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mr drinky
12-30-2011, 11:40 PM
I have to spec out a custom suji that I am in line for with Devin, and I want to get a feel for geometry first. For a non-knifemaker who doesn't have steel, grinders and belts galore around does anyone have any low-tech suggestions for making prototypes to work out an ideal profile? I think Dave used cardboard for his prototype knives.

Anyone have a tips to make this process better?

k.

Marko Tsourkan
12-30-2011, 11:46 PM
I use a carboard cutout to get an initial reference, and then profile a blank and keep making adjustments until it looks OK.

Wood would be better than carboard, but you need to profile it still. If you want, send you your outline (email attachment is OK) and I will profile it on a piece of wood. I can send you a wooden profile for 250 suji along this one.

M

mr drinky
12-31-2011, 12:00 AM
Thanks, I may take you up on that. And if you have already done the 250 prototype for my knife, then sure, send it on. My Devin suji is going to be 270 though. I do have a belt grinder, so I will probably take a whack at it myself too.

k.

PierreRodrigue
12-31-2011, 12:03 AM
Go to a hobby store, pick up a piece of balsa or bass wood, you can rough it with an exacto knife, and smooth it with sand paper to profile.

Marko Tsourkan
12-31-2011, 12:11 AM
+1
Use a granite or glass lined with sand paper to get a nice profile on it.

M

SpikeC
12-31-2011, 12:29 AM
get a thin sheet of granite and an angle grinder. you don't want your template flexing on you, now do you?

mr drinky
12-31-2011, 12:39 AM
How thin do you get it? I actually live in one of the granite centers of the US, so rock is plentiful. My small town actually supplies a lot of granite for the monuments in DC.

k.

Marko Tsourkan
12-31-2011, 01:09 AM
How thin do you get it? I actually live in one of the granite centers of the US, so rock is plentiful. My small town actually supplies a lot of granite for the monuments in DC.

k.

No, granite or glass for a flat surface, so you glue some 80 grit sand paper on it and put a nice profile (heel to tip transition) on your balsa knife. You would be cursing me if you try to put a profile on a granite blank.

M

Eamon Burke
12-31-2011, 01:12 AM
Basswood.

mr drinky
12-31-2011, 01:16 AM
No, granite or glass for a flat surface, so you glue some 80 grit sand paper on it and put a nice profile (heel to tip transition) on your balsa knife. You would be cursing me if you try to put a profile on a granite blank.

M

Yeah, I understood that, it was just how spike phrased it that it sounded like he was profiling granite, so I was curious.

k.

PierreRodrigue
12-31-2011, 01:17 AM
Another thought on this, once you get the shape to say 90% done, give it a coat of CA glue. Balsa is so soft, the glue will stiffen it up a lot and give your profile clean sharp edges.

mr drinky
12-31-2011, 01:26 AM
That's a good idea. Is there a specific type of CA glue that would coat better? I could imagine balsa soaking things up pretty well.

k.

PierreRodrigue
12-31-2011, 01:48 AM
Any ca is fine. Medium viscosity might be better, or a couple coats of thin. Just get cheep stuff for that purpose.

Dave Martell
12-31-2011, 02:21 AM
I used regular cardboard because I'm up to my eyeballs in the stuff but it's not the best way to go. I think a better way would be to draw on some thin notebook type cardboard (there's a real name for this stuff that eludes me at the moment) and do the re-dos on this material and once satisfied go to sheet metal for a template for refining and tweaking.

PierreRodrigue
12-31-2011, 02:58 AM
In all honesty, I got a small sheet of 1/8" Lexan (plexiglass) for anything I want to turn into a template. I had enough in a 3' X 3' sheet for over 30 templates.

jmforge
12-31-2011, 11:56 AM
Some knifemakers use mild steel, but that is usually for "permanent" templates.

SpikeC
12-31-2011, 04:11 PM
It was a lame excuse for humor............

SpikeC
12-31-2011, 04:13 PM
I have some scraps of 1/8 hardwood ply that I use.

EdipisReks
12-31-2011, 04:36 PM
you should probably forge and grind a piece of your choice of steel into the profile you want. better heat treat it too, so that Devin knows exactly what to make.

Marko Tsourkan
12-31-2011, 04:39 PM
Good idea.

El Pescador
12-31-2011, 04:50 PM
Devin makes a good knife...everytime he's told me to "trust him" the result has been amazing.

tk59
12-31-2011, 09:17 PM
Cardboard works well but I have to agree with Pesky on this one and I'm not the trusting type.