Hi guys,
just wondering if anyone else has issues with servos getting hot on long runs?
My X axis servo gets insanely hot on long runs.
have strapped on two computer CPU heatsinks which has solved the problem for now.
Y axis gets hot too, but the X will actually burn you if you touch it!
Adding the heatsinks has brought the temp down heaps and servo only gets warm now.
Is there a proper cooling arrangement available?
I have also needed to fan cool my post processor (Australia is a real hot country and the machine hates it!).
machine has not had a problem since adding fans and heatsinks.
on the processor, I used two 80mm 240v computer fans - mains powered so as not to place extra load on the powerpack.
Although ugly, machine runs great now!
Cheers,
Dave.
Hot Servos
Moderators: al wolford, sbk, Bob, Kayvon
Re: Hot Servos
Interesting thought on overheating motors Dave.
I have a second, 20 year old, non-Shark cnc that also runs hotter than I would like. I've been looking for ways to heat sink the motors as you have done.
I would be interested in seeing how you attached the sinks to your rig.
Also, what kind of heat sinks to use on a cylindrical surface.
Thanks,
Bob
I have a second, 20 year old, non-Shark cnc that also runs hotter than I would like. I've been looking for ways to heat sink the motors as you have done.
I would be interested in seeing how you attached the sinks to your rig.
Also, what kind of heat sinks to use on a cylindrical surface.
Thanks,
Bob
"Focus"
Antonie Van Leeuwenhoek (Developer of the microscope.)
Antonie Van Leeuwenhoek (Developer of the microscope.)
Re: Hot Servos
Hi Bob,
My machine has square bodied servo motors not steppers so attaching heatsinks was pretty easy.
I used 2 CPU heatsinks off some old AMD motherboards I had lying around, and an old 486 Mobo heatsink
A bit of thermal paste and a tie wire strap.
Worked a treat. motor only gets lukewarm now.
As for a round motor, maybe try a bunch of small Northbridge heatsinks and some thermal glue (not paste).
Really old computer boards have lots of small ones that should do the job (If you can find some)
I would attach a pic but I am trying to work out how (no attachment icon here
)
My machine has square bodied servo motors not steppers so attaching heatsinks was pretty easy.
I used 2 CPU heatsinks off some old AMD motherboards I had lying around, and an old 486 Mobo heatsink
A bit of thermal paste and a tie wire strap.
Worked a treat. motor only gets lukewarm now.
As for a round motor, maybe try a bunch of small Northbridge heatsinks and some thermal glue (not paste).
Really old computer boards have lots of small ones that should do the job (If you can find some)
I would attach a pic but I am trying to work out how (no attachment icon here
)Re: Hot Servos
The Sharks have always used stepper motors. Servo motors will also have some kind of encoder attached to it, and will have extra wires to the controller to repot the position info, so if your motors are using 4 wires only, they are most likely steppers.
Stepper motors in general are made to be able to run hot (like 150 deg F), but should not get so hot as to burn you if touched for a short period. If you find yourself needing to "heatsink" your motors, you may be giving them too much current for their windings and they may fail prematurely. The good news is they are cheap to replace.
Most controllers reduce the motor current when the motor is "holding" its position and not moving. That reduces heat build up. If you have a job that runs one axis heavily and while not moving the other a lot, the moving motor may get hotter than the stationary one. If you have a motor that is continually much hotter than the others, there may be a problem with the controller and how much current it is delivering to the motors. If your machine is in warranty, I would have the controller checked out.
Many 3rd part stepper drivers have adjustable current to be able to accommodate different power levels of motor. The popular Gecko G540 uses current setting resistors on the motors plugs to adjust the max current for each individual motor. I am not sure how this is adjusted (if possible) on the Shark controllers.
Stepper motors in general are made to be able to run hot (like 150 deg F), but should not get so hot as to burn you if touched for a short period. If you find yourself needing to "heatsink" your motors, you may be giving them too much current for their windings and they may fail prematurely. The good news is they are cheap to replace.
