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panch0

panch0

Joined
Jun 16, 2008
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Finally had a chance to work on my first knives. Started out with 40 grit to get the shape, then used 50 grit to do the flat grind, then used 400g, and finally the 600g by hand. Well when the light hits it you can see grooves from the flat grinding.:grumpy: Is there a special dance i could do or a spell that I could recite? If not then I guess I will start over with 120, 220, 400, and finally 600. Does that sound about right to you guys. Thanks.
-frank
 
Skipped too many grits on the first go round. Your second plan of 120 220 400 600 will work much better. Use good sandpaper as well.
 
Sand cross way when possible so you can make sure you get the scratches out from the previous grit. I plan my angles so the last grit will be parallel with the blade. If you are real carefull and look closely you will save alot of time and paper. Cut a sand paper backing out of wood or micarta or anything stiff you have (this works best for me about 1/4") glue on some leather and cut to fit. Helps save the paper and easy on the hands.
 
Patrickknives said:
Sand cross way when possible so you can make sure you get the scratches out from the previous grit. I plan my angles so the last grit will be parallel with the blade. If you are real carefull and look closely you will save alot of time and paper. Cut a sand paper backing out of wood or micarta or anything stiff you have (this works best for me about 1/4") glue on some leather and cut to fit. Helps save the paper and easy on the hands.
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So when you say angles do you start out with 120, then slightly tilt for the next grit up and so forth so that when you do the last one you are pulling the paper towards you by hand?
 
Looks like you are stopping at 600, I clamp the blade on a block of wood in my vice. the 600 grit will be use straight up and down the blade, so the 400 will be at a 45 from the right, the 220 will be straight and the 120 will be at a 45 from the left. I would start with the 220, 120 can do alot of damage unless you are taking out belt burns or deep file marks. I use wd40 as a lube but you can use water with a little soap as well. If I am finishing with 600 that means I will do my finish as 400, after the 600 I go back and draw 400 down the lenght of the blade to make my hand finish scratches. Just pull straght the full length, move to another new section of paper and pull again until you like what you see.

If you make sure you have all the scratches out at 220 it should only take a couple of minutes to finish the other grits, look at which direction the scratches are and that will tell you what grit you should be using.
 
Years ago on another forum I read one of the 'old timers' say, "water cuts, oil polishes." I've proven that to be true for me, so I use soapy water or more often (because it's handy) glass cleaner on the scratch removal grits and switch to oil for the final grit. I've found that I like the finish that oiled fine grit paper gives over dry paper. I've tried everything from Cool Tool II, to WD-40 to everyday 3-in-1 sewing machine oil on the paper, and - because it's handy - usually use WD-40. One final twist; I usually figure 600 is a good place to stop but sometimes I'll break my rule and go over that with -dry- 1500 grit paper. Not often though, because most of my knives are not 'nice' enough to make it worthwhile.

Also, for flat ground blades I most often use a palm sander with a micarta platen replacing the rubber that came on the sander. That cuts down the labor immensely for me, and more importantly -for me- is less likely to round off the flats than using a sanding bar has been.
 
simple rule is to double the grit each change. So something like 50, 100, 220, 400, 600 would be the scratch removal procedure. Scratches from the previous grit must be gone before the next grit is started....or they will show up in the final step. Changing the direction of each grit helps you see the old scratches from the new ones. Start with perpendicular strokes (to the blade), then switch to 60 degrees left, then 60 degrees right, then parallel to the blade. Once you pass 220 grit, and all the previous scratches are gone, you can sand only from ricasso to tip for the rest of the grits.
Stacy
 
So the scratch removal process is done by hand or with belts. I used up to the 600g belt then did the 600g from ricasso to tip. Just want to understand the right way to do things, and to get a decent finish on the blades. I appreciate the advise and keep it coming. Thanks.
-frank
 
You'll save a lot of time if you take the blade up as high as possible on belts then step back one grit for sand paper. I was taught to go to 600 or 800 on the grinder and then start hand sanding with 400 grit. 120 and 220 sandpaper cut the nicest, so I wouldn't stop at anything less than 220/240 on the grinder.

Your other option is to use stones before going to sandpaper. Deep scratches take too much time and paper by hand, imo.
 
I bounce back and forth between the grits on the grinder, I will usually go to 220 on the grinder and then start hand sanding with 220. Then hand the rest. My belt technique is not good enough to use the finer belts, just dont have the touch. The real key is to make sure you get the previous grit scratches out. If you see scratches and look at the angle you will know which grit to go back to, this saves alot of time and paper.
 
No-No-No, just go to 120, HT will mess up the finish so I dont spend much time. If you send it to a pro you will probably have less sanding when you get back. What type of steel is it and how do you plan to get the HT done?
 
When I worked in a body shop we cross hatched with each grit, To get as close to a "True Flat" of a surface as possible. Also the use of a "Guide Coat" will help immensly. I'll take a blue or red Sharpie pen (for lack of dykem) and coat the part of the blade that is getting pretty, and as you sand, it will show up your lows and highs. I'll cross hatch with soapy water to 100-220 for pre heat treat, then post H.T. 100-220-320-400 then sand parallel with the piece from there 600-800-1000 then buff for mirror. The cross hatch itself leaves a wonderful satin look to it once up to and past 400.

Jason
 
Patrickknives said:
No-No-No, just go to 120, HT will mess up the finish so I dont spend much time. If you send it to a pro you will probably have less sanding when you get back. What type of steel is it and how do you plan to get the HT done?
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I am using ats34 and will get them HTed at texas knifemakers supply, air quenched.
 
Thats good should come back pretty clean but I still would not put alot of time in. Just a few small decarbs and it will take a bit of sanding. I go to 120 with the belts and then send to HT. Start with a new 120 belt when it returns and see if I can finish the bevel without too much trouble otherwise I go back to 80. I grind down to about 0.060 before heat treat and the to 0.040 before sanding and sharpening.
 
Patrickknives said:
Thats good should come back pretty clean but I still would not put alot of time in. Just a few small decarbs and it will take a bit of sanding. I go to 120 with the belts and then send to HT. Start with a new 120 belt when it returns and see if I can finish the bevel without too much trouble otherwise I go back to 80. I grind down to about 0.060 before heat treat and the to 0.040 before sanding and sharpening.
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After ht is when the blade cannot get too hot. correct?
 
panch0 said:
After ht is when the blade cannot get too hot. correct?
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Hey panch0, I too am messing around with my knife making stuff, and right now I'm gathering materials to start making "real" knives. So from what I've read and heard, once the knife is HT'd, you shouldn't get the blade too hot, other wise you risk softening up the edge.

Good luck with your knife, this thread is helping me get some pointers too :D :thumbup:
 
batosai117 said:
Hey panch0, I too am messing around with my knife making stuff, and right now I'm gathering materials to start making "real" knives. So from what I've read and heard, once the knife is HT'd, you shouldn't get the blade too hot, other wise you risk softening up the edge.

Good luck with your knife, this thread is helping me get some pointers too :D :thumbup:
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Whats up bro! Make sure you post pics of your work in progress. This older fella here at work told me the same thing about letting the blade get too hot. I finished up with 220 last night and will be sending my blades for HT this afternoon.
 
As long as you stay below the temper temperature about 400f you are ok. Grind lightly and dip alot into water. With new belts I can grind quite a bit before the water evaporates off the blade. The real problem area is the tip. Watch the water, you will see it evaporate, when its gone bad stuff will happen quickly. Lots of water, slow speed.
 
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