Broaching (ha ha) a new topic

[Cutman]

 Hi all,

Just learning about how they make my famous unable to find PWA 3267 socket. It's for a 24 spline nut, and I was curious how it was made.

Turns out there's a machining process called broaching, which cuts the inside of a tool steel blank. Anyone here ever do anything like that? Just curious

Best, John

[Papaw]

Broaching was the method that moved socket design from the old way like Mossberg and others.

[oldgoaly]

I make square holes in steel pegs! made my own Pullmax collets. Plus have broached a number of keyways in bead roller dies. go slow and easy as not to break anything!

[gibsontool]

Broaching is a very common task in machine shops, one example is cutting a keyway inside a sprocket.

[Cutman]

 Do you think it would be expensive to have an inch and a quarter 24 point spline socket made up?

[lptools]

I have no idea of the cost, but the bulk of the expense would be in the planning & set-up. Cost per socket would likely go down if you made more than one. Do you know anyone with a similar interest? Pool your resources? Just a thought, Lou

[Chillylulu]

Do you think it would be expensive to have an inch and a quarter 24 point spline socket made up?

1¼" to the outside of the splines?
Can you show a picture of the fastener?

Chilly

[leg17]

I would expect the broach to cost around $500-1,000, give or take.
Then you need a suitable broaching machine and a properly designed blank socket.
You need to check with a broaching company for more precise estimates.

How many sockets of that exact size are you wanting?

[Nolatoolguy]

It would be costly to broach a socket blank 24 spline socket. It’s do able but costly, specially for one socket.

My work is always making their own specialty tools. Lots of our work is one off rush jobs for the energy industry. For socket type things we have cnc waterjet cut the shape an welded onto Whatever handle or ratchet need be. Other tools we can do up to 5 axis milling on. It’s not a pretty looking tool but works in a pinch. We also do convential broaching but a 24 spline socket would be easier to do in cnc.

[JoeCB]

When someone asks about having something made, the first and MOST important question is ... how many do you want? The answer drives the degree of capitalization required for the job. Want one, very low capital investment and perhaps lots of labor. If you want 10,000 the capital investment could be substantial, labor for actual production nearly zero.
As for your 24 pt socket, need only one? no expensive broach needed, the job can be done on a shaper, tooling cost about zero.

Joe B

[johnsironsanctuary]

One way to approach the problem would be to find something that has that spline already cut. A trip to the local driveshaft repair shop might find a yolk with that spline. If I were making one, I would look into wire EDM. That would only require a cad drawing of the spline and paying for the machine time. No tooling. A wire EDM looks kinda like a band saw, but the wire has an electrical charge that removes metal by reverse welding metal from the part to make a kerf. Very precise!

[leg17]

..... If I were making one, I would look into wire EDM. That would only require a cad drawing of the spline and paying for the machine time. No tooling. A wire EDM looks kinda like a band saw, but the wire has an electrical charge that removes metal by reverse welding metal from the part to make a kerf. Very precise!

Likely to cost $500, if you can find a shop sympathetic to interrupting for a one-off job.
And, since the wire goes all the way through, would the socket drive end have to be made separately and welded on?

[Cutman]

Thanks all for the interesting contributions.  It's as I thought, doing 1 is expensive, doing 500 is cheap.

I wish I could find other folks that need it, but it's a pretty rare user anyway.

FWIW the fastener looks like a gear welded onto a stud.

I broke down and paid $140 for the appropriate socket from Kell-Strom.  Nasty cost but tit is a new socket so they probably ran some off recently.

Thanks again for all the info.

Best, Cutman

[leg17]

Cutman
Thanks for the follow-up.
You made the right call.
The price factor will fade away with time and you will still have the best solution.

[Nolatoolguy]

Thanks all for the interesting contributions.  It's as I thought, doing 1 is expensive, doing 500 is cheap.

I wish I could find other folks that need it, but it's a pretty rare user anyway.

FWIW the fastener looks like a gear welded onto a stud.

I broke down and paid $140 for the appropriate socket from Kell-Strom.  Nasty cost but tit is a new socket so they probably ran some off recently.

Thanks again for all the info.

Best, Cutman

I would of guessed more for a specialty tool like that. It’s not cheap but no specialty Tool is.