Badly cracked blade, can it be shortened?

[cb91710]

Ok. Is this without using an ice block? I'd have thought that would have made heat issues obvious with quick melting before it got too hot. Isn't tempering temperature above boiling point of water?

That's the point... you want to keep it well below that point. While 200 degrees won't hurt the temper, without careful monitoring or solid cooling, it will get to the point of color change before you can say "what just happened?"

[ladykate]

Ok. Is this without using an ice block? I'd have thought that would have made heat issues obvious with quick melting before it got too hot. Isn't tempering temperature above boiling point of water?

Yes. I don't use an ice block - I use a wetted towel. It helps hold the blade, too. Go easy and shuffle it around a bit. It won't lose its temper. Done it a lot. I don't seem to sense any danger when cutting the blade but I have nicked myself several times when handling it afterwards - polishing and such. It helps a lot to NOT have a sharp blade - if it is sharp now, then butter knife it. Gloves get in the way for me but YMMV.

[Toddy]

Bench grinder but make sure the wheel is newly dressed. Only take a little off at a time and dunk in water.

The best thing to use would be a bench whetstone as these don't draw temper, but not many people have them.

[DominoM]

I'd don't have access to a bench grinder, so I can't go that route without buying one. I was looking at some yesterday and there was a Draper 06498 one I would have jumped all over if it had been variable speed, but alas it was fixed speed. It had 3" wheels which I think is one of the grind sizes for razors and has a flexible dremel type shaft coming off it. Was a tidy little unit for someone with limited space for a workshop like me and if it was that bit more controllable as a dremel replacement I'd have got one.

I've drawn up the plan for the blade shape and scales, my face shield arrived this morning but I'm busy today, so will probably attempt this tomorrow.

[cb91710]

Being inexperienced, a bench grinder is the last thing that you should be using on a straight.

This isn't a camping hatchet or machete.

[brother cavefish]

i did it on my disc grinder and just kept dipping it in water every couple of seconds of grinding-worked fine

[cb91710]

That's why I qualified the comment with "being inexperienced"

Someone who has never used a power tool to grind a piece of thin metal has no idea how quickly they can build heat to color-changing levels.
My first experience was using a cutoff wheel on a piece of 1/8" music wire for a model airplane's landing gear. I was holding it about 6" away from the cut and it raised a blister on my thumb.

[Slash McCoy]

Start cutting from the spine, with a thin cutoff wheel. Little bit, little bit. Softly softly, catchee monkey. Then, when the end piece drops off, start shaping your tip. Ice is nice. Keep your work cool. Yes, it would be very nice to end up with a usable shorty. But remember, it is useless as it is, so if you mess up you haven't lost anything. This is one of those "go for it" situations.

[DominoM]

Can it be shortened? Yes it can!

I ended up changing my mind during shaping the new end on it's shape. I hit this shape while working towards the plan and really liked how it looked, so added the corners and stuck with it.

I did the cut on a big block of ice, and temperature was never an issue. I was having problems with the cutting blade sticking and needed to keep the cut wet for lubrication, so it actually turned out very useful having a supply of water next to the cut. Dremel for a couple of seconds, slide cut onto and back off ice, repeat until it dropped. Ice melted like mad, but the blade only ever felt cold to my touch - I didn't bother with gloves in the end.

I shaped the spine corner with a 60 grit sanding drum, and hand sanded with 120 grit to smooth out a bit. I did the blade corner by hand on the 120 grit.

I'm part way through polishing it up and it's actually needing more attention to the temperature than the cutting did. I'm just using a felt disc on the dremel loaded every minute or so with chromium oxide cutting compound as the blade wasn't in too bad condition.

[brother cavefish]

Can it be shortened? Yes it can!

I ended up changing my mind during shaping the new end on it's shape. I hit this shape while working towards the plan and really liked how it looked, so added the corners and stuck with it.

I did the cut on a big block of ice, and temperature was never an issue. I was having problems with the cutting blade sticking and needed to keep the cut wet for lubrication, so it actually turned out very useful having a supply of water next to the cut. Dremel for a couple of seconds, slide cut onto and back off ice, repeat until it dropped. Ice melted like mad, but the blade only ever felt cold to my touch - I didn't bother with gloves in the end.

I shaped the spine corner with a 60 grit sanding drum, and hand sanded with 120 grit to smooth out a bit. I did the blade corner by hand on the 120 grit.

I'm part way through polishing it up and it's actually needing more attention to the temperature than the cutting did. I'm just using a felt disc on the dremel loaded every minute or so with chromium oxide cutting compound as the blade wasn't in too bad condition.

welcome to the world of restoration right on my man, right on

[Slash McCoy]

Nice work. It will still be a pretty good razor, and one you can take particular personal pride in.

[DominoM]

I've tweaked my scales design to fit the new blade (done in Inkscape) and took into account BillEllis's post about wedge allowances. I've used double sided tape to stick the two lemonwood blanks together and printed, cut out and stuck my design to them. With the way my projects are multiplying I might have to make a holster for my dremel to keep it handy



After taking the picture I moved the template to the edge of the wood as I had half an idea to use the spare on the end for the wedge. I'd only used spray glue on the paper so I could peel it off easily until I was satisfied with positioning. Now both wood and paper are glued and it's sat under a speaker to hold it flat.

[Slash McCoy]

I get a large ice cube and sit it on the table. Resting the edge on it, start grinding away the unwanted steel with a sanding drum, always keeping the edge in line with the rotation of the tool (if you try to grind across the blade it will snap). As the blade gets warm it "cuts" deeper into the ice, providing more cooling contact.

If the edge ever gets too got to touch you are in trouble.

Hey, those are some cute lil shorties you got there!

[DominoM]

Bit of a wait since my last progress for tools to arrive. I'd decided to get a pin vice for drilling as I really didn't feel comfortable putting someone out everytime I wanted to drill two 1.6mm holes. I also decided to get a better fremel (fake dremel) as my old one tended to choke on heavy work and I needed the flex adaptor anyway. I also wanted the option of getting a drill press adaptor if the pin vice didn't work out. I compared the Challenge Xtreme Mini Tool kit with a Dremel and it'd end up over $75 cheaper with the Xtreme. So that's what I went for and I couldn't be happier with it.

I used the fremel and a sanding drum to shape to about 1mm around my design on the blanks. From there I hand sanded with 60, 120, 150 grit progression to put the final shape on the scales. I laid a sheet of 60 grit on a granite chopping board and sanded the wedge shape there. I then separated the scales and cleaned the tape off with white spirits. I learned a valuable lesson here - sand the insides flat before sticking them together. My hand slipped and I put a nice makers mark (aka fingernail gouge) on one of the scales trying to push it across the 60 grit on the board. I went back to 60, 120, 150 grit progression to reduce this, but it was pretty deep and I didn't want to mess the shape up too much so left a light scratch as a reminder.

I used 10ba bolts to mock up the assembly and kicked myself for not running a pipe cleaner through the pivot hole on the blade first. Some of the gunk from cleaning it was still in there, hence the dark marks on the inside of the scales. I removed the blade and went back to the fremel to shape the wedge to the scales, stopping about 1mm short. After that I super glued the wedge into place and finished the shaping with a 60, 120, 150 progression.

I then made a little drying hook out of a paperclip and gave the scales a coat of tung oil. Here they are after drying overnight.



They are still a little damp, so I switched the hook from the wedge end to the pivot end and will leave until this evening when I can smooth down with 0000 steel wool and apply the next coat.