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I angle my internal grinding wheels a little .
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Building A Tool Post Grinder
- Thread starter Mark_f
- Start date
Do you dress a narrow surface on the corner then before grinding?
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- Jul 26, 2011
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Yes. I don't know if it is correct practice,but it works. Maybe you are just supposed to use a narrow wheel. That seems more workman like. But,you have to work with what you may have at home at the moment.
I know I break "machining" rules every day!!
But,I always got the job done. And,there were PLENTY of oddball jobs given by the museum. Like machine a PROPERLY CONVEX CURVED Greek column 1' tall,with PROPERLY CURVED flutes in it! Greek columns were not just straight tapered. They also were a bit convex on their shapes.
I also had to get the flutes curved,so that the flat lines between them would properly taper towards the narrowed tops of the columns. (Hope this makes sense!) No pics. taken.
This was for a pair of candle sticks copied from an 18th. C. original pair. Considered important because they were the only 18th. C. candle sticks made with properly proportioned slightly convex curves along their length. A present for the retiring president of the museum. Then,offered as a product for $25,000.00 back in the 80's. I don't know how many they sold,but I'm sure they sold some to the wealthy donors of the museum.
I know I break "machining" rules every day!!
But,I always got the job done. And,there were PLENTY of oddball jobs given by the museum. Like machine a PROPERLY CONVEX CURVED Greek column 1' tall,with PROPERLY CURVED flutes in it! Greek columns were not just straight tapered. They also were a bit convex on their shapes.I also had to get the flutes curved,so that the flat lines between them would properly taper towards the narrowed tops of the columns. (Hope this makes sense!) No pics. taken.
This was for a pair of candle sticks copied from an 18th. C. original pair. Considered important because they were the only 18th. C. candle sticks made with properly proportioned slightly convex curves along their length. A present for the retiring president of the museum. Then,offered as a product for $25,000.00 back in the 80's. I don't know how many they sold,but I'm sure they sold some to the wealthy donors of the museum.
Last edited:
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Having done a lot of ID and Jig Grinding in the past. I believe many people angle their tool post grinder because it puts less of a stress on the grinder to eliminate any possible belt slippage for those using a belt. By angling the the tool post grinder you will be using less of the wheel and thus causing any wear down to happen at quicker rate. This may not be a problem when doing a single part but can be a bother if doing multiples. By going straight in the end will wear down first. leaving the rest of the wheel to do less work and finish the hole.
Or at least that is what I was taught.
Or at least that is what I was taught.
All the literature I have found on the Internet ( it must be true if it's on the Internet .... Right?
) says to angle the wheel slightly and dress a narrow edge flat, then grind with this dressed edge.
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That is correct. It HAS to be,because that is what I do!! Actually,I do it because it makes good sense.
Actually,I do it because it makes good sense.Today , since I am waiting on materials for the precision drill sharpener, I got back on my tool post grinder. I needed arbors for wheels. Since I want small ID wheels, like 3/4" or a little smaller, the only ones I could find are at McMaster Carr are mounted on a .250" shaft about 1 1/2" long. So...... I need a small arbor with a small chuck on the end and can not find one ..... So we make one .
This is the completed arbor with a chuck on the end. It is made entirely from drill rod , so I can harden it if I choose or need to. Note the wrench flats on the end of the shaft. They fit a 7/16" wrench.
The shaft is 8" long of 1/2" drill rod ( to fit the 1/2" ER20 collet). The end was reamed .250" for 1 1/2" deep. Then threaded 7/16-20. The end was turned down to 25/64" and beveled 30 degrees on the end.
I used my Dremel with a thin cut off wheel to cut three slots , 120 degrees apart. The nut was made from .750 drill rod. Drilled with a custom ground drill bit. The bit was ground with a 30 degree angle to match the end of the chuck , then tapped 3/4 of the depth with a 7/16-20 tap.
I put the assembly on my mill using my hex collet block to put a hex on the nut to fit a 5/8" wrench.
The arbor fits my grinder spindle perfectly. I can extend or shorten it as needed.
I also need an arbor to hold my 3" diameter external grinding wheels. I used a piece of .750 drill rod for sturdiness . Turned one end to .5000 " to fit the grinder spindle. I left a 1.50" center section.
The other end was turned to .5000" diameter to fit the grinding wheel. I then threaded the shaft 1/2-20 leaving a .500" long shoulder for the wheel to register on. The washers are a pair of good quality heavy 1/2" washers that happen to be a close fit on the shaft. I stoned both sides of each washer flat then mounted on the arbor with a spacer and turned the OD true. The nut was a good fitting grade 5 nut and machined thinner to be less bulky.
I ran the grinder today and it does not get as hot on the spindle where the seals rub, they must be wearing in. The spindle runs true and smooth. The machine is a little noisy , but I think it is the motor and mostly the belt. The belt may be too heavy. I probably should have used to smaller belts in parallel . I am about ready to do a test grind. If it should show the vibration, the first thing will be to make new pulleys and try a light flat belt.
Stay tuned .......
.This is the completed arbor with a chuck on the end. It is made entirely from drill rod , so I can harden it if I choose or need to. Note the wrench flats on the end of the shaft. They fit a 7/16" wrench.The shaft is 8" long of 1/2" drill rod ( to fit the 1/2" ER20 collet). The end was reamed .250" for 1 1/2" deep. Then threaded 7/16-20. The end was turned down to 25/64" and beveled 30 degrees on the end. I used my Dremel with a thin cut off wheel to cut three slots , 120 degrees apart. The nut was made from .750 drill rod. Drilled with a custom ground drill bit. The bit was ground with a 30 degree angle to match the end of the chuck , then tapped 3/4 of the depth with a 7/16-20 tap.I put the assembly on my mill using my hex collet block to put a hex on the nut to fit a 5/8" wrench.
The arbor fits my grinder spindle perfectly. I can extend or shorten it as needed. I also need an arbor to hold my 3" diameter external grinding wheels. I used a piece of .750 drill rod for sturdiness . Turned one end to .5000 " to fit the grinder spindle. I left a 1.50" center section. The other end was turned to .5000" diameter to fit the grinding wheel. I then threaded the shaft 1/2-20 leaving a .500" long shoulder for the wheel to register on. The washers are a pair of good quality heavy 1/2" washers that happen to be a close fit on the shaft. I stoned both sides of each washer flat then mounted on the arbor with a spacer and turned the OD true. The nut was a good fitting grade 5 nut and machined thinner to be less bulky.I ran the grinder today and it does not get as hot on the spindle where the seals rub, they must be wearing in. The spindle runs true and smooth. The machine is a little noisy , but I think it is the motor and mostly the belt. The belt may be too heavy. I probably should have used to smaller belts in parallel . I am about ready to do a test grind. If it should show the vibration, the first thing will be to make new pulleys and try a light flat belt.
Stay tuned .......
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I hope the tapered shaft has a draw bar! You don't want that flying out at high speed!
When I make those,I save a little metal to grind out while the arbor(s) are running at full speed. It is hard to get them to run really true after they are running at high RPM. Variations in the density of the metal is enough to throw them out of true when they are run very fast. The tiniest variation is greatly magnified by centrifugal force.
On post #77,what is a "deemed"?
When I make those,I save a little metal to grind out while the arbor(s) are running at full speed. It is hard to get them to run really true after they are running at high RPM. Variations in the density of the metal is enough to throw them out of true when they are run very fast. The tiniest variation is greatly magnified by centrifugal force.
On post #77,what is a "deemed"?
There is no tapered shaft..... The collets hold tight.
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I'm pretty sure that was "auto corrected" from "Dremel"...
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