Having trouble dissassembling a new ST-15

[rleonard]

I spun up my new ST-15 generator last night.  Bearings are quite noisy so I want to do a repack and inspect.  I have the end bells loose but they are stuck on the shaft.  Soaking in penetrating oil now.  I did get the drive side bearing to move a wee bit but then it stopped too.  Suggestions?

Bob

[rleonard]

Got it!  I rigged up a couple of large C Clamps, a bar and a spacer.  Then I could tighten the clamps and pull the housing off.  This setup kept the reactive forces close to the center and not out at the edge of the casting.

Bob

[Doug]

Wigle the one opposit the cooling fan off. This might be a figh use heat and swearing......
Drop the rotor from no more than 4 inch on a hard wood block to loosen the other end bell off.

Don't repack, scrap and buy new FAGs or SKFs.

I wrote a post on this a few weeks back explaining this if you can't find it I'll retype it.

Doug

[Geno]

I think this is the post Doug is referring to. Shop around for bearings. I found the prices vary greatly. Applied Industrial was the best and had them on the shelf.

http://listerengine.com/smf/index.php?topic=415.0

Thanks, Geno

[rleonard]

Thanks Guys.  Will go bearing shopping today

Bob

[Doug]

As a last resort, consider brining this to an electric motor rewind shop.
I doubt they would charge you any more than 40 bucks + bearings and most likely they get a better deal on bearings than you can so it may be worth your while. Look for the EASA member logo on the door know your dealing with good people. There absolutely no harm in having pros do this and you get the added peice of mind that they know how to check the bearing fits

I would also seriously consider having them do a hot/bake dip on your stator. My gut feeling is the Chinese do one cold dip assemble/bake and ship these out. This won't cost you much, but if you don't want to spend the money the old DIY with Glyptal 1201 should be done when ever you open up a rotating machine just to ensure you haven't damaged the varnish and to prevent corrosion.

Doug

[dkwflight]

Hi
I just talked to a big motor shop(industrial) about my 20k st head. For a dip, rotor balance and premium bearings---$800.00---GASP!

My recomendation is do the bearings and run it under a light load, two 100watt bulbs for sevreal hours to bake any moisture out.

Borrow a Megger to check the insulation quality.
A refrigeration supply company is where I bought mine, around $100. I use it at work for a/c repair.
Maybe a small shop would be cheaper.
good luck
Dennis

[Doug]

800 bucks!!!!!!

Thats insaine!!!!!!!!

I left the buisness because it was shrinking at 3% a year because of cheap imported motor, to cheap to repair.
Sad to see people are extorting the remaining buisness to stay a float.

$ 800.00, when I left the buisness 12 years ago that was just about enough to cover the cost of winding a small motor and buy a new set of bearings......

This isn't right call some shops for quotes before you deal with clowns who ask for crap like this....

Other thoughts:
Brings in a clean dry Stator only for the dip and do the clean up your self ( about a half hour of scraping the excess out ) .
Buy your own can of PD George air dry varnish, thin it with xylene and paint on with a brush with several coats.

$800.00 bucks that makes me sick!

Doug

[dkwflight]

Hi Doug
I thought about doing something like that for my st head. The windings are in there so neatly done. I wanted to preserve it in the moisture down her in Fla. I thought the stabilising effect of the dip would be worth while.
I will run under a light load for a while to warm the windings up and dry them. I will use my megger on them and report. Tho the megger is not an $800 fluke. they are proud of their stuff too!
Dennis

[Doug]

I don't have an $800 meter lol, mines a Cheap $20 Canadian tire special made in China....

Don't waste money on expensive test equipment, odds are any problems you have will be easily found with a cheap multi meter.

At work I do have expensive test equipent but thats because most of the equiment I work on is 600 v. Sometimes I need a scope to check electronics, a maudie walk to check for live circuts in high voltage switch gear or a 1000 volt meggar to check a splice but most often a wiggy or a pocket potential tester are my first choice tools.

Keep it simple, this is only 120/240 use tools accordingly.

Doug