[jdunn]

I think im sure I have tuned my motors up as far as they can go. They are 1600 oz/in 1.8 degree steppers being driven by dm860a drivers and 48v power supplies. My lead screws now are 5/8"-6 and 1/2"-10. the fastest i can get my ipm in mach is around 20. I did run driver test and change kernal speed but no improvment after retuning motors. I would love to upload my .xml but i guess the only way to do that is to zip it up right. Anyone have any ideas.
I thought maybe resonance, maybe just slow motors, the machine(diy) slides nice by hand and leads turn really nice and nothing binds.

[neilw20]

Interestingly, in the specs I don't see maximum clock rate.
You need to see how well the driver is matched to the motor.
You might have the micro steps set too fine. That can limit your speed.
Once you have optimal settings for the motor/driver combination, the only way to make it faster is to run at a higher voltage.
You need to take the motor inductance into consideration as well.
Some high inductance motors require very high supply voltages, way past what your driver can handle. (80v, but do confirm that) to get much speed.
Post the specs for the motor and the driver and some nice person will calculate what you can possibly achieve for a given range of supply voltages.

[jdunn]

thank you Neilw20 for the reply. Kernal speed is set for 65000Hz. Motors are nema 34, 1600 oz/in, 5.7volt, 3.2amp, 1.9ohm phase, 22 mH inductance. The drivers are rated to 7.8amp peak. They are set to 1/8 step . And yes the drivers max out at 80volts

[jdunn]

Am i correct in thinking that if i reduce the number of micro steps it would require less kernal speed

[neilw20]

Have a play with the settings and start off with say 1/4 step.
No point in having the KHz higher than you need, but you don't want it too low either.
Read this and plug some numbers into the formulas. It is a good starting point for you.
Support

[jdunn]

Great. Thank you. I will read it .

[ger21]

You've got more than one issue here.
Unfortunately, what you really need to do is get different motors and drives. What you bought is simply not capable of spinning very fast. To get the most out of those motors, you'd need a 150V power supply.
You're also using 1/2-10, which requires extremely high speed to get good performance.

If you look through the "Big Bamboo" thread, he started with the same or similar motors to you, only he was using ballscrews.
First, he switched the drives to Geckos, which doubled his performance. Then, he replaced the motors with 400oz motors, which improved performance by about 5x.

The cheapest option you have would probably be to switch to 1/2-8 8 start acme (1 turn/inch). But with those motors, I don't know if you'll ever really be happy with the performance.

[neilw20]

Told you someone would pipe up with good information.
My voltage guess was right.

[victorofga]

i think they are doublestack motors..
powersupply sure need larger..

screws, the 5/8-6 would be ok about 120-180 ipm, the 1/2-10 i believe the max about 80 ipm..

for those motors, 1600... i think you could use 10 mm lead.... 2.5 turn per inch.. and you get the 300 ipm easyly..
on ebay you can get some for good price..

but this all , will cost extra..

[jdunn]

Ok, Back from the weekend. I read the whole BIG BAMBOO thread, love the bamboo. We use it alot as flooring and especially countertops around here.
After reading and cross referencing everything, i came away prepaired to get the g203v as a first step and then second getting 72 v power supplies. As far as the lead screw goes, and taking whip into consideration( I have 16"x24" max travel) i decided i would try changing the gear ratio instead of the screws. My x/a(slaved) is 5/8"-6 1 , 40" long, the y axis is 1/2"-10 1 and 26" long, z axis sis 1/2"-10 as well and only 14" long so I wasnt to concerned about the whip at the rpms it would be spinning. I did a test on my lathe and could spin those lengths way way faster than they would be spinning for my application before they whipped.(I do realize its about more than just whip,(heat , friction , virbation ect) and that the screws/nuts will wear faster. I do in the end end think I will be replacing the leads but will have to really research to find one that will match the motors and rpm better. My gantry over all weight is about 90 pounds.
However in the end, something in the gecko link about damping caught my eye and i checked into it alittle more and guess what, i ended up get me some hockey pucks. It worked. Of course i was skeptical alittle. Irebuilt an old ford 460 engine not too long ago and it had a pretty good size damper on it. Steel ring to go around the shaft, then rubber around that , then another heavier steel ring aound that. Hockey pucks weighed 5.5oz each. I only bought two to start with, they only had the ones with the team logos printed on em around here($5.99 each). I put one on x and one on a because those were my most problem and loudest axis. Anyway amazing results right of the bat, so far 14.3oz seems to be good each for those two motors. I added weight until it was too much and then took it off till it didnt work and went to the middle of those results. Also if anyone has bigger shaft motors they wanna try this on, get a roll of duck tape, (i had acouple of already open rolls so i didnt have to waist so much) the hockey puck fit really snug inside the roll. inceasing the weight overall. And to lower the weight you just unroll some tape and reweigh. When u go to ballance them the weights go inside the rim of the roll. they overall dampers/flywheel only stick out alittle more than the nema 34s. So you gotta have like at least the diameter clearance of the hockey puck or tape if you add more weight.
No ,more vibrations, i can jog through all the different speeds with out vibrations(which i assume would be caused by resonance) and the speed inceaseis awsome. When from 19 to over 100 in mach3 motor tuning. Drivers are running 1/8 step. Actually mach3 said i could not go any faster because my kernel speed was too low. Which is maxed out at 65000. Driver test said everything was fine at higher kernel speeds but when i try to set anything higher than 65000 when i go to restart the program it crashes/freezes. Then wont load my profile. I open the .xml in word and edit the pulse speed and resave it. Then mach will open it again.
Right now z axis is my limiting factor for speed when cutting, I heard that it will only go as fast as the slowest axis i have it set low cuz I am not used to how fast it moves now and still have the worries its gonna crash, so untill that goes away.
I am a professional cabinet maker and have used routers and all related carbide tooloing for yyyyeeeaarrrsss. However, we only use our ears and end results to tell if the feed speed is to fast or slow. So to have to put a quantitive number behind feed speeds is hard for me now. I have been test machinre with 1/4" prefinished maple ply. 1/4/ solide carbide freud upcut spiral, .125" per pass at 25.25 ipm waterline and 37.5 ipm pencil and by ear that seems to be the max for the cutter rpm. Does that sound about right.? Really nice cuts, no splintering, just alittle fuzz. less than 1/32 long. No more burning or discolored cutter. Yes i am using pc890 ROUTER. I nmade a special base that redirects the vent air upwards and engineered enough room in the spindle hole so some of vent air blows down and pushes dust towards the dust collection.

[jdunn]

Also in the process of motor tuning i changed the amp setting on my drivers(lowered it) and the motors barely even get warm now.

[ger21]

At the lowest rpm setting on an 890, you should be cutting at least 100ipm for best tool life. But at higher speeds, an upsut spiral will cause chipping on plywood.