Beginner tool bit grinding Fixture

[mmcmdl]

The one you want is the thread tool fixture . Grinds for 60 degree and Acme threads .

 

[WobblyHand]

I'm hardly a pro- but my HS shop teacher insisted on us learning it back in '72
No fixture, just you and the grinder in a love embrace
lol

At least you had access to decent grinders. All the grinders I had used tin foil for rests and shook because the wheels were imbalanced. So it wasn't easy to develop grinding experience. And no, I didn't know that the whole grinder wasn't supposed to walk away from me while using!

 

[cooper1203]

maybe im being dense here but i dont understand what the advantage is. You still have to free hand the angles

 

[markba633csi]

I was wondering about that too

 

[mmcmdl]

You still have to free hand the angles

This is used on a surface grinder for angles and relief . I sold one on here because it was useless to me .

https://www.hobby-machinist.com/threads/surface-grinder-fixtures.110667/

 

[cooper1203]

in the video Mr pete was using it on an ordinary bench grinder. i get it allows you to set the relief angles on the sides but the 80 degrees in the example in the video he free handed. is doing the relief angles the hard bit?

 

[mmcmdl]

Not sure as I don't view shop films . I found a pic of the threading tool fixture . Can't say if I still have it or not .

Post in thread 'Fun At Home Shop Projects ........commenly Known As " G " Or Government Jobs'

Feb 8, 2016

Very handy thread tool fixture . Has angles for 60 degree + Acme threads . For use on a surface grinder . This a solid holder but if you think you may have trouble with the square , either split the part and bolt together or just use a hole and reposition your set screw location .

Mill the crap out of it using whatever means you may have . Accuracy is up to you , sinebar or such . These are compound angles which give you your needed clearances on your finished tools . You may find it difficult calculating these angles , but it's half the fun . There will not be a square angle when you're...

• mmcmdl

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[GeneT45]

in the video Mr pete was using it on an ordinary bench grinder. i get it allows you to set the relief angles on the sides but the 80 degrees in the example in the video he free handed. is doing the relief angles the hard bit?

Not at all. It *is* the hard to describe bit. Easier shown than written about.

The home-shop guy (or gal) has an advantage in that (aside from threading tools) most angles don't matter much - a ballpark approximation will do. Relief and clearance angles become critical when you're trying to maximize the life of the cutter, but most of us aren't using HSS for substantial turning all day, every day. I use ~10* for all my "generic" cutters, because they're not dedicated to a particular material or task and that angle is pretty good for most materials.

A good grinder is a must, as is a good way to dress your wheels. If you've got some old crap (take my 80's Crapsman for example) relegate it to wire brush duty and get something that will spin reasonably true, then mount it in a stationary position.

GsT

 

[ltlvt]

I'm hardly a pro- but my HS shop teacher insisted on us learning it back in '72
No fixture, just you and the grinder in a love embrace
lol

I wish I had of had a high school shop teacher. Closest we came to was Ag. Learned a lot about how to cut the nuts off of hogs and calves but everything else was School of Hard Knocks. I post this type of videos in the Beginners thread for a reason. Just this simple JIG is an excellent training project for the new or old as dirt beginner. It is a thing of the past now that insert tooling is so cheap but the knowledge, they get from making it is what I am shooting for.

 

[cooper1203]

@ itlvt please dont think i am knocking you for posting the video or mr pete as a complete beginner i just dont understand how to use the item