Overheat issues, please HELP!!!

Hi Guys,

I just start in restoring old straight razors. Here a french blade A.Doupeux, that I wanted to polish with different grits. I do not have a grinder machine yet with coton wheels, I only had a "Dremel" with small wheels ...I could load easily the "Formax greasless compound 80 grit" It dryed prety perfectly on the small wheel.

Started with it...could not feel the heat of the blade because of my gloves...I guess next time I will not take protection gloves.

Everything went well at beginning...I have put the blade on a wood plate to be flat and secure.

After fininshing my second pass I found an overheat on the other side of the blade (not the side I worked, but the other side) Only on the bevel (all the bevel lengh)...here pictures.

Probably this would not happen if I would have used a grinder and not a small tool.

Now can you please tell me if there is a way to save the blade and how?? What would you suggest me? Should I through the blade away?

Thanks to let me know

ChrisAttachment 274266Attachment 274267

No don't throw the blade away I doubt if it's lost its temper, the trouble with the Dremel it spins far to fast creating heat and friction very quickly, if you can control the speed and be very aware and use it with a minimum amount of time your blade should be ok, ideally buy yourself a little bench polisher with a few mops, plus a few compounds varying from 300 grit grey sisal pre-finish compound green pre-polish then finally pink finishing polish.

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Originally Posted by celticcrusader

No don't throw the blade away I doubt if it's lost its temper, the trouble with the Dremel it spins far to fast creating heat and friction very quickly, if you can control the speed and be very aware and use it with a minimum amount of time your blade should be ok, ideally buy yourself a little bench polisher with a few mops, plus a few compounds varying from 300 grit grey sisal pre-finish compound green pre-polish then finally pink finishing polish.

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Thank you so much for answer...so what do I do now with it...I continu the job with a grinder trying to polish these black spots in the bevel? By the way what hapens when there is a real overheat on a blade, it will break, rust? we can't shave with it anymore?

One solution is to not use gloves, I don't and have never had problems.

Bigger wheels, no gloves, a foot pedal for controlling speed, all help. The bench buffer also will generate great amounts of heat and spoil a blade quickly. Any time I am using a bench buffer I keep water on hand to cool and lubricate the blade. I have no idea how much heat it takes to spoil a blade, but it is so thin I doubt it takes much. You should see if it will hold an edge before you put too much more time into it.

Use a piece of wood with a thoroughly soaked paper towel. The wet towel will absorb the heat.

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Originally Posted by rolodave

Use a piece of wood with a thoroughly soaked paper towel. The wet towel will absorb the heat.

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Ok I'll try that one...now what do I do with that one???? should I polish the "black part?

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Originally Posted by RezDog

Bigger wheels, no gloves, a foot pedal for controlling speed, all help. The bench buffer also will generate great amounts of heat and spoil a blade quickly. Any time I am using a bench buffer I keep water on hand to cool and lubricate the blade. I have no idea how much heat it takes to spoil a blade, but it is so thin I doubt it takes much. You should see if it will hold an edge before you put too much more time into it.

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Yes I plan to buy a grinder bench...would you use a "6" or "8" wheel?

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Originally Posted by mainaman

One solution is to not use gloves, I don't and have never had problems.

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Yes stefn, I think I will put aside the gloves...hoping I will be safe :-)

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Originally Posted by HoningStones

Yes I plan to buy a grinder bench...would you use a "6" or "8" wheel?

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get an 8". you'll thank yourself later

I've never had a problem with a Dremel but I put my figure on the opposite side of the blade when polishing. When I feel heat I dunk the blade in cold water to cool the blade.

The blade in question is toast.

So on a dremel you run bigger wheels because the dremel has a low level of power and they run slower. On the bench buffer you run smaller wheels because it gives you a lower feet per second. Four inch wheels are easy to find although if you can get your hands on three inch wheels that's even better. There is a lot of information in the stickie in the workshop forum. There is also a lot to be said for hand sanding and hand polishing.
http://straightrazorpalace.com/works...wers-here.html

What the colours mean when tempering high carbon steel:


Faint-yellow – 176 °C (349 °F) – engravers, razors, scrapers
Light-straw – 205 °C (401 °F) – rock drills, reamers, metal-cutting saws
Dark-straw – 226 °C (439 °F) – scribers, planer blades
Brown – 260 °C (500 °F) – taps, dies, drill bits, hammers, cold chisels
Purple – 282 °C (540 °F) – surgical tools, punches, stone carving tools
Dark blue – 310 °C (590 °F) – screwdrivers, wrenches
Light blue – 337 °C (639 °F) – springs, wood-cutting saws
Grey-blue – 371 °C (700 °F) and higher – structural steel

The razor in the first picture has gone well past faint yellow on the bevel. Removing the entire bevel and grinding a new one might save the blade, but it's a big job and not for the faint of heart. You are NOT going to do this kind of work without some serious time on a low grit stone, if doing it by hand. Doing it by machine would be faster, but it is ever so easy to overheat the blade, as has been discovered and thus not recommended.

I know I'm inviting disagreement but whenever I've said this to other straight razor enthusiasts I've only had nods and "Oh Yearhs.

Dremel = natural enemy of the straight razor

There can be many qualifiers to this; some people can manage a Dremel and find it a useful tool - these are experienced people who have had their share of disasters and have learned from them. When a new guy picks up a Dremel and applies it to a straight there can only be one outcome.

Sorry to say but any colour change it's goosed, the colour that you might get away with would be yellow/light straw colour.
There will also be damage from beyond where the colours stop as heat spreads so think of it as the ripple effect when you throw a stone in water.
Time will tell when you try to hone it up, if the edge crumbles away then it's lost it's temper.


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if i have to use a dremel, i always have a glass of cold water near by to dip it in if I detect any heat.

The blade might be toast, but I would have to give it a try just to make sure