profiling and grinding question

blgoode

blgoode

Knifemaker / Craftsman / Service Provider
Joined
Oct 3, 2003
Messages
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I need some help on what you guys do. I am cutting my knife out of flat stock...cleaning up everything with watever seems to work. I wish I had a spindle sander but I am using wood dowels with sandpaper...
Here is what I am having trouble with.

I am freehanding my grinds right now. Do I need some sort of rest or it this a good way to learn. I think I tried to grind too fast on my current blade for frustration of not being able to see the surface that you are grinding. I have a verticle 2 x 42 grinder.

What are your steps from paper to finish grinding?

Thanks for your input....
 
I don't believe I was able to keep up with you on that question but:

The short responce is using the vertical grinder is a matter of feel and sight. I can not see the surface either and the way I do mine one side is edge up and one side is edge down, which is not how a lot of others more experienced than I do it. Aside from such particulars, it has much to do with developing a feel for it based on your experience at it. Getting the angle with a belt grinder will come. Just grind and be sure not to break the spine with your bevel. I broke several not too long ago. It takes me a good while to grind a blade but each one seems to take less than the last. It will come and by all means continue to do it free hand.

RL
 
I am still fairly new to knife making but will tell you what works for me.

I start by grinding the scales off the barstock. I usually take it down to 220 grit and then handsand the areas where the ricasso and plunge will be to remove any scratches left by the coarser belts. I do this to mimimize sanding after the blade has been profile to reduce rounding of edges. After I cut, profile and scribe parallel lines on the blade edges I go back and touch hand sanding up a bit to remove any scratches. I should note that I used drum sanders for the radii. I usually also drill the handle holes at this point.

Once I have ground the bevel (I grind with edge up so that I can see the scribed lines) I Heat treat. I usually take my blades almost to finished thickness with a 60 grit ceramic belt prior to HT. Once they are treated I run through the finer grits and handsand the bevels and finish the flats.

I uses a couple of wood block with glass epoxied to them for sanding aids. They help to keep everything flat.

Hope this helps

Take Care
Dean
 
I grind edge up on both sides doing only a couple passes on each side at a time. I do this free-hand and though it may be frustrating, I think you'll eventually like doing it this way better than relying on a jig or tool rest. You could use "blade stops" which are basically two pieces of steel that you bolt clamp where you want your plung grinds to start. This is a good way of getting your plunges set and even. Then once that set (usually at 50 grit) you can take them off and take it from there. Most of it is practice though, like anything else, the more you do it the easier it gets.
 
I should also add that I too grind free hand without any aids (something that I thought would be near impossible for me...:D). I flat grind almost all of my blades and at first it took me hours to get a bevel ground. I found the most difficult part was to get the "Flat" established enough so that I can follow it and change it as needed

I used to run my grinder on a very slow speed. I now run my grinder on its fastest setting and can grind a bevel much faster than when I began. As an example I ground a 9" blade this weekend and it took about 45 minutes to complete the bevel to the point that I sent it to HT (about 0.030" at the edge). This is still likely slower than most but I too am just learning and will be for many years to come...

Take Care
Dean

edited to correct spelling...:rolleyes:
 
J. Neilson



I have a question dealing with your post, and well as on this general subject.

First Im going to tell you what Im doing now, and where Im having trouble, then I like you to tell me if you understand what I am doing, and what you do in the same situation, okay, here we go.

(Remember I have had not even one knife-making lesson, I have no teachers except for you guys on this forum)

After forging to rough shape.
After profiling the outer edge line.
After flat grinding.

At this point I take a can of black spray paint and paint the edge of the knife in the area where I will be both going with the file for the guard, and the Ricasso and the plunge grinds.

I then mark out where I want the guard to stop at.
I measure over from the guard mark about ¾ of an inch and scratch in the paint in the edge where the plunge cuts will be at.

Now I hold the blade edge UP and slack grind but I stay away from the mark where the plunge will be by about ¼ inch until I have grinded off a lot of the extra steel.

Then when I got the sides of the blade about as far as I dare take them with the 36 grit belt, I slowly sneak up on the scratched plunge marks with my belt.

I work over to it and then blend things so they look nice, then bump up to the next belt like 100 grit.

