Cutting Knife Blanks???

S

slaveman

Joined
Feb 1, 2011
Messages
7
Hello Everyone. This is my first post...

What is the most efficient way to cut blanks???

I have 1/8" x 2" x 72" stock (CPM154). The mill-scaling has been removed, but I still struggle cutting out the blanks. I've had the same problem with CRA 1095.

I've tried hand-held cutting wheels (inaccurate and burns the steel if I'm not careful), and reciprocating saws (difficult). I've even tried drilling out the blanks with a drill-press (takes forever). Now I've just resorted to using a hacksaw (which also takes forever).

What is the easiest way of doing this? Would a metal-cutting chop saw work? I'm willing to buy the necessary tools. I just want to make sure I buy the right tool for the job.

Any input would be greatly appreciated! Thanks!
 
I think it's important to note that I don't have any problems grinding. Once the blank is cut, I'm fine.

I'm just looking for a more accurate, efficient way...

Thanks
 
The most efficient way to cut knife blanks. In order of efficiency (as I see it):

email file to waterjet guy
CNC mill
vertical metal cutting band saw (this is probably the best choice)
angle grinder with slitting wheel
belt grinder
hacksaw
belt sander
bench grinder
hammer and cold chisel
dremel
dull rock
selective rust erosion
use your teeth
 
I gotta say, that on a cost per cut basis, Nathan has it right. For most of us, the bandsaw wouldbe the cheapest and easiest to do ourselves. Now, if you have a buddy that works in a machine shop or waterjet operation, that might be different.
 
Get a metal cutting bandsaw, and use bi-metal blades 18-22 teeth per inch will do for 1/8th stock.
 
I use a Harbor Freight Horiz-vert metal cutting band saw. Its not the greatest....but does the job. Nothing worse than a weekend cutting blanks though....:eek:
 
Thank you guys for the quick replies!

It sounds like the metal cutting bandsaw is the way to go. The Grizzly, Harbor Freight, and Shop Fox models seem to be pretty affordable.

I've actually considered the waterjet route though. I'd really love to have the consistency and professional results they provide. My only concern has been the shipping costs.

Have Admiral ship the steel to the waterjet. Then ship the blanks back to me. Then after grinding, ship them to Peters for heat treating. And finally ship them back to me again to finish them.

It sounds a little over-the-top (and expensive) for me. But I'm sure the results are excellent.

Do any of you have any experience with waterjet services? It seems to be rather expensive when everything else is taken into account...
 
I use a portaband metal cutting band saw for alot of things. However, I find it just as easy if not easier to grind them to profile with a kmg 2hp grinder and 36 grit blaze belts on the contact wheel, not the flat platten. The belts last a long time for rough profiling something as thin as 1/8 inch stock.
 
anything you can do to keep the dust to a minimum is a plus..... another vote for bandsaw.
 
Bandsaw or waterjet.

I once used a jigsaw to cut out a blade. It worked OK, but isn't ideal.
 
These guys are right on the money. One suggestion I would make is to fill out your profile with your location. This way someone here might be able to point you in the right direction for water cutting services.
 
Yep, I used a Mikita 4 inch angle grinder when I first started with the thin cutting wheels. It worked okay, but I was never fully comfortable because I was always waiting for that thin disc to explode and send chunks flying at me. I've heard too many stories about shrapnel wounds from those things! When I had the chance I picked up an old Dayton Vert/horiz. bandsaw, got some really good bi metal blades and now I use it to cut out all my blanks and handle material as well.:thumbup: Band saw is a great investment and will really help in many areas.
 
Had a friend at Delta Air Lines end up with a big piece off a cut of wheel in one of his balls. he nearly became one ball Sean. Took the doctors like six hours of vascular surgery to put him back together. I tell everyone I know do not use a cut off wheel. You've been warned it only take one second to make a life long mistake. Donald
 
I've had several of them break and never have I seen them come off with enough force to castrate a clothed person. Are we talking about 4" angle grinder cut-off wheels on standard, 4" handheld tools? Or, perhaps, was Sean running the cutoff wheels naked?
 
I know of a guy in a bodyshop that had one come apart and hit his facemask, cutting through it and taking some skin off of his eyebrow. He was close to losing that eye. Granted, he was probably using a larger/faster grinder and wheel than the 4" that most of us use.
 
slaveman said:
Do any of you have any experience with waterjet services? It seems to be rather expensive when everything else is taken into account...
Click to expand...

Yes, almost exactly as you described it. "expensive" is a relative term... if you want one or two blades, it's not worth it. Better off ordering the barstock and doing all the cutting in-house, even with a hacksaw. And honestly if you're doing a couple blades you're talking 5 minutes tops with the hacksaw. Hack to rough shape and grind the main profile with an old coarse belt. It's the quickest part of making a blade.

If you want a half dozen or more, it becomes cost-effective. Same goes for the bandsaw actually, how often are you really going to use it? Apparently I'm the only one on the forums who thinks this way, but you should compare the cost of tools/services to how long they will take to pay for themselves in time/labor saved. Unless of course money is no object... :rolleyes:

Time is also a factor; sometimes your WJ and/or HT guy just get busy and you're twiddling your thumbs for a month. Even when all goes perfectly you're looking at several days shipping time in there somewhere.
 
AcridSaint said:
I've had several of them break and never have I seen them come off with enough force to castrate a clothed person. Are we talking about 4" angle grinder cut-off wheels on standard, 4" handheld tools? Or, perhaps, was Sean running the cutoff wheels naked?
Click to expand...

4" 90 degree angle grinder with a Norton wheel. Workpiece was a thick piece of Aluminum and it was felt the piece got hot and either clossed on the cutting blade or it tried to "weld" to the blade. The work piece was waist high and secured with clamps to a steel work table that would take at least eight grown men to move so I don't think vibration was a problem. Anyway the blade let go and his junk was on the same level and it got him. All tools are maintain by a department that does nothing but neumatic tools and no fault was reported with the grinder as far as I remember. It not to uncommon for the tin benders to make modifications to there tools but I do not think this one was juiced up any. Donald
 
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