Myford 4 way toolpost

[John MilliganParticipant @johnmilligan78347]

Recently purchased a 5/16" shank parting off blade and holder for my Myford Super 7 and made a discovery that I hadn't thought of as am new to getting back into turning. Although the 4 way toolpost can take larger shank tools (probably up to 1/2"), if you are using a chip breaker type parting off tool, ie one that can't have the top surface ground away as it is already formed, then a 5/16" shank tool is the maximum you can use. Even then it puts the tool at a tiny smidge over the centre height but there is no way of changing the height other than reducing the thickness of the shank with loss of strength. Obviously larger shank tools can be held with the standard single tool clamp as they are direct onto the top slide but the 4 way adds in another thickness of the bottom flange. Hope that makes sense? John

Edited By John Milligan on 13/02/2016 09:31:32

[John MilliganParticipant @johnmilligan78347]

[RobboParticipant @robbo]

John,

This is a problem many newcomers to the Myford 4-way have found.

The 4-way was originally designed to use 5/16" tooling, of the "old-fashioned" type, as you have found anything more won't go down to centre height. The slot will of course accept thicker than 5/16".

My 4-way has the inner bottom edge of one of the slots milled away by 3/32" to lower the height of thicker tooling. As the 4-way is bolted down tight on the topslide I don't think this weakens it.

Phil

[John MilliganParticipant @johnmilligan78347]

Hi Phil, all my training was done using the "old type" tools so that is what I want to stick with lol as they are so cheap to buy tool steel and make all your various profiles to suit. At that size though I thought grinding a parting blade would be very wasteful and result in a fragile tip, hence the purchase of the chipbreaker type with holder. Don't want to cut the toolpost away as there is no going back from that but I meant grinding some off the flange of the parting blade holder thus reducing the height that way but would leave that weaker? It's all a learning curve again for me as training was on big machines, John

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