Inside threading, can you recommend some tooling?

If I were to get something like a SNR0010K11 that is a RH tool, and I'd flip it upside down and reverse the lathe? Can one get an insert that would work for grooving as well? Would like to have a thread start area. Or have I got it all backwards? This confuses me, a lot! I could go up to 12mm, or a SNR0012K11. Is this ok? SNR0012K11 & Inserts
 
Yes that one looks good, and LMS has a good return policy if it doesn't work out for you
I've seen some inexpensive stuff on Aliexpress also, if you can wait a month
-M
 
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I can wait, did I say that? Yeah, I could wait. Don't want to, but I can wait. Is the snr0012k11 style reasonable for my intended use?

Only issue with the LMS item is the minimum bore size is 1.375". Was hoping to make this be 1.25", but 1-3/8 is ok. And yeah, it is $109.
 
This just is calling out for high speed steel hand ground tool bit. For a few dollar piece of steel and a little time on a grinder you can have something that will work for a one off item. I have even taken a broken tap and ground one down so the remaining tooth is the cutting bit. Cost is little and I learned some along the way.
 
How about this: make a small boring bar by drilling a hole to hold an 1/8" square HSS cutter. Drill & tap a hole for the set screw into the end of the bar. Grind the HSS to a 60* form, lock in bar with set screw. Do the form grind before cutting the bit free so you have something to hang on to. You can grind another piece of HSS to use for a start groove. Run the lathe so you can cut from the inside toward the outside. For an internal thread the bar is mounted parallel to the ways. Doesn't matter what angle the compound is at since it isn't used, just lock it. It might be worth making a good rest for your bench grinder. If the grinder is mounted to your bench you can make a rest that bolts to the bench top rather than to the grinder. Make it adjustable in all directions/tilt and put a slot for a tool holder to slide in.
 
How about this: make a small boring bar by drilling a hole to hold an 1/8" square HSS cutter. Drill & tap a hole for the set screw into the end of the bar. Grind the HSS to a 60* form, lock in bar with set screw. Do the form grind before cutting the bit free so you have something to hang on to. You can grind another piece of HSS to use for a start groove. Run the lathe so you can cut from the inside toward the outside. For an internal thread the bar is mounted parallel to the ways. Doesn't matter what angle the compound is at since it isn't used, just lock it. It might be worth making a good rest for your bench grinder. If the grinder is mounted to your bench you can make a rest that bolts to the bench top rather than to the grinder. Make it adjustable in all directions/tilt and put a slot for a tool holder to slide in.
This seems like a pretty good idea. I can make a little boring/grooving bar. Will order some 1/8" square HSS. Was looking at these kinds of bars, but didn't know how to make the square holes. Round hole, square HSS and a set screw seem like a good alternative.

Been toying with making a grinding rest. When I first looked at some plans, 2 years ago, I wasn't capable of making one. Just didn't have the skills. Think it's possible to do now.
 
I was going to suggest making something- wasn't sure if you were comfortable with that.
I actually made a fishhook tool out of a large nail once, and hardened it with my propane torch.
Worked fine for a couple threads in aluminum
-Mark
 
Keep in mind that that Arthur Warner threading tool has a minimum internal bore diameter of 1.375". Arthur Warner also offers lay-down style tools that work in a smaller diameter bores. I have both. I think the lay-down style lacks rigidity. My opinion is to stay away from the AW internal threading tools. Otherwise, the AW tools are great and the company is excellent.
 
I use Joe Pie method and use LH boring bar style holder like this one. That size will get you down to 1/2" thread. I use LH micro 100 carbide for smaller sizes. When you use the LH tool, your on backside of hole and running spindle in reverse. You can set your zero (tool bumps in hole) with lathe off and thread out. You can get pretty small with the micro 100 but usually better to use a tap when you get that small.
 
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