First attempt at grinding, how bad did I do?

I got an 8" grinder. Got an 80x white wheel. Got the spiffy Veritas rest and holder.

First attempt was with my beater chisel that I use for scraping glue off the bench and various other nasty business. It actually has a decent bevel on it for the first time ever now.

Then I went for the pitted #6 blade.

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was going to show that picture and ask if it was okay if it turned that color as long as it didn't turn blue, but well once I saw it zoomed in I could see that it *was* blue in one spot near the top, which I couldn't see by eye before. So clearly that's bad.

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blade I still don't care too much about, but it's not garbage. It's mostly not changed color at all, except for that one spot near the top again. which this time I don't see any blue. So now I get to ask my question, is this okay?

The plane iron is thinner than the chisel so I assume it's harder for it to dissipate the heat. Because it's in the same spot on two attempts that got hotter it must be a technique thing. I was trying to just make a light pass straight across, and I went for the water after every pass. I guess not light enough.

-Leuf

Reply to
Leuf
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You most likely need to dress the wheel to remove glazed abrasive and open it up a bit. In addition you will get less heat if you radius the wheel to make a smaller contact with the steel. A 60grit wheel is more than sufficient, after all you will be honing the cutting edge after grinding. If you have not flattened the back of the chisel then your best efforts will be wasted.

Daily Grind Sharpening Service

Reply to
beecrofter

Probably.

I wouldn't lose any sleep over it, anyhow- as I use a regular grinder with stock wheels, I've burned a fairish number of chisels over the years, and had to grind past the bluing a little bit at a time, and it has always seemed to me that any loss of temper is confined to the specific area that changed color. Once the discolored area is ground away, everything seems to be just fine again.

Also, when I say I've burned chisels in the past, I mean it- what you've got shown is almost nothing. I wouldn't have even seen it if you hadn't pointed it out. If it turns dark blue, with some yellow and orange discoloration around it, that's the time to worry about it.

Reply to
Prometheus

Sounds like you have the right equipment. I love my Veritas rest and holder.

I've learned some things that you might already know, but I'll pass them on anyhow.

First, I shape the blade at a 90* bevel. If I'm trying to remove serious metal, the feather edge will burn every time. After it is shaped/square or what have you, then I set the bevel angle (and it's so easy with the Veritas) and sharpen the blunt edge I just made.

The second is to put a finger on the blade about 1" back from the wheel. (I keep alert, don't want to be known as Stumpy). When my finger gets hot, the blade is too, and it needs air or water cooling.

And third, if I am sharpening HSS tools (like lathe chisels),I don't dunk them in water. The rapid cooling makes for micro cracks which degrade the edge quickly.

It's wonderful to have sharp tools!

Old Guy

Reply to
Old guy

It is OK to dunk HSS, the key is to not get the metal so screaming hot before dunking. Think for a moment about the tools for a metal lathe.

For a wood chisel the grinder is a great tool for getting the blade close to sharp, then you get it sharp by hand with the stone.

Reply to
Roger Shoaf

I need more practice. I ended up not even close to square on the plane iron. Everything with the rest seems to be square, I even tried clamping up one of my squares in the holder and it made even contact across the stone, so I'm pretty sure the rest is setup right

There's a lot of play between the slot in the rest and the bar on the holder, necessary so you can pivot. Do you keep the bar pushed in, or let it rest on the back edge?

I've been putting off a sharpening session for too long. Pretty much everything in the shop that's supposed to be sharp aint. There's one chisel that's still borderline useableI have the original veritas honing guide, I'm probably going to suck it up and get the mk II. I have a $50 GC from christmas that has somehow managed to not be spent already.

-Leuf

Reply to
Leuf

I think that did the trick. How often should the wheel need to be dressed?

-Leuf

Reply to
Leuf

It varies quite a bit, but you can see the difference in the amount of material being removed vs hopw hot it gets as well as the wheel taking on a glazed shine. A dressing brick is just coarse silicon carbide, much like a rubbing stone for concrete. Don't breathe the dust! A good jig for chisels is a piece of pvc pipe rested against your foot ( or a batten on the floor) with the chisel inside. It's like having a 6' handle on the chisel and puts an ever so slight radius on the blade in the process. I use a similar setup with timber framing slicks. As for squareing things up, nothing beats a line scribed through a layer of magic marker ink as a guide. You also may find that a shorter bevel is more durable than the factory one. An 8" wheel gives a nice hollow grind and saves on honing time.

Daily Grind

Reply to
beecrofter

I had to learn to use the darn thing. I don't understand why there is so much slop between the base and the slider part. I prefer to let the bar ride on the bottom of the slot. Trying to keep it riding on the top of the slot doesn't work well for me.

What I do is to set the blade up just touching the wheel. Of course after the first pass it doesn't. So I just put a little downward pressure on the blade, the tool rest base flexes, and the blade touches the wheel again. I'm aware it changes the bevel angle a smitch, but I don't worry about it.

It seems to let me grind my tools gently.

As far as square, I've never been able to just put the tool in the slider piece and have it come out square. I need a visual reference to help me. I've found that it works best for me to color the back edge of the blade with a magic marker, then scratch a true square line in the color with an awl. With that visual reference, I can get the end as true as I want it. I don't grind all the way back to the mark.

Actually, I use the grinder to get the shape and the bevel on the tool, and then switch to sandpaper for the sharpening and honing. (Using the cheap one wheeled $15 honing guide.)

My main use for the tool rest is getting the right bevel on lathe chisels.

It's a pain when EVERYTHING is dull!

Old Guy

Reply to
Old guy

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