johnsmachines

machines which I have made, am making, or intend to make, and some other stuff. If you find this site interesting, please leave a comment. I read every comment and respond to most.

Tag: lathe

More Crankshaft. Roughed on mill, finished on lathe.

This is the first big end bearing.  The bearing surface was roughed out on the mill (held between centres using the dividing head), then the excess  around the flanges was removed on the mill (with the workpiece held in the milling vice),  then the bearing surface was finished in the lathe.

This is the first big end bearing. The bearing surface was roughed out on the mill (held between centres using the dividing head), then the excess around the flanges was removed on the mill (with the workpiece held in the milling vice), then the bearing surface was finished in the lathe.   There is a crankshaft buried in that lump of steel.  I just have to remove all of the bits which are not crankshaft.  (apologies to Michelangelo).

Making a start on the second big end. There is a block of steel loctited in the first big end so it is not bent when the workpiece is compressed between centres while the other big ends are machined. The second big end is yet to be finished on the lathe.

Making a start on the second big end.
There is a block of steel loctited in the first big end so it is not bent when the workpiece is compressed between centres while the other big ends are machined.
The second big end is yet to be finished on the lathe.

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A slightly different view showing the block glued into the first machined big end, and the almost finished second big end. This is the milling machine setup.

LATHE OBSESSION

I have a disease, and I do not know its official name, but it involves a compulsion to buy and collect lathes.  At last count, I had 9.  Varying from a 6mm Boley jewellers lathe, to a 2 tonne 400mm swing behemoth which occupies a large space in my workshop.

Well, now it is 10.

I noticed this one on Ebay, and thought that restoring it might be a nice project.  (that is, after finishing the triple expansion marine engine, the Burrell traction engine, the beam engine and the Bolton 7 horizontal engine.  Plus tidying up the workshop.  Plus selling off the remaining farm machinery.  And all of the jobs which SWMBO has lined up for me.)

It is an Australian made (I believe), TNC lathe with 6″ between centres, and a swing of about 3″ (centre about 1.5″ above the bed).  I paid the “Buy It Now” price of $A150, because I lusted after it and did not want to risk missing out in auction bidding.  Plus $A40 rather exorbitant postage, considering that it weighs only a kilo or so.

It needs mounting on a base, a new handle, a drive pulley cluster, possibly a new headstock shaft, a 3 jaw chuck, a motor, and repainting.  The paint looks original and is a horrible job.  I will give it a new colour, suggestions welcome.  The tailstock centre needs regrinding.  It is a tiny taper, about 1/4″ diameter.

Lathes.co.uk is not currently available so I do not have much information about the provenance, age, etc.  My guess is that it would be 1950’s 1960’s.

(lathes.co.uk is again online, thank you Tony!  The TNC was made in Australia under licence, a close copy of the Super Adept which was made in the UK.  Still not sure about the age.  The Super Adept was made as early as 1937.  The Australian TNC was listed after WW2).  The brass handles on my lathe are probably not original.

The cup of coffee is for scale.

The cup of coffee is for scale. (for sale if the price is right!)

4 jaw chuck. Not sure what the gears are for.

4 jaw chuck.  I have a nice 3 jaw TOS which will be installed.
Not sure what the gears are for or even if they belong to the lathe.

 

The muddy yellow-green-grey paint was revealed after an initial de-greasing.  The handles are brass.  All of the slides work, and there is no discernible wear.  The gibs are brass. One handle is broken.

The muddy yellow-grey paint was revealed after an initial de-greasing. The handles are brass. All of the slides work, and there is no discernible wear. The gibs are brass.
One handle is broken.

An Improved Lathe Stand.


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.

The lathe on its original cupboard base

The lathe on its original cupboard base

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.

Cutting the channel with the drop band saw.

Cutting the channel with the drop band saw.

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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.

The new base.  The channel is barely visible under the lathe bed and behind the legs.

The new base. The channel is barely visible under the lathe bed and behind the legs.

Levelling bolts at each corner

Levelling bolts at each corner

 

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Showing the channel welded to the legs, the cross piece, and the levelling bolts.

 

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.

LATHE RESTORATION

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.

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The two Smart and Brown lathes sitting on my ute, ready for unloading. One was made of cast iron, the other of cast aluminium.

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The capstan, after partial disassembly.

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The capstan was frozen solid with rust. I had to crack it to complete the disassembly, by putting it a 20 tonne press after pre-soaking with WD40.. With huge pressure, it eventually went “bang”, and then showed some movement. I was then able to take it apart. Nothing broken or bent.

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The collet closer on the three phase machine, after some cleaning and lubrication, and prior to disassembly.

The single phase S&B after restoration, painting, new tool post, attention to motor and wiring and switches.  A lovely, quiet, accurate machine.  Just no thread cutting.

The single phase S&B after restoration, painting, new tool post, attention to motor and wiring and switches. A lovely, quiet, accurate machine. Just no thread cutting.

Cast aluminium brand plate.

Cast aluminium brand plate.

I did install a quick change tool post.  No apologies.  Not historically accurate, but very useable.

I did install a quick change tool post. No apologies. Not historically accurate, but very useable.

A good selection of collets.

A good selection of collets.

New, modern belts for both lathes.

New, modern belts for both lathes.

The 1 morse taper tail stocks are a pleasure to use.  Smooth, no discernible play.  Modern lathe makers could take a lesson from these handles.

The 1 morse taper tail stocks are a pleasure to use. Smooth, no discernible play. Modern lathe makers could take a lesson from these handles.

The motors on both machines were checked by a motor rewind specialist.  No major problems with either motor.

The motors on both machines were checked by a motor rewind specialist. No major problems with either motor.

Collet chuck for CNC lathe

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I made this ER32 collet chuck for my Boxford CNC lathe.  Actually I made 2 chucks, but the first one had 0.03mm runout, so I made this second one more carefully, and it has no measureable runout at all, at the chuck or 50mm out from the face. The material is stainless steel, so it was difficult to drill the holes and tap the threads, and I used a few tungsten carbide inserts.  I am very happy with the end result. Thanks to Stuart T for the design.

I made this ER32 collet chuck for my Boxford CNC lathe. Actually I made 2 chucks, but the first one had 0.03mm runout, so I made this second one more carefully, and it has no measureable runout at all, at the chuck or 50mm out from the face.
The material is stainless steel, so it was difficult to drill the holes and tap the threads, and I used a few tungsten carbide inserts. I am very happy with the end result.
Thanks to Stuart T for the design.

TOOLREST FOR GRINDER

This contraption is a toolrest for a benchgrinder. it was an early project when I started metalworking-machining, and was made mainly on a milling machine, and lathe.
The tool to be sharpened on the grinder (lathe cutter, chisel, screwdriver, saw blade etc) rests on the top platform. The top platform can be adjusted to any angle in 3 dimensions, using the brass handles. The 2 brass knobs are to present the work to the grinding wheel, and are graduated in thousanths of an inch. Sounds complicated and it is.
Designed by Harold Hall, with plans and instructions in his book “Milling, A complete course”.
The wine glass is for scale only. Although the level went down during the photography session. Must have evaporated.
I have nickel plated several components of this tool ,because of surface rust.

Machining the flywheel