Deckel knock-off tool grinding

[Larry$]

Stefan shows how to do 4 facet drill grinds. Takes a few tries to get it into your head but works great. I made a viewing microscope to see progress.

I watched that video. But I have never done all those angles on a bit and none of my commercially made bits have them. Maybe it's ideal but is it worth the trouble? I use a commercial bit to set the angles when I get ambitious enough to use the tool grinder. Otherwise I just use the bench grinder.

 

[Larry$]

I did remove the 0 stops in the head to be able to do negative angles.

If you pull on the outer part of the stop it will disengage and allow you to move past the stop points. It is spring loaded. Loosening the little set screw will allow you to adjust the stop point using the hex, then retighten the set screw. I wish there were instructions for all the adjustments possible and when to use them and how to get everything set to exact zero. It can be figured out but some things aren't very obvious. I made a brass, knurled, threaded plug for the hole where you insert something to lock the spindle shaft. Trying to keep it clean. I need to make a better dust hood than just my shop vac hose end.

The edge on my diamond cup wheel has become rounded. I'd like to get it square. I was thinking of just putting a diamond point in a collet and traversing the x-axis across the edge of the wheel, Will that work? or what is the "correct" way?

 

[gerritv]

The benefit of four facet is significantly lower feed pressure. My experience with smaller drills (2-10mm) bears this out. At same time I usually convert them to 135degree.

Not all grinders of the Deckel S0 style have that spring loaded plunger to lower the 0 detent. Alexander e.g. had it only on their later versions, mine not being one of them. I will get ambitious one day and retrofit a similar mechanism.

Several good articles on drill geometry:
- http://www.neme-s.org/2005 May Meeting/drills.pdf
- https://www.newmantools.com/machines/drillpoint.html An article by Joseph Mazoff

 

[Larry$]

The benefit of four facet is significantly lower feed pressure. My experience with smaller drills (2-10mm) bears this out. At same time I usually convert them to 135degree.

Not all grinders of the Deckel S0 style have that spring loaded plunger to lower the 0 detent. Alexander e.g. had it only on their later versions, mine not being one of them. I will get ambitious one day and retrofit a similar mechanism.

Several good articles on drill geometry:
- http://www.neme-s.org/2005 May Meeting/drills.pdf
- https://www.newmantools.com/machines/drillpoint.html An article by Joseph Mazoff

I read the articles. And I agree that having a secondary relief or web thinning would make for easier penetration. On small bits I've usually ground greater relief angles than what they come with. 135* bits do seem to walk less. I never use large diameter bits w/o pilot drilling. The bits I use most often are a set of Cobalt screw machine bits. I found out how brittle they are when I dropped one. I've ground some bits with the 4 facets but for my hobby work I'm not sure it is worth the extra fooling around. Most often I just do a quick grind on the bench grinder. Been doing that for a long time before I got the tool grinder. We've got a Weinig profile grinder for profile blades. I can make a template for most any shape and grind two or 4 knives to nearly identical diameters while installed in the head. We always do a secondary grind. Same idea as your 4 facet grind. The catch is there has to be some clearance between the body of the head and the spindle, so not all knives will be doing the same amount of work. You have to assume you are just getting a single knife finish. There are molders that have profile stones to bring all knives to the same exact diameter. Each time that stone is lowered onto the spinning blades the result is more healing action, friction. You start to see burnishing. Those machine can feed at more than 12 feet a second. Second, not minute.

 

[NC Rick]

If you pull on the outer part of the stop it will disengage and allow you to move past the stop points. It is spring loaded. Loosening the little set screw will allow you to adjust the stop point using the hex, then retighten the set screw. I wish there were instructions for all the adjustments possible and when to use them and how to get everything set to exact zero. It can be figured out but some things aren't very obvious. I made a brass, knurled, threaded plug for the hole where you insert something to lock the spindle shaft. Trying to keep it clean. I need to make a better dust hood than just my shop vac hose end.

The edge on my diamond cup wheel has become rounded. I'd like to get it square. I was thinking of just putting a diamond point in a collet and traversing the x-axis across the edge of the wheel, Will that work? or what is the "correct" way?

I don't think you want to dress diamond with a diamond. It seems like the way I had heard to do it was at a lower speed with a silicon carbide abrasive which wears quickly. The Shars diamond wheels are not very expensive, I'd be tempted to get a new one and use the old one in all the ways I'm not supposed to
I have purchased extra hubs to make for quicker and more repeatable wheel changes.

 

[C-Bag]

I don't think you want to dress diamond with a diamond. It seems like the way I had heard to do it was at a lower speed with a silicon carbide abrasive which wears quickly. The Shars diamond wheels are not very expensive, I'd be tempted to get a new one and use the old one in all the ways I'm not supposed to
I have purchased extra hubs to make for quicker and more repeatable wheel changes.

Is yours a Shars unit too? I would like to find extra hubs too but the Shars ones are not the same size as my clone

 

[NC Rick]

Is yours a Shars unit too? I would like to find extra hubs too but the Shars ones are not the same size as my clone

my Machine is the genuine article, a real Shars It's been a while but I think the arbor o.d. is different than many others (20 vs 25mm??) but I thought the taper Mount was the same. I also think if you ask or look in the catalog, shars may have both styles. I wasn't prepared nor skilled enough to do the Stephan thing and make my own!

 

[Janderso]

It would be great to have one of those. I just can't justify the expense for a hobby guy.
It sure would be fun to be able to cut all those angles, sharpen everything. look at the money a guy could save.
How much is the full kit from Shars?? With all the attachments?

A cool grand $$$$$$$$$$

Universal End Mill Cutter Drill Bit Grinder Sharpener

www.shars.com

 

[NC Rick]

It would be great to have one of those. I just can't justify the expense for a hobby guy.
It sure would be fun to be able to cut all those angles, sharpen everything. look at the money a guy could save.
How much is the full kit from Shars?? With all the attachments?

A cool grand $$$$$$$$$$

Universal End Mill Cutter Drill Bit Grinder Sharpener

www.shars.com

If you put value on your time the buy in price is just the tip of the iceburg.
I bought mine because I'm frustrated by not having a surface grinder, want to make special tool geometry (most have been for the lathe) and to try to learn and become more skilled / less geometrically challenged. The monetary justification for me likely comes from the learning aspect. Now I get to make all those cheap Chinesium brazed carbide boring and turning tools actually cut like they are supposed to. I could have bought a lot of good quality tools and been ahead but if I get another 20-30 years of play time I'll recalculate.

 

[C-Bag]

my Machine is the genuine article, a real Shars It's been a while but I think the arbor o.d. is different than many others (20 vs 25mm??) but I thought the taper Mount was the same. I also think if you ask or look in the catalog, shars may have both styles. I wasn't prepared nor skilled enough to do the Stephan thing and make my own!

Thanks for that head up Rick. The Shars website seems to be getting better to navigate. But I swear that smaller hub was not on their site before. Now I just need to find the time to pull the hub on mine to confirm it’s the right one.

Has anybody pulled the hub before? I’ve heard some mention a puller but they seem to think everyone got one or made one. I would just like to swap between my stone and diamond wheels without having to rebalance.