Help Tapping New Shaft for 3/8-10 Pin

GrimmCustomCues

GrimmCustomCues

AzB Silver Member
Silver Member
I was wondering if you all can give me some tips on Boring and Tapping a new shaft for a 3/8-10 Pin. I plan on experiementing with a few different methods and see which works best for me, on a bunch of wood dowels ofcourse.

Richard
 
GrimmCustomCues said:
I was wondering if you all can give me some tips on Boring and Tapping a new shaft for a 3/8-10 Pin. I plan on experiementing with a few different methods and see which works best for me, on a bunch of wood dowels ofcourse.

Richard
Click to expand...
I use a 3/16" end for a pilot then I use a 19/64 drill bit. I drill them 1.5" deep. his way I get a very good tight thread when I use 3/8x10. I also use a stuby drill bit..
 
Live threading will be a future option but right now Im not capable of doing it so Ill have to do it the old fashion way. Ive done a couple searches and I spend more time reading threads that have nothing to do with what Im looking for. Thanks for everyones input.

Richard
 
after your first tapping of the hole, fill it with cyano glue then fling it out. let it dry/cure completely then chase the hole again with the tap. This will help your threads last longer. For repairs later, you can bore out the hole and glue in a phenolic plug, then drill and tap the plug.
 
CuesRus1973 said:
after your first tapping of the hole, fill it with cyano glue then fling it out. let it dry/cure completely then chase the hole again with the tap. This will help your threads last longer. For repairs later, you can bore out the hole and glue in a phenolic plug, then drill and tap the plug.
Click to expand...

I like the cyano idea. What about the phenolic plug to start with? I know McDermott uses some sort of plastic plug in all their G-Core and I shafts.

Richard
 
If you don't use the phenolic plug, use an H0 class fit tap for the shaft to tap the wood. It will fit tighter and last longer. If you go ahead and use a phenolic plug, you don't need the H0 fit tap, the standard H2 will work. Don't use the H0 for installing the pin. Ever. It is slightly smaller and the pin will be too tight. If the glue expands your forearm will split.
 
Adding a phenolic plug changes the way the shaft plays so know what you want to accomplish.
 
Just curious, are you working with a regular 3/8X10 or a 3/8X10 flat bottom. Didn't see that mentioned anywhere. I've never had to do that super glue thing, I bore hole to .285 but I don't use the standard tap from Atlas, Just my opinion, there to big for the fit I want.
 
JoeyInCali said:
That should do the job.
Spot drill 1/4, bore to 5/16, lubricate, tap.
Click to expand...

Joey gave you the basics but given your level, you may need a little more of the in-depth specifics. After you learn what you're doing and why you're doing it, you can do it anyway you want.

Start by truing the shaft in the lathe and take a light face-cut to true the face to the center-line of the shaft.

Use a 7/16" center-drill to start your hole. You're going to want to go a little bit bigger than 3/8" on the dia. of the entrance to the hole so as to leave a small chamfer after the hole is tapped. This will be the true center of the shaft and that chamfer will allow you to always get back to center.

Apparently there are several size tap-drills you can use for the 3/8x10 tap.
In my work/job, I use a 5/16" drill because I don't know which style of 3/8x10 pin the shaft I'm building will go on. 5/16" hole will go on both.
Anyway, drill your hole to your preferred depth, usually 1/4-3/8" deeper than the length of the pin.
This might be a good opportunity to check your lathe. Once your hole is drilled, measure the id. The amount that it is over .3125" is twice the amount your tail-stock is off to the head-stock. You don't have to do this every hole. Just every once in a while to check.

I tap under power so this may not apply to you.
I use candle wax on the tap. Mark your tap so you know where to stop.
I tap to 1/2 depth under power and stop, manually back out the tap, clean out the hole, clean the tap & re-wax.
Manually start the tap back in the hole then finish tapping under power to depth (your mark) and stop. I then manually remove the tap from the hole.
Clean-out the hole, clean the tap, put your toys away. You're done.

