electric motor question on my 5hp belsaw moulder/planer HELP!

Kelvin · December 26, 2008, 08:19:47 PM

Howdy all,

Well i got my new used moulder going and i was sooo happy to have the 5hp motor, i think its baldor, and its was making real nice crown molding with my new, used, grizzly powdered metal crown knives. (is this a crappy way to make moulding knives?) it set up easy and makes real nice smooth moulding. Thought it would be super hard with all the talk about how difficult to setup those 3 knives were.

Well i ran some moulding through and then i put my headphones on (i know) well i didn't hear the difference in the motor when i turned it on again, though i thought i heard something (alert!) This thing came without a switch so i had just wired a plug on the end to test it out, (big heavy wire cord, 8 gauge, though maybe 10) and hadn't got a big enough switch yet so i just was plugging in and running back and forth. Well. The last couple of feet i sent through, came out fine, but then when i went to turn back on, it would just buzzzz. Hmmmm.... well i went back to the machine to look and it smelled funny. I took the motor cover off and sure enough full of dripping oil. One of the caps vaporized for some reason.

Now i couldn't tell which it was. There are two start capacitors and two run capacitors, so i figured, well its not starting so i went and rumaged through my box of spare caps and what not and came up with two that were pretty close, a hair bigger in size. I wired them in and it started fine on my test. I thought, oh thats easy! Then tried to start again and "Buzzzzz" Aughhh!!!

Well i found two run caps to swap out and in the process of doing so found a loose wire and then i couldn't figure out where it came from. Assumed that the two sets of caps weren't connected so i put the wire were i thought it would go. Added two new run caps (again slightly bigger) and "buzzzz" or actually it sounds like its trying to turn over on 110v instead of 220v.

I have a twist lock plug which is 30 amps 220v (little light?) and the recepticle works fine on the other saws, so its definitely down stream of the recepticle. I took the plug appart, looked good, no arcing there. Then i decided, well maybe it doesn't like to start up without a switch so i found an old contact switch off my 3hp blower motor that said 30 amps and wired that in. Still nothing, but it does seem to build up quite an arc on the switch as it tries to turn over, that by the time i switch it off i see a pretty big flash inside the switch (not good i know)

Now i know i'm thinking of taking apart and bringing into the motor shop and mortgaging my house to pay the bench fees to find out something, but i wanted to see if there was any collective wisdom here before i took it out. The motor spins fine, no bearing issue. No arcs in the box. Wires look good inside motor that i can see. Moulder head spins easily so no binding there, but it sounds like something won't let the motor spin. Maybe previous owner had to small of start caps in there? Why did it work for so long? They look factory. The motor looks real nice and clean, not much monkeying with the bolts and internals. I guess i should try resistance on the motor wire leads for shorts, but darn, what would make a cap boil over all of a sudden? Hmmm..... Any other tests or things to check? I'm not certain the wiring is correct anymore, but i don't see how it would be different. Anyone have a schematic on something like this 5hp? Nothing on the motor plate to show me. What would you think? I spent a whole half of day on this trying everything i could think up. 4 hours of goofing off. Man i hate that when you can't find the darn thing.

thanks for any ideas, hope all had a good X-mas time. Boy those stores are scary. Glad i made all my presents out in my woodshop!
See you all,

KP

Fla._Deadheader · December 26, 2008, 08:34:05 PM

Tomorrow, I could go look at mine, and do a sketch of the wiring. I had to replace a Cap in mine. No big deal ???

tyb525 · December 26, 2008, 08:36:25 PM

Asked my dad, who is an electrician, and he said he thought the start circuit is bad, or somehow its only getting 110 to the start capacitors and the run capacitors aren't getting any electricity.

Fla._Deadheader · December 27, 2008, 09:06:34 AM

Well Kelvin. Bad news. My motor has a Bakelite block, which has 1 power lead going in and out, and 5 Capacitors. It is a rats nest of wires, and NO lead tags on any wires, for ID ??? LOTS of wire nuts ??? >:( >:(

I have a cap going out, and, will have to be EXTREMELY careful, to not mess up.

Sorry I couldn't be of any help.

I DO have a manual, but, don't know if it shows the wiring for the motor. I will try to dig it out, today.

Gary_C · December 27, 2008, 09:30:59 AM

With the trouble you are having, I would guess the start windings are bad. Even if the broken wire started the trouble chances are the windings have been damaged when you have been hearing that buzzing. I would say that motor needs to go to a motor shop to be saved and even then if the start windings are bad there is no hope for repair. A good motor shop can check the motor and see if the windings are OK before anything is done.

