I use brazed carbide and has for special cuts like grooves and radius.
Also my cutoff tools has. Usually grind a tool and use it then save it for future use.
Money to spend on inserts and holder for lathe
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Also my cutoff tools has. Usually grind a tool and use it then save it for future use.
Sorry HSS
I use carbide and brazed on bar of steel. I do this for deep cutting of A36 steel which need a high rake angle for best cutting. I do same with hss steel for short runs.
Dave
Roncohudd , what triangle inserts are you using that give you 6 corners ? Would that mean that the insert has 0 rake ?
I like the idea of the diamond inserts . Do you need two different tool holders to be able to use 4 corners or is there just 2 corners per side ? I've been reading on inserts for a while & it's a pretty overwhelming world .
thanks
animal12
I like the idea of the diamond inserts . Do you need two different tool holders to be able to use 4 corners or is there just 2 corners per side ? I've been reading on inserts for a while & it's a pretty overwhelming world .
thanks
animal12
Ozwes007
Well-Known Member
Just a little info. The corner radius on a carbide insert is what you need to understand determines your minimum depth of cut and optimum feed per rev. The type of edge and clearance angles determine what it should cut like(in broad terms). The tool holder can be positive, negative or neutral so a zero rake clearance angle insert should be added to the holder’s rake to obtain true clearance angles. Also carbides don’t actually cut like HSS or Carbon Steel bits, they have more of a rubbing action that relies on correct speed, depth and feeds to give a positive result. A good carbide tip should last between 6 to 8 hours per tip of an insert, as such on a double sided triangular insert would give you 36 to 48 hours of continuous accurate cutting. ( use a tip every week of full time work 
)
)I do think that most machining done by hobbyists is well served with HSS tooling. I do have my fair share of insert tooling and it has its place, sure, but I don't want to afford the 'throwaway' prices. I have about four complete toolposts, most of which wear HSS tooling, so the QC toolposts really aren't relevant. Toolposts are relatively easy to machine, so why bother with the QC type? Much quicker to change the whole post. Then there are times when my insert has just rubbed any edge it had right off and I do 'touch'em up' on a green grit wheel. Are most of our milling cutters carbide? I have a fair selection of carbide (easily broken/shattered) cheapies in the smaller sizes and the larger cutters are HSS and these I routinely 'touch up' offhand. Quite successfully, too. I've had a couple of friends who had very little idea of HSS tooling and they used to spend lots of $$$ on inserts. I suppose the question is if you really do need inserts all the time? Do you, really?
Picture of one of your "Toolposts"? I have no idea what you mean by changing toolpost quicker than a QC toolpost.
ajoeiam
Well-Known Member
I don't think one does but then I was in an environment where I had to use brazed on carbide tools almost all the time.
Easy to get at least decent that way.
Now if you aren't into sharpening or somewhat scared of the art - - - well then inserts are the way to go.
Inserts do excel at repeatability.
Then you exchange the corner for a fresh tip - - - You KNOW that you're within a thou if not less of the last place (unless of course you were really hammering that previous corner - - - grin!). (I have destroyed more than an insert or two - - - LOL! Occasionally on purpose too.)
It term most know (QV toolpost)
It typically a Aloris type there other types
https://www.mcmaster.com/31805A11
Dave
Hi Dazz, I think you are right: Inserts are meant for machines with bags of power, and stiffness, for high speed cutting and fast material removal, well quenched to avoid overheating and distortion (of the component being machined), and are very cheap in industry where they buy them by the bucket load and change to a new cutting edge every shift or 5.
But many of us do small cuts at lower speeds, because we have "little", "hobby" machine tools, without the power to need or properly use carbide inserts. I use some carbide - some as broken bits I have brazed onto steel bar and re-ground to sharp edges that make very good hobby tools. But I also have HSS and old "tool-steel" tools that all work very well, at their suitable speeds, cuts and feed-rate, on the right material and application. And you are right that, if you can power the cutting rate for carbide, it is the best thing since ... ??
K2
But many of us do small cuts at lower speeds, because we have "little", "hobby" machine tools, without the power to need or properly use carbide inserts. I use some carbide - some as broken bits I have brazed onto steel bar and re-ground to sharp edges that make very good hobby tools. But I also have HSS and old "tool-steel" tools that all work very well, at their suitable speeds, cuts and feed-rate, on the right material and application. And you are right that, if you can power the cutting rate for carbide, it is the best thing since ... ??
