Models for grinding HSS Lathe Tools

[mikey]

While I'll be the first one to support the philosophy of beginners learning how to grind their own lathe tools and sharpen drill bits. For those of us who were formally trained at a young age it now comes naturally to us, we sometimes wonder how beginners find it so difficult, particularly when they are a little bit older and just getting into the hobby of machining.

Do you think it might have something to do with being shown how to do it by an instructor who then critiqued your attempts and helped you to learn grind a tool?

Our guys are doing it alone, without an instructor. Given what I've seen in this thread, I think these guys are doing really well.

 

[9t8z28]

I just ordered it. Is it like a hard wax or soft wax? I have something called Nix Stikx that I use on my band saw blade. Its somewhat soft.

Wax lubricant. https://www.amazon.com/gp/product/B00QL52T7U/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

It seems to help when I've tried it with and without. I turn on the belt, then just touch the wax to it. It shouldn't take much.

 

[ttabbal]

I just ordered it. Is it like a hard wax or soft wax? I have something called Nix Stikx that I use on my band saw blade. Its somewhat soft.

It's quite soft. The tube is like a caulk or grease tube, I just hand push it from the bottom to get a little sticking out, then lightly touch it on the belt. Seems to last for the whole grind. I suspect the stuff you have is quite similar.

I don't find I need it on the lighter grit belts, I only use it on the 36 for bulk material removal. After that, I tend to use a light touch just to clean things up and prep for honing. It might be more useful for knife making or similar on the other belts as you might need to use them longer.

 

[mickri]

I have absolutely no room in my garage shop for a separate stand alone belt grinder. So I have been looking at my bench grinder for ways to make it better/easier for grinding tool bits. There is a medium grit grinding wheel on the right side and a wire wheel on the left. I think that a wire wheel is the most dangerous tool in my shop. One slip and it will tear your fingers apart. I have been wanting to replace the wire wheel for some time with a fine grit grinding wheel. Recently I have been thinking about mounting a disc sanding wheel instead of another grinding wheel on the left side of my bench grinder. I have not seen this done before. I could mount my drill sharpening guide to work off of the disc sander and make a table that could be set for different angles to grind tool bits. Would the disc wheel need to be balanced? What else should I take into consideration?

I have also done a drawing of a 6 inch grinding wheel and measured the angles that would be cut depending on the angle of a 3" wide table. This is what I found. With the table flat and on the center line of the wheel pushing a tool bit straight into the wheel flat on the table gives an angle of 3.7 degrees. If I angle the table up by 2.5 degrees the of the cut is 8.6 degrees. 5 degree tilt equals 13.6 degrees. 7.5 degree tilt equals 18.8 degrees. Because of the curvature of the wheel the angle cut is slightly greater at the top edge and slightly less at the bottom edge.

The current table on my bench grinder is very short and has no tilt feature. I would have to make a tilting table. Probably not hard to do.

I am looking for suggestions.

 

[mikey]

Instead of a sanding disc, I would mount a 6" CBN wheel if you want to stay with a bench grinder. CBN is made specifically to grind HSS and it will last for a very long time and stay flat. Sanding discs don't last very long at all grinding HSS and it takes much longer to grind it. A CBN wheel will also allow you to grind your drills.

The other option is to buy a small 2 X 42 belt sander and ditch the bench grinder. The footprint of such a device is as small or smaller than your bench grinder and can be configured to work quite well for tool grinding and most general shop tasks. We had a discussion about such grinders here: https://www.hobby-machinist.com/threads/help-me-decide-on-a-1-x-42-belt-grinder.70410/

 

[Downunder Bob]

Do you think it might have something to do with being shown how to do it by an instructor who then critiqued your attempts and helped you to learn grind a tool?

Our guys are doing it alone, without an instructor. Given what I've seen in this thread, I think these guys are doing really well.

Sorry Mikey, I wasn't trying to be critical of the learners attempts, yes they are doing very well. I was trying to comment on how those of us who have been doing it for along time, sometimes forget how we struggled in the beginning. Yes it was much easier having an instructor standing by your shoulder, and then put the tool in a machine and see how well it worked, or didn't.

 

[mikey]

Sorry Mikey, I wasn't trying to be critical of the learners attempts, yes they are doing very well. I was trying to comment on how those of us who have been doing it for along time, sometimes forget how we struggled in the beginning. Yes it was much easier having an instructor standing by your shoulder, and then put the tool in a machine and see how well it worked, or didn't.

Thanks, Bob, I misunderstood - my apologies. I've been doing this so long that I could grind a good tool in my sleep but it wasn't that way in the beginning. I would have paid to have someone teach me back then because I remember how horrible I was. To see these guys just jump in and grind a tool is amazing to me.

 

[Z2V]

We would not have done so well without this thread, that’s for sure.

 

[thomas s]

Yes this has been one of the best threads on this forum.

 

[mickri]

Just got back from a weekend checking on my boat and have another project that I have to get done. So it is at the top of my list.

That project is to cut 1/4 x 28 left hand threads in 316 stainless steel. The thread only has to be about 1/2" long. Does the tool to cut a left hand thread need to be the reverse of of Mikeys' thread cutting tool? What about the angle on the compound? Does that need to be reversed also? Never cut left hand threads before. Pretty clueless on this.