Quantcast
  • We invite you to join UKWorkshop.
    Members can turn off viewing Ads!

Replacement motor

UKworkshop.co.uk

Help Support UKworkshop.co.uk:

Sawdust

Established Member
Joined
1 Nov 2005
Messages
470
Reaction score
0
Location
East Yorkshire
Hi,

Can anyone point me in the direction of a motor for this:

https://www.ukworkshop.co.uk/forums/view ... hp?t=30174

The one it came with is a 2 pole and much too fast (2800rpm). I can find plenty of 4 pole (1400 rpm) motors (Machine Mart/Axminster..) but they all have shafts which are 40mm long and I need something about 75mm which a 4 step pulley will fit onto.

Many thanks
Mike
 

Bodrighy

Established Member
Joined
6 Jan 2007
Messages
5,818
Reaction score
0
Location
Bromham, Wiltshire
I don't understand the pole stuff but are you saying that the top speed is 2800rpm? If so that's not overly fast. What speeds does it have within the range?

Justs been looking here. You should have a speed range of 425, 790, 1330 and 2250 rpm

Pete
 

Sawdust

Established Member
Joined
1 Nov 2005
Messages
470
Reaction score
0
Location
East Yorkshire
Bodrighy":1g3orva6 said:
I don't understand the pole stuff but are you saying that the top speed is 2800rpm? If so that's not overly fast. What speeds does it have within the range?

Pete
2 pole motors run at 2800rpm and 4 pole at 1400 rpm.

The problem I have is that the lathe is designed for a 1400 rpm motor. The motor has a a 4 speed pulley and the headstock has a matching 4 speed pulley. If I use the motor I have, all the speeds are twice what the should be so I don't have a safe low speed for turning anything large and if I use the top speed I think the whole thing might take off!

Cheers
Mike
 

Bodrighy

Established Member
Joined
6 Jan 2007
Messages
5,818
Reaction score
0
Location
Bromham, Wiltshire
So your lowest speed will be 850 and your top speed 4500 is that what you mean?

Pete

Edit: Just had a look at the motor label on the other one and I see what you mean.
 

Sawdust

Established Member
Joined
1 Nov 2005
Messages
470
Reaction score
0
Location
East Yorkshire
Bodrighy":mc3yykib said:
So yopur lowest speed will be 850 and your top speed 4500 is that what you mean?

Pete
Yes,

I get:
850/1580/2660/4500

and I should have:
425/790/1330/2250

Mike
 

TEP

Established Member
Joined
11 Mar 2007
Messages
1,358
Reaction score
0
Location
Chester
Mornin' Mike.

When I converted to variable speed on one lathe I had the same problem with the 3ph. motor.

My final answer was to have a extension shaft section made up which fitted the existing shaft, and gave me the extra length I needed to fit the pulley.

:idea: See if you can find a local hobby engineer.
 

flh801978

Established Member
Joined
21 Dec 2008
Messages
1,281
Reaction score
19
Location
Sheffield uk
Mike
I have replaced the motors on my 2 graduate lathes both with 3 phase motors under variable speed control.
The length of the shaft was shorter but i havent found a problem with that
you almost certainly have to bore out the original pulley and cut a key way and tap new holding screws..
I increased the size of motor to 1.5 hp ( 2 kw) so the shaft was 24mm
rather than 5/8 " on the original pulley

If you go this route then a motor will cost you £100 ish and an inverter £ 180 ish
Those are for 2 kw less for smaller items

If you need any help pm me ...I have full metalworking shop too for mods

Ian
 

dickm

Established Member
Joined
25 Oct 2004
Messages
4,506
Reaction score
3
Location
North of Aberdeen
TEP":36tsli5l said:
When I converted to variable speed on one lathe I had the same problem with the 3ph. motor.

My final answer was to have a extension shaft section made up which fitted the existing shaft, and gave me the extra length I needed to fit the pulley.
Yes, I've done this for a small Record lathe. The spindle extension needs very careful making, so that it is exactly concentric with the shaft, as otherwise you get horrendous vibration problems. So make sure your friendly engineer is good at precision working :)
Apart from that, it's a pretty easy job, especially with a foot mounted motor like the Jubilee's. Try Gavin Oseman on the homeworkshop site for inverters; he's very helpful and knowledgeable.
 
Top