Reconditioning a Relmac lathe

**irving2008** · 11-06-2008

Kip, while I've seen references elsewhere to line boring I don't have the facilities to do that. And I'm sure the old-timers didnt go to that lengths. Also I don't see how you'd ensure the mandrel was aligned correctly with the tailstock if its just a short length of plaster.

Anyway I've found a local company in Watford that'll regrind the shaft by 4thou to bring it parallel and they quoted me £35 so hopefully I'll get that done this week and try again next weekend. I got some 2mm sheet ally and cut with my hole-saws two 2" washers with 1.25" centres and then took a 6mm hole in the top of each to act as air vents. This should be less likely to blow out. I'll seal the edges with fire-cement and clamp them across the bearing with a couple of small G-clamps.

In the meantime I've swapped out the 1.1hp 1-phase Atlas motor I had for a 1.5hp AEI (c1965) 3-phase with a Jaguar VXS-75 VFD courtesy of eBay (£75 the pair, bargain). I've also cleaned up and rewired the 0.5hp motor that came with the 3.5" Gamages lathe. This motor is proudly labelled 'The British Thompson-Houston Motor Co Ltd' and is very British in its heavy cast iron casing and gloss black finish. BTH became AEI in 1959 (and then were taken over by GEC in '67) but this motor dates from the late 40s or maybe early 50's and runs beautifully and silently.

**irving2008** · 12-06-2008

Originally Posted by Kip

I was thinking of a bar of plaster in the tailstock ready shaped and then pushed up to the headstock...Did that make sense?

Not really, although i can see where you're coming from. The challenge is that the tailstock is MT1, spindle is 1.25" diameter. You'd have to embed an MT1 arbour into the plaster when casting it in a 1.25"ID tube and how would you ensure its dead central and in line? Seems a lot of hassle to me...

Also a 1.25" reamer is about £70 which is way more than its going to cost to have the spindle reground...

I had a quote from a 'mobile line-boring' company who normally do much bigger jobs but it was silly money. If I had another working lathe and a milling machine I suppose I could make up a line-boring jig using 2 bearings supported on the cross-slide to hold a boring spindle with a small pulley to be driven from my 3phase VFD'd motor and using the tailstock centre to align it... but then if I had another lathe I could take a fine cut off the spindle, although getting an accuracy of 4 - 5thou over a 12" length would probably be tricky.

**irving2008** · 12-06-2008

Originally Posted by Kip

Here's me thinking everyone has lots of reamers and a working lathe ;) (mine was out of action for 2 days waiting on belts and I was beside myself) My previous one made the rivets for the Titanic.....I sure don't miss it :D Although I discovered that a LH thread requires modification to my 1992 Warco! Oh well it's all fun....Or savage amusement lol

Well when I get this one up and running a LH thread will be easy.... :) can do either, in imperial or metric....

The spindle is going in to be reground tomorrow AM early and I hope to get it back next week. They reckon it'll be 2h work inc setup as they'll need to make a MT3 arbour to hold the nose end and chamber the inside of the tail end to hold it on the grinder centres - they do all precision grinding between centres.

So this weekend I'll turn my attention to the Gamages lathe and get that set up on a board so I can try it out. At least the motor is running!

**Lee Roberts** · 16-06-2008

Originally Posted by irving2008

Well when I get this one up and running a LH thread will be easy.... :) can do either, in imperial or metric....

The spindle is going in to be reground tomorrow AM early and I hope to get it back next week. They reckon it'll be 2h work inc setup as they'll need to make a MT3 arbour to hold the nose end and chamber the inside of the tail end to hold it on the grinder centres - they do all precision grinding between centres.

So this weekend I'll turn my attention to the Gamages lathe and get that set up on a board so I can try it out. At least the motor is running!

Any joy with the Gamages lathe ? how did the regrind go ?

**irving2008** · 16-06-2008

Originally Posted by CheekieMonkies

Any joy with the Gamages lathe ? how did the regrind go ?

Should get the spindle back on Wednesday....

The Gamages started out well and went downhill.... :(

Working on a strap to repair it... to save repeating myself, look here: [ame]http://www.practicalmachinist.com/vb/showthread.php?t=160002[/ame]

**irving2008** · 18-06-2008

Got my spindle back :)

Cost much less than expected cos they did it as a 'homer' for cash as a favour and not through the books. All nice and shiney and smooooooooth :) and good within .0002 thou (well much tighter than I can measure anyway)

So weather permitting its 'pouring time' again this weekend!

BTW, anyone got a mill

I could get access to, as I'm not likely to get a milling setip working any time soon (apart from the lack of space!)

**Robin Hewitt** · 18-06-2008

Originally Posted by irving2008

BTW, anyone got a mill

I could get access to, as I'm not likely to get a milling setip working any time soon (apart from the lack of space!)

Rather depends on where you are.

I'm due south of London, stop just before it gets wet.

About ten miles west of Brighton.

**Lee Roberts** · 18-06-2008

What about one of these:

B'n'Q sell one like it for around £50, this one i use and it seems to be the best i have seen for that price range, or do you need a proper "Mill" ?

The spindle looks sweet mate, cant wait to see what this weekend has to offer !

**irving2008** · 18-06-2008

A proper mill - something that'll take a couple of cubic inches out of a casting in a relatively short space of time...

It could wait till I get the 'big' lathe running...

Didnt think B&Q sold milling machines, nothing on their website and cant say I've ever seen them. I've got a cheap pillar drill from B&Q - bought in the sale a couple of years back, reduced from £75 to £15 last one and with a damaged box but its not exactly a solid bit of engineering, struggles with 6mm into cast iron or 8mm into steel.... but hey, the drill bits cost more than the drill!