system.

thanks for yours and Neale's help

---

Ok Earle that's all good. Don't buy any electronics as a Kit as they are very rarely matched, You would do betting putting up some drawings for others to critique . Good luck with your new build. ..Clive

Lower motor current translates into less torque available from the steppers, so potentially lower max speeds and acceleration. The only way to find out is by testing - run a series of tests involving faster and faster speeds, checking that the spindle always returns to the same point. Back off a bit from the fastest working speed to give a bit of leeway. Then ditto varying acceleration. In your case, you might look for higher acceleration at the expense of speed, as with fine work you seldom get up to full speed anyway. That's one reason why no-one can give you hard-and-fast numbers - not only do machines vary but so does the kind of work done.

Good luck!

A lot of people that buy the 6040 machines scrap all the electronics from the start, and replace them with quality components. That saves all of the aggravation you'll go through trying to get the machine to work with the stock electronics, until they fail and you replace them anyway.

Update:

i would like like to thank the contributors to this thread. I have run many jobs recently and just run several jobs for clients that have taken 4.5hrs plus each without any failures hitches etc.

so it appears that lowering the current setting on the drivers has completely solved the reliability issue that I had, the relief is palpable ;-))

earle

Quote:

---

Originally Posted by Earle

Update:

i would like like to thank the contributors to this thread. I have run many jobs recently and just run several jobs for clients that have taken 4.5hrs plus each without any failures hitches etc.

so it appears that lowering the current setting on the drivers has completely solved the reliability issue that I had, the relief is palpable ;-))

earle

---

Ok Earle that's good news I would change out the electronics when you can with a higher voltage p.s. it will then be a different machine:eagerness: