Before I am hung, drawn and quartered, for operating a lathe without guards, here is the proof that I have been sensible.
I recently bought a blank chuck backing plate on Ebay, hoping that it would fit my Colchester lathe. It was $AUD110 plus postage, which, if suitable, would be an excellent price, but it was a gamble. It was old new stock.
When it arrived I cleaned off the old, hard grease, and nervously presented the backing blank to the lathe headstock. It fitted perfectly! The seller had another identical blank backing plate, so I bought that one too. Components for the Colchester are not readily available, so I was very happy with this find.
I had a use in mind for both of the backing plates, and a few days ago I machined up the first one as per the following photos.
I was becoming a bit annoyed with my Asian HMC lathe. It was noisy, and whatever I did with respect to feed rates, tool types, material etc, I could not seem ever to get a really good finish, and it did not seem particularly accurate.
I had spent a fair bit of time getting it level, and adjusting the tailstock offset, but the settings never seemed to hold for long.
The base was as supplied originally. 2 fairly solid sheet metal cupboards with handy storage compartments, and a rather flimsy piece of sheet metal joining the 2 cupboards. Each cupboard had 4 adjusting bolts, ie 8 altogether, so levelling the lathe was tricky. But the worst aspect was that it all seemed very flimsy.
So I decided to make a new base.
A visit to the local scrap metal yard yielded up a 3 meter length of 300 x 100 x 16mm channel. Too heavy for 2 men to lift onto my vehicle roof bars, but easy with a fork lift.
Getting it off at the other end was tricky. But I managed to do so without damaging my vehicle.
I made the legs from some 100 x 50 x 3 or 4mm RHS, and welded it up. It all seemed heavy and rigid.
I measured and drilled the mounting holes for the lathe bed. The new base was at the same height as the original, so I was able to crow bar the lathe over onto the new base, hoping that it would not fall between the 2 bases. It weighs several hundred kilograms, so a fall would have been messy.
Amazingly, the bolts dropped straight into the new mounting holes, after some manoevering with a podger bar. Then I levelled up the base using bolts at the bottom of each leg, and a machinists level on the lathe ways.
Then I did some test turning.
1. The lathe is appreciably quieter.
2. The work finish is definitely improved. No unpredictable and odd grooves to mar the finish.
3. I have yet to measure the accuracy change.
4. Unexpected bonus. There is a lot more storage space under the lathe than there was in the original pokey little cupboards. Small items now live in the mobile chest of drawers unit next to the lathe, and big items such as the toolpost grinder in its box, are under the lathe.
I have been busy with selling farm equipment in my spare time lately and have only been in the workshop to get stuff ready for sale. New starter motor and starting solenoid on the mower, for example, took a lot of time to identify the problems, source spare parts and then fit them. Another story.
So to find some material to post I decided to show some pics of a lathe restoration I did several years ago. Actually, it was two lathes, both Smart and Brown, almost identical except that one was single phase and the other was 3 phase. They had been imported from UK by the seller, a second hand dealer, and sitting in his back yard, uncovered, for 5 years. There was quite a lot of extra stuff, such as 6 cross slides, a capstan tool changer, 2 complete sets of collets, several tail stocks, several 3 and 4 jaw chucks, and all of this was interchangeable between the 2 lathes. No lead screws, but 100mm of travel on the cross slide longitudinally. I think that these lathes are termed “2nd process” or something similar. They date from the 1940’s-50’s. The shape of the base, cupboard, and headstock really appealed to me, so I decided to try to salvage them.
Amazingly, after I cleaned up the slides and beds, they were in excellent condition. Whatever they had been coated with was incredibly effective. There was minimal surface rust and no pitting at all.
The following photos are mainly the single phase machine. Both machines looked fantastic after repainting. At some stage I will have to sell both machines, because I have totally run out of space in my workshop. I just really like the design and appearance of these lathes, and although I do not use them often, they are lovely to look at. My architect wife appreciates the designs and says that whoever designed them was as concerned about form as much as function, which is unusual in machine design.