The only critical dimension is the thickness of the bottom part, this should suit your usual tool size.

Other dimensions can simply be 'in proportion'.

Neil

JasonB. Quite some time ago,(2012 actually) you made the comment 'cannot see the point in using a casting, easier and cheaper to machine from a block of steel or CI. Did you ever make one, and if so do you have a copy of the detail drg. for the 'B' version. If yes, any chance of a copy?. Regards Lynne.

I think this is the smaller one

Could be cut out of a bit of 80mm CI bar for £12.50 or a casting for £17

The stock removal from a solid bar is probably going to be 2 or 3 carrier bags worth of swarf. Do you think you're up to that for the sake of a few bob? I'd rather go for machining the casting if it's still there.

Michael W

Agree with Micheal that stock removal when machining from solid will be wasteful and hard work for typical Home Shop machines which tend to be rather lightweight for this sort of thing. The shape isn't exactly solid bar friendly either. Especially if you have to hacksaw it out the "armstrong" way! Built up from two plates and acentre block will be bit easier but the shape is still wasteful.

As many folk here already know I'm a great advocate of multiple built-up two slot block type toolposts as being the easiest and least costly "fairly quick" toolpost system for home shop workers. You choose the plate and centre block sizes to suit your machine and simply cut the requisite lengths off. Generally there is enough variety in avalaible thickness and width combinations that you don't need to cut both length and width of top and bottom plates. Bottom needs to be at least 1/4" thick so it doesn't bend when removed, top 1/2" to give plenty of thread engagement on the clamp bolts. Centre bar can be alloy if thats what you have. Makes tapping through for the hold together screws easier. Probably tap right though. Countersink type allen heads are best screws to use. I'd back up with adhesive.

SouthBend drivers like Anthony have an advantage in that not only is the compound slide Tee slotted but said slot also corresponsd to standard bar sizes so long Tee nutd can easily be made by screwing and gluing a narrow bar on top of a wider one. With the additon of a fixed stud and locking handle to make up completed toolpost and retainer units it becomes very quick and easy to interchange multiple too posts. In my SouthBend days I usually had 3 or 4 sets on the go. Mine were 4 ways but I pretty much never used more than two slots. An indexing device to ensure toolposts went back into the same position each time would have been nice but was never quite missed enough for me to get round to figuring out and making a good one.

Clive.

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Jason … A reminder of the opening question ^^^

MichaelG.

I've just noticed a bit of a down side to this design of tool post, what do you do if you want to hold say a L/H tool for facing or a boring bar? Make a second one that is the opposite hand and keep swapping them over?

There is a more economic way to overcome the above, I'll keep it to myself for now.

JasonB, drill the tool holding screws both sides so you can turn it over. If the bottom has to be recessed, you need to make a washer too.

Dave

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Jason,

(a) That's OK then … It looked like you were just using the opportunity to have an unnecessary dig at the "flimsy Myford".

(b) No, not really … I have no personal interest in the larger size, and anyway, I have already given a link to the catalogue which lists the castings.

Incidentally: My Myford already has a decent 4-way toolpost, and a Dickson, so; although I do find the Lammas design interesting, I am unlikely to make one for it. … I may, however be tempted to make a miniature one sometime, for the little Jason lathe.

MichaelG.

Edited By Michael Gilligan on 18/06/2016 20:22:01

Jason, Thanks for the information reference enlarging the type A to give the dimensions required for the type B.

Michael W, The casting will cost me £33,90 90mm square bar will cost £22 and 90mm dia. bar £13,55

With that kind of saving I am quite happy to make swarf, even to the extent of filling a small bag.

I have found all the other comment of interest. Regards Lynne.

Lynne, before you go rushing out to buy a bit of Cast iron round think about the grade. I don't know what the supplied castings are done in but may be worth a couple of quid more to get a piece of SG Iron bar, It would be heartbreaking if an overtightened screw snapped a corner off the toolpost. Or even a bit of free cutting steel, bit more work but cheaper than cast by half.

What do the metalergists think?