Does someone make a grinding jig?

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amc5

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Hope this is the right place for this. Working on my first knife. I have ran across many issues that I have tried to fix. Main issue so far, getting an actual decent looking bevel/grind on the blade. I made my own jig. I am using a 1x30 cheapo belt sander from Harbor Freight (which may be the issue) and just doesn't seem to be working. However, it could be me. The top line of bevel doesn't get straight across. Kind of goes up and down. The blade itself also doesn't look to smooth. Looks as if i put the blade against the belt at 4 or 5 different positions. I know that may be hard to picture.

I think it may be my jig. I cannot do it by hand yet. Current jig is just a piece of metal shaped like an "L" with a few bolts in the rear to tilt it back or forward. Just been attached the blade on the front with a vise type tool. Maybe it's because the knife may not be in the right spot on the front of jig?

Thanks for your help.
 
Google "Fred Rowe Flat Grinder's Bubble Jig".

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Best advice though is to practice, practice, and practice some more. Almost no one grinds a pretty first, second or third blade.
It takes time and ultimately you'll want to be able to grind free handed. Watch here for applicable pointers:
http://www.youtube.com/watch?v=EPYtMd7vKjY
 
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My bet is inconsistent speed moving the knife across the belt, and maintaining equal pressure against the belt. Where you go slower or press slightly harder, more metal is removed.
 
I can see how it could be pretty hard to get flat bevels with a 1x30. I doubt the jig would help.

Might be better off using a good file if the steel isn't hardened.
 
Fred Rowe's jig is great (I just picked one up just a few weeks ago), but you won't have enough room to use it on a 1X30. In your situation, I'd hold off on buying it until you upgrade to a 2X42 or larger.

I had the same 1X30 setup until quite recently. Like you, I made a simple jig by clamping the blade to a piece of angle iron. You may want to add a pin or small bolt for the spine of the blade to rest on, then align the straight portion of the blade (assuming you have one) to be parallel to the top of the angle iron so that the grind will be more or less consistent when you change sides (you will still need to switch back and forth a few times get a consistent height). When you do the tip and belly portion, you'll learn to pull the handle slightly towards you do get the distal taper.

That said, it is difficult to flat grind with the 1X30. The platen is pretty flimsy and will bend with too much pressure (not to mention you'll bog down the motor without any effort at all). The table wants to move no matter how hard you tighten it. Also, the 1" belt width doesn't give much stability; you can rock back and forth against it and get gouges if you're not paying attention. If you want my suggestion, hog out material with a coarse belt, then finish with a file.

Finally, a trick to hide your mistakes on the 1X30. If you just can't get a consistent flat, do a full height convex. Glue a some padding to the platen. I've used a couple of layers of thin wool felt. Make sure you use real wool, polyester will melt with the friction. This padding puts a slight convex on the blade and also blends away those hesitation lines that come from inconsistent speed and pressure.
 
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Here is a link to a youtube vid that shows how a very effective one is made. https://www.youtube.com/watch?v=iNVFZC3FOkI&feature=c4-overview&list=UUvaetZD7fKoI6XgLtKXYoeA It's easy to make and it works great on a 1X30 once you get used to it (same thing with a 2X72) you will want to make a longer work rest for the sander though. I also agree that the bubble jig is a great tool that teaches you the muscle memory to do grinds free hand as well as makes keeping the same angle for the bevel alot easier.

-Paul
www.youtube.com/Lsubslimed
 
Thanks for all the great responses. ThePerpetualNovice, you hit it right on the head. I am having all those issues. I even installed a larger table. Just a 6x10 piece of metal. I have had it for 2 weeks and stuff is already breaking. Not to mention its loud and I think the largest belt wheel is about to fly off! I will look at the platen trick for sure.

I am usually pretty handy with making things. However, I have watched many hours of videos on knife making and no matter how hard I try, I cannot get this knife blade right with this 1x30. So, I am glad you guys said it may not be me haha. I am sure you guys see tons of newbies and same problems. I will have to save up and get something better. May not be a $1k grinder but better than this thing!

I will check the other info you guys posted. Thanks
 
While it's definitely hard to get a nice even bevel on the 1x30, it's possible to still get a nice grind. I did all of these on my 1x30 from HF.

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grizzled gizzard said:
I can see how it could be pretty hard to get flat bevels with a 1x30. I doubt the jig would help.

Might be better off using a good file if the steel isn't hardened.
Click to expand...

Fred's jig teaches muscles memory and helps you keep the blade level when grinding so you can match both sides, of course it WOULD help.
All it takes is practice. I started on a 1x42 before I got a kmg and I got great grinds with it. Like anything else it takes practice and hard work. You aren't just gonna be awesome at it out of the gate. This was done on a 1x42. It's the last one I ground before the kmg was delivered.
730ED6D5-8486-4F6A-B2A9-7B2C6F82283E-7546-000005DEED28F188_zps5e6a25a8.jpg
 
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my first grinder was the HF 1x30... I ground my first few knife shaped objects with it, it worked great for what it is and I still have it today..................and use it from time to time for various things.... never had a problem with it

I started off freehand as I feared being a slave to the jig, now scandis... that's another story...
 
I would think the platen on the 1x30" may flex not allowing the jig to be parallel to the platen face. Something to check anyways.
 
I agreee with above, on a 1x32 belt grinder, using a backing with slight give makes great results. I used a thick, firm leather strip for it that I doubletaped to the (flimsy) platen. Easy to remove but stays on when in use.
 
Thanks I will look into that Platen trick. Already looking for my next grinder! Maybe a 2" this time. Anyone like 4" or 6"?
 
If you are upgrading I would go 2 inch, and preferably 2x72. The selection of belts relative to the cost is huge. It will be harder and more expensive to get good ceramic belts in different grits for a 4 or 6. That's not even taking into account j flex belts or scotchbrite belts.
 
I was thinking of getting one of those bubble jigs. If it's anything like sharpening with a guided system then it may work well as a training tool for noobs. I was terrible at freehand sharpening until I got proficient using a lansky and a sharpmaker. I feel like those two tools gave me a feel for it and now my best edges come freehand. You got to figure that your muscles will get used to the correct movement jig or no jig so once you take it off you'll be better then just starting with nothing. Sort of like training wheels lol
 
I personally went with the bubble jig rather than a sled style jig just because I wanted to have a training tool to improve free hand grinding rather than a crutch that would make nice grinds but still leave me high and dry when a complex grind needed to be done freehand. I have noticed a significant improvement in my bevels since starting to use it, and the clamp is super handy with it as we'll.
 
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