After my experience threading 1/4 inch aluminum rod to M6x1.0, I am sure 5/16 rod is just enough undersize for an M8x1.0, M8x1.25, or even M8x1.50 die stock to thread in a really sweet way. I'm trying it tomorrow.
Cheers,
Douglas (Dana) Goncz Experimental Machinist Replikon Research Seven Corners, VA 22044-0394
Correct, although I question the use of 1/4" material for 6MM threads. It's woefully oversized.
Harold
Harold sez:
"Correct, although I question the use of 1/4" material for 6MM threads. It's woefully oversized."
Harold,
Why'nt you just tell him the quick and dirty way to size taps drills for metric is: Drill diameter = Metric size - pitch in mm.
Bob Swinney
Oooppps ! To size rods for external metric threading: Nominal Diameter - (pitch X .866)
Bob Swinney
Oooopps! Wrong again - just wanted to see if you were awake. The rod size for metric threading is: Nominal diameter - (.125 X Cos 30 degrees) X pitch in mm.
Bob (shamefully bowing head) Swinney
Chuckle!
H
message
Of course you question it. I didn't make it clear. I didn't mention I filed the 1/4 inch rod to 0.234 inches minus a few mils. It threaded OK then, but I was looked for a rod that could be threaded with nearly no preparation.
The point I was trying to make was that M6 is *smaller* than 1/4 inch so turing or filing is mandatory. M8 is *bigger* than 5/16, so I tried it and the threads were beautiful. Most of them were sharp-V on the eyball inspector gage. :)
Let's see, the next size up is 3/8 inch, and M10 is 0.390. It's bigger than the inch size. Might work.
So, 1/4 inch rod is too big to thread M6. 5/16 in aluminum rod threds to M8 OK. and 3/8 inch rod might thread M10.
That summary is what I wanted to establish. Now to stock up on 5/16 inch aluminum rod through Amazon while my Prime subscription is still active. Small parts, $2.56 per 6 foot length, no shipping because of the Prime trial. Whee!
1/4 and 3/8 I buy at Hoooooome Depot, nearby, the hottest pick-up spot in No. Va. Every Friday and Saturday evening you'll see couple in the hardware aisle having conversations like, "I just met you but I need a good screw." :) *I'm not kidding, they are everywhere!*Doug
See what your local welding supplier stocks or will order for TIG rod. The largest I've found is 1/4" but they had a good variety of smaller sizes like 3/16" and 5/32" which can be threaded #10 and #8, or 5mm and 4mm.
jsw
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