Small diameter turning tool

This topic has 8 replies, 7 voices, and was last updated 11 June 2012 at 21:32 by Terry Lane.

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11 June 2012 at 12:35 #92396
Graham Williams 5
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@grahamwilliams5
Made some valves for the Seagull I am building and wasn't impressed with what I got. So, been looking to get/make something along the lines of the Jabus small diameter turning tool. Anyone know where I can get one ( at reasonable cost of course LoL) or plans to make a similar one. Chronos list a similar one but the last time I checked it was OOS.
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11 June 2012 at 12:35 #6191
Graham Williams 5
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@grahamwilliams5
11 June 2012 at 13:21 #92397
JasonB
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@jasonb
We have had a few posts about these small dia tools, try a bit of searching.

J
11 June 2012 at 13:34 #92398
keithmart
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@keithmart
Hi

This looks simple enough to make

http://www.ship-expert.com/index.php?categoryID=112089&page=12&itemID=110861683068&type=Auction

Russin ebay, but the picture says it all
11 June 2012 at 14:04 #92399
Bubble
Participant
@bubble
Hi Graham

I turned some valves once by taking a single deep cut at fine feed from larger diameter bar. Its wasteful in material but so is making a possibly use-once tool to do the job. You need something like free-cutting silver steel or maybe (free-cutting) EN8DM and a very sharp tool especially if using a form tool for the under-head radius. No top rake, EP lubricant such as Rocol, and make sure the tool is not above centre height, maybe slightly below. Experiment with cutting speed & feed.

It works on the basis that the uncut stock bar, being large in diameter, is stiff, and the part already turned sees no further cutting force. I finished the stems to size by diamond lapping (diamond paste, balsa wood tool) before parting from the stock material.

Worked for me!

Jim
11 June 2012 at 14:36 #92401
Tomfilery
Participant
@tomfilery
Graham,

If you have a "standard" QCTP with two tool positions set at right angles to one another there is a neat trick I saw demonstrated by Jake Sutton on the SMEE stand at Sandown Pk last year. He used a support (as per the Jabus) in the tool position at right angles to the lathe bed axis and a TCT tool in the other position to cut the material. If I recall correctly, he said that once you'd set up the cut (to get the desired diameter), you had to leave the support loose, until everything was running and then lock it in place.

He describes this (and there is a picture of it) in P575 of ME of 21 Oct 2011 – in his article "My 2 1/2 inch Gauge Adventure".

I haven't tried it yet, but thought it looked an excellent idea and less fiddly than the Jabus.

Appreciate that my description may confuse some, but refernce to the article should make it clear.

Regards Tom
11 June 2012 at 17:39 #92406
NJH
Participant
@njh
Graham

I bought one of these a while ago from here. It works well – for instance I have used it to run down some bar to make some 8BA studs. Not too difficult to make one yourself I guess. Note a couple of the inserts are supplied with the tool and it's a quick job to make some more.

Regards

Norman
11 June 2012 at 19:48 #92412
Graham Williams 5
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@grahamwilliams5
JIm. Thanks for your reply. That was essentially what I tried to do but if I took deep cuts to get the diameter I wanted it stalled the lathe (belts tight but didn't want to overload the clutch so didn't screw adjusters right down) so tried to creep up on finished diameter but always ended up with a taper . I was using Silver steel. ( lathe checked to make sure it was turning true)

Tom. That looks a possibility . Thanks very much.

Jason. Tried searching but perhaps not so good on the old computer, grandaughter arrived earlier with her Mom and she is going through it with me in case there is something out there, other than what's been advised by Jim/Tom/Keith
11 June 2012 at 21:32 #92416
Terry Lane
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@terrylane
At the risk of repeating mysellf …..
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