Okuma slow to start after weekend shutdown

[MTech2]

We have an Okuma captain L370M. When trying to start up on Mon. after being shut down for 2 days, it will not power up for at least 1/2 hour. I can turn main power on walk away, come back 30 min. later, reset main power and then it will allow the power up button to work. The operator says he allows it to power down correctly. Not sure why it happens "only" after longer shut down periods. Any ideas would be appreciated.

[78nova]

I am not familiar with your lathe but I am somewhat familiar with your symptoms. We have Okuma MC60H 5-axis Horizontal Mills that are 27 years old and still running...........somehow!

I can tell you this much. Our machines also do not like to be powered down for a length of time, like over the weekend. I cannot pinpoint why this is but I can attest to it happening. Seems mostly due to the circuit boards & individual axis power supplys.

What we do is when we are going to be down over the weekend is to leave the machine in auto and let it go into power save. There should be a parameter setting for this.

Through the week, we put our machines into a warmup cycle as we call it.

We built a small program to run the spindle @ 700 rpm & then we have a few X - Y - Z axis moves. It is a loop program so it just keeps repeating itself & we set the rapid override @ 5 %. If we have a tight tolerance job running we and we work on Saturday, we may just leave it in warm-up when we go home. This way on Monday morning we just crank up the rapid feedrate to 50% for a short while and then proceed with production. If it is a really tight job, we have a program we run to simulate actual part machining with no actual tools loaded into the spindle to help warm up the machine. We mainly see a big difference in our " Y " axis from a cold machine to a warmed up machine.

Just some notes to what we experience.

Good luck!

Kenny

[underthetire]

A capacitor in one of the power supplies I'd bet. After they finally cycle (warm up) they can start working again.