I am in rather complete agreement with Howard. I once had a carbide insert parting tool. I now only use a (likely higher spec) Cobalt HSS material, in a stout holder. Sharpened occasionally with the belt sander, as required, the strip will last me several years – and I have a spare in stock but may never need it.

For hobby machines, a rear tool post is a very good improvement, IMO. I just put my lathe in power feed and let it get on with feeding/cutting – while I apply cutting fluid and get ready for the parted part coming free. I most certainly would not recommend anyone to buy a cheap parting tool, if fitted in a QCTP on a light-weight lathe. Just too much overhang for an easy life.

I expect my parting strip cost no more than a couple of your inserts.🙂

Edited By not done it yet on 23/02/2022 08:24:03

At the moment, there is a change happening with parting blades and inserts. The change is that instead of the insert having a taper shape to it, the new ones have a negative taper, so are slightly smaller at the front. The holder is now a flexure, and is expanded to take the insert. So in some cases, the replacement inserts are no longer available. That leaves them with buying a new blade or doing some deal with x number of boxes of inserts a discounted blade. I have not seen the free blade offers yet. In the 3mm for sure they are a through coolant design as well as a no coolant models. I have both the 2mm wide insert parting blades a a 1mm wide HSS blade that came with the original Dickson quick change tool post and holder sets. I got a spare HSS blade back in 1987 with the set and have never used it yet.

I really like the insert blades for parting off larger diameter stuff that is near solid or has a larger diameter than 1/2 inch in steel . They work well in most materials. For really small stuff or brass and Ali parts under 3/4 inch that are thin walled or need as sharp an edge as possible after being parted off, I use the HSS. The carbide will often leave a burr or quite an amount that will need to be addressed afterwards. Used carefully the Inserts will last a very long time and you can get a lot of parts parted off or grooved etc.

The insert parting works really well when parting off within 10mm of the chuck, even with 4340 bar.

Neil

I found insert parting tools rather expensive to use. I switched back to HSS but chose the T shape blades with chip breaker which work extremely well.

JB tools GN2 tips work perfectly well on my ML7.

I use a QCTP parting toolholder in the post on my MLS7. Cannot remember suppliers name. Quite a tight fit on the post because the tightening slot lip is thicker than my other toolholders which fit easily. I stop the chuck using the clutch and wind the topside back, slacken the toolpost, wind carriage along to hold tool against the chuck face for alignment, clamp up. Steady indeed with Guy Lautards cutting oil mix, low speed, around half normal turning speed for relevant metal. Works perfectly.

I have George Thomas type rear toolpost iron casting for which I will get a roundtoit some day,then I'll be able to set it up for instant use. All the time current satisfactory arrangement is only used occasionally, little incentive to get a roundtoit……

Hi I have an Iscar parting blade SGIH 19-2 and use tip GTN2 IC354 I use it in my rear toolpost and I have the original tip I installed over 18 months ago and still going strong.

I believe the part off tool needs to be straight and sturdy. I can part off more than 3 inch diamiter with little problems.

David

I have experienced mixed luck when using carbide insert tooling for parting off. I have HSS parting blades for my 10" and 16" lathes. It is nice to be able to take it to the grinder and put a slight angle on the cutting edge to eliminate those nuisance pips from the cutoff part.

I use a PeWe parting tool holder on a GH1322 lathe with a slightly modified JB blade and their inserts, it works fine provided I keep the cutting edge of the insert in good condition.

I machined an angle on the bottom of the blade to match that of the toolholder to ensure a snug fit.

I looked at PeWe parting toolholder and my bad language exclamation is unpublishable-is it gold plated? €85 = £68 approx. No way!

In my description above, I forgot to mention my toolholder has a clamp plate forcing the HSS blade tightly in position by tapers and I think, 3 caphead screws. Blade thickest I could get – about 3/32" to resist side – bending. As I said, works perfectly, happy boy!

Vaguely recall that it cost around £20-25.

I agree with you,Tony. See my one and only album photo, to view type of holder. I have just tried websites to find it for sale – no luck so far –

Arceuro, Reeves, Axminster, RDG tools, Rotagrip, Warco, Chronos.

John