How to fix this grind?

[Maelstrom78]

I'm assuming I can try to take more of the "middle" of the more properly ground side? There is a little more than a dime thickness left on the edge.

I'll have this guy wired and reversible after this weekend.

Should I just take both sides back on the disc?

Thanks.

 

[William Schrade]

First thing you should do before grinding is apply Dykem on both sides and scribe your lines with a caliper so you know where you are. You can get a cheepo at HF for around $20.00.

 

[i4Marc]

I would say you'll have to bring the grind up the side of the blade to even the sides. If you want the top of the bevel to follow the curve of the cutting edge, taking more middle out of the left side won't work. To get the line to come up on the right side at the plunge you need to put more pressure there. Go slowly. Take small nibbles until you get the feel for it. Just keep a neutral to top-leaning pressure on the belt so you stay away from taking any more material off at the edge. Push in, start moving the blade and then feather off the pressure. Like people say, grind your weak side first until you get the line you want. Then it will be easier to match with your more confident side.

 

[Maelstrom78]

Thanks guys. I've been using the bubble jig to try to speed up the learning curve. But I haven't scribed the grind lines, only the edge line. I'll try that.

So I'll try to "flatten" out the"good" side to try and match the other.

It's interesting that the more I grind the more I see the failings of my previous ones. I don't think I'll even send them out to HT, just handle practice I guess.

 

[i4Marc]

There is plenty of meat left on that blade to make your corrections. Stick with it then send it out for HT.

 

[Maelstrom78]

There is plenty of meat left on that blade to make your corrections. Stick with it then send it out for HT.

Ok I'll post when I have done that. Hopefully with that correction I will take out the filing for the plunges as well. I don't think I filed them too deep but it will be a close call. And if it is then I'll claim it worked out just like I had planned!

 

[tryppyr]

I believe what you are discovering is that you have one dominant/strong hand, and one weaker and less skilled hand. How that affects your grinds will depend on a lot of things, not the least of which being your awareness of how your hands differ in terms of how they apply pressure, how accurately they move, and how to compensate for the differences.

This is one of the reasons when using a grinder I use a light touch and pause to check the result of each pass on the grinder before and after dipping it in water. By using a light touch you limit the amount of damage any one pass will make to the end result. By checked the results after each pass you get a much clearer understanding of what your hands are doing. Using tools and jigs is fine, if that's what you want to do, but you need to also rely on your eyes and your hands. So learn the basic free hand grinding skills first.

Once you develop "the touch" you can begin to move through the projects faster. But don't be in a hurry to do so. Really take the time to figure out how to use BOTH of your hands to the best effect.

Also, find a system that works for you. For me, that means make one or two passes on one side, then flip it over and make the same number of passes on the other side. This helps in two ways. First, if you're doing it right it helps to keep the amount of material removed from each side consistent with the other side. but secondly, if you aren't doing it right you will see the differences in time to do something about them. Generally, the differences will show up as a bevel climbing up the blade faster on one side than the other... or grind marks appearing in the flat on one side (where they shouldn't be). Pay attention to these, as they are clues that your bevels are getting out of sync. Make adjustments and teach your muscles how to make consistent bevels.

Good luck and have fun with this.

 

[Maelstrom78]

Great advice. I wasn't switching sides as often as I should have been. I have to say that I can see progress from each attempt. This is number 5 I believe and I am learning something each time. I think I should get some less expensive steel though. So far I am learning on $80 154CM where admiral steel has some 1/8" 1095 for much cheaper. Heat treating that is more challenging but I will be sending out for a while anyway.



So:
-Dykem (You can see the little white bottle in the pic by my gloves so no excuse for not using it on the flats)
-Take my time and switch sides often
-Light touch
-Non dominant hand primarily and then dominant hand to try to match

I don't have a work surface on my 2x42 Craftsman so I am pretty much freehand except for some guidance from the bubble jig. I agree that developing the freehand skills is worthwhile. Should I think about putting the work surface back on? It was a POS that was difficult to get to stay in one angle so after I hacked the side off to get the belts on and off easier I just took the whole thing off.

A question about grinding to a scribed line: What if the edge is still to thick when I am up to the scribed line? I assume that I just go back and grind at a less obtuse angle then correct? Eventually you guys must have developed the skill to just understand at what angle to grind to get the grind line you want with a certain thickness stock.

Good point too about keeping it fun too!

 

[Stacy E. Apelt - Bladesmith]

What I do when that happens is "walk" the top flat on the over cut side forward.

Put the blade on a grinding magnet with the good against the magnet. Set the bad side on the flat platen, disc, or surface plate and see how you want to hold it so the front of the bad area moves forward. You will grind the whole tang/top bevel at one time, thus keeping it flat. You apply slightly more pressure toward the tip so the facet walks that direction. You can do this on a sheet of sandpaper taped to a granite surface plate, or on the grinder. If the grinder isn't VS you might be best to try the sandpaper first. Once you have figured out how you will hold and grind things, turn on the grinder and carefully grind the tang and top flat surface of the blade so it walks the flat forward. Take gentle and short bites, as the facet may walk forward fast.

Once you have moved the flat surface forward enough, touch up the bevel grind as needed to make it match the other side.

 

[Josh Mason]

my 2x42 Craftsman

This is probably more than half of your problem. This machine is too fast. You have some pretty nice bevels cut with it though. What kind of platen setup do you have? Any unevenness in your platen will transfer to your blade.

