Bevel issue

Most often it's just what you said but worn out belts or a worn platen - not much by the way will give the same results.
Frank
 
You will NOT I repeat Not create good grind lines if this is for first or probably 10th time trying. Get some mild steel at the local hardware and a bunch of 60 grit belts to practice with !
Frank
 
if the blade is flat, probably those waves are due to uneven strip passages. This means that in some places do more pressure than in others and also that you approach the tape with the blade in a non-perpendicular way.
 
mknife has the answer - even with the blade flat, using a jig, there is still a pretty good learning curve to holding the same pressure on blade for the full cut, not only same pressure, but same speed for the full length. The same pressure MUCH be held with BOTH hands holding the jig. The jig will provide only the same angle, not even pressure for grinding.
 
I used to grind with a jig on my 1x30. I found it worked well as the belt isn't very wide, and free-handing on the small 1x30 platen would be a tight thing to do. I tried using the same jig on my 2x72, and it felt like I was fighting and correcting the bevels constantly. I made about 10 knives this way.

I recently started free-handing, and I can't believe how much more control I have. You should try setting the initial bevels with your jig (like you did), and then try free-handing on the higher grits (120, 220, etc.). Flat grinding isn't to difficult once the initial bevel is put in. Its easy to match it. You should be able to pull out that waviness.
 
Jigs are something a lot of new guys look to ....I did when I was new a few years back....BUT jigs are limited you are much better off going to get a bunch of cheap mild steel like frank suggested....eventually a lot of it becomes muscle memory just like riding a bike. When I started I wasted a bunch of time with various different jigs and all I found out is that a lot of things can only be done freehand...just takes practice. Also the flatness of the steel is also key. when I learned freehand even if the steel wasn't flat eventually I learned how to compensate for that and even things out....eventually I got a surface grinder. Not for this purpose but it actually REALLY surprised me of HOW UN FLAT the steel was. I thought it was at least close to perfect....nope not even close (unless what you buy is PERCISION ground) I started cleaning up blanks on the surface grinder before doing the bevels and it sped things up ALOT because now I did have to compensate and even things out constantly.....in short learn freehand is number 1 number 2 is get flat steel or learn to even things out by hand as you go
 
i found it was easier to put too much pressure on one side of the platen than the other when using a jig. it takes away some of your feel. that makes the top of your grind line wavy. speed consistency pulling the knife across the platen and pressure also play into it. the hard part is figuring out which of the 3 is contributing to the problem :D
 
nyknife said:
Jigs are something a lot of new guys look to ....I did when I was new a few years back....BUT jigs are limited you are much better off going to get a bunch of cheap mild steel like frank suggested....eventually a lot of it becomes muscle memory just like riding a bike. When I started I wasted a bunch of time with various different jigs and all I found out is that a lot of things can only be done freehand...just takes practice. Also the flatness of the steel is also key. when I learned freehand even if the steel wasn't flat eventually I learned how to compensate for that and even things out....eventually I got a surface grinder. Not for this purpose but it actually REALLY surprised me of HOW UN FLAT the steel was. I thought it was at least close to perfect....nope not even close (unless what you buy is PERCISION ground) I started cleaning up blanks on the surface grinder before doing the bevels and it sped things up ALOT because now I did have to compensate and even things out constantly.....in short learn freehand is number 1 number 2 is get flat steel or learn to even things out by hand as you go
Click to expand...
Send me pic of the surface grinder
 
A couple things to check like others have said:

1. Your billet doesn't look like it is flat or has been flattened.

2. Your jig and or workrest is not flat.

It's not the belt. It can be pressure but it is easy to correct that. A simple way to check if it's pressure is out a parallel guide and use your jig.

I would tell you to try it freehand but I don't think that will help. If you can freehand you will be able to tell real quick if it is the jig/rest or the billet.
 
Sharpe5097 said:
1. How do i flatten the billet.
Click to expand...

Ideally you would use a surface grinder for real precision, but suitable results can be had by holding metal again your flat platen and grinding flat. It helps to hold metal with a magnet. You'll see the belt grinding full length of the metal, and will be fairly flat.
 
If you are into manual labor you can draw file it, then use a sheet of sand paper on a granite block to finish up. Doesn't leave a "precision ground" finish, but it'll be pretty flat if you don't mess things up too bad.
 
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