Harrison L5 lathe

[morrisman]

Hi I'm worried that my 1950's Harrison L5 lathe has been tampered with . Apparently , at the factory in Yorkshire , they spent a lot of time matching the bed to the base of each lathe. Removing the bed from its base is not recommended . I can see a odd shaped bolt on the bed and I feel that the bed has been disturbed at some point in time . The base is a heavy rigid cast and thick steel construction . I cannot see any obvious adjustment points . Would they have used shims under the bed mounts to align the lathe ? I recently fitted a 2hp motor and a VFD . It is a delight to use as it has a clutch/brake but it is rather noisy in top gear , sounds like a jet engine Mike

[Michael G]

My late is similar. At the end of the day they do all that so that it cuts straight and is rigid. If it does that then don't worry.

Michael

[BaronJ]

I agree with Michael,

They are a heavy well constructed lathe. I doubt that a single bolt with an odd shaped head is anything to worry about.

[morrisman]

I am probably worrying too much :;

I will perform a few test cuts as see how accurate it is .

Apparently, these lathes were used by many training institutions in the UK . The controls are simple and easy to use . This example has the small spindle bore which is a pain but the machine has other redeeming features . The later version used the L00 chuck mount .

I believe this lathe was used in a navy ship, as the Harrison L5's are fairly rare in Australia . Maybe one of the ex RN Q class destroyers that were reissued to the RAN

I found this rebuild thread which shows the simple design .

http://www.metalworkingfun.com/showthread.php?tid=788&page=7

[BaronJ]

Hi I'm worried that my 1950's Harrison L5 lathe has been tampered with . Apparently , at the factory in Yorkshire , they spent a lot of time matching the bed to the base of each lathe. Removing the bed from its base is not recommended . I can see a odd shaped bolt on the bed and I feel that the bed has been disturbed at some point in time . The base is a heavy rigid cast and thick steel construction . I cannot see any obvious adjustment points . Would they have used shims under the bed mounts to align the lathe ? I recently fitted a 2hp motor and a VFD . It is a delight to use as it has a clutch/brake but it is rather noisy in top gear , sounds like a jet engine Mike

I was chatting to a friend of mine last night, he has a Harrison L5 and I was showing him this thread. He asked where about on the lathe was this odd shaped bolt. He also mentioned that whilst his is quite noisy, it is no more so than any other geared head lathe and to check the oil in the head. He said that when he got his, the oil was like treacle and took a lot of cleaning out. He couldn't remember what he used to refill it with.

HTH.

[morrisman]

I was chatting to a friend of mine last night, he has a Harrison L5 and I was showing him this thread. He asked where about on the lathe was this odd shaped bolt. He also mentioned that whilst his is quite noisy, it is no more so than any other geared head lathe and to check the oil in the head. He said that when he got his, the oil was like treacle and took a lot of cleaning out. He couldn't remember what he used to refill it with.

HTH.

Thanks HTH

I am using the hydraulic tractor oil in the gear head as most others are in geared head lathes , I think it is 63 grade .

The odd shaped bolt is one of the two holding the bed to the base , at the headstock end . The bolt in question has a square head , the other bolt is normal hex head .

Apparently it is possible to run these lathes up to 2000 rpm , I would have to wear ear protection .:no:

Today, I discovered the carriage lock bolt , it is in a sneaky location .

Some guy on the Harrison yahoo group suggested to me, I will lose torque by fitting the larger motor pulley as I have done.

Will the VFD I have fitted , counteract any possible loss of torque ?

I did also discover today , the cross feed has .017" of backlash travel

Mike

[Stustoys]

Some guy on the Harrison yahoo group suggested to me, I will lose torque by fitting the larger motor pulley as I have done.

I'm not so sure about that. Yes at the motor you will lose torque, but you'll gain speed. The Power will be the same.
3hp at the motor equals 3hp(minus losses) at the spindle. So the torque at the spindle will be the same at any given rpm.
Now in theory your losses maybe a little higher(hey they maybe lower for all I know), but in practice I doubt you'll notice.

[BaronJ]

Thanks HTH

I am using the hydraulic tractor oil in the gear head as most others are in geared head lathes , I think it is 63 grade .

The odd shaped bolt is one of the two holding the bed to the base , at the headstock end . The bolt in question has a square head , the other bolt is normal hex head .

Apparently it is possible to run these lathes up to 2000 rpm , I would have to wear ear protection .:no:

Today, I discovered the carriage lock bolt , it is in a sneaky location .

Some guy on the Harrison yahoo group suggested to me, I will lose torque by fitting the larger motor pulley as I have done.

Will the VFD I have fitted , counteract any possible loss of torque ?

I did also discover today , the cross feed has .017" of backlash travel

Mike

Hi Mike,

That square head bolt at the front of the base is normal. I've noticed that one on several Harrison lathes.

PS. HTH means "Hope this helps" :U