Most controllers reduce the motor current when the motor is "holding" its position and not moving. That reduces heat build up. If you have a job that runs one axis heavily and while not moving the other a lot, the moving motor may get hotter than the stationary one. If you have a motor that is continually much hotter than the others, there may be a problem with the controller and how much current it is delivering to the motors. If your machine is in warranty, I would have the controller checked out.
Many 3rd part stepper drivers have adjustable current to be able to accommodate different power levels of motor. The popular Gecko G540 uses current setting resistors on the motors plugs to adjust the max current for each individual motor. I am not sure how this is adjusted (if possible) on the Shark controllers.
Re: Hot Servos
Cheers Rungemach,
I have had concerns about my machine from day one.
Carbatech where I bought it from insists everything is o.k but I have my doubts.
They are the sole South Australian distributor I am aware of.
The machine makes horrible grinding noises and they swear this is normal!!!
When It came It was not assembled correctly, with bolts in the wrong spots.
the cradle mount bolts were way too long and projected out a full inch, some gantry bolts were missing.
When I complained to them they were not interested, and basically told me to sod off!
I am a woodmachinist by trade and have been operating and repairing machines for 28 years.
At work I run a Morbidelli Author 427.
I told them about the stepper problem and they told me it was not a stepper but a servo, and will cost me $150 each to replace.
So far I have had to fix everything myself. Not happy.
I thought using servos was unusual!
My machine is now out of warranty so the problems are all mine.
I will NEVER buy another tool from Carbatech. EVER. not even a piece of sandpaper lol!
I dare not run at speeds over 50% or the X axis slips and goes crazy.
So far only my experience in the trade has stopped a disaster from wrecking my machine.
I now hover over it like a new mother lol.
Dave.
I have had concerns about my machine from day one.
Carbatech where I bought it from insists everything is o.k but I have my doubts.
They are the sole South Australian distributor I am aware of.
The machine makes horrible grinding noises and they swear this is normal!!!
When It came It was not assembled correctly, with bolts in the wrong spots.
the cradle mount bolts were way too long and projected out a full inch, some gantry bolts were missing.
When I complained to them they were not interested, and basically told me to sod off!
I am a woodmachinist by trade and have been operating and repairing machines for 28 years.
At work I run a Morbidelli Author 427.
I told them about the stepper problem and they told me it was not a stepper but a servo, and will cost me $150 each to replace.
So far I have had to fix everything myself. Not happy.
I thought using servos was unusual!
My machine is now out of warranty so the problems are all mine.
I will NEVER buy another tool from Carbatech. EVER. not even a piece of sandpaper lol!
I dare not run at speeds over 50% or the X axis slips and goes crazy.
So far only my experience in the trade has stopped a disaster from wrecking my machine.
I now hover over it like a new mother lol.
Dave.
Re: Hot Servos
Rungemach
I should probably be clearer on what I said before:
My machine came semi pre-assembled.
the gantry bolts taped to the side were too short- they did not even go all the way through.
And there was only 8 there should be 12.
the cradle which was assembled had over long bolts poking out.
I reckon somebody mixed them up and put gantry bolts in the cradle.
I should probably be clearer on what I said before:
My machine came semi pre-assembled.
the gantry bolts taped to the side were too short- they did not even go all the way through.
And there was only 8 there should be 12.
the cradle which was assembled had over long bolts poking out.
I reckon somebody mixed them up and put gantry bolts in the cradle.
Re: Hot Servos
Long bolts holding the router down are for eventually adding the dust collector boot. If they aren't interfering with your access to the router then I'd leave them there for future applications.
Re: Hot Servos
4DThinker
True mate ,True.
But they should not be so long that they project into the toolpath!
made it hard to undo the collet.
A good inch past the nut on the underside is too much even for the boot.
and perhaps they might have been better poking up not down?
would do the same job without interfering with clamps or jigs, or getting in the way of the collet.
I changed them when one hooked on a board clamp.
True mate ,True.
But they should not be so long that they project into the toolpath!
made it hard to undo the collet.
A good inch past the nut on the underside is too much even for the boot.
and perhaps they might have been better poking up not down?
would do the same job without interfering with clamps or jigs, or getting in the way of the collet.
I changed them when one hooked on a board clamp.