04-09-2013, 12:46 PM
So tootling along all nice and steady today, made 4 stainless seal track sleeves, sleeved an electric motor housing and built up the end of a worn rotor where a gear fits.
Then it all kicks off.
Bane of my life these.
Bridgeport varispeed motor rotor, they wear where the sheaves fit. I reckon I do about 15 / 16 a year and that's from just local repairers. So bung in the lathe and skim down undersize and build up with weld. You need to go under size because you want the weld transition point to be under the surface.
If you don't do this chances are you will get flaky patches on the joint line.
Straight off the welding bench, in fact it's still glowing a bit, don't worry about distortion, whatever you do it will distort so don't worry
just rectify it later.
Support on a steady, rough down to a couple of mm oversize then bung outside to cool naturally.
Whilst the weld was drying this gig rotor arrived, simple job, spun the nose bearing and it's had to be cut off and damaged the shaft.
Easy these are, make a sleeve just a bit bigger than the bearing and big enough to go over the output diameter, turn undersize loctite and bang the sleeve on with a BFH then turn to size.
This is where it went pear shaped, bunged the revolting centre in and the rotor is running off centre ??, so pick up with a big steady on the seal track which isn't damaged, rotor runs true but shaft is running out, seems something has bent this.
Ring company and tell them, they say do it and can we have it back for 10:00am tomorrow.
So skim under size all over as the lot needs doing.
Drop onto purpose made barrow for carrying rotors, a sack truck is no good as with a long rotor you can't get thru doors and up gangways. This one was made from a propane bottle. the two brackets clip on the edges and have two bearings fitted, a very crude steady that lets the rotor rotate so you can weld round a journal.
Welding done, got to wait for this to dry.
So get the bridgy rotor back and do the final diameters.
So all finished except the keyway, circlip groove and the roll pin hole.
The big rotor will have to wait until tomorrow, off to the pub for a pie and a pint, bastard of a job but someone has to do it.
Problem tomorrow is can't use the centre in the end as it's bound to be out, no steadies I have for this lathe will run on the bit of shaft not welded and can't guarantee that it's true enough anyway.
Watch this space.
Then it all kicks off.
Bane of my life these.
Bridgeport varispeed motor rotor, they wear where the sheaves fit. I reckon I do about 15 / 16 a year and that's from just local repairers. So bung in the lathe and skim down undersize and build up with weld. You need to go under size because you want the weld transition point to be under the surface.
If you don't do this chances are you will get flaky patches on the joint line.
Straight off the welding bench, in fact it's still glowing a bit, don't worry about distortion, whatever you do it will distort so don't worry
just rectify it later.Support on a steady, rough down to a couple of mm oversize then bung outside to cool naturally.
Whilst the weld was drying this gig rotor arrived, simple job, spun the nose bearing and it's had to be cut off and damaged the shaft.
Easy these are, make a sleeve just a bit bigger than the bearing and big enough to go over the output diameter, turn undersize loctite and bang the sleeve on with a BFH then turn to size.
This is where it went pear shaped, bunged the revolting centre in and the rotor is running off centre ??, so pick up with a big steady on the seal track which isn't damaged, rotor runs true but shaft is running out, seems something has bent this.
Ring company and tell them, they say do it and can we have it back for 10:00am tomorrow.
So skim under size all over as the lot needs doing.
Drop onto purpose made barrow for carrying rotors, a sack truck is no good as with a long rotor you can't get thru doors and up gangways. This one was made from a propane bottle. the two brackets clip on the edges and have two bearings fitted, a very crude steady that lets the rotor rotate so you can weld round a journal.
Welding done, got to wait for this to dry.
So get the bridgy rotor back and do the final diameters.
So all finished except the keyway, circlip groove and the roll pin hole.
The big rotor will have to wait until tomorrow, off to the pub for a pie and a pint, bastard of a job but someone has to do it.
Problem tomorrow is can't use the centre in the end as it's bound to be out, no steadies I have for this lathe will run on the bit of shaft not welded and can't guarantee that it's true enough anyway.
Watch this space.
John S., Nottingham, England.
![[Image: Blidgeport.jpg]](http://www.stevenson-engineers.co.uk/files/Blidgeport.jpg)
