How close to pattern with angle grinder?

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drysideshooter

Joined
Dec 6, 2011
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244
How close do most of you try to get when cutting out a knife pattern using an angle grinder with a cutting wheel? I just tried using my angle iron with a cutting wheel on an old saw blade just for fun. With the shower of sparks and such it was hard to follow the line too closely. Do you typically get close and then use a bench grinder or something to get closer to the final shape?

I think I may try my wet saw next time and see how that goes. Does anyone know what type of blade works best in a wet saw for cutting steel?

After that I'll probably try the band saw. I am guessing that the band saw may be the overall easiest, but I wanted to try some of these other ways first.

What about using a plasma cutter? Does the heat get too high and potentially screw up the knife steel?
 
with a plasma cutter give yourself a little room as you'll have to grind down all the slag at least 1/16" just for clean up from cutter..

for angle grinder just mark your pattern the width of a 'marks a lot' marker, say 1/4", this will give you a fat guide in which to follow.. just buy some thin cutting wheels from the big box stores and you're good to go..

never heard of a wet saw for metal..

good luck
 
Thanks Battle Creek. Someone just the other day posted something about using a tile saw for cutting knife steel. I have one and thought it might be worth a try?

When you have that extra with the angle grinder, how do you get down to where you actually want to be? Bench grinder or file it all?
 
I hog a lot of my material with my grinder, however with a angle grinder after its cut with a thin cutting disc you could use a thicker grinding wheel where you use the top side of the wheel place it against the metal and grind/sand it down to where its close enough... but if it were me, just get close enough where you can rough profile the rest with a grinder, files, or whatever..
 
I'm like Rob, standard sharpie traced around my pattern then I cut to the outside of that line. If in doubt I stop short. I don't try to really follow the line that close, just enough to make profiling with the grinder fast to reduce wasted time and belts. Any inside curves wind up a series of triangles cut down as far as I can then on to the belts. I used to grind more with the belts, but found that even with 36 grit belts a couple extra minutes arguing with the angle grinder and repositioning things in the vice were more efficient.

I'd say there's probably anywhere from 1/16 to 1/8 extra to be ground off, sometimes more at a tricky spot. The only area I can see myself cutting closer if I had a band saw would be the inside curve of the handle. The other big improvement would just be the amount of time required and the ease of cutting a blade out of a larger chunk of steel rather than a bar that's about the right width to start with.
 
I want to make sure I am getting this right. Cut out the rough shape with the angle grinder with a cut off disc, and then use a grinding disc in the angle grinder to get it closer. I don't have a belt grinder/sander. Is that the preferred way to get the knife really close to final shape? What about a bench grinder, would that be any quicker/easier than using the angle grinder?

Would it be worth it for me to try a belt sander to see how it works out? I'm not talking about going out and buying a Balder or something, but maybe try the Harbor Freight unit or something?

Any advice or thoughts genuinely appreciated.
 
For profiling, the bench grinder will get you the next step closer. Rough cut with the angle grinder. Smooth out the profile with the bench grinder. Finish it off with files.
 
I am a newb but here's how I did my first one with a 19 dollar angle grinder and a 30 dollar belt (w/coupon) grinder 1 X 30 both from harbor freight and a drill.

Trace pattern on with sharpie. Get a decent size (1/8) titanium drill bit and drill a series of holes around all curves. Use angle grinder to cut through the middle of the holes - and off any big chunks that are a nice straight line. Grind up to the sharpie line on the 1 X 30.

Pickup tons of the CZ 60 grit belts at HF as their only like a buck or two for QTY 2.
 
Thanks for the additional info jkf96A and Ryanol. I have a 4" angle grinder and a bench grinder. I think I am going to pick up one of the belt grinders from HF and try that too.
 
It works alright, takes a long time to do any bevel work but it's alright for handles and sharpening....it's a slippery slope and soon you'll find yourself checking Craigslist daily for an upgrade.

Good luck.
 
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