Thread: When alum meets carbon steel

I had my first real cut, yesterday, since I began using a straight razor. It was on the second pass over my neck, about half an inch wide and bled instantly. I grabbed the alum block and rubbed it liberally on the cut and surrounding area. I then proceeded, finishing up my neck and doing touch-ups on my face. During cleanup I noticed that there were two tarnished spots on the blade. Both spots were right above the edge where the lather and whiskers collect. It seems that I went too close to the area of the cut and transferred alum onto the blade. After cleanup I dried the blade, stropped, and then took some Maas to the blade. Most of the tarnish was removed. I am going to try to get the rest of the tarnish tonight.

Recently, there was a thread on the forum that warned about not getting alum on the razor's tang from having alum on the fingers. When I read that I thought it was good advice and filed it away for future reference. Now I know to be careful if I use alum on a cut during the shave also. I hope sharing this experience might help others.

Originally Posted by Leatherstockiings

I had my first real cut, yesterday, since I began using a straight razor. It was on the second pass over my neck, about half an inch wide and bled instantly. I grabbed the alum block and rubbed it liberally on the cut and surrounding area. I then proceeded, finishing up my neck and doing touch-ups on my face. During cleanup I noticed that there were two tarnished spots on the blade. Both spots were right above the edge where the lather and whiskers collect. It seems that I went too close to the area of the cut and transferred alum onto the blade. After cleanup I dried the blade, stropped, and then took some Maas to the blade. Most of the tarnish was removed. I am going to try to get the rest of the tarnish tonight.

Recently, there was a thread on the forum that warned about not getting alum on the razor's tang from having alum on the fingers. When I read that I thought it was good advice and filed it away for future reference. Now I know to be careful if I use alum on a cut during the shave also. I hope sharing this experience might help others.

Is the tarnish actually harmful, or is it just cosmetic ? I only ask because I use alum for grip, so there is a good chance I could get it on the steel. Cosmetic issues don't worry me, but obviously if my razor is going to rot then I will be more cautious.
After shaving I dry and give my razor a squirt of water displacer.
Thanks ed.

Blood will also tarnish steel in a heartbeat.

Edhewitt, I don't know if it the tarnish is harmful to the blade. Hopefully someone on the forum could answer that. I am not super picky about having a mirror finish but I do like to keep things clean.

Pixelfixed, Good to know. Hopefully that is a lesson I won't have to learn firsthand!

Originally Posted by pixelfixed

Blood will also tarnish steel in a heartbeat.

Os told me that one too, he said it promotes rust. Though if that's the case I should not have a blade left .

Thanks for the warning regarding alum!

I've heard toothpaste is good for cleaning surface marks, since it is on right at hand for me when I shave, its always my first port of call.

For cuts you should use a styptic pencil, which works on a localized area, rather than rubbing an alum block over a large surface. That is likely the reason why you got alum residue on your razor. Back in my "styptic days" once the bleeding had stopped (which doesn't take long) I'd just relather and shave around the cut, and never had any issues with blade tarnish.

I've used alum on my fingertips for years to ensure the my grip without any ill consequences. I'm not saying alum wasn't the culprit, but could it have been the blood?

Iron in the blood is a different ion than iron in steel. Doesn't react the same way as far as rusting goes. It just leaves dark stains. But it is a liquid, and if it gets into the steels pores and isn't cleaned out well will cause rust as much as water.

What I mean is the iron in the blood doesn't react and rust, the blade will rust because blood is a liquid holding moisture on the steel.