Cutting a 6-44 screw

[Jack F]

I have a need to cut a 6-44 screw. I need it for one of my indexable lathe tool holders as the existing screw is too short for the carbide cutter I have. I have tried the local specialty screw dealers and local machine shop supplyers with no luck. What I need to know is the cutter for that tight a thread 60 degrees and what type of cutter should I be using. I havn't tried to look for a die yet as I feel I would have the same luck as with the screws. Thanks for any help.

[RICHARD ZASTROW]

Jack, I'd like to help but I can't find anything on a 6-44 thread. The closest thing is a #5-44 in Machinery's Handbook. Unified extra-fine chart starts at #12-32. There may be a #6-44 UNEF tool out there somewhere, but I bet it's a special order.

[lerman]

What makes you think it is a 6-44 thread? 5-44 and 6-40 are both standard sizes. As far as I can tell, 6-44 is NOT a standard size.

At any rate, if you look at the screw you have under a magnifier, you will probably find that it does have a standard 60 degree form. Machinery's Handbook does have a section that will tell you how to compute the various aspects of the thread form -- if it is a standard form.

If I were you, I would first try 5-44 and 6-40 screws.

Ken

[ajl6549]

Who made the tool holder your making the screw for?

[jetski]

could it be metric? hey hey quit thowing stuf at me. I was just asking! because it is close to being a .5 mm lead. You guys throw like girls. Just kidding. Ok who hit me with the rotten egg that said union rules on it. I guess all I am saying is depending on the age of the machine it may have some metric threads on it. Or the tool holders may have been made over seas. I run it to it quite offten. Ok thats it who hit me with the tomato. I am out a here.

[Jack F]

Thanks guys. I tried a 5-44 screw and it goes in OK but it is loose. I tried a 6-40 screw and it started but bound up right away so I think it is a 6-44. I went to a gunsmithing site and found some 6-48 screws. I will check my thread guage again to the existing good screw and see if the 48 thread guage fits. I would buy a die but I only need 1 screw and hate to shell out $14/15 for 1 screw (I know, I'm a tight wad). The only indication of a brand is "R.B." and it is stamped "Made in Germany". Jetski, it wasn't me throwing things, I've got a bad arm throw anything. I guess I threw too many rocks as a kid.

[kiwichris]

Originally Posted by Jack F of a brand is "R.B." and it is stamped "Made in Germany". Jetski, it wasn't me throwing things, I've got a bad arm throw anything. I guess I threw too many rocks as a kid.

"Made in Germany" That's pretty close to France (compared to the US), it could well be metric...

[eject_21]

try a M3.5 X 0.6

[Jack F]

Thanks guys. One of the specialty screw stores thought it might be a m3.5 but he didn't carry any. Tried another screw store....they didn't carry them either. Tried on line... same story, so I guess I will have to make one. Anyone have any pointers on turning a screw with this tight a thread? I will most likely turn down a larger hardened screw then do the threading on it. Thanks again, Jack.

[RICHARD ZASTROW]

Jack, Ever heard of a 1/8(3.175mm) -44? Its a "sewing machine" thread.

[kiwichris]

It's not just a standard M4 is it? the lead is .7mm.. 6/44 would be 4.233 / 0.577.

(edit: having trouble believing that something german made would have an odd, non-standard thread it it...)

[eject_21]

what type of screw is it? micro fasteners have a few in M3.5 X.6 They have pan head and shcs that size, 8mm long. You dont have any unused equipment hanging around? We had an old, dead mori lathe that was a treasure chest of hard to find, odd sized screws.You may want to look in an old desk top computer, would sure be easier than turning one. especially if your unsure of the size.