The only other way to fix, is to take the motor apart and replace the start switch, repair all wires, replace all capacitors, make sure it is wired correctly, and it would be good to go, that is if the windings are not bad. You take your chances, but I would say it is not a good bet that it will run.

cheyenne · December 27, 2008, 05:36:55 PM

If it were me I'd just go to Graingers and get a new one. Be cheaper in the long run....Cheyenne

Ironwood · December 28, 2008, 07:29:25 AM

If it is a heavy cast "frame" keep it and get it rebuilt/ fixed. Most current motors are steel outer frames and aren't the same quality. I think you may have fried the one field or winding and capacitors wile enjoying your music. Take it in and get it serviced. I guess I am lucky, our local shop is super friendly and reasonable, although he makes his bread and butter on the industrial stuff 50-200 HP, so we just have to be patient. He scrambles daily for the local hospitals, and big industry. Our "little stuff" is fun.

Ironwood

Kelvin · December 28, 2008, 08:45:00 AM

Thanks guys,
I'll take it in and see what they say. I've got a few spare 5hp motors i've collected for this type of problem, but i thought this baldor was really good, so i'll see what to do. I've bought two of these moulders for $225 each, so paying $400 for a new motor isn't really going to be fun. I may just wait for another used machine and just use my other one. Though i'd like to understand what happened so if its operator error (to small of elec wire, switch.... etc) i'd like to know for the future. I've got a lot of years ahead of me to be wrecking motors in.
Thanks all,
kelvin

Ironwood · December 28, 2008, 01:10:30 PM

Baldor is a good motor, but even they have succomed to steel sleeve frames. I perfer the cast ones w/ fins for cooling.

Ironwood

VT · December 28, 2008, 07:42:46 PM

Take apart , mark all areas of the frame and outers , check the contact points so the start up windings are powered up when needed. After long sits , this centrifugal switching seizes in run.

This is easier than a chainsaw ..

Any stamped numbers on the frame , could lead me to more info..

VT

Kelvin · December 29, 2008, 06:55:12 AM

Howdy VT,
This sounds hopeful. I'll take apart soon to at least see if there is any obvious arcing from burn out. I'll see about the numbers, and if i can figure out what parts you are refering to once i get it apart.
Thanks
Kelvin

VT · December 30, 2008, 12:01:08 AM

Kelvin,

part numbers or and numbers leads one to frame size etc.
Then Baldor and do a search for stuff, but you MUST have some info to start.
There are thousands of Motor type that Baldor makes.

Anyhoos , mark well , digital camera on the tear down and always mark along the way. Wire windings should all have the same colours , if you see some real dark , then smell , if it smells like my cooking , somethings wrong , And All caps are not the same , the numbers on them are for the same reason as all parts.

VT

sawdust · December 30, 2008, 01:10:15 PM

kelvin before you pull it all apart, disconnect all the wires from each other in the junction box. Keep track of what was connected where. Use a continuity tester and check each lead for a short between the ground and the wires. This will indicate a melted wire.

dc

Dan_Shade · December 30, 2008, 02:55:23 PM

just stating the obvious, but be careful with those caps in there, they can zap you.

sawdust · December 30, 2008, 03:43:15 PM

Thank you Dan for pointing that out, my brain was on three phase. no caps.

Kelvin · December 30, 2008, 04:24:20 PM

Yeah, i've wondered about the caps discharging. Does it take metal crossing the contacts? Are they always ready to go? Not sure exactly how they work, kinda like a coil on a car?
Thanks
Kelvin

sawdust · December 30, 2008, 04:34:49 PM

metal will do it. No idea how long they will hold a charge. My RPC has a resistor built into it so it will discharge any "leftover" power.

tyb525 · December 30, 2008, 07:00:08 PM

Capacitors don't hold a charge for too long, but it also depends on the type. It wouldn't be a good idea to touch them soon after running it.

olyman · January 02, 2009, 03:40:57 PM

kevin--puuurrsonally!!--id take it to a motor shop--if you have one close thats reasonable--they can straighten it out--and baldor is a good motor---dont want to ruin it!!

woodhaven · January 02, 2009, 04:28:41 PM

Kelvin.
If it sounds like it is trying to run on 120 volts maybe it is. Have you checked
the current with a meter ? A 240 motor will try to start on 120. Check your
voltage and make sure it may be as simple as a blown fuse or breaker.
Remember on a breaker you need to turn it off completly then back on.