Tool and cutter grinder build

[outsider347]

Mark
wondering what software you use to create your drawings?
tks
ed

 

[NEL957]

Mark
Here is a AIR BEARING TECHNOLOGY, it might answer some of the questions.
http://www.westwind-airbearings.com/airBearing/documents/AirBearingTechnologybriefv2.pdf

There is a thread in another group and maybe some of the members are in this group.
Here is where you can find the topic:
http://www.practicalmachinist.com/vb/general/making-precision-spindle-air-bearing-202159/

Myself, I thing it is not needed because the grinders have all the other parts that most build of the air spindle build it for. If the machining is honed and polished there is no need for air and another thing that is the enemy of air spindles is moisture. If any moisture gets in the air and it is not cleaned right away rust will set in now. I do not know but I think I will finish the build, then look for needed improvements.

But that is my opinion
Nelson Collar

 

[Mark_f]

Mark
wondering what software you use to create your drawings?
tks
ed

Actually , I do it the hard way. I have tried some of the cad and other software out there but it is a PITA, and I can't figure it out. I draw my prints with a paper, pencil, and ruler.

The grinder prints are a little different. They are already drawn and printed, so I open them in my photo editor program ( it is called GIMP) and I re-scale the size, erase everything I don't want, add my new text and figures. Then I open it in windows paint and use the drawing features to redraw everything I want and it ain't easy. I have to draw a circle and then erase the part I don't need to make a curve line. It takes me hours to edit these drawings. hell, it takes me hours to draw a print by hand too. I may have to switch between programs a dozen times and I have to save it every time I switch. so you see, I do it the hard way :rofl: :rofl:.

 

[Mark_f]

Mark
Here is a AIR BEARING TECHNOLOGY, it might answer some of the questions.
http://www.westwind-airbearings.com/airBearing/documents/AirBearingTechnologybriefv2.pdf

There is a thread in another group and maybe some of the members are in this group.
Here is where you can find the topic:
http://www.practicalmachinist.com/vb/general/making-precision-spindle-air-bearing-202159/

Myself, I thing it is not needed because the grinders have all the other parts that most build of the air spindle build it for. If the machining is honed and polished there is no need for air and another thing that is the enemy of air spindles is moisture. If any moisture gets in the air and it is not cleaned right away rust will set in now. I do not know but I think I will finish the build, then look for needed improvements.

But that is my opinion
Nelson Collar

Well, I spent hours last night on the internet researching the air bearing. I know that part is a ways off but you never can start research too early. The more I learn about air bearings , the more I am thinking I ain't gonna have one. They are super fussy to make if not close to impossible. I do know they are too expensive to buy. used ones are $400 to $600 dollars on ebay. I have used an air bearing many moons ago when land was young and the buffalo still roamed. They are nice, but I am inclined to think Like Nelson say. With a good hone job and fit it will work without the air satisfactorily. So, the air bearing is still up in the air.


Edit: I just read this post. No pun intended :rofl:

 

[wrmiller]

Well Mark, here I thought I was the only one out there still using Gimp, only to find out other Old Guys are still using it too. And I thought I was unique. :lmao:

As for the air bearing: I figured you'd eventually decide you don't need that level of pain. I have used them in the past on projects that are being paid for by other people (DARPA) but figure it might be a tad overkill for this. Would have been entertaining to watch though. )

 

[Mark_f]

Busy day in the shop today. I feel great because I am almost finished wit the lower half of the work head. It is great because I think this maybe the most difficult part of the build.

I started by machining the spindle for the rotary table. I cut the 1/2" post , then put it in a collet to finish. I machined the 90 degree seat and finish milled the top of the spindle. The reason for putting in a collet to finish was, it is important that the seat, the reamed center hole, and the spindle shaft are all concentric to keep accuracy. the table needs to rotate exactly on center.
This is the finished spindle. If you look close you will see my major screw up. there is a .187 spacer on the large end of the spindle. this is because I misread the prints and miscalculated the depth and cut the underside of the table too deep by a quarter inch. This would require the need to remake the spindle if my repair was not successful, but it seems "revision 1" may work.

To make the 3 inch rotary table, I chucked up a chunk of 3" diameter mystery steel ( I think it is CRS). After turning .010" off the outside to clean up, I started what I knew was going to be the hardest part of this build. cutting the T slot in the table. The prints show making it in two pieces and Loc-tite them together. I have no doubts that this would work and would recommend the two piece method for anyone not well experienced. I started by making the .312 slot .250" deep using a parting tool. It took four plunges to get the slot cut and halfway cleaned up. Now you will notice the crappy looking ugly tool in the holder. it is for cutting the "T" in t-slot. I quickly ground this on a new piece of 5/6" HHS. If I owned a tool grinder, I could have made a nice one :rofl:. There is another one on the other end that is the reverse for cutting the other side. I thought I could cheat and just grind one, then turn it upside down and reverse the lathe. DO NOT TRY THAT! It went bad and was really ugly, so I ground the second end. Turning the T slots was very difficult and took a long time, but I am glad I made the table in one piece.

This is another view of the ugly tool.

With the T slots cut ,it is time to bore the center hole for the table spindle. This hole was bored to a snug slip fit for the spindle.

After boring the center hole , I started machining out the underside of the table.

This is the finished table. THIS IS WHERE I SCREWED UP! I misread and miscalculated the depth of undercut on the rotary table and machined the underside .250" too deep. There is NO WAY I am making this table over again so it is time for "revision 1". I could remake the spindle and compensate for this mess, OR make a spacer. I opted for the spacer because once it is loc-tited in there, it will stay. I will also make a brass insert for the recess left in the center of the top because the spacer dropped the spindle .187". That will be "revision 2" and all is good again :rofl: ( see , there are no mistakes, only revisions :nuts.


This is the top of the table. It will get finished machined after the spindle is loc-tited and the brass insert is put in.

The spindle is permanently affixed into the table with loc-tite so the spacer worked.

I almost forgot this detail. a notch is machined in the table so T nuts can be inserted.
One last detail today. I made the lock bolt for the tilting block so I could assemble everything to check the fit.

This is the lower half of the work head, temporarily assembled to see how it looks ( and to make me feel good). I painted the front and rear plates with the black wrinkle finish. I am happy with the look.

 

[Mark_f]

Well Mark, here I thought I was the only one out there still using Gimp, only to find out other Old Guys are still using it too. And I thought I was unique. :lmao:

As for the air bearing: I figured you'd eventually decide you don't need that level of pain. I have used them in the past on projects that are being paid for by other people (DARPA) but figure it might be a tad overkill for this. Would have been entertaining to watch though. )

So ....... you were going to let me flounder Trying to make one and watch?


that would not be nice :nono:

:rofl: even if it was entertaining :rofl:

 

[wrmiller]

Nope, figured you would come up with a way to make one.

 

[Mark_f]

Nope, figured you would come up with a way to make one.

Actually, I have and may experiment a little with it. Got to get my hands on a piece of nice really close ground shaft about 10" to 12" long and at least 1" diameter first. Hey, I got nothing to lose. This kind of machining is at the top of the game and considered beyond the machinist's capabilities. It is usually done on CNC equipment and grinders.....none of which I have.

But I been told I couldn't do something before....:rubbinghands:

 

[Ulma Doctor]

truly inspirational Mark!
excellent work!!!
:man: