Odd blade behavior

kelbro · 07-11-2008, 12:25 PM

I have an old Sheffield quarter-hollow blade that has been giving me fits. Setting the bevel was not a problem. Honing on the lower grits yields a shaving edge, just a little 'gritty'. It feels great on the TPT. The problem seems to occur when I get to the higher grits or try to strop it with either a pasted paddle or the linen/leather, the edge simply goes away. It will not pass HHT and will only make about 1/2 of a shave before it becomes useless.I have seen this situation before in sharpening knives and was usually able to attribute it to cheap steel but this is not a cheap blade. Is it possible that this blade is just not tempered very well? I have put great edges on a lot of razors but this one has me pulling my hair out, literally

Thanks for any suggestions.

nun2sharp · 07-11-2008, 10:42 PM

I cant help you, but maybe some one else can. Bump

The Topher · 07-11-2008, 11:11 PM

How was it restored? Did you use a dremmel on it? Did you see any grind marks on the blade? I have had blades do this and I have found 2 things from it. 1 the metal has been heated through polishing or grinding and now won't hold and edge. Sometimes you can remove some more metal and it works again and sometimes it is just dead. 2 you are doing something wrong in honing like building a wire edge that when going to high grits or shaving with it causes the razor to go dull when used. So tell us a bit about how you fixed it up and how you hone it plz.

kelbro · 07-12-2008, 12:17 AM

Thanks Topher. I was sort of thinking along those lines. I bought this razor in this condition so I have no idea how it was refinished. I have viewed the edge under high magnification and do not see any sign of a wire edge or a rolled edge, both of which I have seen before and are easily recognized. I plan to try again to get an edge that stays.

kelbro · 07-12-2008, 04:04 AM

Well, same thing tonight so I thought that I would try something that I read on this site. Taping the spine. I have used this idea of a secondary bevel on working knives and it seems to work there. It makes touchups a breeze for several honings until you have to reset the primary bevel. The edge on this razor got up and stayed up through my fine hones and 50 laps on the strop. I'll try shaving with it in the morning and see how it holds up. Thanks for the suggestions.

The Topher · 07-12-2008, 05:00 AM

I have also had a few where doing 5 -7 laps backhoning on the finish hone has helped

Philadelph · 07-18-2008, 11:42 PM

Is it a wide bevel? If so, those thick grind old razors can take hours to really get the edge nice as I've found.

kelbro · 07-19-2008, 12:08 AM

Thanks Alex. Not a wide bevel but it's pretty thick. Ithas provided three good shaves since the spine-taping.

JMS · 07-20-2008, 09:03 PM

Based on all of your info it sounds like you had a double bevel on one side Which caused me all sorts of fits with what is now my favorite shaver!

Howard · 07-23-2008, 01:38 AM

Yes, it's a distinct possibility. The interplay of steel type and heat treatment is one that requires a lot of care and insight. Even commercial heat treaters don't get the same results every time. The edge behavior you're describing sounds a lot like either bad steel, bad heat treating, or both.

kelbro · 07-23-2008, 02:56 AM

This may be worth a follow-up. Tried the un-taped honing again. Passed the sharpie test and I could see the bevels meeting under the scope. Got a sweet edge on it and made it cleanly through about 1/2-3/4 of a shave and away she went. Taped it again, put the new edge on and it went two more shaves and felt good enough for a third. I give up! I put a coat of baby oil gel on it, wrapped it up and stored it in the medicine cabinet. Too many good razors in the rotation to keep fighting with this one.