Thread: Did I lose temper on this blade?

I'm new to restoration; any help would be appreciated. The picture below shows my blade after it's been run across my buffing wheel during first phase—using 80 grit grease-less compound. I paused as soon as I saw that part of my blade was reflecting the buffing-scratches differently. I'm unsure if this part of the blade has just been buffed more than the rest, or, is this temper loss causing color change. It was very hard to get a photo of the area that looks discolored; look closely where there's a faint white circle. Is this what overheating looks like? I'm using 4" cotton sewn wheels with a 3450 rpm machine; I am aware that this rpm can heat a blade quickly. Thanks for any help.

It's hard to tell from the photo, but I doubt it. In general overheating is indicated by various darker shades of blue/gray/black. Regardless of the state of this razor, when you are buffing the blade should never be allowed to reaching a temperature that is hot to the touch. Keep it cool! Watch the pressure--the more pressure you apply, the faster the blade gets hot.

That look more you have a more even scratch pattern there to me
The thinner part of the blade heat way quicker than the part you are conserned about

Heat discoloration happen after the temper is ruined so lack of it doesnt mean you are safe.

Im actually more conserned about the hue you have closer to the edge

I usually se it as shades of brown and blue

Unrelated to the temper: If those scratches are from your buffer, try using less pressure in the future.

Another possible answer is that the blade is harder at the edge and softer at the spine. This would allow the cutting grit of the polishing to move more material where the blade was softer. But it doesn't have the expected features of lost temper due to polishing.

To lose temper, don't you have to heat the steel to more than 150C? Wouldn't you burn yourself way before you reached any danger to the steel?

Originally Posted by janivar123

The thinner part of the blade heat way quicker than the part you are conserned about

Heat discoloration happen after the temper is ruined so lack of it doesnt mean you are safe.

Both are critical points I failed to point out.

Originally Posted by HNSB

Unrelated to the temper: If those scratches are from your buffer, try using less pressure in the future.

Personally, I don't see anything wrong with those scratches given that they are from 80 grit compound.

Originally Posted by JimR

To lose temper, don't you have to heat the steel to more than 150C? Wouldn't you burn yourself way before you reached any danger to the steel?

As was already pointed out, the thin edge heats much more quickly. By the time you feel the heat in the tang and spine, where you might be holding it, the temperature at the edge already could be too hot. Just overheating one small area can still trash the whole blade.

What you are seeing there does not appear to be related to heat.

If you are using the buffer correctly, which is to say that the wheel is moving in a direction off of and away from the cutting edge of the blade, then what often happens is that due to the radius of the buffing wheel being larger than the radius of the hollowing in the razor blade a lot of the buffing compound is deposited in that upper area between spine and middle of the razor blade where the fibers of the wheel do not make full, clean contact with the metal of the blade.

It is also so that the wheel will fail to do its buffing work properly here if the radius of said buffing wheel is too great relative to the hollowing of the blade, since the wheel is not really contacting the blade properly at that point.

I've included an illustration of the relative contact points between buffing wheels of three inch diameter and two inch diameter relative to a 5/8 razor blank. The red area represents where the outer diameter of the wheel(s) fails to meet the hollowing of the blade. Even though the buffing wheels have an amount of 'give', they still can't always be pushed in close enough to allow the fibers of the wheel to eliminate that gap.

The best cure for this is using smaller diameter wheels, just as were used during the production of the razors at the factory.

Although this would seem to suggest using a small, hand held rotary tool, the truth is that at the factory very small diameter wheels are used on fairly beefy, high speed, stationary buffing motors using pigtail mounts. (see photo)

Here is a good thread to look at for buffing...

http://straightrazorpalace.com/works...-question.html

See the way I hold my finger along the back edge of the blade???
This not only is safer, it is an tell-tale for heat build up...

Thanks for the replies. I continued with each compound (finishing at 600), and used a couple Formax polishing compounds: White Lightning Rouge, and Red Rouge. I think I'm missing a couple compounds because the razor—as you can see—still has thin buff-scratches all over it. Do I need a Stainless or Tripoli compound to remove these? Thanks.