Bleh... Plunge woes.

Yeah, it's become apparent that it just won't work. I tried tightening up the belt and had it grenade in my face just now.

x42... Right. Well that's what I get for trying to type when I'm tired.

Screw it (for now) I'm goin to bed.
 
Strigamort said:
I think it's worse in person than it looks in the pic.

The sides don't match up and it's just a dirty cut. The marker makes it look like it's ground straight up to the spine in the 2nd pic, but it's just the line drawn on the steel.

I wanted to ask for pointers before it got to a point where it would be hard to fix. From past experience I can see where this is going if I don't do something now to fix it. ;)

Thanks guys, and thanks for the video links. I think it would be easier if I had a Spanish notch/sharpening choil, but I don't really want one on this knife. Still, it gave me some direction. :)
Click to expand...

ok ya I see it now. I didn't see the plunge on the other side at first. My plunges come out semi straight. but they are really at a sharp angle. lol I have a lot to learn I'm afraid.. Do you have lights set up on either side of the grinder?
 
@Strigamort,

I have a low cost homemade file guide, 2 - 2 1/2" tungsten carbide scraper blades.

OT
 
zealot said:
ok ya I see it now. I didn't see the plunge on the other side at first. My plunges come out semi straight. but they are really at a sharp angle. lol I have a lot to learn I'm afraid.. Do you have lights set up on either side of the grinder?
Click to expand...

I have the grinder set up just inside the garage door. I've just been rolling it up and using daylight, mostly in the morning.

Old Traf said:
@Strigamort,

I have a low cost homemade file guide, 2 - 2 1/2" tungsten carbide scraper blades.

OT
Click to expand...

Sounds cool. Do you have any pictures of it? Maybe I can try to make something similar.

I went ahead and glued pieces of steel to the bolster area to act as a guide for the grinder. It actually works pretty well to keep the belt in place. I'm not sure if it's deflection or what but the belt only bites into the bottom near the edge. If I try to stand the blade up straighter the belt starts to cut into the spine. This happens even on the platen. :confused:

Next day off I'm gonna grab some files and a card.
 
Here's a pic of one I'm roughing out right now for a mini bowie

q3y1fPv.jpg


I haven't had any trouble with the belt digging in anywhere, in fact most of the time there are just light scuff marks on the steel block, but not really much material removed.
 
Yeah that's pretty much exactly how I've done mine. I'm using (as quenched) 1095. It's pretty good for this.

I'm not having any trouble with the belt biting the "bolster", just grinding too low near the edge. If I try to grind higher it starts cutting into the spine. Can't seem to get it to cut at the center of the blade. A decent belt and grinder would make the difference, of that I'm certain.

In any case, I'm going to try again in a little while when I get home.

Sweet bowie btw. Is that flat or hollow ground?
 
Strigamort said:
Yeah that's pretty much exactly how I've done mine. I'm using (as quenched) 1095. It's pretty good for this.

I'm not having any trouble with the belt biting the "bolster", just grinding too low near the edge. If I try to grind higher it starts cutting into the spine. Can't seem to get it to cut at the center of the blade. A decent belt and grinder would make the difference, of that I'm certain.

In any case, I'm going to try again in a little while when I get home.

Sweet bowie btw. Is that flat or hollow ground?
Click to expand...

That sounds more like a problem with where you're applying pressure possibly, or it could be the platen bending (are you using the stock platen?)

It's hollow ground. It's the testbed for the knife I'm making for my fiancé. It's going to be a coffin frame handle in desert ironwood burl. Should be pretty nice. :D
 
Strigamort said:
Sounds cool. Do you have any pictures of it? Maybe I can try to make something similar.

@Strig,

When I get set up for pictures, will post some. My 6 sq ft work allows one task at a time. However, bought 2 extra 2 1/2" scraperblades, they are about 3/8" wide, 2.5" long, so is not suitable for extremely large knives. You can either clamp them together, chuck into a vise to keep it together, or drill and tap tghen screw together.

OT
Click to expand...
 
Ian,

Do you grind with a work rest or freehand?

I've been grinding freehand since I started but I've developed bad tendonitis in my elbow and am switching to using a work rest until I can finish my grinding Jig.
I forgot that you can't use a file guide on the work rest though :( The superglued steel looks like a great solution for tighter plunges without a true carbide guide.
 
find a cheap pair of parallel clamps that has a good gap between the screws that will allow the blade to pass through. make sure you square the bars up so your plunge lines stay even.


(i'm on a buddys pc or I would post a link to a picture of a clamp I made to keep my plunge line straight when I grind on the disk sander.)
 
Richard, that sounds like my Lansky clamp. Too bad it's aluminum.

In a hurry but wanted to show that the glued bolster seems to be working. It's really hard to remove a decent amount of steel with my crappy set-up, it's taking forever. I'm just happy to see some progress though.

IMAG1984_zpsa5jzmyoa.jpg


IMAG1986_zpsikyvo3d6.jpg


I can't get decent pics in my garage. The knife actually looks better in person.

Not sure that I like the design but it's mostly just practice. It's cool to learn as I go. I'll keep updating as it moves along.

Any critique of the design is welcome.

Edit- a better pic of the grind. It's far too convex and needs a lot of meat removed between the edge and spine. I've noticed that the edges of my belt are curling.

IMAG1988_zpse8vuyx2w.jpg


Ian, I am using the stock platen which is very thin steel. It's bolted down at the bottom which is fine for non-precise work, but sucks for this. I really believe that I could make far better knives with better equipment.
 
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Sounds like the belt is bunching up when you apply pressure .All belt grinders do to some extent , but your little grinder is especially prone to it .More belt tension is normally the cure but your grinder wont tension up too good inherently .(A 1" belt is only so strong.)
 
Yeah I tried tightening it up and running the platen fairly far forward but that's when the belt snapped with my face inches away. :eek:

Fortunately I had safety glasses on, but I bet that 60 zirc could have done a number on my skin had I not been lucky.

@ old traf- I'm struggling trying to visualize the tools you and Richard are describing. Maybe I can find a pic somewhere of the tool in use.
 
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