THE PROBLEM: I always end up with a dip after the Ricasso. Just at the actual start of the cutting edge my knife seems to always take a dip up then go back to the rest of the knife cutting edge line.

Now I know that if I ground my blades with that type of "Notch" that is seen in knives that this problem might go away, But I am trying to use the knife design that Ed Fowler shows in his movie where there is no notch.

Any ideas what Im doing wrong?

THE 2nd PROBLEM: when I and slack belt grinding my knife, flipping on both sides, back and forth, I always seem to end up with a knife that looks like I took too much off one side, and the blade looks bent.

The problem is that to fix this bent look I have to take more off the other side, and thus I have a huge battle going on and one thing fixed means another thing is now off a bit.

Ever happen to you?
 
blgoode... like J. i also free hand grind...imho,its the only way, just take it slow, and establish where you want your plunges, scribe in your centerline and start grinding brother!
i now only hollow grind on a 14"wheel cause,
i HATE FLAT GRINDING!!!:barf: :D
i also started on a 2x42 grinder, slack belt grinding was tough for me too,so i started using the small platen it comes with.. making sure that you track the belt over the side you are grinding on to get your plunge cut nice and smooth...
and i found it easier to sneak up on the plunge cut when i did it that way...taking and even amount of material off on both sides a little at a time... i also used a push stick to keep even pressure on the blade when pushing on the platen... when trying to raise the grind,i use my thumb pressure on the blade moving it toward the spine on each pass to get the height of my grind where i want it
(grinding edge up,on both sides)... its tough for me to try to explain,to you how i do it, but i hope this helps :)
 
I also grind free hand,using the edge up then edge down method,never have been able to grind a blade prperly with the edge up both ways.
The stop block works great when doing the ruff grinding.Then I eyeball the rest from there..

DaQo'tah Forge--You are trying to hard at the plunges.I mean when you are trying to get them evened up you are not keeping the grind going though the whole blade,in other words you are staying in the grind at the plunges to long..To fix this just grind the edge of the blade through the ricasso length wise on the flat platten then start your grind in the middle of the blade and slide back for a quick bump at the plunges and then back out to the tip.

Bruce
 
Bruce hit it right on the head. You have to hit that plunge and keep going. You don't have to make full passes each time either. If you hav a dip or rise to fix you can to a short pass and even it up as you go. I had that same problem starting and the was all it was, sitting in the plunge cut too long and soetimes just a second it too long. As far as one side and the other being off...are you keeping the bevel even as you go or counting the passes. I use a marker on the edge and scribe a center line but, only grind about 60% before HT. I keep the amount of metal taken off each side as even as possible before HT but, after keep you bevel lines even, even if it seems like your making more passes on one side than the other. You may be holding the blade differently or leaning a certain way without even noticing it. Just take it slow and it will all even out at the end.
 
I am hearing everyone load and clear!! I have a piece of material to add to my Platient....thanks for the hook up J. Neilson..

I think I was in too much of a rush this weekend and my plan aof attack wasn't well rehearsed if you catch my drift. Too little time measureing here and there and a little too much time grinding but hell. Experience is the key.

I am grinding edge up and do notice I favor one side over the other.
How thick should I grind till ht? I think that is frustrating me as well....the not knowing part.

Just got my first batch of micarta linen and canvas in today. Now I need to get busy ;)

Do I rough up the micarta before epoxy? I am thinking dugh...but thought I'd ask.

Thanks for the help guys.
 
Try leaving 1/16 inch at the cutting egde for thicker blades before heat treat,this is something you will need to experiment with as you grind.What works for one maker doesn't always work for another.You can ask 100 makers a question and get 100 different answers as everyone has there own ways that work best for them,that is the cool thing about knifemaking,other than the steel there really isn't anything set in stone that you have to do a certain way.Infact this is how things get figured out,usually by a beginner that doesn't know that it shouldn't be done that way according to others,but it worked and worked better than the other methodes if you get my meaning.Just try different ways of doing things and you will figure allot of things out as you go,don't be afraid to make a mistake,sometimes fixing them ends up in a cooler knife or lets you know that all is not a lost cause,just a set back that can be fixed...
Bruce
 
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