Thread: Help Installing lathe spindle

I Have been playing with my hafco 960 lathe. I have removed the spindle and installed the new bearings But trying to install the spindle in the.headstock has got.me.beat. As the drive gears are a light press fit on.the spindle I tried cooling.the spindle in the freezer and heating.the gear and it has gone on about a third of the way but it wont buge. Taking the spindle out with the deadblow hammer was the easy part

Can you pack the spindle in Dry Ice?

Michael

I could try the dry ice if I had some I may have to have a crack at making some. Its a harder job than I thought

1.find an old pot big enough to hold all the gears.2.fill with oil maybe engine or hydraulic oil.#.Put in your gears and heat up the gears and oil.4Heat carefully until the gears are too hot to handle with bare hands xxxxx caution watch closely to avoid the oil self igniting.5.Find a Fire extinguisher a CO2 larger the better. 6.assemble with gloves all the gears with a wooden dowel feed in from the far left to hold the gears in position.7.When all is ready hit the shaft with the Co2 until it is freezing with gloves to avoid burns from cold push your shaft in firmly in 1 steady push.If you are game you can use LPG straight out of cylinder it can be done but out in open co2 a much safer option. Plumbers use that to freeze gas and water pipes to silver solder but old hat and frowned upon freeon gas too was used but now ozone unfriendly.Give that a shot and be pleased to see if it works Cheers John.6

Originally Posted by j.ashburn

1.find an old pot big enough to hold all the gears.2.fill with oil maybe engine or hydraulic oil.#.Put in your gears and heat up the gears and oil.4Heat carefully until the gears are too hot to handle with bare hands xxxxx caution watch closely to avoid the oil self igniting.5.Find a Fire extinguisher a CO2 larger the better. 6.assemble with gloves all the gears with a wooden dowel feed in from the far left to hold the gears in position.7.When all is ready hit the shaft with the Co2 until it is freezing with gloves to avoid burns from cold push your shaft in firmly in 1 steady push.If you are game you can use LPG straight out of cylinder it can be done but out in open co2 a much safer option. Plumbers use that to freeze gas and water pipes to silver solder but old hat and frowned upon freeon gas too was used but now ozone unfriendly.Give that a shot and be pleased to see if it works Cheers John.6

Find a piece all thread and nuts and washers to cover the spindle nose feed that through and draw in the spindle all the way home tightening nut on far left of hollow spindle.1'' be ok as has a good lead and will move the all thread quickly ie low number tpi. J A.also a piece of pipe bigger dia than the spindle on the end to allow shaft to come trough.

Hi Andre,

This maybe a stupid question so forgive me; Is there a chance that you lucked out and have created a small burr on the shaft when first pushing on the gears?

It seems unlucky that it was easier getting them off than back on. I have replaced the spindle bearings in my lathe and had all the gears out and they too were a very nice snug fit. The slightest hint at mis-alignment from tapping one side more than the other created a siezed gear on the shaft that took a disproportionate amount of force to remove.

Simon

I did stone the shaft and the gears are a nug fit. I may pull it out tomorrow and hit the gears and spindle with fine emery. But when you take it out you have something to push against but not when puting it back in.

Originally Posted by welder

I could try the dry ice if I had some.

BOC sell it (as do other places). You may have to order it in. From memory it gets down to -80C, so gloves are required but at the same time it does shrink things.

Michael

Be very careful if you go down the freezing path.

Consider how many gears you have to get on the spindle and there relationship to any key ways.

Also consider how you will be placing the spindle into your headstock and the amount of room you will have to maouver things.

I would consider the freezing option as a last resort.

As you said remove the spindle and gears,check for any burs on both and trial assemble.

If you needed to knock the spindle off the gears getting it out you may if no burs are found have to knock it back on.

From my experience the gears should be a sliding fit as they go to a shoulder ,I think that one of them is on a bush and also held by a cir-clip.

All of these items going onto your spindle will take a little time and if the spindle was frozen will not take too long to heat it up.

If it was frozen and one of these items jammed it could be extremely hard to remove.

Are you replacing the gaskets at the ends.

Well spindles out again and on.the bench. I have emery the gears and.spindle but I still cant get the gears on time to measure. EDIT okay went and.meaured the gear and the shaft and they are size for size 59.99 mm

Originally Posted by welder

Well spindles out again and on.the bench. I have emery the gears and.spindle but I still cant get the gears on time to measure. EDIT okay went and.meaured the gear and the shaft and they are size for size 59.99 mm

That's a snug fit! Looks like you may need to take advantage of the thermal expansion coefficient after all. Simon

if you cannot get any dry ice, try anti freeze mixed into water
get the mixture so, that it will just freeze
plug up your spindle on one side, doesnt have to be water tight
fill a plastic bag with the mixture and put it in the spindle and put in in the freezer untill the mixture is solid
it will not be colder than just putting the spindle in the freezer but it will stay cold over a much longer time
thereby giving you time to work the spindle through the heated gears without so much time pressure