Using Sanding Disks for razor restoration

[vladsch]

Now that the batch of razor boxes are done (you can see the results in the Buy/Sell/Trade forum under Boxes threads) I wanted to share with those of you who got the sanding disks some points that you should keep in mind while working on your razors with sanding disks.

1. Be patient. RichZ PM'd me that the 100 grit disks were not enought and he resorted to using a dremel grind wheel, which worked fine, but when he got close to the edge it overheated ruining the blade. 100 grit disks are enough if you are more patient. You can regrind the razor with them but sanding high carbon steel takes time unless you have a Burr King like Bill's. Dremel grind wheels are too dangerous to use on razors. I ruined a blade when I tried it using it out of impatience.

2. When working near the edge you have to go slow or you will overheat the steel and ruin the hardening. I find that a dremel is too fast even at its slowest speed. I prefer a flexshaft with a footpedal and use lowest setting.

3. To work near the edge you can put a small puddle of water on your work surface about the size of a quarter (smaller than the disk diameter). Periodically dip the center of the sanding disk into it to get the water on the disk. At slow speeds the water will travel to the edge of the disk, at high speeds it will be splashed off completely. You will see the disk pushing the water on the steel as you sand. This keeps the leather mandrel dry and the sandpaper and steel wet preventing overheating.

I used this last technique to sand out deep grind marks right near the edge on Garry's DD Goldendge. Took a bit of time but with the slow speed and always keeping the sandpaper wet there was not chance of ruining the edge by overheating it.

4. When the disk gets used up it will tend to heat the steel more due because it is now flat and is rubbing the steel more than sanding it. Replace the disk when you see the used part starts to look much smoother than the unused part of the disk.

If any of you have completed a restoration project please post some pictures, I am curious to see the results.

I now have more time to start restroing all those razors I picked up a month and a half ago. So will be posting some pictures soon.

[urleebird]

Excellent advice... I better hurry up and finish the updated version to my restoraton CD befor McGyver beats me to it.

[FiReSTaRT]

Since I see two experts hanging out in this thread, I might as well ask... Would it be possible to use a 1/4 sheet sander to polish out barely visible (you have to try really hard) nicks from a blade? If the answer is yes, what's the grit that I'd have to use? Any advice on the technique?

[jmsbcknr]

Since I am new at trying to restore a razor I must ask if there are any tips for working around the edge with a dremel. Right now the rest of the blade is fairly straight forward. But when I get close to the edge I am scared of chipping the bevel. Right now when I look at the razor I am working on, the top part looks pretty good--not as good as Bill's work--but pretty good never the less. But there is a line near the edge that stands out as not touched. I tried with sanding stick to get a bit closer but that still does not get me close enough. Any of you tape the edge with electrical tape to protect it during the sanding process?

jmsbcknr

[vladsch]

Since I see two experts hanging out in this thread, I might as well ask... Would it be possible to use a 1/4 sheet sander to polish out barely visible (you have to try really hard) nicks from a blade? If the answer is yes, what's the grit that I'd have to use? Any advice on the technique?

If you mean nicks in the edge then those you just hone out. If they are barely visible then a 4k Norton would do it.

If on the other hand you mean pitting on the blade then those you need to sand out. If you don't have sanding disks then you can do it with sandpaper by hand. I posted a thread a while back on my hand sanding project here.

Since I am new at trying to restore a razor I must ask if there are any tips for working around the edge with a dremel. Right now the rest of the blade is fairly straight forward. But when I get close to the edge I am scared of chipping the bevel. Right now when I look at the razor I am working on, the top part looks pretty good--not as good as Bill's work--but pretty good never the less. But there is a line near the edge that stands out as not touched. I tried with sanding stick to get a bit closer but that still does not get me close enough. Any of you tape the edge with electrical tape to protect it during the sanding process?

If you make sure that the rotation of the mandrel is off the edge and never into the edge you won't chip the bevel but working around the bevel will require you to hone a new bevel not matter what you do. You will probably get the rotation wrong at least once. Once is usually enough to keep you very alert for the future. It is a hair raising experience, not to mention blade chipping one and I don't mean just edge chipping one. You will most likely get a nice chunk of blade chipped out.

That said, I find that the dremel speed is too high for me to work near the edge. You should look into getting a foot pedal control for a flexshaft and plug the dremel into that. It will give you much finer control and you get to vary the speed with your foot depending on which part of the blade you are working.

You can always sand out the area near the edge by hand. You have to do one grit at a time with both the disks and hand sanding. Same grit for both, otherwise you will have a hell of a time trying to get the boundary between disk/hand sanded areas to match.

As for electrical tape, I only use that to protect the edge and my fingers if I am not working near it. Otherwise you will see a sharp line between unprotected sanded area and the protected unsanded area.

[urleebird]

Again, very sound advice by Vlad. I would only add two things.

• A cordless 7.2 volt dremel has two speeds. The slower one works fine. I would not get close to the edge with any grits larger than 320. Use fresh discs. Once they become worn, they heat everything up too much.
• Make a wooden jig with recessed magnets to hold the blade in place in which the cutting edge winds up flush with the wood surface. Then the rotation of the disc will not be as critical. You can work right up to the edge without mishaps this way. ( A real tip here: If you can find some copper plate, with thick being better, go ahead and use that instead of wood. It will help dissipate the heat generated at the cutting edge.) Use light pressure and keep the disc moving.

Use an old blade that is useless to practice some of your "moves". Intentionally heat the blade edge with the discs until it turns color; usually brown first. Then, you will have an idea what not to do on your good blades. Once the blade turns ANY kind of color other than shiny, the blade is dead there in that spot.

[mgraepel]

I'll hop in here to say that if any of you need industrial-strength magnets I can ship them to you. I've salvaged quite a few from old hard drives and these suckers are exceedingly strong. I'd just want you to pay the shipping cost is all (and you can even pick the method!)

[vladsch]

Again, very sound advice by Vlad. I would only add two things.
[list]
A real tip here: If you can find some copper plate, with thick being better, go ahead and use that instead of wood. It will help dissipate the heat generated at the cutting edge[/color].) Use light pressure and keep the disc moving.

Great idea on the copper plate. Now if you coat the edge of the blade with a bit of thermal compound (white paste) before putting it down on the copper it will disipate heat even better and without presure. The compound is used in electronics between power transistors and heatsinks can be bought on line or in any electronics supplier and is cheap (less than $10 for a large tube for a life-time supply). It is non-corrosive and non-drying and wipes off clean. You guys in the US are lucky, you have Fry's to get cheap electronic supplies. Last time I was in Dallas/Fortworth area I practically camped out in that wharehouse store. Ammazing prices and selection. Stuff that in Montreal is hard to find, even on special order, is there right on the shelves and in huge quantities.

For magnets you can also pickup a few "rare earth" magnets like I use for latches on boxes and they will hold anything down (I use 1/8" rod magnets). Don't use too big a diameter (a few at 1/4" should do it, 2.5 lbs of force per magnet) or you'll have trouble removing the razor from your jig without damaging it. The magnets are sold at Lee Valley if you can't find them locally.

[FiReSTaRT]

The issue are a couple of very small dents on the cutting edge itself. If I had to use the hone, how would I get'em out? Just doing the X-pattern until they disappear?

[vladsch]

I'll hop in here to say that if any of you need industrial-strength magnets I can ship them to you. I've salvaged quite a few from old hard drives and these suckers are exceedingly strong. I'd just want you to pay the shipping cost is all (and you can even pick the method!)

Careful about shipping strong magnets by air. As far as I know there is a restriction on them for ground shipping only.