Search found 44 matches

by armscor 1
Wed Jun 12, 2019 1:10 am
Forum: General Discussion
Topic: Large motors and soft start
Replies: 30
Views: 862

Re: Large motors and soft start

Hi Harold, wish my Partner would mow the lawn!! Concur with John, you have a Delta/Delta motor wired for low voltage, Star Delta starting is out of the question. From the photo I have taken of my milling machine motor it is similar to yours, all my motors in the shop are configured this way, 220 VAC...
by armscor 1
Mon Jun 10, 2019 8:03 am
Forum: General Discussion
Topic: Large motors and soft start
Replies: 30
Views: 862

Re: Large motors and soft start

Hi Harold, It is absolutely imperative to know what type of motor you have. 1, Does it have 6 terminals? 2, Is it configured for Star or Delta? Easy way to check is to isolate supply and remove terminal box cover, if 6 terminals and you have 2 links in series it is a Star connected motor and Star/De...
by armscor 1
Mon Jun 10, 2019 12:48 am
Forum: General Discussion
Topic: Large motors and soft start
Replies: 30
Views: 862

Re: Large motors and soft start

Worked in an oil refinery where we had a GEC Alstolm 10 Mega Watt motor, 11KV, about 13000 HP driving a Sulzer axial blower supply air to our Cat Cracker, the beast was Direct on Line and we had to contact electric utility provider before starting so they were prepared for the sudden load change. I ...
by armscor 1
Sun Jun 09, 2019 2:26 am
Forum: General Discussion
Topic: Large motors and soft start
Replies: 30
Views: 862

Re: Large motors and soft start

Dol simply means there is one contactor, three sets of contacts, one for each phase which close when pressing start and feed directly to the motor windings, brutal considering an electric motor needs at least 5 times the full load capacity amperage on the nameplate of the motor. If you look inside y...
by armscor 1
Sat Jun 08, 2019 5:22 pm
Forum: Lathes
Topic: Spindle bearing replacement
Replies: 31
Views: 970

Re: Spindle bearing replacement

Recently replaced my spindle bearings on my 9" lathe. Converted them from ACR ball bearings to tapered roller bearings, used bog standard garden variety Koyo bearings and no measurable runout. I think all the bearings are made on the same machine and are graded to the different tolerances and stampe...
by armscor 1
Sat Jun 08, 2019 5:05 pm
Forum: General Discussion
Topic: Large motors and soft start
Replies: 30
Views: 862

Re: Large motors and soft start

Hi Harold, I assume the motor is DOL, Direct On Line? If the motor has 6 terminals the cheapest option is to install a Star Delta starter and reduce your starting current by root 3. 1492 Amps divided by root 3 equates to 861 amps, almost half the starting current. A much cheaper option than a soft s...
by armscor 1
Tue Jun 04, 2019 5:10 pm
Forum: Lathes
Topic: Spindle bearing replacement
Replies: 31
Views: 970

Re: Spindle bearing replacement

Need what Colchester calls a Talyrond, measures out of round to a millionth of an inch.
by armscor 1
Sun Jun 02, 2019 7:05 pm
Forum: Lathes
Topic: Spindle bearing replacement
Replies: 31
Views: 970

Re: Spindle bearing replacement

Test cut 6061 aluminium at 900 rpm, measured out of round 0.00005 thou on my 12" lathe, good enough for what I do.
by armscor 1
Sun Jun 02, 2019 5:38 pm
Forum: Lathes
Topic: Spindle bearing replacement
Replies: 31
Views: 970

Re: Spindle bearing replacement

Watched a video on YouTube, The World Turns on Colchester Lathes, shows the precision that goes into making the Gamet spindle bearings and the tight tolerances on spindle runout. Going to check my lathes to see how much out of round I have on test pieces. I gave my Emco V10 to my brother, spindle be...
by armscor 1
Sun May 26, 2019 4:54 pm
Forum: Lathes
Topic: Damaged chuck - a forensic investigation
Replies: 21
Views: 1076

Re: Damaged chuck - a forensic investigation

My Sibling, 3 year old daughter was playing with my DSG 13x42 lathe levers, switched off of course. Did not notice the next day she had engaged the half nuts and I have a habit of running the carriage all the way to the tailstock end.Started motor and engaged clutch, horrible crunching sound as carr...
by armscor 1
Thu May 16, 2019 11:28 pm
Forum: General Discussion
Topic: Making a milling machine riser
Replies: 24
Views: 1828

Re: Making a milling machine riser

Good job Mate.
by armscor 1
Wed May 01, 2019 6:41 pm
Forum: General Discussion
Topic: Shopmade Slotting Attachement
Replies: 4
Views: 667

Re: Shopmade Slotting Attachement

Hi Guys, just cut 1/4" keyway in aluminium bronze, plunged in with 1/8" wide hss toolbit and cut out sides to size with ease.
Very Happy.