How would you design a extra mini lathe (Adept size)

I like the concept of the Adept size super small lathes but it must be reluctantly admitted (or shouted with a megaphone from the rooftops) it wasn't that well made. The Wizard I own is certainly better but still no Schaublin.

Has anyone ever made a lathe of similar capacity out of stock metal? I have access to a lathe and mill (though the only tools I personally own are non functioning ).

I have some vague sketches and anything that has bearings and proper more tapers would probably be an improvment over an adept but I wouldn't call myself an expert lathe buillder so I thought I would just throw a line out and see if anyone has made one before and could show how they went about it or give hints. I did read through the Gingery lathe book but thought some parts of it made things excessively bodged in the name of saving pennies.

Many years ago LC Mason built quite a neat one, I think it was from stock materials but I cannot remember much of the detailed stuff.

He wrote a book called 'Building a Small Lathe' (not sure if it's still in print though).

Edited By V8Eng on 15/09/2015 21:34:53

Yep - that's quite right - L C Mason wrote a book Building a Small Lathe. This was made from stock materials. I just had a search through my bookshelves and can't locate it. I recall that it was a small machine and LOTS of work to make and quite a lot of material to buy first. The book is still readily available - usual sources!

I think that if I was in the situation with no lathe, and desperate to get one, I would opt for the largest of the mini lathes that I could run to ( Arc for example) have a selection.

Norman

His was backgeared and screwcutting, for the cost of a set of gears on the internet you could buy many lathes.

[Thought some parts of it made things excessively bodged in the name of saving pennies.] I think you mean botched ! Theres nothing wrong with any thing thats been bodged, the bodger in the lodge does some pretty good bodging !

bodge.

Oh of course But then there is having the user gauge their holes with a feeler gauge and an inside calliper because a vernier calliper would be too expensive

I'm glad I'm not the only person who distinguishes between 'bodge' (making do with available materials) and 'botch' (screw up).

Neil

But if you are making a lathe then why would you not cut your own gears, could be done for the cost of the bar stock and a few bits of silver steel to make your own cutters

L C Masons book is still available from Ebay and I think TEE Publishing may stock it.

Started to make one of these at Witney Tech College evening classes in the 80s. Still have the bits (I think!!) among the stored recovered rubbish from the flood. Last seen it was very rusty but (by my standards!!) not bad. I had got as far as the top slide and cross slide plates before having to give up the classes. I had also managed to cut the lead screw - highly chuffed at that!! Given that I was able to progress it that far, anybody with an ounce of REAL basic engineering skill could make a really nice little home build job of it.

rgds

Bill

According to my dictionary they're the same thing - "to make a mess of"

Andrew

LOL It's funny how often people comment on word use like this but don't check.

John

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I seem to remember a very simple design appearing in one of the model engineering mags some time ago based on using a bar for the bed. Might have been MEW. Probably square bar rotated by 45 degrees.

There are some interesting ideas from older lathes. For instance one plain lathe uses a totally different saddle for screw cutting. That is then moved along the bed to where it's needed just like the usual slide arrangement.

Some old cheap lathes used nothing more than a pair of round bars for the upper slides rather than dovetails. Some also used Myford type bed rails on the upper slides.

My father reckoned the best way to get a super precision small lathe was to make one myself. I'd been thinking in terms of using flat ground stock sections. His attitude was why - ordinary steel sections only vary by thou's. Makes sense really as things are going to have to be fitted and dowelled / double roll pinned.

He mentioned that an interesting lathe with an unusual design of bed was produced by one manufacturer just after WWII. A slant bed. They can have larger swings and be very rigid compared with ordinary beds. The saddle hangs down from the back so the bearing surfaces can be very large. Trouble is that the cross slide needs to run horizontal. I'd guess he was thinking in terms of a very thick fairly wide steel section. I feel it would be too difficult to make but he might have been suggesting a rather unusual spindle to bed arrangement - bed flat and spindle moved back rather than on centre. Not sure. He'd usually only gave me clues especially as he got older.

One thing that is a fact is that plain bearings are best. It struck me that oilite's could be used to save keeping on having to make them. Maybe even running on needle roller bearing inners pressed onto the spindle. it wouldn't be too much of a problem to make an attachment that could be fitted to the bed to finally size both the bearings in the head stock and the tail stock by hand. It should be just a case of removing a few thou of material. From what I can gather this was done by people a long time ago to save the pain of having to accurately scrape them. The manufacturers have used similar ideas even jigs to position and size them often rotating so that both bearing can be at the same height and alignment.

Thrust - a race of some sort will be best for that but for insanely high speeds I suspect Pultra used hardened steel running against phos bronze as I feel that the thrust bearing they used on some would have a hard life at 10,000rpm.

I think about the slant bed and wonder how every now and again. I wonder if what he was thinking about would be better described as a slant head. In my minds eye it makes sense.

John

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Indeed, if they did (or they knew any practising bodgers - green woodworkers, a very skilled craft) they would know the truth:

www.potterwrightandwebb.co.uk/wood-2/a-bodger-is-not-a-botcher

Neil

Collins gives the info a bit quicker than oxford Neil but both infer the same thing -

**LINK**

After all Collins is concise.

You'll get me going on the phrase "this begs the question" if and when comments crops up.

John

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I was accused of being a bodger the other day, my reply was -" yes and it's still working." Rather proud of my bodging.

I'd look into the possibility of using ball screws and linear guides. We had a small CNC mill at work that featured both and that seemed to work well enough.

Hi John W1 I think that it was in Engineering In Miniature.

Language evolves and changes; usage counts more than dictionaries, they can only play catch-up. The resurgence in green woodworking over the last thirty-forty years the distinction has become stronger.

The opposite trend is how jury-rigged (an operation demanding great skill) and jerry-building (the opposite) have become conflated in the term 'jerry-rigged'.

Neil

I'd probably use something like a C20 ER20 milling chuck and some chunky pieces of ground flat stock pinned and bolted together would make a good bed combined with linear guides. Thick walled box tube for the head and a variable speed drive would complete the basic structure. Biggest problem I see is aligning the spindle with the bed and fabricating/aligning a tail stock.