Harrison Milling Machine

[rleete]

Nice progress on a messy job. Can't wait to see it all cleaned up.

[Zoot Suit]

Thanks for the words of encouragement.

I had been looking for a small mill that was rigid. Lots of small mills are just beefed up pillar drills which is not what I wanted, I am hoping that this one will suit my needs.  According to lathes.co.uk this one weighs 1092 pounds (495kg) although mine will be a bit less without the overarm so hopefully it will be a solid machine.  The table seems to be a good size, approx 2'6" x 8" (750mm x 200mm).  Not huge but big enough for 95% of what I will need to do.

The wires from the cup wheel make you look like a porcupine and yes the few that get through do sting.  PPE required.

The gearbox, as I have said, is similar to the one on my L5 lathe.  I fear that once this machine is done I will have to do my lathe next.  Someone painted the lathe green before I got it so I at least will have to make it grey too.  More looking like a porcupine in store there I fear.  I assume that it was the fashion to paint grey machines green at some point in the past.

Is 2 part urethane paint what I would call 2 pack isocyanate? If so I don’t have an air fed mask so would be hesitant in using it although I do agree that it is the best as far as oil and solvent resistance goes.

A manual is next on my list, I will ask on the Harrison lathe Yahoo group first before I buy one.  Its the small parts that are always the ones that can be a puzzle.

I have been cleaning up the small parts.  Not too many horror stories yet although I have found one bearing that is rusted (one of the ones near the knee handle) and the inner race of the bearing is fixed solidly in place.  I will deal with that once I have finished the cleaning process.

I spoke to a local motor rewind company this morning who were less than helpful.  They said that they couldn’t rewind the motor without the original winding data which they doubted that they could get. 

I then emailed Brook motors who still exist.  They sent a very polite reply that said that this series of motors was discontinued 30 years ago and they didn’t have the data.  They did suggest that I speak to a Brook Crompton Motor Centre (who I assume are Brook Crompton dealers).  I will speak to them tomorrow but I doubt that they will be interested in such a small job.  I am not a motor rewind expert but I an sceptical that someone needs the original data to rewind a motor.  Surely its just some maths? 

The company I work for employ a couple of chartered electrical Engineers so I will ask them what they think.

John

[f350ca]

Urethane paint requires a hardener but is not the same as the two part epoxy paints that have isocyanates. Yes they're nasty to say the least.

[hermetic]

The main motor will not run on single phase, it is dual voltage in that it will run on 240v 3 phase(most of Europe), or 415v 3 phase (UK), and will run on three phase 240 volts from an inverter, as will the feed motor, but you would need an invertor for each motor. You can get 240v single phase to 415v 3 phase inverters, but they are expensive. Don't know if the Brook Gryphon will rewind as single phase, but I am an elec eng, not a rewind expert, so I could be wrong, but ANY local motor rewind shop will be able to tell you, no need to go specially to Brook/Crompton, who are now chinese owned anyway :-( I have the same milling machine, except yours has got the posh clutch on it! I still use the coolant system as installed, and have had no problems with it, or the main motor. Not having an overarm is a pain, but possible to get them, or even fabricate one? The support bearing is missing too I suppose?
Phil

[hermetic]

Look out for an overarm on ebay and the like, or you could even find a vertical head and use it as a vertical mill. I never thought I had a chance of finding one for mine, but I did, and in under 2 years too!

[Zoot Suit]

Re the motors. I am aware of the differing voltages and single vs three phase. My intention is to run the main motor through a phase converter at 230volts three phase as its a dual voltage unit. I want to use a 230 volt three phase motor for the small motor also through a separate phase converter to give the option of varying table feed electrically as well as by change gear. (I thought I had mentioned this previously above). I had assumed that it would be difficult to find a new motor to fit without having to modify the motor or gearbox or build some sort of adapter hence why I am looking at rewind options first. If I cant get it rewound then I have some ideas for a Plan B.

Re the missing overarm I have a plan for that which will be phase two of this project.

Re the 2 part urethane paint. I had a look online and most sites say it also contains isocyanates so an air fed mask is required. I am led to believe that all 2 part paints contain isocyanates. I will have to do some more reading about the paint possibilities.

John

[Zoot Suit]

I spoke to 2 more motor rewind specialists today, ones who say that they do obsolete motors. As I had hoped/expected they just said "no problem". A rewind is more expensive than a new motor but if I bought a new motor it wouldn’t fit straight on so I would need to fabricate some sort of adapting plate or modify the motor so I think its worth the extra cost.

Next I need to look at replacement hand wheels. The one on the right end of the table is just a keyed fit so a new handle (which will come with just a small hole in the centre) will be simple to do. The other one, the one on the knee, is splined. I haven’t made a splined hole before, I think I can mount it on my lathe and, if I can work out how to index it, cut the spline with a form tool in the toolpost. It is a 36 spline fitting, my question is, are splines a standard geometry? I assume that they are. I want to sort the handwheel out before the machine is back together to I can offer the shaft up while the wheel is still mounted in the lathe.

hermetic, can I ask a question. You say that you have a similar machine. What size handle or wheel is on your knee? I want to fit one as big as possible on the knee and before I took the machine apart I estimated that a 12 inch wheel would fit. Does this correlate with your machine, would a bigger one fit?

John

[hermetic]

To raise and lower the knee, mine has a handle, I think about 12" long, but I will get a picture and measure it for you tomorrow. Good news about the motor The feed motor is flange mounted, and would I would have thought, been a standard flange, but again, your motor shop will know better. Just had a look through my pic file, and I don't have a clear one that shows the hande, will take one tomorrow.
Phil

[hermetic]

As far as paint goes, steer clear of two pack, I use either cellulose or synthetic high build primer, followed by synthetic alkyd enamel tractor paint, such as "Tractol" thinned with white spirit, and sprayed. Very oil resistant once cured and high gloss as well.

[Zoot Suit]

Thanks Phil, a picture and dimensions would be great.  Mine came with a hand wheel on the knee, only about 5" in diameter so way too small.  I looked at the picture of a machine on lathes.co.uk and it would seem that the original configuration for the machine was a handle not a wheel.  I will go with a handle as it makes so much more sense than a small wheel especially if there is something heavy on the table and you want to raise it up.

Alkyd enamel was a type of paint on my list of possible paints but I haven't used it before.  Its good to hear about your first hand experience of using it.  I will order some and some primer.  I wouldn't use 2 pack without an air fed mask, my health is too precious.

Thanks again,

John