Radial pin

I would guess that the pin you have is the actual radial pin. It would be difficult to tell the difference between 7.5 and 7.6 tpi. The fake radial is 8 tpi.
 
Tommy-D said:
The real Radial is either 7.634 or 7.637 TPI,NOT 7.5.

The difference between that and an 8 TPI is .006 difference in the width of the cutter,which is .1309 for the real one and .125 for the 8 TPI version,with a perfect 1/2 ball radius. With this small of a difference,you need a light and magnifier to see it.

If you good with a lathe,and have a nice lathe and put the grinder time in to make an 1/8 inch radius single-point tool,you can make the pin AND the tap yourself,because most lathes have an 8 TPI setting. ONLY CNC can do the 7.637.

I saw a new low-end Lucasi or Action cue here in town with the 8 TPI version in it.

The quality of the fit with whatever tooling they used was as nice as I've EVER seen anyone put out with the real Radial,with no exaggeration.

Personally I like the real Radial,except in G-10. I've never heard of anyone constantly having to check the tightness of the facings with a metal Radial,but it seems like the G-10 stretches a couple thousandths or something. Tommy D.
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Actually, my Myford lathe can cut the Radial thread pitch, to the samples I have. I am not measuring the same tpi that you are quoting, nor am I getting the same radius for the form cutter, unless there is something I am missing here.
I have 2 taps, a standard, and the undersize tap.
They both have the same pitch as each other,The pins came from Atlas and I have to assume they are the genuine article.

I put them up on the shadow graph and measure the pitch as being 3.344mm , over 5 pitches measured 16.72mm. 7.595tpi
The tap looked to have a radius of 1.984mm but the pin looks to have a radius of 2.00 mm

From taping a piece of wood and then trying to measure the pitch from the screw , I get pitch readings of 3.32mm. 7.65 tpi

I am thinking that the nominal pitch is actually 7.6tpi,
16.71mm over 5 pitches, this is inside the tolerance of manufacturing, and a 2mm radius insert is used as the threading tool, then the pins are electro polished.
Neil
 
rhncue said:
True. But then every pin used in cue building except 5/16-18 are bastard screws!

Dick
Click to expand...

You are right, of course,..... but, why is that????

the 3/8-10 is an actual acme thread
3/8-14 is a somewhat common thread


why the need to make these odd threads................. I don't understand it

remember Sears did that with all their tools..... it cost them sales and they went standard after a while

Kim
 
whammo57 said:
You are right, of course,..... but, why is that????

the 3/8-10 is an actual acme thread
3/8-14 is a somewhat common thread


why the need to make these odd threads................. I don't understand it

remember Sears did that with all their tools..... it cost them sales and they went standard after a while

Kim
Click to expand...

The 3/8-10 that is commonly used in cues is not an acme thread. It's a standard v groove thread, and quite different than the 3/8-10 acme thread.

Royce
 
whammo57 said:
You are right, of course,..... but, why is that????

the 3/8-10 is an actual acme thread
3/8-14 is a somewhat common thread


why the need to make these odd threads................. I don't understand it

remember Sears did that with all their tools..... it cost them sales and they went standard after a while

Kim
Click to expand...

3/8 16 UNC
3/8 24 IS UNF
Go to a hardware store and ask for 3/8 10 , they have no clue.

Now, how many VARIETIES of 3/8 10 are there out there ???
.290-.295 minor ?
.305-.308 flat minor ?
How many kinds of taps ?
3/8 10 is not only a bastard thread, it's been bastardized a few times already.
In fact, it's more bastard than the radial.
Everyone now pretty much gets his radial from Atlas,Unique, Prather or TNS directly.
They all mate fine afaik with the radial undersized tap.

Meanwhile I've seen shafts on 3/8 10 by hall of fame makers even wiggle at the ferrule end by A LOT before the faces meet .
 
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whammo57 said:
remember Sears did that with all their tools..... it cost them sales and they went standard after a while

Kim
Click to expand...

I'd be interested in hearing a little more about the Sears' tool thing.
I've been using Craftsman tools my entire working life.
I'm wondering if I missed something.

KJ
 
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