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Carbide Insert Parts and Usage

TDegenhart

Diamond
Joined
Mar 26, 2011
Location
Geneva Illinois USA
I don't do enough with inserts to warrant special attention from a sales person so I will ask the questions here. What are pads and shims and what are they used for?

Tom
 
I don't do enough with inserts to warrant special attention from a sales person so I will ask the questions here. What are pads and shims and what are they used for?

Tom

Are you referring to the shim seat located below the insert on a standard pin/clamp style holder?
(kind of an insert below the actual insert)
Threading or turning or milling cutter?
Bob
(PS you will always warrant special attention from the sales people here)
 
You have just pointed out what little I know about inserts. The inserts in question are for turning and the holders and inserts are screw secured. But that is not the main question, I know so little that I cannot make an intelligent choice of holders and inserts. Most of what I have done has been strictly by accident. I have hoped to find a publication that covers all these intricacies but I doubt such exists except in company sales literature.

Compounding the problem is the jobs I do are tough on carbides, slow speed machines, difficult workpiece.

The specific job I have now is on a 12CK Monarch turning the thread from grade 8 bolts. Slow speed, intermittent cut, hardened thread. I do have flood coolant, This just tears up HSS.

100_0435.jpg

Tom
 
You may want to use a specific cutting oil for threading for this job, not the coolant. Bob knows much better than me, but I'd try a free cutting geometry with the idea that life is not critical, but lowering force and limiting surface "tearing" are helpful.

Speeding up SFM once you get used to the carbide may help too.
 
This holder or the SDJC-10-3B you asked me about do not use shims or seats.
Simple screw downs.
Laydown threading tools will often have seats on varying angles.
This so as to rotate the cutting tool for clearance on the front edge when threading.
As you cut this helix the stock is coming at you down the tools front flank. Hence higher helix, more twist needed using the same insert.
The thing I see here is basically trying to "Chicago" a bolt meaning leaving the thread but reduce the base behind it.
What is not working for you? This tool should handle that.
RPM? Depth per pass?

Even though supported the L/D here bad. Is a rough off threads on all parts and then a rerun for nice finish out of the question?
Chips are sliver colored but maybe hard to get to straw or blue on this machine. Yes I have to deal with that also on my SB.
Bob
 
Who missed that? Oh ,,I see.
A 45 degree lead, (or twist the holder shown) works better when ripping off threads.
You do not want to be "in sink" or aligned with the old threads.
The other side or zero lead works but is slower.
Bob
 
It's just weird that you have to do such.
In the auto world it is banned and you need special sign offs to do such for an assembly but........I think I did this last week on a clamp/fixture.
Bob
 








 
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