Hlvh tailstock condition of bed mating surface?

sam_stlouis · May 30, 2018

Doing maintence on my hlvh I've had it a little while but am just now getting it going. Moving the tailstock today and a white strip starts coming out from under it. So I took it off to look under it. It had several white strips of material. Half are missing. And what looks like someone took a engraver and randomly etched the base, it is smooth no raised surfaces. I'm thinking the engraving was to give the strips something to cling to. I know the base had a nylon type material originally. Are these white strips the original material, and if so where can I buy some. I can't find any pictures of the bottom side of an hlvh tailstock, is this how they normally look, or did someone try to do some kind of repair. Thanks for any help

I guess I will have to upload pic when I get home does not want to seem to upload on my phone

rons · May 31, 2018

The etching on the base and the white strips are not original.

What is the thickness of the white strips on the bottom of the tailstock? Is that an attempt to raise the height of the tailstock? Slide the tailstock over to the head and see how the height of the spindle nose compares to the tailstock height. One way to do this is put a point into a collet and mount into spindle. Put a decent center into the tailstock. Then get a bar of aluminium about 6" long with a center drilled hole in each end. Mount the bar from spindle nose point and tailstock center. Mount a indicator on the tool post or carriage and go back and forth over the aluminium bar. What deviation do you measure.

You can machine your aluminium test bar without the tailstock.

sam_stlouis · May 31, 2018

Here is a pic, it had several strips. I can see where they were but half are gone now. I read that they had a nylon or Teflon material .010 originally on certain model years, so I was hoping maybe this was it.

rons · May 31, 2018

I am not surprised. The tailstock has a lot of contact area making sideways movement difficult. I always smear a bit of oil on the bed before any movement. Where did you read about this teflon (.010) being original? I would think a single sheet of material would be better. A single piece of Turcite glued and scraped.

Your picture does not look like that was done at the factory.

sam_stlouis · May 31, 2018

I have no idea if what mine has is the original Teflon or not. And I don't know the thickness of the material mine has either but will measure Tommorrow, I will also try to do the measuring test you suggested.
I read in a post from Richard King, that at some point they added Teflon/nylon material to the base of the tailstock, he mentioned it was around .010 thick. And found a few other mentions of it on the Internet when searching. I could not find any pics, was hoping someone had a model with it to compare. What mine has looks kinda sketchy, I agree with you in that I would expected a full sheet, I'm assuming what I have is not original, but would like to know for sure

rons · May 31, 2018

Get the serial number off the right side of the bed. Then lookup the model year. Will be helpful when discussing the machine.

In my opinion it is better to wipe the bed (flat and sides) with a clean towel dipped in #4 oil.

1. Cleans the bed.
2. Makes it easier to slide the tailstock.
3. Prevents small metal particles from scratching the surfaces.

Would not go out of my way to do this Teflon modification just because the tailstock is heavy.

Send a private message to Richard King and mention your serial number.

FredC · May 31, 2018

I agree with earlier comments that the plastic strips in your machine are not original, it just does not look like Hardinge work. I can not say that Hardinge never used or experimented with Turcite on the tailstock, as I not studied the history of this lathe. Maybe Larry would know? Mine has a flaked cast iron surface. As far as friction goes I think they should have had an oil port going to the center of the tail stock flat surface. On my machine, I can clean the bed thoroughly and lift and slide the tailstock onto a puddle of Vactra on the bed. After that I will have to be careful that the tailstock does not slide off the bed as it is not perfectly level.
The solution to the OP's problem may be find what thickness shim will bring the tailstock to level and centered, then find a plastic sheet that same thickness that can be glued to the bottom?

sam_stlouis · May 31, 2018

so I confirmed as already suggested that this was not original. After removing it all you can see an oil port has been added. The shim material measured .007 to .0075 not sure how much the adhesive added to that. Going to clean off all residue then measure tailstock height to compare to spindle. And reshim as needed.
I guess the easiest thing would be to reapply plastic shim. Scraping is not something I know how to do. So would rather not use something that requires scraping. Any suggestions

sam_stlouis · Jun 3, 2018

Thanks, wish mine looked like yours. Yes with further digging I found what you said, there was none on the tailstock. Somewhere in my research I confused a statement that made me think the tailstock had some. I think on the tailstock the important thing is that it is the correct height and repeatable, so I think reapplying plastic shim, no scraping would be fine.

Demon69 · Jun 3, 2018

I dont know anything about that particular lathe and how it was orginally, but if you use a 'way liner' it should be scraped to fit. Really its not such a big deal. Have a quick look over at the scraping forum for the jist, it likely wont take much at all.
If it was me id probably ignore the thickness of the material thats there, you dont know how worn it is. turn a spud same diamter as the tailstock quill and incatate the tailstock to see how low it is. Wind out the tailstock quill to see where its pointing. Figure the thickness of material you need and go a little thicker. Glue it up and scrape it in, doesnt have to be a work art to work well, aim to have it a couple thou high so itll wear in before it wears out.
Cheers
D

rons · Jun 3, 2018

sam_stlouis said:
Thanks, wish mine looked like yours. Yes with further digging I found what you said, there was none on the tailstock. Somewhere in my research I confused a statement that made me think the tailstock had some. I think on the tailstock the important thing is that it is the correct height and repeatable, so I think reapplying plastic shim, no scraping would be fine.

Why not figure out why the shim material was put there in the first place to raise the height by .007".

Was the bed planed down?

A rebuild shop owner talked to me about planing my bed down. I asked him if they would shim the bed or tail stock from underneath. He said that was BS. He would remove the head and scrape it down to fit the bed. His words not mine. After that I just let it go.

Search

Largest Manufacturing Technology Community on the Web

Search

Hlvh tailstock condition of bed mating surface?

sam_stlouis

Cast Iron

rons

Diamond

sam_stlouis

Cast Iron

rons

Diamond

sam_stlouis

Cast Iron

rons

Diamond

FredC

Diamond

sam_stlouis

Cast Iron

sam_stlouis

Cast Iron

Demon69

Titanium

rons

Diamond

Similar threads