Couple of Lathe Questions

[Gerold Griffin]

Hi All:
Been looking a lathes with a sliding headstock lately and it seems like every one has the motor on the outside of the headstock. It seems to me that if the motor was inside the headstock it would make belt changes a snap and offer more protection to the motor itself. According to a Leeson rep it would not hurt the motor since it would be running in the oppisite direction as long as it was made to run forward and reverse. (hooked up to a VFD) So my first question is "Am I missing something here?" Would there be a sufficient heat build up to damage the motor or what?
My last question is in reqards to the gap between the ways. Is there an industry standard measurement for this? I am not talking about small lathes here but rather like a Robust or Oneway 24/36.
You may have guessed that I am thinking about building a lathe and you would be correct. Hopefully I can start a wood mock up of it after the first of the year. Sort of a Robust/Stubby/Oneway/Myway combination with a Serious attitude thing. Not sure I can do it in wood never mind steel but thinking real hard about giving it a go.
Thanks

[curtis rosche]

if the headstock goes down to the end of the bed there is no reason to need the motor inside. there are no moving things on that side of the headstock.

where are you located?

[Dennis Ford]

I think the motors are outside the headstock due to space issues more than anything else. I don't believe there is a "standard" as to the gap between the ways. Building a lathe is a great experience, they are simple machines but designing a good one that you can build with limited tooling is challenging.

[Gerold Griffin]

Dennis, already made contact with a machine shop just up the road that can handle everything I can't.
Curtis, the reason I want that motor inside the headstock is to protect it. It is my unfortunate experience that when the shop roof comes off and the roll up door gives way and travels 40 feet, well whatever it hits on its merry way is toast!! Just trying to salvage a motor.

[curtis rosche]

are you making a bowl lathe or a spindle lathe?
for a spindle lathe, you could make it similar to the plans i posted a while ago, but make the bed slide , instead of the head stock sliding. less chance of vibration...

[Gerold Griffin]

Curtis it would be along the lines of a Robust or Oneway. Yes it would have a tailstock so you could do spindles but large enough to do bowls. Also, by puttting the motor on the inside, with my design it should be alot easier to change the belt o the pulleys.

[Paul Atkins]

Seems like you'd have to have a small motor or a large headstock to put the motor inside, unless I'm missing something. If your roof comes off etc., I think the motor on the lathe is the least of your problems.

[Jeff Nicol]

Gerold, I have the PM3520b and if the motor was put inside the housing the case for it would have to be huge!!! They designed it very nicely and it is so easy to chage the belts on it that I really don't know what you are getting at. THe TEFC motors are built tough and for rugged use and have a heavy metal case. Are you going to make it a sliding headstock? By saying you want it like the Robust or Oneway the motor is inside the base with a longer belt going to the pulleys. If you plan on doing outboard turning and inboard you won't need to slide the headstock. Like has already been said the headstock on the 3520 and the jet 16-42 slide all the way to the end so you can turn larger than the swing over the ways. The ways can be whatever you choose if you are making it yourself. The PM's ways are 2.5" apart and about 8" wide at the widest. If you plan on buying the banjo then get the one you want and build the lathe around it. There are just to many variables to take into account to make reccomondations right now. So I guess I would get a bed designed and made then the headstock made to your likeing. If the headstock is to be solidly located then you can figure out your motor configuration. I could ramble on for a long time as ideas and images flow into my head as I write this so I will end it here!

Good luck,

Jeff

[curtis rosche]

you should think about making it so that the headstock would be stationary i.e. bolted to the floor maybe, and then the bed would slide back and forth through the headstock, just a thought.

[Gerold Griffin]

Yes the headstock would have to be bigger than normal therefore heavier. But that aside is there any other reason why it should not be done?

[Dave Ogren]

Gerold,

Motor inside the headstock, bolted to the floor, now it sounds as if we are talking about a VB 36 clone. In my opinion that is the way to go. If you have any questions about them I would be happy to answer them for you,
I don't have a bed or a tail stock, but I only turn bowls.
Best of luck on whatever direction you go.

Dave