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View Full Version : How do I cleanly cut a razorblade?



Benjamin Borowsky
09-19-2003, 08:29 PM
I am making a device that butts two razor blades together, forming a "T". A standard razor blade is too tall and too long, so I want to cut it down. I tried a dremel, and it worked, but it was rough and dicolored the metal, which I don't want. Is this a job for a metal shear? Would it deform the blade (which has to remain completely straight)? Any suggestions? Thanks in advance.

B2

gbritnell
09-19-2003, 10:36 PM
Being as razorblades are extremely hard as to hold an edge, if you tried to shear one I'm sure that it would just shatter. Your best bet would be to use the Dremel or some type of grinder with a cutoff wheel to cut the blades down close to the size you want. Then make a clamping fixture to hold the piece with a small amount protruding from the edge so that you could hold it up to a sanding disk and grind away the remaining portion. If you were careful with the fixture you would only kiss it when you got down to the finish size. I hope this helps

Offyman
09-19-2003, 10:39 PM
If you have access to a surface grinder and a toolmakers vise the job should be fairly simple and the opposing sides would be parallel.
Lee

bdarin
09-19-2003, 10:41 PM
Try scissors.

randyc
09-19-2003, 10:43 PM
If you have a carbide (or diamond) scribe, you might try scoring the blade and then snapping it (in a vise, with safety glasses:)

Andrew
09-19-2003, 10:44 PM
just thinking out loud here but you could try scoring a line with a carbide scriber and then snapping it in half. You could always grind the edge after if it's too rough. hope this helps
Andrew

wierdscience
09-20-2003, 01:31 AM
Actually razor blades are not extremely hard,you can shear them with a pair of sharp aviation snips assuming we are talking single edge razors,anything thicker like an exacto blade would be done with abrasives,as for defroming the edge,just use the snips in the normal manner with the waste side of the cut on the off hand side of the blade.

WJHartson
09-20-2003, 01:36 AM
I don't know the quantity you want but you may be able to purchase what you want for a reasonable price. Check with one of the blade manufacturers and see what they want for a blade made to your specs. I the past I have gone to manufacturers to see what they would charge for one of their product slightly modified. In several cases they were cheaper than the standard item. Packaging cost run the price up. If you can get what you want in bulk it will be a lot cheaper.

I think that you could shear them and not have them deform. I may try one tomorrow and see shat happens. I have sheared thin spring stock without any problem.

Joe

Thrud
09-20-2003, 02:59 AM
Benjamin

Try a gullotine type paper shear that is not dull (crisp cutting edges). You could have it cut with a Laser or water jet.

In my youth I built a CO2 laser at home that would blast through razor blades. Made it from a (bad) plan in SA ("Amatuer Scientist" column).

[This message has been edited by Thrud (edited 09-20-2003).]

darryl
09-20-2003, 04:33 AM
Put a fresh sharpen on a pair of scissors, have at it.

Evan
09-20-2003, 01:31 PM
Thrud,

You actually built that laser? Cool. I considered it too. I also always wanted to build the linear accelerator he had in that column. I still have the plans. Never did build it as I figured I wanted to have children.

Benjamin Borowsky
09-20-2003, 09:38 PM
Thanks, guys. I'll try the shears and let you know how it works out.

B2

Mike Burdick
09-20-2003, 10:51 PM
Benjamin,

I cut them before. As others have said, I scored them with a carbide scribe; then supported the side of the razor I wanted to keep as close to the scratched line as I could. I "flexed" the blade with a plier until it cracked. Once cracked, I smoothed the blade with light touches to the grinding wheel until I achieved the precise length wanted.

Keep in mind, since they are so hard you might shatter some before you get what you want. One other thing - these blades grind very easy so you don't have to have the scratch line exactly where you want the finished length. When I ground mine, I used a thicker piece of aluminum as a backer plate to act as a heat sink.

Thrud
09-21-2003, 11:00 PM
Evan:
Yup, but lots of modifications so I could experiment with different gases (pretty colours!) - 'course not everything would lase, but WTH. In retrospect it was probably not a high enough vacuum. Made a 500W (gestimate) ruby laser too. That one popped holes in 10Ga. They disappeared during a move from one town to another. My parents got paid for them by the moving company and I got squat (story of my life - at least I have never had a divorce or shotgun wedding - Thank you God) http://bbs.homeshopmachinist.net//biggrin.gif

Shed Machinist
09-21-2003, 11:07 PM
Thrud, would you happen to have the plans to this laser?

Benjamin Borowsky
09-22-2003, 08:00 AM
Yes, if you do, Thrud, can I get a copy of those as well? I will need a quick way to cut down single edged razor blades to fit a machine I'm working on. The cheapest I can find someone else to do it for me is about 25-30 cents a piece, and I need it to get down to about 10. Therefore, the DIY method sounds about right.

