Carbide insert crash course?

LVLAaron

LVLAaron

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New lathe owner... (PM1440GT) - I bought all of the turning and boring kits they offer with the lathe, so I have an assortment of tools that hold CCMT inserts, as well as several unlabeled inserts. Half are shiny silver (for aluminum) and the others are gold colored. No markings on them.

I'm shopping for parts on MSC direct and I'll be honest, I am overwhelmed with nomenclature and abbreviations. I want to get some quality CCMT inserts for steel and aluminum, as well as threading inserts. I have the engineers black book so I understand the shapes but... beyond that, I'd rather try and explain how to file income taxes to a 5 year old. :)

If someone could point me to some sets of inserts to get me going it would be greatly appreciated. And/or if there is already a great resource that lays this out for the complete noob, I would love to read it.
 
Try some high speed steel bits. They aren't hard to grind. Look up how to grind them in a post that one of the members here did. He did a great job explaining and showing how. All one needs is a grinder and a finishing stone.
 
I have the engineers black book too. Specifically for the insert pages. If you go to the section for inserts in inches it's the second page where you want to figure out how to use it. If I had it in front of me I would help more but it's in the shop. The most inportant thing, if you plan on shopping around on ebay for deals and inserts to try is to understand the size that works with your holders. Once you know that then you can try different ones and see how it goes. So you mention CCMT. That is a shape and a tolerance and a cutting edge profile but not the size. Sounds like you can hold a "C" shape insert. Size is a dash number after the profile like 332, 441, etc. first number is the basic size of the cutter. Don't mess this up because you can't even hold sizes that dont fit in your holder! See if what I mentioned helps you as you look at the page and have an insert that you can measure in front of you.
 
With CC** and CP** holders, remember, you can P in the C but you don't want to C in the P.

Meaning a CP** insert will fit a CC** holder but not the other way around.

Aluminum and other non-ferrous inserts are generally uncoated and sharp enough to cut your fingers.
 
Use those CCGT inserts (silver colored in kit) in the right hand turning tool and it will quickly become your goto. It will cut 416 stainless (barrel steel) like butter, great on 12L14 steel and aluminum as well. I buy the cheap inserts off of Ebay for maybe $1 each and they work as well as the original. Other than interrupted cuts, they seem to last just fine. I've bought a dozen others but all ways go back to that tool. I bought all left hand threading tools and don't use anything that came with the kit for threading. I can send you photos of left hand tools that i run upside down if your interested. Or you can dance with the devil and thread toward the chuck. The boring bars that came with the kit are decent once you get a hole opened up more than 5/8". I bought a cheap carbide boring bar off of Ebay 8mm diameter that uses the smaller CCGT inserts and it is amazing. Carbide has a lot less flex than the steel bars. I use it a lot, boring muzzle brakes, counterbores on 700 style actions, cone on Panda barrels.

If you have ever read the book "Chambering rifles for accuracy" Gordy Gritters lists some micro 100 boring bars that work well boring small holes. I also purchased 2 small left hand threading Micro 100 tools that can actuall get down to around 1/4" for inside single point threads. Anything smaller you'll use a tap.
 
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xr650rRider said:
Use those CCGT inserts (silver colored in kit) in the right hand turning tool and it will quickly become your goto. It will cut 416 stainless (barrel steel) like butter, great on 12L14 steel and aluminum as well. I buy the cheap inserts off of Ebay for maybe $1 each and they work as well as the original. Other than interrupted cuts, they seem to last just fine. I've bought a dozen others but all ways go back to that tool. I bought all left hand threading tools and don't use anything that came with the kit for threading. I can send you photos of left hand tools that i run upside down if your interested. Or you can dance with the devil and thread toward the chuck. The boring bars that came with the kit are decent once you get a hole opened up more than 5/8". I bought a cheap carbide boring bar off of Ebay 8mm diameter that uses the smaller CCGT inserts and it is amazing. Carbide has a lot less flex than the steel bars. I use it a lot, boring muzzle brakes, counterbores on 700 style actions, cone on Panda barrels.

If you have ever read the book "Chambering rifles for accuracy" Gordy Gritters lists some micro 100 boring bars that work well boring small holes. I also purchased 2 small left hand threading Micro 100 tools that can actuall get down to around 1/4" for inside single point threads. Anything smaller you'll use a tap.
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Never would have thought to use the CCGT inserts on steel. Will give it a shot. I have Gordy's books and have been to his in person classes :)
 
I'll strongly second getting David's book. AND learning to grind and use HSS. Knowing HSS can save you days of waiting for an order of inserts or tooling, and easily save you significant money for that one off specialty tool.

You want to start out with the right inserts, meaning that there is such a large variety of inserts and the corresponding tools to hold them, that if you just start picking randomly you will go broke. Quality inserts (name brand, such as from MSC) are definitely worth the money, but realize that typically you buy inserts in a box of 10. Plus a holder/tool. For good stuff you rapidly end up putting $200+ dollars easily into setting up tool holder, tool, and box of inserts. Add to that probably wanting inserts in each size/shape for both steel and aluminum, and buying quality parts. Some people have had pretty good luck with cheap inserts but not my experience.

Point being that one wrong tool choice or poor selection of inserts will pay for the book.
 
LVLAaron said:
Never would have thought to use the CCGT inserts on steel. Will give it a shot. I have Gordy's books and have been to his in person classes :)
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They won't break chips unless you take a big bite but with barrels, your not taking huge bites, you want a smooth finish. They'll have a much better finish than using CCMT.

I've ground HSS but much prefer to use insert tooling. I've yet to grind a HSS tool that gave as good a finish as CCGT insert.
 
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