Harrison L5A feed nuts

[AndyStobbs]

I found a website around the time I bought my lathe that had replacement nuts available for the slides on my lathe. I cannot find that website again, can anyone point me to it?

Thanks

 

[Pete.]

I'd be looking at making an acetal nut, don't need to do any threading then.

http://bbs.homeshopmachinist.net/threads/43645-Making-Acetal-leadscrew-nuts-the-easy-way

 

[AndyStobbs]

They did exist though. They were listed on this site. Made in phosphor bronze, this was only a few months ago.

 

[nickk]

hpc components .

 

[Shox Dr]

I'd be looking at making an acetal nut, don't need to do any threading then.

http://bbs.homeshopmachinist.net/threads/43645-Making-Acetal-leadscrew-nuts-the-easy-way

I re-reading that thread the other day, I take it you are self and the same

 

[Pete.]

Nooooo, I contributed in that thread but the guy who started it is Evan Williams, a very clever dude, great home machinist/engineer and fine astrophotographer. He's built a home-made telescope and used it to produce some fantastic images of galaxies, start clusters etc.

Evan's website: http://ixian.ca/gallery/index.php

 

[Shox Dr]

Yup, that's what I meant

 

[zzr1200]

Scroll down to:

HARRISON L5, L5A, 11-inch and 140 Lathes:



New cross feeds nuts in bronze: £75New top slide nuts in bronze: £55

@

http://www.lathes.co.uk/page8.html


hth

zzr

 

[Stueeee]

This bloke makes parts for any lathe, http://www.latheparts.co.uk/ may be worth a call.

 

[AndyStobbs]

That it thanks guys. £130 isn't too bad given they will outlast the lathe. I can't see the acetal lasting as long.

 

[Shox Dr]

Did you read the thread or have you used Acetal?

 

[brightspark]

take a gander here http://plastics.ides.com/generics/2/acetal-acetal

 

[AndyStobbs]

Read the first page. Did notice it was a long thread. Not used acetal. I'm probably way off the reality of the fact. Just doesn't seem right to use plastic to do a metal's job.

 

[brightspark]

Read the first page. Did notice it was a long thread. Not used acetal. I'm probably way off the reality of the fact. Just doesn't seem right to use plastic to do a metal's job.

i must admit i prefer the traditional materials myself as they stand the test of time but technology moves on . some for the better some for worse

 

[Pete.]

Acetal is an engineering plastic and supremely suitable for making lead screw nuts. It's impervious to most oils and chemicals, doesn't absorb moisture and has a low co-eficient of friction compared to brass and very low wear. When it does wear, it won't wear out the lead screw which should now last for ever. If you don't think it's man enough go fetch the jack out of your car. Chances are it has an acetal nut.

 

[AndyStobbs]

Holy thread revival batman...

I got around to mounting the milling table on my lathe yesterday, and have encountered two problems.
The table was sold as being suitable for a l5a, such as mine, and included a cross feed nut but was missing the taper gib strip, I hoped to use my own gib strip from the cross slide.

First I've discovered that the cross feed nut will not fit my feedscrew despite being outwardly identical to my original nut. The thread isn't right, did Harrison change the thread over the years?

Secondly the milling table is not designed to use a taper gib strip, but an adjustable flat strip. As a result the taper gib doesn't fit and the tapped hole for setting it is missing.
Also the milling table doesn't look like the one in pictures on lathes.co.uk - mine having 4 t slots, not 5.

It does sit on the carriage correctly, and traverses nicely when my original nut is fitted to it, but I will have to make a gib strip.

So does anyone know what this milling table might be from, and what the hec is the feed nut designed to be used on, the 140 maybe?

 

[Keith 66]

I was the bloke that sold it to you, it definately came off a Harrison 140 of about 1971 vintage. I had been told that it was identical to those off the L5A. Two years ago i acquired 3 Harrison 140's and all had milling tables, two i sold separately.
I wonder if the nut being different is the difference between a metric & imperial dialed machine? The earlier L5 is far more likely to be imperial but the 140's were often supplied in metric guise.

 

[Pete.]

I wonder if the nut being different is the difference between a metric & imperial dialed machine? The earlier L5 is far more likely to be imperial but the 140's were often supplied in metric guise.

I'd say it's probably a sound bet.

 

[AndyStobbs]

Yes I remember but didn't want to name names as it isn't a complaint, merely an observation.

Hmmm so a 140 feed screw would be halfway toward a metric set up on my l5a then...

 

[Keith 66]

Then you would have to find a new leadscrew, gearbox would be different etc etc, sounds like a lot of aggravation! Harrison owners group on yahoo might know more they seem to have a world of info on these.