Rescale #2..Drat and darn!

[Toff]

Hi folks,
I learned a bit more this time. Like "do check the quality of the blade's steel" before going to the hassle of making a fresh set of scales incorporating all that you felt was missing in the last set you made. Duh!:cry: :thumbdown:

The end of the blade was the culprit. I did notice some amount of fine chipping and thought it would hone out later. Nope!!! I would suggest that one would hone the blade to at least 4K before expending serious effort. This was a 1830s Fenney wedge. A friend told me that some of the older steels seem to have a hard skin like case hardening and when that has been honed through there is no strength left to support a razor edge.
I hope this can save a good amount of work for some one.
Respectfully
~Richard

 

[Smythe]

Well you know I tell you what, I am afflicted with the Razor Restorer’s Disease.
In all my restoration work, only once have I test-shaved a razor before restoring it. As a result, I have quite a few razors that don’t shave well because of bad steel.
Not in any way suggesting it’s the right thing to do… it’s just me... call me stubborn for wanting to do things the hard way…
But I get a lot of practice restoring razors and discover some interesting things about them when finished. I have grown to like surprises… even bad ones.

As for the steel, you may be correct about case hardening… I read in an old book how they added carbon to iron bars to be used to make cutlery or tool steel.
They would place the iron bars along with old leather in an iron box (or pot) and seal the box from air. Then heat the whole to red heat and hold the temperature for a given time depending on the thickness of the iron bars.
The old leather supplies the carbon, but Iron will absorb carbon at a set rate, so the thicker the Iron bars, the longer it must stay in the pot at red heat... or the inner core of the bars wont get enough carbon and then they would end up only case hardened.

It is likely they miss-judged the amount of leather added to the pot or the time the bars stayed at red heat.

 

[danjared]

Smythe: Is this for pre-Bessemer process steel?

 

[Smythe]

I suspect so... I am trying to find that book (google books). It's a very old book (tool making?) and I just read it a few weeks ago and forgot to book-mark the page.

Incidentally several other texts will describe the same process for case hardening, but the book I read gave detailed instructions and heat times for thickness of the iron... I will find it.

 

[Toff]

That was a good, simplified, statement of the pack hardening process, Thank you!
Leather, bone meal, were all admixtures.

A useful book about "Pack Case Hardening" which contains a lot of other shop savvy is:
The Machinist's Second Bedside Reader and the Bullseye Mixture (Paperback)
by Guy Lautard

Publisher: Guy B E Lautard
Date of Publication: 1988
Binding: paperback
ISBN-10: 0969098030
ISBN-13: 9780969098034

For a razor restorer not so much, but for a home shop person a lot of information.
Respectfully
~Richard

 

[deighaingeal]

I have recently done something similar. I restored a blade then made and bolted the scales on. I then honed and shaved with it. This was NOS and shaved great. I then took it apart to properly pin it and I dropped the blade. I found a similarly sized blade in my lot and modified the scales to fit (I liked them scales) I then took the blade back apart to clean it up. Only then did I realize that the edge wasn't up to par. I still bolted it back into the scales, but after many rehonings I still haven't gotten a great edge on the thing, I really should stop trying.

 

[Toff]

I believed that there would be serious disruptions in plans when i got into razors. I felt not terribly forsaken when a trial went bad. I have a late 1800s W&B that someone did not really love somewhere along the line; heavy sand paper had been applied and scratches were found, a bunch.. So it is getting a regrind and fitted to the scales. I shall leave the grind lines on it to show that it has been reground.
More fun!
Respectfully
~Richard