My place...

'Type in your company slogan here'

2009-09-22 19:42




  New Spindle





Link / News Box

Your Link

Your Link

Your Link

Your Link

Your Link

Your Link


Text Box

Use this box to type any specials, new updates or even gallery pics here.


CNC - BT30 Spindle - Making the housing

So, to the left is a rendering of the housing for the spindle. The total length is 190mm and the diameter is 90mm. The flange is 125mm in diamter and has 6 mounting holes for M6 screws. I really wanted to make the housing out of some good quallity steel but ended up making out of aluminium. In the future I may "upgrade" to a steel housing if need be.





Here we are - set up for the first operation on the housing. The stock is 160mm in diameter so there was a lot of material to remove. The lathe is newly restored Storebro and it was a joy to use it for this project.




I started by squaring off the end and then drill it with a spotdrill so that I could use the live center. Then I started to machine down the 160mm bar.





In this picture the outer diameter of the lower part has been turned down close to 90mm and the rest close to the 125mm that OD of flange is supposed to be. I then started to work my way up thru the drill sizes. That's quite a long drill....




 ...and that's quite a large drill.






After roughing out the ID with the drill I started turning the bore for the lower bearings. These bearings are 72mm in diameter and I wanted a light press fit.





Slowly bringing it to size, measuring with a three point micrometer between each pass.





And then a final pass on the OD to bring it to it's final dimension. Then comes the fun part - turning it around and getting it to run true so that the upper bearing bore could be machined 100% (or close to) true to the lower one.




I made a "plug" that was a close fit to the lower bearing bore and iserted it before clamping it in the chuck. It can be seen sticking out just a little between the jaws of the chuck. This was obviously done so that the force from the chuck shouldn't destroy the nice bearing bore. A dial test indicator and a plastic hammer is used to make sure that the housing runs true - I managed to get with in 0.01mm.


First I machined the upper bore. When that was finished I made another "plug" since none of the live centers I had access to was big enough to fit the newly machined bore. Then I started to machine down the rest of the housing to its final dimension. When that was done I had one simple operation left and that when it happened. I wanted to take a light cut on the upper end but to able to do that I had to remove the "plug". And when taking that last cut the whole housing came loose from the chuck, resulting in some really uggly dents and one really scared operator (me).

A rotary table was then set up in the mill and mounting holes as well as the tapped holes for the flange was drilled and tapped. (Sorry, no photos of that op.)


These two last photos shows the finished housing. You can clearly see the marks from "crash" in the second photo. Hopefully it's just cosmetic and the housing is still straight with round bores for the bearings but only time will tell. If it IS messed up I will make a new one.




Copyright 2009 Henrik Olsson. All Rights Reserved.
Template downloaded from:
FrontPage Templates