Colchester Student Mk 1 question

[Chris152]

We're thinking to sell our Myford 7 to get something with a larger swing. I'm currently looking at a Colchester Student Mk 1 and know little about them, other than what I can read or see on the web. Trying to figure out how the controls work, I noticed the one we're thinking of doesn't have lever no. 4 in the pic.

The blurb states:

Does this mean that the one we're looking at does not have a reverse function at all? And if it's not 3-phase AC, does that make it 240 single phase, or are there other options?

The ad we're looking at has not details, so I want to be as clear as possible before we go to look at it.

Thanks for any advice,

Chris

 

[minimutly]

The reversing switch is used on the 3 phase machines. Single phase motors need a changeover switch. On my Single Phase Triumph the switch has been converted to a light switch.
Re the Student, they are a simple, capable, easy to use lathe, much loved, but allways seem to be pricey. There are cheaper priced lathes out there - a similar sized Harrison should be cheaper.

 

[Screwdriver]

Just to help add to the confusion, I went from a Myford to a Colchester Student and mine is 240v with a reversing "switch".

HTH.

 

[minimutly]

How does it reverse the start windings? Does it use a contactor with 4 poles? Does this need 4 poles - I don't remember?

 

[hermetic]

Does it have a hole where the lever was, or is no hole there? the single phase model was usually fitted with a clutch so that the motor was started without having to turn the machine. On the three phase model, like mine, when you lift the control it pulls in a contactor which starts the motor, on the single phase(from factory)machine, the same lever operates the clutch and the motor runs all the time, on the three phase machine, the start/stop lever switches the motor on and off. poor starting torque on single phase motors would soon damage the motor if it had to constantly start agains the resistance of the geared headstock.
Phil

 

[skotl]

Remember, too, that the motor it comes with or not having 3 phase in the workshop needn't be a barrier. A new, reversible, 230V 3 phase motor and a VFD can be had for £200.

 

[minimutly]

Remember, too, that the motor it comes with or not having 3 phase in the workshop needn't be a barrier. A new, reversible, 230V 3 phase motor and a VFD can be had for £200.

Aand also, a reversing motor is a boon if thread cutting in metric. Not sure you'll get a drive and a motor for £200 though?

 

[Chris152]

Thanks all. I've had a brief look into changover switches - is that the same as a drummond switch on the myford? I see there are guides on how to fit them on the net.
We fitted 3-phase with vfd on the Myford, which runs really nicely so I'd be happy to do that again, tho I'd agree it'll cost more than a couple of hundred.
I'm pretty sure it never had a reverse switch on the Colchester, so will assume single phase for now - is the lever marked '1' in the photo above (hard to see, it's white) then the clutch? (I think you've written that Hermetic, just checking.)

 

[skotl]

...Not sure you'll get a drive and a motor for £200 though?

Hmmm.... not too far off. This is a quid more expensive than when I last bought one on 2021, at £163, and then a VFD for £60 from Amazon.

So £225ish

 

[Chris152]

Hmmm.... not too far off. This is a quid more expensive than when I last bought one on 2021, at £163, and then a VFD for £60 from Amazon.

So £225ish

Yep, fair enough :-) I was thinking 4 pole, just because that's what we used before. What is the maximum speed a Mark 1 could handle comfortably? I guess it's dependent on the bearings?

 

[Wedg1e]

I think my Mk2 topped out somewhere around 1200rpm.
From memory, expect second from top to be noisy, they all do that sir.
Should never have sold mine but you know, life's a funny thing

 

[Chris152]

According to lathes.co.uk

'Machines produced immediately prior to the 1950s Student and Master usually had a rather slow range, from 20 to 550 r.p.m., with the new models much faster at 52 to 1000 r.p.m. and later further improved to 54 -1200 r.p.m., both with eight speeds. Two-speed motors were a costly and hence infrequently fitted option, but gave sixteen speeds from 34 to 1500 rpm or even, on some very rare, special-order models, 17 to 750 rpm.'

So I'm assuming the one we're looking at will run at up to 1000/ 1200, but I wonder what maximum speed the spindle could run at comfortably with a VFD fitted. Maybe 1500 (which would be plenty for us)?

 

[indy4x]

Rarely use more than 800rpm on my M300, just saying

 

[Pete.]

According to lathes.co.uk

'Machines produced immediately prior to the 1950s Student and Master usually had a rather slow range, from 20 to 550 r.p.m., with the new models much faster at 52 to 1000 r.p.m. and later further improved to 54 -1200 r.p.m., both with eight speeds. Two-speed motors were a costly and hence infrequently fitted option, but gave sixteen speeds from 34 to 1500 rpm or even, on some very rare, special-order models, 17 to 750 rpm.'

So I'm assuming the one we're looking at will run at up to 1000/ 1200, but I wonder what maximum speed the spindle could run at comfortably with a VFD fitted. Maybe 1500 (which would be plenty for us)?

I would have no issues at all running a bearing headstock up past 1500 on a Student-sized lathe. My Monarch is a 2500 RPM version and they did them to 4000, though is is lighter than the student it's not that much.

 

[hermetic]

yes, lever one is the start stop/brake on the 3 phase model, and the clutch on the factory single phase model.
Phil