B2

Evan
09-22-2003, 01:21 PM
Plans avilable here:

http://www.tinkersguild.com/cgi-bin/SoftCart.100.exe/index.html?E+scstore

This includes every Amateur Scientist column ever published on CD

Also check this:

http://www.technology.niagarac.on.ca/people/mcsele/lasers/LaserLinks.htm

[This message has been edited by Evan (edited 09-22-2003).]

Benjamin Borowsky
09-22-2003, 05:50 PM
Well, scissors (and shears, etc.) didn't work so well. On the bright side, though, I did make some very purty metal chips and fragments http://bbs.homeshopmachinist.net//smile.gif

The scoring and snapping works very well, although very slowly. I'll die of old age before I finish the job.

And a laser needs to be, so I'm told by several different makers, a 500 watt job to cut through the metal... does that make any sense? Thrud, did you make a 500 watt laser?

B2

[This message has been edited by Benjamin Borowsky (edited 09-22-2003).]

WJHartson
09-22-2003, 06:39 PM
B2,

Have you tried to get a quote from one of the razor blade manufacturers making a blade to your specs. I have on several occasions had pieces made that were actually cheaper than the unmodified piece. Let the manufacturer qoute the cheapest way to package the product, that also makes a difference in price.

What type of razor blade are you trying to cut?

Joe

Joe

randyc
09-22-2003, 06:40 PM
B2:

Sounds like you have a LOT of these blades to modify. Maybe there are other alternatives if the quantity is high enough.

For example, search the web for manufacturers and see if it's possible to buy the blades in coil stock. If so, then other methods might be suggested.

A clever guy should be able to come up with a roll-fed, machine (maybe even hand-operated) that feeds, scribes and breaks. Or feeds and is cut off with something like a dremel tool with a diamond blade (a miniature chop saw).

Not having to handle single blades would be a big plus, both in terms of time and safety.

Cheers !

tonydacrow
09-22-2003, 07:13 PM
How 'bout this... If you have quite a few to do, clamp them together and use an angle grinder or (if you're concerned about temper) grind them on a tool grinder w/ a water cup. Alternatively, put them on a milling machine once they're clamped together and use a carbide mill with or without coolant. The stack will support itself and prevent the thin blades from shattering when you hit them with the grinder/mill, etc.

[This message has been edited by tonydacrow (edited 09-22-2003).]

Thrud
09-23-2003, 04:59 AM
Benjamin
It only takes a few watts focused properly (TEMoo gating increases power - "high speed strobing") to burn a razor blade. Higher power does it much faster, industrial laser use nitrogen or oxygen coaxial jets to blow metal out of the kerf. A homemade laser slags big ugly holes.

The ruby laser was about 500W (estimated). The ruby rod has to be ground precisely on each end to 1/20 wave and parallel to one another or it will not put out much power. One end is a gold mirror, the other end is a partial mirror. I used several high power strobes with rod mounted down the center of the strobes and enclosed them in a reflective housing to maximize excitation of the rod. Don't have plans for either both lost in the move with my other experiments.

There are lots of great optics that can be purchased for CO2 lasers now like germanium windows (Edmund Optics) and hot/cold mirrors and specially coated optics for focusing. If you are going to attempt experiments with CO2 lasers make sure you get adequate eye protection (not cheap - Edmund has them) as the beam is invisible and quite dangerous. Argon gas laser or YAG Slid State laser (commonly used for engraving and laser welding) can operate in the visible spectrum, Argon is nasty because the human eyes are hyper sensitive to the green spectrum and easy to damage.

One thing I found with mine was the HV DC power supply they recommended did not work well on mine. I ended up with a 40Kv .2A (very dangerous) power supply and a water cooled gas jacket. Mine would hold a hard vacuum for days. I used HeNe (red light) to get everything lined up and to do holograms.

Safety Note:
ANY LASER CAN BLIND YOU!!!

Thrud
09-23-2003, 05:05 AM
Evan

Love that N2 laser! Thanks for that link - oh, oh - the gears are a turnin'! http://bbs.homeshopmachinist.net//biggrin.gif

[This message has been edited by Thrud (edited 09-23-2003).]

Benjamin Borowsky
09-23-2003, 07:45 AM
I think the answer is either A) pay someone else to do it (the price is about .20-.25 per blade) or B) get coil stock and jimmy up some semi-automatic doodad to cut them to length. Thanks, all, I really appreciate it.

B2

Evan
09-23-2003, 05:36 PM
I saw a show recently on building cruise ships. They cut the steel plate with giant CNC lasers with the plate just under water. It minimizes distortion and makes a cleaner cut, no finishing required. Real death rays.

Thrud
09-24-2003, 05:16 AM
God, I love tools!

reality checker
09-25-2003, 12:00 AM
Wire EDM. I have cut thousands with a wire.
Stack as many as the machine can cut well, clamp or mount in a low melt point alloy. I think that we were doing them for a medical application for 3 cents each.

randyc
09-25-2003, 12:03 AM
Wire EDM --- Jeez, what a GREAT idea !