Feeding the addiction!

[oldcarguy]

My friend relayed the blade dimensions for the Brown & Sharpe 496. It's .062" by .635... That's within a few thousands of my Stiefelmayer blade, @ (.068" by .632").

Do you wish that I make both a 12" and 6" blades for you? I will then order the stock

[Uncle Buck]

Absolutely, I would be foolish not to! Advise as to cost of material. Can I pay for material with PayPal?

[Uncle Buck]

My friend relayed the blade dimensions for the Brown & Sharpe 496. It's .062" by .635... That's within a few thousands of my Stiefelmayer blade, @ (.068" by .632").

Do you wish that I make both a 12" and 6" blades for you? I will then order the stock

I thought the depth of the groove would also be critical  as well as confirmation that it sits dead center on the blade too.

[oldcarguy]

The groove in the blade on My Stiefelmayer is off center by .008”. And locks in place either way the blade is inserted int the head. The groove in the B&S 496 that I'm using as an example is .006 off center too. I bet there's some leeway of the location of the groove and the width for that matter..

The smaller of the two knurled locking screws has a cam on the underside. When rotated a tab on the underside catches the edge of the groove of the blade. Locking it into place on the head. Either direction will lock it. The depth of the groove is not important. It's simply clearance for a small locking tab. I wouldn't be surprised that the Stiefelmayer blade would work with the B&S head...

In any event I will check to see if the blades a interchangeable.

The protractor really has some marvelous engineering put into it.... 

[Uncle Buck]

Your thoughts on interchangeability I absolutely suspected myself, though my hunch was simply based on the appearance of blades in pictures.  Regarding the groove,  I was clueless and thought the depth would be critical.  Starrett blades are a much different animal in that the groove is offset and clearly nowhere near the center of the blade. Additionally both ends of their blade are not opposed like every other I saw, but instead angled the same way. On an unrelated note, this type of protractor instrument must not have been one of Lufkins product offerings because I never found even one example which struck me as odd.

[Uncle Buck]

I find the beauty of this style instrument nothing short of a work of art. Honestly,  I am not terribly worried if I ever put it to use! That would be nice, but not one of my conditions for owning the tool. I do want it functional and accurate as much as possible like every other tool I own. That said, simply the love of the tool and its beauty alone could never justify heavy investment, but at a more modest figure it more than satisfies me.

Surprising how many folks there are trying to sell bladeless versions of this tool in various brands at great cost. I knew due to researching prior to purchase that even with ebay, blades would be tough to find used, and quite costly new so making blades would need to be seriously considered. A cheap import might have been robbed of its blades and case and might have worked, however it would likely have been a very long time before I would have ever seriously considered that an option for me. OCG offering to make the blades is more than I ever expected as the answer to  my dilemma.  Like GF said, the blades he makes will likely be better quality than what could have been sourced from B & S when the tool was new!

[oldcarguy]

I'm doing some testing. I cut off a foot from a from a piece of .190" by 1" cold rolled steel i had hanging around. As you can see it's bent. There's always issues when grinding thin pieces of steel. The power of the magnetic chuck will draw the work piece down. And the final result the piece will wrap back. The stock will be parallel. But not flat.

One needs to shim the piece and take the high spots off. Then flip it over, shim, and take the high spots off. After five flips, it came out both parallel and flat.. The stock started at .190" and not it's now .140"..

The other option is to place the work piece at 45 degrees on the chuck if it's still wrapped.

My grinder has a very strong fine pole permanent magnet. And hold smaller pieces better.. And has a great supply of coolant to keep the work from heating up.. Did I ever mention that I really like my surface grinder


Before..




Finished ground...

Flip side...



 

[Uncle Buck]

I have only had one experience operating a surface grinder. Looking back, I wish I had practiced on several scrap pieces of material to get a feel for using the machine before trashing my final project for the class, a tool makers vise. Sadly, after destroying the vise not enough time remained in the semester to make another. I do recall it did not take many passes under that grinding wheel to trash my parts! Lesson learned. I feel more at home on a lathe, mill, and a shaper.

[oldcarguy]

The surface grinder was always my favorite machine to run. Like any piece of equipment. You need to learn to respect it, and understand its' capabilities. Precision vises are a great accessory to have and makes holding work pieces easy. Here's a few that I was able to make over the years. I was a mere fourteen years old on this one. It's made of O-1 oil hardening tool steel hardened to 60 RC. This design is far more difficult to make; but has its' advantage in use. Note the two piece screw design,, the smaller on is a LH thread. While the bigger one is RH. Turning the handle moves the jaw twice the distance, yet a stronger holding power than a coarser thread... And has a nice flip up "speed Lever" added to the knob...





All the other are made from low carbon steel and case hardened. Called Nitriding Where Nitrogen is diffussed into the surface making it 70 RC. . Leaving the core soft and more stable.  Baby one, And a sine vise.. All are still within tenths of being square.

[Elroy]

that little flip down speeder handle is neat.

[Uncle Buck]

Those are some incredible vises you made for sure, especially that first one you showed. I have never seen another vise of that design.

[oldcarguy]

Thanks for your compliment. You'd be hard pressed to find a grinding vise made like mine is. And with few if any examples 60 years ago. I studied stanard machine vises of the day and took it from there.  A lot of thought was put into building them.. I have two of them and both are four inches across the jaw.   The underside shows the way the movable jaw is kept true. There's a tongue below the jaw surface that runs in a channel of the main frame. That was a real trick to grind a 3/4" wide slot. A small die grinder was mounted on the spindle of an old Hammond 6" by 18" hand surface grinder. The double thread idea does two things. The jaw moves twice as far per rotation of the screw. Plus there's half the amount of screw travel out the end. Making a shorted overall length.



Here's a few more of my home made vises. These were styled after the Suburban Tool designs, made 50 years ago. Far less amount of work needed to compete. Three inch and two inch size.



Here's a small sine bar,, 5" centers



compound sine plates both have five inch centers.. Six by six inches









   

[Elroy]

Elroy would call that 4140 ideal if the rule had to be thinned. a prehard stock near size would be real good. maybe an air hard A2

[oldcarguy]

I am narrowing it down to pre-hard 4140 about 28 to 30 RC. Air Hardening A2 is too soft in the annealed state and I don't care to get into heat treating. You never know how wrapped it would be afterwards.   

[oldcarguy]

I just return from picking up the flat ground stock for the blade. Being 18" long, I plan on cutting the two blade, One 6" and one 12", from this 18" piece. I'll cut it at 45 degree angle to make each a tad longer longer then stated 12" and 6" lengths. The stock is .093 thick by .750 wide. I'll have to remove 1/8" from the width. And have .030 stock to remove from the thickness.

I ordered a 4140 stock, and the paper work indicates that. But as you can see the package indicates it 4142.. Most circles claim they're one of the same. The 4142 has a bit more carbon. Giving the steel a few points harder. Not an issue in my book...