newbie headstock question

Hey everyone I have a question for you all about my headstock(lodge and shipley). I just repaired the direct drive on the headstock and all seemed to be fine with that. Now after trying to use my 1.5 hp compressor motor it doesn't seem to want to turn. Mind you it has always been tough to turn the headstock. So I guess what I am trying to ask is how easy should the headstock turn? I looked through all the catalogs and books and can't find any reference to how easy this should be. Thank you for all your help.

Should turn with no effort at all. You may recall my saying keep exact track of any shims when removing bearing caps. If there were no shims there clearly needs to be. The spindle MUST have some clearance between itself and the material the bearings are made out of for an oil film.

If you are just installing the bearing caps and tightening the bolts, you need to start over and place, say, .0015 (one and a half thousandths) shims between the cap and the headstock and see if that did any good.

We won't get into scraping bearings to fit spindle just yet, but you may need to tackle that eventually depending on what sort of abuse the lathe has seen in the last 108 years.

Basic requirements:

Quality finish and geometry of spindle journals (round, concentric, no taper)
Exact fit including side to side and up and down alignment with ways
Proper clearance for oil film (around .0005" or half thousandth as a target on diameter on this small machine)
No effort to turn spindle with oil in place and cap bolts torqued.

These very nice fits for plain spindle bearings is the reason for a light spindle oil such as Exxon Mobil Velocite #10.

John Oder

I don't think it is a clearance because I kept track of all the shims and put them back where they were. It is even hard to turn with all the bolts loose. I had cleaned the bearings so I know there is not dirt or debris that is jamming it up against the bearing. Am I over looking something obvious?

Things you could check:

Thrust washers back of cone and ring nut on end of spindle set end play. If you have ring nut too snug, spindle will be draggy.

This is tricky!

The reason is there is the spindle gear that drives the feed train also in the stack up.

If the gear is a nice snug fit on the spindle it WILL NOT slack off if you back off on the ring nut in an attempt to free up thrust or end play setting.

You have to not only back off on ring nut, you have to bop the spindle forward thru the gear with something heavy but non marring (I like my 4 lb rubber faced truck tire hammer)

Then you can sneak up on a freer end play setting.

John Oder

John, your advice worked. It now moves much more freely. That is when the bearing near the spur gear isn't tightened down. Now there is a shoulder on the bearing with about .07" space (give or take as I can't really measure it that well), I am thinking that is where I should shim it so that it isn't so tight as to lock the cone pulley.

Now I have never shimmed a lathe before, is there a specific procedure I should follow? Also do you recommend brass or paper for the shim stock? Thanks for all the help

~John

My ATw has card board shims in it, Had to remove some to tighten it up a little.

You could move the spindle up and down prying with a short 2 x 4, I took 1 shim out and it works great now.

Paul

I have never shimmed a lathe before, is there a specific procedure I should follow?

Click to expand...

Yes, you put in a shim of any material you think will last and is available down to a thousandth thick. If what you put in is too thick or thin, try again.

We after after results that satisfy the situation at hand.

John Oder