Thread: Carbatec wide drum sander

Perhaps you need to determine why the motor is getting too hot before considering a replacement.

Is the drum sander gummed up with dust and loading down the motor?

Lack of ventilation around the motor? Also including caked dust on the motor windings.

Is it a faulty thermal detection device?

What happens if you run the motor with the drum sander disconnected?

Thanks woodborer,
Yep done all that. Good belt, drum rotates freely, using a dust extractor, motor is a sealed unit, but I can't test the thermal overload switch.
On no load it runs for a minute or so then shuts down. Motor gets warmish but you can still put your hand on it.

May well be the thermal overload switch.
But I'm suspecting a possible winding fault is causing it to heat up so quickly.

Spoke to a person at Carbatec. He reckons it might be the centripital switch sticking.
Apparently that can cause my symptoms. (I thought it was a straight capacitive start without the centripital part).
So I'll pull it apart and have a look and see if a good clean and lube with electrical grease will fix it. If not it's off to the electrical repairers to see if they can fix it or not.
Hopefully the household insurance will cover it.

Well more info.
Pulled it apart this arvo and found that the centripital switch is working fine. The motor spins very well and is nice and smooth ie its' bearings are fine.
Same can't be said for the drum brearings. While I thought they were OK that was just watching the drum spinning with the motor. When off the motor they are not real good. Fairly tight and not free spinning at all.
So pulling it apart was the easy bit. How on earth do I get those drum bearings off.
Do I need to press them off or will they just tap of with a judicious bit of hammering?

Can u post a pic of the drum/bearings?
Pete

Got them off. The bearing on the motor end came off fairly easily, without a bearing puller. The othe end (outside end of drum) had to have a puller used on it and it was TIGHT!
Both bearings are a 6205 sealed ball bearing and are relatively cheap about $10.

So I'll give all parts a good clean and dry then re-assemble with new bearings and then tune it up and give it a go.

Originally Posted by Lyle

Got them off. The bearing on the motor end came off fairly easily, without a bearing puller. The othe end (outside end of drum) had to have a puller used on it and it was TIGHT!
Both bearings are a 6205 sealed ball bearing and are relatively cheap about $10.

So I'll give all parts a good clean and dry then re-assemble with new bearings and then tune it up and give it a go.

If you can buy the 2RS type, 2 rubber seals, they last a lot longer in that dusty environment. Got them on the bandsaw blade guides, can't remember the last time I replaced them.

When you get it back together use a meter to see if you have full power at the motor switch. If your line is too long you could have a loss of power depending on the wire size. If you are using an extension cord you will have a loss of power. Both can cause the moter to run slow and hot tripping the breaker. This is a common problem . I know all the power there is 220 V. It uses half the amps as our 110 V. We use 220 for large HP moters because it uses half of the amps and the wiring size can be less. You should not have a drop in power but it does not hurt to check. The berring price seems very cheep to me. Good berrings are much more expensive. I would not put berings from China in anything. Berrings form England, Japan, Germany and US are a thousand percent better. (I am sure if you can use Australian berring whey would be just as good.) They cost more but the quality is about as far apart as you can get. Your sander has a lot of force on your berrings and cheap ones will fail fast.

Remember a drum sander is for finish work. It is not a planer. It is not designed to resize wood. You might be over working your machine. The big 52 inch machines can run all day but the little machines have huge limitations. If you are trying to take off more than 10 or more mm's you are using the wrong machine. The drum sander is for clean up only.

I hate when I ware things out. I expect them to last forever.

If you need to buy a new moter I would go with an American moter. They are better than European moter. Even the European machine manifactures are starting to use US moters. They run smoother and better when the electic current varries around the world. If you can get a moter from the Jet company you will be fine. I am not sure where thier moters are made but I have 5 pieces of equipment from them and they are very good smooth moters. Delta is another good brand. I know they sell there under a different brand. Is it Carbitec? I have seen it there but forgotten.

I hope you don't need to spend a lot of money fixing your machine. A good used moter is another way to go. Stuck berrings and low voltage can burn out a moter in short order. If you have a drop in voltage I would check for a loose connection. If you are using an extention I would plug it into the outlet direct and then check it. . If that all fails and all is right then it is time to replace the moter.

Hope this helps.
Chris

Thanks Hobo.
Got the sander back together today and tuned it up. Used some accuract shims. I reckon there is less than 1/4 mm end to end (across the drum). Runs very smoothly now. I had to play with the bearing cap bolts to get the freedom of spin that I reckoned was right. If you tightened the bearing cap bolts too much the drum would get a lot of resistance. I checked that the bearings were seated correctly on the shaft. A bit of a design fault not using self aligning bearing housings. But that would eat into the cost to produce.

Anyway the machine is up and running better than it has been for ages.
Thanks all for your inputs.

well done Lyle. I found this a very interesting thread. The other problem I was going to mention was the ambient temperature inside your shed. That could also be a long term problem.

Anyways, did you do anything to improved the original situation to make sure it does not occur again, like dust proof bearings and seals etc?

Not really. I think most of the problem lay in the fact that my father-in-law used it without dust extraction. The machine was a mess.
I pulled it apart and gave it all a good clean. Replaced bearings in the drum, as the motor was in good condition.

After replacing the bearings in the drum I had to fiddle to get the minimal rotational resistance I could. The bearing caps just took a 1/4 turn too much and they started to bind up the rotation. So I'd let them off a bit and re-adjust. I used locktite on the cap bolt threads to ensure once I got the resistance OK they'd not shift.

Adjusted the parallel-ness of the drum using good shims and am now very happy.

Used it to smooth out some 6" boards and it performed very well, little heating of the motor and the tickness across the boards was within 1/64", good enough for me.

Good on you Lyle for persevering _and saving the pennies.

This has been a beaut thread with lots of good pointers and information for anyone who cares to read it. Hobo's suggestion was one I hadn't considered. Much of what has been described and fixed here applies to all sorts of machinery.