K2
I've been using the Aloris style tool post almost forever. My small Atlas has the type A piston type, the Grizzly 13 x40 has the wedge. I don't have a problem with either one. I get my tool length and height set and can go all day. Only change inserts when needed. Real time saving.
That is a QC tool post, which probably a high percentage of us are using. me included. I know what a QC toolpost is. My question was to WAZRUS, as he posted
"I have about four complete toolposts, most of which wear HSS tooling, so the QC toolposts really aren't relevant. Toolposts are relatively easy to machine, so why bother with the QC type? Much quicker to change the whole post. "
That still does not make sense to me, if he changes the readily machined toolosts, rather than use a QC toolpost, what is he talking about? I change toolholders on my Aloris type QC toolpost in seconds.
Richard Hed
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Regular quick change are still easier and faster. I buy the cheapest ones I can find. If I can ever get my milling machine up and hopping or waddling, I'll make my own. Even the cheapest I can find at shars are too expensive for a a cheapo like myself. Not only that, but the ones I bought at shars, I had to sand down about 2-3thou to fit my TP. Still, they are good QCTPs. I have about 12 and would buy more except at the moment I really don't need extra. I needs a "no pressure" knurling tool, however.
I started out with a 1918 SB worn out lathe with a rocker style (I calls them ducks, they walk like a duck, chatter like a duck, what else could they be?) which was hell to deal with. I was really excited to get a four way post as I thot I would get four tools into it and just rotate them, but that did not happen, I was lucky to get two in. The constant shimming and adjusting was maybe actually WORSE than the DUCK!
When I finally got the QC I was happier than a duck with new duckings and a nice safe pond. I have one on each lathe. I was looking ath the British style QCTP (or maybe that is Euro style?) and wanted to make one just for the s***s and giggles. But I also saw a home version that looks really nice that someone did. I thimpfks there are efen plans for them. Would like to do that too just for the giggles.
They are actually simple in design compared to a lot of things we do. The only real different operation is the bevels which one needs a bevel tool for to make it easy. I'm sure I could do it with out the bevel cutter, but it would be like "ducking" it.
It usually works better when I add the link in my post
http://www.cdcotools.com/animal
http://www.cdcotools.com/animal
Yeah, I change mine in as many seconds, too. Some of the posts wear insert tooling, others HSS and as somebody (animal) suggested, there are four different tools available on each post. Just undo the top screw, turn the post around, and you're away. What could be simpler and without the expense of so-called QC toolposts? I have one which has tooling for O-rings and the other side has a cemented carbide threading tool: that's a 2-way job. Then there are three other 4-way jobs and lastly, there's a 3-way, triangular (sort of) post, which allows some unusual approach angles and often can save changing and packing tooling, if it ever comes down to that. My toolposts are made from 4"x2" black mild steel solid. The tool grooves are drilled out from the solid, then milled to final size and shape, having drilled the hole for the post itself. Simple, but can be heavy going. I have also made another post attachment which carries a small hacksaw blade in a reciprocating frame. The reciprocation is by hand, but the thing is very handy for slotting small screws, when I can't be bothered setting up a mill. An issue with tool posts are the setscrews. Just any 'ol setscrew won't be much use, as the ends will mushroom and getting the screws out might be a problem, if you ever wanted to. There are very much hardened, square-headed toolpost screws available- or there used to be - and these are the goods. Socket-head capscrews will often suffice, being usually higher-tensile and tougher, but not as durable as the proper square-heads. I'll send some pix of the toolposts: I'm not in my shop at present. I have always thought that tool changing is most conveniently done with a collection of posts: a bit 'old fashioned', if you like and I've never been convinced of any real benefits of the QC posts or attachments.
It seems there is a terminology 'issue'. i have attached some pix of several of my toolposts and I feel sure no explanation of them all is needed. Their application, etc is obvious. One worthy of note, though is the decidedly 'old school' single toolpost, with the central setscrew. this is usually used with a forged steel toolholder. the toolholder itself is often 'bedded' on a spherically-faced 'washer', with what used to be known as a 'boat' underneath. The boat allowed the tool and its holder to be orientated 'on centre'. The packing to centre is not much of an issue for me, as there are about twenty tool holding grooves available. I don't think many lathes these days come with one of the single-post holders. Tool holders themselves are still available and do allow very ready adjustment of tools to desired heights. Toolholders are a good item to have if you're using a shaper, but the shaper holders are often specialised for that machine. Some carbide insert tooling is also visible and as I've said, carbides, both inserted and cemented, have their place, at least in my shop. There was a third photo, but the system seems to be having a hernia.
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