Once you start doing ring-work, this is the time to do it, before you take the shaft out of the lathe. Everything so far is centered and true. Doing the rings now insures that they will be true to the hole as well.
Once you have the rings installed, you can now remove the shaft from the lathe and let the epoxy cure. For me, the shaft goes right into a bar-clamp to hold the rings in place and under light pressure.
Now your lathe is freed-up and you can start the next one.
After 8 hrs or so (preferably more) I can put my shaft back in the lathe using the live center in the tail-stock supporting the jnt. of the shaft via the chamfer I put in and trim the rings to the size I want.

It may be more than you wanted to hear but by the same token, there may be something there you can use.
Good Luck.
 
Last edited:
Michael Webb said:
Just curious, are you working with a regular 3/8X10 or a 3/8X10 flat bottom. Didn't see that mentioned anywhere. I've never had to do that super glue thing, I bore hole to .285 but I don't use the standard tap from Atlas, Just my opinion, there to big for the fit I want.
Click to expand...

I was going to start with the standard 3/8-10 1st and maybe try the flat later. There's different sizes of 3/8-10 taps?


Richard
 
KJ Cues said:
Joey gave you the basics but given your level, you may need a little more of the in-depth specifics. After you learn what you're doing and why you're doing it, you can do it anyway you want.

Start by truing the shaft in the lathe and take a light face-cut to true the face to the center-line of the shaft.

Use a 7/16" center-drill to start your hole. You're going to want to go a little bit bigger than 3/8" on the dia. of the entrance to the hole so as to leave a small chamfer after the hole is tapped. This will be the true center of the shaft and that chamfer will allow you to always get back to center.

Apparently there are several size tap-drills you can use for the 3/8x10 tap.
In my work/job, I use a 5/16" drill because I don't know which style of 3/8x10 pin the shaft I'm building will go on. 5/16" hole will go on both.
Anyway, drill your hole to your preferred depth, usually 1/4-3/8" deeper than the length of the pin.
This might be a good opportunity to check your lathe. Once your hole is drilled, measure the id. The amount that it is over .3125" is twice the amount your tail-stock is off to the head-stock. You don't have to do this every hole. Just every once in a while to check.

I tap under power so this may not apply to you.
I use candle wax on the tap. Mark your tap so you know where to stop.
I tap to 1/2 depth under power and stop, manually back out the tap, clean out the hole, clean the tap & re-wax.
Manually start the tap back in the hole then finish tapping under power to depth (your mark) and stop. I then manually remove the tap from the hole.
Clean-out the hole, clean the tap, put your toys away. You're done.

Once you start doing ring-work, this is the time to do it, before you take the shaft out of the lathe. Everything so far is centered and true. Doing the rings now insures that they will be true to the hole as well.
Once you have the rings installed, you can now remove the shaft from the lathe and let the epoxy cure. For me, the shaft goes right into a bar-clamp to hold the rings in place and under light pressure.
Now your lathe is freed-up and you can start the next one.
After 8 hrs or so (preferably more) I can put my shaft back in the lathe using the live center in the tail-stock supporting the jnt. of the shaft via the chamfer I put in and trim the rings to the size I want.

It may be more than you wanted to hear but by the same token, there may be something there you can use.
Good Luck.
Click to expand...

Thanks KJ for taking the time to give me the step by step process to do this. Im going to be busy practicing this for awhile before I ever touch a real shaft.

Richard
 
GrimmCustomCues said:
I was going to start with the standard 3/8-10 1st and maybe try the flat later. There's different sizes of 3/8-10 taps?


Richard
Click to expand...


Hi Richard
Yes, there are different size taps, I have 4 taps just for 3/8X10. I had mine made by North American tap and die but I believe Atlas sell different size taps. The regular thread 3/8X10 for example, you can use a smaller drill than 5/16 because the pitch of the screw depending on who made it can go as low as .281 The screws that Schmelke sells, the pitch is not as deep, so I am guessing that they adjusted for the slop of the standard tap. The flat bottom I have not worked with but I believe you need at least a .304 or .306 hole so the 5/16 hole should be okay. I hope some of this helps you.
 
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