Work Around

[KylieandDany]

I'm using a spindle speed multiplier (5:1) in my Haas TM-1. I just picked up a job that will require many starts and stops with it, and I don't feel great about putting the high load from 0 to 2200 (0-11,000) RPM on the gearbox. Does anyone know if I can slow down the spindle acceleration rate in the controller? Or am I just being paranoid?

[behindpropeller]

There is no gearbox on the TM1, it is a belt.

[keebler303]

Originally Posted by behindpropeller There is no gearbox on the TM1, it is a belt.

He's talking about the gearbox on the speeder.

You could just step the speed up with short dwells in between to make a pseudo ramp.

Matt

[behindpropeller]

Originally Posted by keebler303 He's talking about the gearbox on the speeder. You could just step the speed up with short dwells in between to make a pseudo ramp. Matt

Thanks.... Sorry about that.

Could you make a subprogram which bumps the speed up?

[Geof]

Parameter 196: ACCELERATION LIMIT LOAD, factory set at 195.

You can change it to whatever you want.

This Parameter is also a good one to change if you are running from a power source with limited overload capacity such as a rotary converter or generator. It takes a bit longer for the spindle to get up to speed but it is difficult to notice the difference even when the Parameter is 100.

[KylieandDany]

Thanks Geof, I changed the setting from 195 down to 100, then 20, then 1. It made a huge effect on the spindle load meter... But, it didn't spool up to speed like I was thinking it would.

Went into Parameter 182 (SP Acceleration) was set to 2,000,000, changed it to 20,000. Spools up just like I wanted. Will that be ok for the motor? Thanks for the confidence to make parameter adjustments.

[Geof]

I don't know for sure about changing the acceleration Parameter but I guess if the motor spools up smoothly it is okay.

I guess what I was missing regarding changing the load parameter is that a mill spindle has very little inertia so it is going to spool up quickly even if the limit is quite low.

But I do wonder if your worries about loading your speeder gear box are justified.

Have you done any cuts with it yet?

What is your maximum spindle load at your heaviest cut?

For instance if the maximum spindle load at your heaviest cut is 20% then obviously the speeder gearbox can handle the spindle torque from a 20% load. So set the load limit to 20% and put the acceleration back to 2,000,000.

Now your cannot load the speeder gearbox any higher than in is loaded during cutting but you don't spend unnecessary time bringing the spindle up to speed.

It will not surprise me if you find that when you are actually taking a cut with the speeder you find the spindle load goes quite high quite easily. The 5 fold increase in rpm is matched by an output torque 1/5 of the spindle torque; which on a TM-1 is not high anyway.

[KylieandDany]

Should be making cuts in a couple of hours. I'm just engraving .010" deep, so actual cut load I'm not worried about.

Your point on speeder load is a good one. I'll go back to factory settings and check it out. Thanks again.

JS

[KylieandDany]

So, I'm engraving now, and all was good... until the end of the program and the spindle slammed on the brakes, and you can hear any/all backlash inside of the speeder head. I ended up changing parameter 182 (Accel) and 186 (Decel) from 2000000, to 75000. Now the spindle spools up, and spools down - nice and gentle. Probably takes two or three seconds to reach speed. I can live with that on these parts.
Thanks all. JS

[Wizzard of H]

You have probably found the best way to do this.
But don't forget to change those parameters back later.
Months from now, somebody will wonder why regular tools start and stop so slowly.