Why pay for expensive commercial cutters. Make them yourself and save a bundle. Here is the process of making two common types of holders for ceramic inserts.
This is a RH holder. RH often causes confusion since by RH we mean that the feed is to the left while the chip peels off to the right. Hence RH is determined by chip direction, not feed direction.
Start with a steel blank and an insert-
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/inserts/PICT0327Medium.jpg)
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/inserts/PICT0328Medium.jpg)
layout the RH pattern --
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/inserts/PICT0350Medium.jpg)
Look close at the previous pic, because here it becomes tricky!! Since were using TNMA inserts we need a 5 degree offset (just like in the other holder), but this time at a 60 degree angle. So we will need to machine a compound angle. To accomplish this I used an adjustable machinists vise. Unfortunately I forgot to take a pic while machining -- but here is a pic of this vise
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/inserts/PICT0363.jpg)
Set one axis to 60 degrees and then tilt the vise 5 degrees for the relief angle -- voila -- you have a compoung angle for the rake.
here is what it should look like -- 60 degrees sideways and 5 degrees tilt.
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/inserts/PICT0352Medium.jpg)
The machining and drilling process is exactly the same as outlined in the other thread. Use a fileto handfit the insert if necessary and use a loose insert to center punch the hole. Here is what you wind up with --
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/inserts/PICT0354Medium.jpg)
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/inserts/PICT0355Medium.jpg)
scribe the next cutting line to form the pocket -- 60 degrees, and make the cut.
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/inserts/PICT0356Medium.jpg)
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/inserts/PICT0357Medium.jpg)
Next, mill a 3 degree relief on the bottom for clearance.
This is what the finished product should look like
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/inserts/PICT0358Medium.jpg)
Here you have it; two indexable insert holders -- for next to nothing.
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/inserts/PICT0361Medium.jpg)
Enjoy!!!!
In keeping with our GH "DIY" philosophy, I added a long roughing boring bar to my tooling inventory. The fabrication is pretty much the same as in two previous threads on making RH and 60 degree insert cutters
http://www.thegaragegazette.com/index.php?topic=78.0 (http://www.thegaragegazette.com/index.php?topic=78.0)
http://www.thegaragegazette.com/index.php?topic=79.0 (http://www.thegaragegazette.com/index.php?topic=79.0)
The insert is the same (Kennametal TNMA insert), but since it's a roughing cutter, the 5 degree offset isn't really necessary
Here are the materials
1) 10 inch 1/2" square steel bar from Tractor Supply -- (comes in three foot lengths for $6.00)
2) TNMA-333 inserts bought bulk on ebay -- got 100 of them for less that 25 cents each
3) Some 5mm hardware for mockup
This cutter will have an insert on each end -- hence a dual use roughing tool. One side will be for boring, the other for smoothing
As before I simply mark the square bar with the position of the insert in order to mill the seat pockets.
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/misc/PICT0155Medium-2.jpg)
The insert is then fastened in place with a simple nut and screw
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/misc/PICT0157Medium-1.jpg)
Once the insert is taken care of, the bar is milled to make 6" extension
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/misc/PICT0156Medium-2.jpg)
Nothing fancy -- here is the finished bar. No compound angles to worry about, just a straightforward flat milling task.
(http://i357.photobucket.com/albums/oo18/goodfellow_2004/misc/PICT0158Medium-1.jpg)
For the price, it's worth the 45 minutes to an hour to make one of these things.
You are having to much fun interesting/informative post.
Well done
Pep
Quote from: SteelWheels on Jan 20, 2025, 05:55 AMYou are having to much fun interesting/informative post.
Well done
Pep
Hey Pep - Welcome brother! Glad you made it back, and Happy New Year!.
I saved a lot of my old posts over the years "just in case" - well, glad i did.
Having your own homegrown Chilton Shop/Auto Repair Manuals is nice. >grin<
Wow, missed this one. Well done Ray, I appreciate this one!