When I bought this at the little antique mall I frequent, I thought it was just the regular PH screwdriver.  In the process of cleaning it I noticed that the tip was different.  It didn't have a number on it like most of them, rather there were 'wavey' impressions on the tip that it is wider and shorter than most.

The only other one I've seen with impressions on the tip had what I would call a chevron pattern and it was patented.

The only patent date on this one was for the handle.  Anybody seen this type before?

Mike

That looks like file marks on the tip to me and thats all i have to say.


EvilDr235

I am sure it was first abused, and then someone took a very coarse file to the tip.
The tip is not a regular tip for any screwdriver.
The double tapered standard shape was proven to be the strongest pattern over and over. And people were used to seeing the profile of it, so it sold in the marketplace. 
Everybody used it in manufacturing.

I have reforged lots of PH screwdriver tips. Even the big ones can be done with 2 ordinary propane torches and practice.
  The big ones are faster and easier with a hotter torch, but that's ok, you can still do them. And the med and small ones are closer to a piece of cake. 

  Set up 2 torches facing each other, and make a vortex of heat.
Whatever you hold in that vortex heats up.
   Its 3 times faster heating both sides at once, compared to a single torch.   

Here is another quick tip
Set up a one burner propane camp stove. Throw your driver on that running full blast, while you futz around setting up your torches, hammer, anvil, quench can, etc. 

Preheat your work.  Saves time when you do go to heating it for real.
      yours Scott

Scott,

How hot do you take that tip when hardening? How high up the shaft do you take the hardness?

Sincerely,

Chilly

Quote from: Chillylulu on December 26, 2014, 06:35:43 PM
Scott,

How hot do you take that tip when hardening? How high up the shaft do you take the hardness?

Sincerely,

Chilly

As much as you can.

Heat up as much steel as you can to cherry red, and plunge it in oil.
Plunge it outside phew
Obviously, the little ones you can about do the whole shaft.
Big ones take forever to heat in ordinary household propane. Even with two bottles going. So heat as much of it as you can. You'll get a good chunk of the end anyway.

  The handle part? That was always soft and should remain soft. I wouldn't bother to heat the handle frame. There is no bonus in it.

After you harden it you have to temper it and its not really even temper you want this time. You want to run the color toward the tip and stop just the tip at slightly higher hardness.
The rest is softer. Spring temper, about 600 degrees.
  Blue temper it blue. The main is blue while the tip is brown with purple spots.
  I know that sounds insane but its true. Brown with purple spots.
  I tried to take pictures of it one time.   
http://www.wkfinetools.com/tRestore/techniques/heatTemper/heatTemper1.asp
      yours Scott

Scott,

Thanks for the link. That was perfect.  I've tempered cutting tools before. I helped a group of Boy Scouts make punches from scratch. But I haven't ever hardened a screwdriver.

I have half a dozen perfect handle types that have either a badly damaged tip or missing or messed up scales. They are up there on my list, right after I finish some remodel work on my house and finish re-working / cleaning my garage.

Larry