Startrite SD-31 planer overheating

[bobofsomerset]

Hi all,

I'm having a spot of bother with my recently-purchased Startrite SD-31 planer thicknesser. The motor is overheating and cutting out. I know it's high summer but I measured the temperature near the machine and it was 25-26 Celsius which I would imagine it should be able to cope with.

I was wondering if any of you folks had any experience with planer motors overheating and what can cause it, in the Startrite manual it says that a low voltage supply can be the problem (it is single phase). I have contacted Startrite (actually Record Power) and they have offered to send me a new motor but was wondering if it could be something else, before I commit to replacing the motor.

I suppose it's quite a simple machine and there are few things that could cause the motor to overheat rather than the motor itself, so it probably is the motor, but was just wondering if it might be the belt tension or something like that - actually there a slight smell of burning rubber and belt seems to have been throwing off a bit of rubber dust from itself.

I don't think that I am overloading it with timber and the blades are sharp.

Any ideas most appreciated,
Thank you.

 

[Trevanion]

Sounds like an electrical overload problem to me, Is the motor actually getting very hot to the touch to the point you can't hold onto it?

The motor may be working harder because the bearings are shot, which would also explain the heat as they would build up heat very quickly if they haven't got any grease and are worn out. Simple and inexpensive job to replace bearings. The motor will also be working harder if the bearings in the machine itself are shot as well.

Your overload protection in the switchgear may also not be adjusted correctly for the amperage of the motor which would cause it to trip prematurely if there's load.

It also could be the capacitor is shot and needs replacing which is another simple inexpensive job.

What's unlikely but could have happened is a winding is damaged and is shorting out and causing the motor overload to trip, this is a whole can of worms you really don't want to get into involving either a new motor or a re-wind. But this is rather unlikely if you haven't been absolutely thrashing the machine.

Take the belt off and try spinning the motor spindle by hand and listening carefully, any rattling or grinding noises from the motor means the bearings are gone, also if the spindle is stiff. Also, check the cutter block by spinning the end of the shaft, you shouldn't hear anything at all. If your belts are burning up that means either your pulleys are misaligned, the belts are too slack or the motor pulley is slipping a little trying to and keeping the cutter block up to speed, which would suggest knackered cutter block bearings.

I doubt the motor is completely knackered but it's not impossible, it's worth exhausting all the other, cheaper options first.

 

[bobofsomerset]

Thank you for that, I will investigate.

 

[Myfordman]

It is possible that the centrifugal switch is stuck/welded closed.

 

[AJB Temple]

If you bought it new, which it sounds like, just get supplier to deal with it under warranty.

 

[Clw]

I have this machine and had what sounds like a similar problem. After half an hour or so of continuous use it would cut out, which was extremely frustrating. Long story short seems like it was caused by my floor being like a crown green. I have the wheel kit in order to be able to move it to the middle of my shop so I can machine long boards, but move it back when only machining short lengths or to keep it out of the way. When the machine was at an angle across the slope of my floor I had this problem, looks, sounds and feels like overheating and with a badly worn belt. Record Power sent a new belt, but I've not had the problem since I make sure it's on a flat part of the floor when in use. The one time since January that I forgot and used it at an angle, after a short time it cut out.

So I guess my point is, check that the machine is on a flat surface before trying anything more drastic.

 

[bobofsomerset]

Thank you Clw,

That's interesting, I'm pretty sure my machine is on an sloping bit of the floor.

Also the motor seems to not be mounted level relative to the machine - in fact I think is sloping the same way as floor , making the angle even worse. Also having the motor pulley sloping slightly, would cause belt wear you would imagine. I might try to level the motor as well as the whole machine. Not sure, but maybe having the motor at an angle, as well as the entire machine, would cause the motor to be under more load (because of gyroscopic forces?) , hence overheating.

 

[sunnybob]

I dont know this particular machine, but it sounds like the drive belt is not vertical. If so, and its a traditional V belt, the belt will work its way to one side of the pulleys and create friction, and give a burning smell and also spray small bits of belt material all over the place. This will increase the load on the motor considerably, and if the motor has a thermal cutout it will stop working for up to half an hour before allowing a restart .

make sure the belt is vertical, adjust it so that on the longest straight run it has a maximum deflection of a 3/4" by pushing down then up with your thumb.
Make sure the motor pulley and the planer head pulley are EXACTLY in line with each other.
If as it seems, its brand new, its records problem, not yours.

 

[bobofsomerset]

I've levelled the motor, levelled the machine, drive belt seems Ok, and it's still overheating.

I don't think there's much else I can do, in terms of normal consumer adjustments, so I think that I will contact Record Power again, because of course, it is their problem really.