Tangential lathe tool holder

Vic, Are you known as "Firebird" on another forum? I'm sure I've seen this tool before .. John

I use a very 'low profile' toolbit clamp.

Neil

Nice work Vic.

I don't have that kind of artisic talent

My version is a Mike Cox variant. For the clamp I have counter bored a hole similar to what you have done but pull a tapered wedge into the hole, a bit like a cotter pin on a push bike crank. I have only just made it so I don't if it clamps better than a traditional clamp, only time wll tell.

Cheers Michael.

The tool shown in the Autumn 2009 M.E.W. article taking 1/8" toolbits gave such impressive results that, recently, I made up a beefed up version taking 5/16" toolbits.

Sharpening,

The original Sharpening Fixture called for a 20 degree angle, (corner to corner), but the drawing seemed to suggest that the angle of the bit would be 30 degrees. Maybe that meant along the side? Any comments?

The 30 degree angle recently mentioned will results in a thinner and weaker cutting edge.

My original sharpening jig was made to 20 degrees, and the 5/16 bit was ground to that on a Worden.

Both tools work well for me, (and for at least three others used on various lathes), having been sharpened at 20 degrees).

Using a 1/4 BSF clamp screw and nut, no sign of slippage has been evident, when taking a 0.100" cut.

It appears to be capable of taking a 0.0005" cut just as well!

I do like the idea of using a tapered wedge to clamp the bit; must try that.

Currently, it has made the usual CCMT060204 tipped tool redundant. Wonder how long the honeymoon will last? Seems to stand my brutality better, and so looks to be cheaper to run!

Am now starting a holder to take 1/8" round toolbits, for use as a finishing tool, to see if an even better surface finish can be produced, than the "standard" tool used at low speed with neat cutting oil.

Howard

I've used round HSS in my bought holder to good effect. I've struggled even on a green grit wheel to sharpen some old broken carbide milling cutters but when I do I'm sure I'll be able to cut some really hard stuff should the need arise.

Couple more pics to clarify the tool angle of 12 degrees forward and 12 degrees toward the chuck.

Edited By Vic on 21/08/2014 22:32:44

Finally got around to making a right hand tangential toolholder to complement the L.H. one I made following the MEW article by Michael Cox. The step on the top is machined to the centre height of my lathe which makes setting the tool height a doddle. I will be doing the same on the original one when I get a round tuit.

Vic, have you a drawing of the tangential tool holder you have made? What grade steel did you use also?

Clive

Hi Clive,

I don't have a drawing as I milled it as I went along! As for the steel, I have no idea. It was made from bench (gym) machine weights that were going for scrap. Definitely steel though of some description. Sorry I can't be of more help.

Thanks Vic, I will see what I can find under the bench.

Clive

Hi Clive,

don't know which size HSS toolbit you intend to use, here is a drawing of one using 1/8" square bits, may be you'll find it helpful.

Thor

Thank you Thor, that will give me something to start from, I do have memory of using this type tool many years ago on a machining course in the army.

Clive

Vic, very nice tool, looks the business! Just one query, was there a reason you made the bit where the HS tool bit is held thicker than the rest, or did it just come out like that?

Chris

Only because it ends up thinner at the end where it's milled at 12°. It can be the same thickness all the way through though if you like. I started with quite a large lump of scrap steel so I needed to thin it a bit for the toolpost. The reason for the deep step was to keep the toolbit clear of swarf, it also help to see what's happening at the cutting edge. Really though it's just a matter of making it to fit your Lathe. Within reason though bigger is better if it improves rigidity. If I get a minute I'll take some more pictures at different angles if it helps. It's not quite as clean now though as it's had a lot of use, it's my most used tool!

Edited By Vic on 29/08/2014 21:36:22

Good enough reason Vic, hadn't thought of that angle but it makes sense. Yes please, more pictures if you can please, a picture is worth a thousand words and all that!

Chris

I knew I'd seen that tool before

http://www.homemodelenginemachinist.com/showthread.php?t=22458&highlight=tangential

Very nicely made.

Can someone post a pic of this thing "at work" - public declaration of ignorance - I don't know how it works!

Steve

Hi Steve

HERE is a good example. They are very effective and, with the exception of special form tools , will cope with most turning tasks. In addition sharpening and adjustment is very simple.

Norman

I've made several holders for 1/4" tool bits based on Michael Cox's MEW article, for me and some friends. I designed a slightly different sharpening jig to those shown so far; it works just fine and needs a smaller chunk of metal.

Here are a few pictures, plus the design of the jig.