Graduate Bowl Lathe

[kenwoodmale]

I have a Graduate bowl turning lathe I hate to see the lathe gathering dust and rust. I'm not greedy and aware that the DOL starter is not working so the lathe currently doesn't run so advice on what to do would be gratefully received.

 

[katellwood]

Mend it!!!

http://www.toolstation.com/shop/DOL+Starter/p95364

 

[kenwoodmale]

Thank you for that information, I have looked for a new starter but been told the 27ADS1X is discontinued. I'm not an electrician but I'll see how I get on.

 

[graduate_owner]

Hi,
what's your intention here? Do you want to sell the lathe as it is, get it running then sell, or get it running and use it?
A few months ago I bought a graduate bowl lathe (hence my forum name!!) for £150. It was running, 240v motor but incomplete, having had a disk sander fitted but no turning bits - rests, small faceplates etc. It only has a rest support on the outside, no inside bits at all.

It was advertised on ebay for about £20, with no bids, then re-listed, so I guess this is the sort of price range you'd be looking at.

Hope this is of some help

K

 

[graduate_owner]

Spot the typo

it was advertised for £200 originally, not £20 (20? wouldn't that be nice)

K

 

[kenwoodmale]

Hi K the intention is to get it running and sell. I did many years ago think I'd further my meager skills but other considerations now prevent this. If I purchase the DOL Starter 240V 4KW with overload protection would I be ok?

 

[dickm]

4kW??? that sounds like one heck of a motor.

 

[graduate_owner]

Hi again kenwoodmale,
The Graduates were originally fitted with 3/4 HP motors (I believe). I have heard of people finding this a bit under-powered, and upgrading to 1HP or even 1 1/2. As far as 4kW is concerned, I think you are way out, for the following reasons:-

1. 4kW is just over 5.3 HP which is way over-powered (I would suggest dangerously so, in the event of a dig-in) for an application of this type.
2. the maximum power you'd normally get on a single phase (i.e. 240v) supply is 3 HP or 2.2 kW, and people often find they need a separately wired supply as the starting current can blow the 13A fuse you find in 3-pin plugs. I have a 3HP motor on my air compressor and I didn't even bother trying to connect via a 3 pin plug, I went straight for a 16A plug and socket (The round, blue type).
3. the push-button starter for the Graduate is probably designed to match the motor and is very unlikely to handle the starting current of a 4kW motor. It may well cause excessive sparking, over-heating and premature failure.
4. I doubt you'd actually find a 240 volt 4kW motor anyway, for reason 2 above .

Lots of reasons then, to go for an appropriately-sized motor. My own Graduate motor is 3/4 HP single phase. I can slow it down with heavy cuts (and I'm not into BIG bowls yet, being a relative beginner) so I would be quite happy to upgrade to a bigger motor. In fact my plan is to change to a 3-phase 3/4 HP motor (courtesy of one of our forum members) which should deliver a bit more punch and give me the advantage of variable speed. (My Myford was supplied with 1/2HP 3 phase or 3/4 HP single phase).

As I said, I'm a relative beginner and there are experienced members on this forum who can give expert advice on turning, but I'm fairly confident regarding my comments on your motor requirements.

Hope this helps, and good luck with your refurbishment.

K

 

[kenwoodmale]

Thank you all for your prompt replies its heartening to know there are people out there willing to give advice freely. i can now see there's a connection between the starter and the motor size. I can't turn the lathe on its side as I'm not strong enough to place it there nor put it back. The door to the pulley does not allow visuals to the motor but I feel it was a 3/4 HP single phase motor that was installed. I shall get the DOL Starter 240V 3KW mentioned by K, it seems to be the starting DOL, e.g nothing lower. Any thoughts on a thermal overload relay?
Many thanks

 

[graduate_owner]

Hi again, kenwoodmale,

I'm a bit confused now - you say you think the motor is 3/4 HP. Where did the idea of 4kW come from? Also, I didn't actually mention a 3kW starter. I said that a 4kW motor would probably cause premature failure to the Graduate starter which is designed to operate a 3/4 HP motor.
Try not to mix up HP and kW. They are both measures of power, but 1HP - 746 watts, or approx 3/4 kW. The maximum size motor you would normally be able to run on domestic 240v mains is 3HP or 2.2kW. The Graduate starter may (or may not - who knows?) handle the starting current of a 3HP motor, but that's irrelevant really as you have a 3/4 HP motor. So go for the 240 volt DOL starter (don't mention 3kW when you search).

I hope this clarifies things.

I agree with you about the motor access, it's really tight. If you should need to get the motor out for any reason, read the following advice which was posted to me by flh801978 in August. I haven't tried it yet, though I soon will - as I said I'm going to upgrade to 3ph.

motor removal is easy just remove the grub screw and lock nut from the pedastal at the end of the motor pivot spindle inboard end...slip the spindle towards the outboard end ( there may be a collar too on the shaft between the motor legs motor then slips out through the door

If you're doing any electrical testing on the motor, be aware that there are (or should be - well there are on mine anyway) microswitch interlocks on the motor access door and on the top pulley cover for safety. If you are going to install a new starter then these microswitches should be connected so as to cut the supply to the starter, i.e. it's supply to microswitch 1, to microswitch 2, to starter all connected in series. Then all 3 (m/sw 1, m/sw2 and starter) must be closed for the supply to reach the motor, and opening any 1 of the 3 will break the circuit and de-energise the starter mechanism thus cutting the feed to the motor. If in doubt, do get a sparky to connect it for you - you don't want to be responsible (either legally or morally) for any injury to the person who eventually buys it from you.

I hope this helps, and if there's anything else you need to know, ask away.

K

 

[kenwoodmale]

Confused, so was I initially the second posting by Katellwood supplied a link to a DOL starter sales page-here supplied- http://www.toolstation.com/shop/DOL+Starter/p95364. I just thought if I got the biggest one that was rated 240V that may do and then asked for advice. On being told the 4KW was massive for the job in hand I went back to the page and the next one, and only one is the 3KW. As the shop is quite close I will go over one day and get the item using your advice. Compared to other sites the starters are quite cheap. On another note do I need the overload protection if I'm not going to use it?

Thank you Dick M for your offer of a starter but I think I'll go for a new one.
J

 

[graduate_owner]

hi again kenwoodmale
if you can get a 3kW starter at a reasonable price then go ahead, you won't have any problems by buying oversized (within reason). I just meant there's no point in buying a bigger unit than you need as it would normally be more expensive. Overload protection is built into some starter units, but are obviously dearer than the basic starter unit. Do you need it? Well my Graduate only has the basic starter (I think - it doesn't look like overload protection), so I'll leave that bit up to you.

K

 

[kenwoodmale]

Now I do feel confident in what I'm doing, so far. I'll let you know if it turns out as expected.
Regards
J