AlfaGTA
Diamond
- Joined
- Dec 13, 2002
- Location
- Benicia California USA
Bit slow here and folks seem a bit tense so though it might be nice to share a few shots of a job i am finishing up.
Some time back i posted photos of the parts of a job i was given to straighten the main housing bores on a Porsche 917K.
Crankcase is mag. and long enough (35") to be a size issue.
Lots of work has gone into this project. Some tooling construction and some false starts , and finally i am down to the short straws.
Engine is built with a lower shaft running in the case that delivers the output power from a spur gear at the center of the crank.
Last portion of the job was to over bore the housings that carry the shaft support bearings....
This was necessary to assure that the crank and output shafts were running dead parallel and at the correct center to center distance to give the proper gear lash.
Machine is setup to run horizontal. Alignment is done using the actual rotation of the crank and all adjustments to tram done via the universal table (that thing might be the best accessory ever)
Boring tooling is Sandvik "Capto" fine boring head coupled with a base adapter (CAT 40) a 100 mm spacer sleeve and two 80mm spacer sleeves. (needed to buy an additional 80 mm spacer for this)
Here is a shot of the boring bar fitted so you can see the relative length (20" from the tool face to "CAT" flange.
Fine boring head....uses insert tooling, in this case high positive. Adjustable in ..01mm increments on the diameter....
Setup is too long to to fully exit the case on retraction, so the technique is to set the bar into the case then make the connection between the machine and the bar.
I used the Capto joint at the spindle adapter being it was shorter and easier to control when making up the joint....
More fun to follow.
Some time back i posted photos of the parts of a job i was given to straighten the main housing bores on a Porsche 917K.
Crankcase is mag. and long enough (35") to be a size issue.
Lots of work has gone into this project. Some tooling construction and some false starts , and finally i am down to the short straws.
Engine is built with a lower shaft running in the case that delivers the output power from a spur gear at the center of the crank.
Last portion of the job was to over bore the housings that carry the shaft support bearings....
This was necessary to assure that the crank and output shafts were running dead parallel and at the correct center to center distance to give the proper gear lash.
Machine is setup to run horizontal. Alignment is done using the actual rotation of the crank and all adjustments to tram done via the universal table (that thing might be the best accessory ever)
Boring tooling is Sandvik "Capto" fine boring head coupled with a base adapter (CAT 40) a 100 mm spacer sleeve and two 80mm spacer sleeves. (needed to buy an additional 80 mm spacer for this)
Here is a shot of the boring bar fitted so you can see the relative length (20" from the tool face to "CAT" flange.
Fine boring head....uses insert tooling, in this case high positive. Adjustable in ..01mm increments on the diameter....
Setup is too long to to fully exit the case on retraction, so the technique is to set the bar into the case then make the connection between the machine and the bar.
I used the Capto joint at the spindle adapter being it was shorter and easier to control when making up the joint....
More fun to follow.