 

[HallHandmade]

If you have trouble you can always grind your weak side first, matching the other side is a breeze.

Now I just kind of grind however the heck I feel like, and sometimes I pay for my false sense of security from being comfortable with my machine and technique.

 

[12345678910]

On the left side, you created a curved grind line by either moving the tang up and down, or spending more time on the ends than you did the middle.

On the right side, you pulled it straight across at an even pace.


Whatever it is that you do, you have to do the same on both sides.



On a fixed speed grinder, use a much finer grit belt like 400 or 600 and it will go much slower.

 

[Joe Watson]

whatever it is that you do, you have to do the same on both sides.


.

This. No reason in typing it out because it'll only add confusion. But pay attention to things like your stance, how you're contacting the platen, etc. as you switch sides.

Check to make sure that your platen on your craftsman is flat and not canted. Most of them are canted, so you'll need to bend it into place or mount the entire machine so that the platen is straight.

A ceramic glass platen will take care of any dishes, the completely flat and smooth surface will greatly help you with tactile feedback.

You may also find that your grinds will be better post HT.

Don't feel like you need the Bubble Jig. I've seen it help folks, and also hold others back. Up to you to determine where you're at!

Keep messing around and find out what works for you!

 

[Maelstrom78]

What I do when that happens is "walk" the top flat on the over cut side forward.

Put the blade on a grinding magnet with the good against the magnet. Set the bad side on the flat platen, disc, or surface plate and see how you want to hold it so the front of the bad area moves forward. You will grind the whole tang/top bevel at one time, thus keeping it flat. You apply slightly more pressure toward the tip so the facet walks that direction. You can do this on a sheet of sandpaper taped to a granite surface plate, or on the grinder. If the grinder isn't VS you might be best to try the sandpaper first. Once you have figured out how you will hold and grind things, turn on the grinder and carefully grind the tang and top flat surface of the blade so it walks the flat forward. Take gentle and short bites, as the facet may walk forward fast.

Once you have moved the flat surface forward enough, touch up the bevel grind as needed to make it match the other side.

Interesting. I was probably reading here (maybe even from you) that grinding tip up (if I am understanding you correctly) is a commonly underdeveloped skill. I think I might try on the paper and then the disc before braving the belt. If it creates a noticeable taper then I would do the same on the other side and then regrind both bevels. I take heart that even the masters have to know ways to fix things. Thanks much for the direction.

 

[Maelstrom78]

This is probably more than half of your problem. This machine is too fast. You have some pretty nice bevels cut with it though. What kind of platen setup do you have? Any unevenness in your platen will transfer to your blade.

Thanks, other than the bevels not being even I am halfway pleased with the grinds themselves. I have a flat ceramic piece that I had cut to fit the platen JB welded on for a platen.

 

[Maelstrom78]

If you have trouble you can always grind your weak side first, matching the other side is a breeze.

Now I just kind of grind however the heck I feel like, and sometimes I pay for my false sense of security from being comfortable with my machine and technique.

Hey just a couple in and I learned how to multi-quote! Sorry about the above replies. Yeah I think the bevels were even and then just one firm pull on the left side....Shoot!

On the left side, you created a curved grind line by either moving the tang up and down, or spending more time on the ends than you did the middle.

On the right side, you pulled it straight across at an even pace.


Whatever it is that you do, you have to do the same on both sides.


On a fixed speed grinder, use a much finer grit belt like 400 or 600 and it will go much slower.

I think you are right. I did a firm pull on a 80 grit belt and it straightened out that one side. So maybe after I hog off the sharp corner go right to the higher grit belt to slow the process down? That makes a lot of sense thanks.

This. No reason in typing it out because it'll only add confusion. But pay attention to things like your stance, how you're contacting the platen, etc. as you switch sides.

Check to make sure that your platen on your craftsman is flat and not canted. Most of them are canted, so you'll need to bend it into place or mount the entire machine so that the platen is straight.

A ceramic glass platen will take care of any dishes, the completely flat and smooth surface will greatly help you with tactile feedback.

You may also find that your grinds will be better post HT.

Don't feel like you need the Bubble Jig. I've seen it help folks, and also hold others back. Up to you to determine where you're at!

Keep messing around and find out what works for you!

I think the ceramic is flat...but it is just a cut piece from a Home Depot tile. I'll check to see if the entire platen is somehow tilted left or right.

 

[Salolan]

I think the ceramic is flat...but it is just a cut piece from a Home Depot tile. I'll check to see if the entire platen is somehow tilted left or right.

Did you spend any time making it so? Some serious flattening on a granite surface or disc grinder? If you didn't I will almost guaranty it is not flat. I spent a few minutes truing mine up... wasn't nearly enough. I think I would have been happier with just the 3x3 angle I made my platen out of before I glued the ceramic to it.

Chris

 

[Maelstrom78]

Hmm, in that case then no it's probably not that flat. I saw a Link at one point here that had relatively inexpensive glass platens. That would no doubt be superior to what I have.

 

[Maelstrom78]

So with the disk I got it closer going slow and steady.

 

[Daniel Fairly Knives]

Looking good!

If I have a low spot in a bevel I literally push harder at that point, usually after a few passes I feel it straighten up.