Show me your jigs!

[mrcairney]

I've been wracking my brain trying to design a simple jig that I can use for bevelling my forged knives on my belt sander.

It's one of those hand sanders that you can flip it on it's back and clamp it onto your bench. So I'm working out some bits and pieces the see what will work and what won't. Funnily enough, I'm missing the tool that I can check the angle with, something tells me this plastic protractor won't be good enough, so if you know what will help with that let me know. (I've got a bevel gauge, but nothing the match it with)

Anyway, if you bevel your knives in a similar way, show me how you do it. Perhaps I'm over thinking it.

 

[Whittler Kev]

Do you mean like these ones I make?
http://www.bushcraftuk.com/forum/showthread.php?t=74556&highlight=

 

[HillBill]

This is the kind i use. This one was my old set up, i still use the machine but i have a new fully adjustable jig of the same style. I also have a radiusmaster now that i'm modding to have a similar grinding set up.

As for testing your angles, get an old hacksaw blade, cut it in half, attach the 2 halves together with a small nut and bolt. For my set up i would lay one half on the belt and the other would go up the jig. Tighten the bolt and measure on the protractor you have. I expect you will know this, so apologies if i sound like i'm trying to teach granny to suck eggs, but the jig angle only wants to be half of the total angle you want your bevels at.

Edit, Wow can't remember the machine being this clean lol, its had some hammer for 3 years, its looking rough but it still works as well as it did when i got it.

 

[Whittler Kev]

Wow that is clean. Shame about the bench/floor

 

[HillBill]

Back then when i first started, i worked from a bench under the carport. The machines were just stored in the garage when i wasn't using them. It was my parents garage and full of all sorts of junk. So i had no room to work in there.

 

[mrcairney]

Hey guys, That's the type of thing Hillbill has there. I've made some progress so I'll take a pic in a bit and show you what I mean. The hardest part for me has been working out how to attach it to the sander.

It's funny you mention about only needing half the angle. I WAS working to a full 20˚ and thinking 'That can't be right!' *facepalm*. The reason for that was most of the info I found about making bevel jibs are from woodworkers and they only need one bevel on their chisels. Doh!

 

[mrcairney]

Ok, I took some pictures. (Ignore Workshop cat, it craves attention)

I knocked up a bevel finder using a rule and the plastic protractor and set it at 10˚


Then I placed the bit of right-angle I have at the right angle



The I marked out the angle onto the body of the sander. All I need to do now is work out how to attach the jig to the sander. I'll probably be able to make use of those screw holes. But I'm going to have to nip out and buy some nuts and bolts I think. I'll keep you posted.

 

[HillBill]

Can't you attach the jig to the vice instead? It may be easier that way, as long as the vice locks the sander in the same spot then it will work well. Also, bear in mind that you will have to take the belt off the sander and the jig will be in the way of that. Much easier to have the jig on the vice IMO.
20 degrees is a little shallow for knife bevel unless you plan on having a secondary or it is a dedicated blade for something. I make mine at 24, as this can keep a zero grind well enough, yet also works well with a micro secondary.

 

[mrcairney]

I think I need to re-think this whole thing. For what it's worth attached to that side the belt comes off easily, but I'm limited in that I can only use the existing screw holes for the sander. So it's far from ideal. Some form of vice mount would be better. I think I've got a ball socket vice somewhere...

Also in a test run, the spine of the blades I'll be grinding (small stick tang carvers/sloyd) are off the blinking tool rest before the edge even hits the belt! So all in all today didn't go to plan.

Hmm...

 

[HillBill]

Yeah you need to cut a section out so that the pate overhangs the belt at each side. I had the same problem with narrow blades. Which is why i redesigned it., You also need to bevel/chamfer the underside so that it gets as close to the belt as possible. Give me an hour or two and i'll take some pics and post em up to show you how it needs to be done.

 

[mrcairney]

Thanks HB. I can't help it'd be easier if I bought the right tool for the job!

I'd quite like the mount the sander vertically on the wall but let's get this sorted first...

 

[Everything Mac]

I recently made a bubble jig. It's not perfect but it's easy to do and works pretty well.

Andy

 

[mrcairney]

I've just been checking out Fred Rowes bubble videos weirdly enough!

 

[lannyman8]

hey Steve, i just use a bit of bent stainless that i had spare, i bent it 90 degree then screwed it into the flat work area of the grinder, then played with the angle by eye, its a good scandi ATM but could be moved for a flatter angle....

all the rest is done free hand, as are my convex and flascondi

 

[HillBill]

Here you go mate.

 

[mrcairney]

Thanks HB, those help loads. I'm going to get in the cellar and stare a solution out of it. Need to work out how to fit it to the bench, not the sander. I'll have to pick up some stainless plate in the morning, don't think I've got any

 

[HillBill]

No worries

It doesn't have to be stainless, mine isnt. Mines just some 6mm steel plate that a mate picked up from work for me.

 

[demographic]

Not sure about the rest but I have one of THESE bevel gauges for checking the bevel angle on chisels/plane irons and so on.
Kind of handy when I have things set up with different grinds for different purposes.

There's also one with a wider range of angles than the one I own HERE.

 

[lannyman8]

i just used stainless because its what i had, it wears a little better though than mild steel or un HT steel....

 

[lannyman8]

My very basic kit here...

Sent from my GT-S5570 using Tapatalk