After some wreckless thought & no real planning, the decision was made to build my own case, after seeing what I had laying around, then ording some material, I only had to wait a few days to get started.
My material showed up last week, so Thursday after work I got busy cutting aluminum,
Lots of preheating & welding to tie the .750" thick top, bottom & sides to the .5" front plate, I didn't get any pics since I was busy heating & welding,
After a little clean up it was time for machine work,
First the hole pattern was drilled to bolt back cover on.
Then flipped the box, lid down & started the bore for the input bearing with a hole saw.
The hole saw was run through both sides so the bores would be in line, finish work was done with a boring head in the mill,
Once complete I moved on to the intermediate shaft bore, with the smaller hole I could only bore one side of the box.
On the rear output the housing fits a 6.125 bore, but the register is only .150" deep, rather than bore a 6 inch+ hole & loose support for the intermediate shaft, I cut a 4" hole & stepped the register out, leaving more strength in the box.
The front output was bored through the other side, again to keep everything in line, clearance between the rear output housing & intermediate shaft/nut is pretty close, rather than grind for clearance I figured I'd use it for more support,
So after putting the housing in place, then drilling/tapping the mounting bolts, I dialed back in on the inter. shaft bore & fly cut a 2" pocket, a 2" OD washer will be used behind the inter. retaining nut, & should offer a little more support.
Here is the input/rear output after getting all the holes drilled/tapped for bearing/seal retainers.
Next up the whole unit was flipped over, I had to remover the cover, dial in on the inter. shaft bore, then reinstall the cover & bore the final hole,
More drilling & tapping for bearing retainers.
Test fit of the gears/shaft looked like it was going to work well.
The input gear is from a marrage box 205 & required a sleeve so I could use an output bearing to support the end of the input that would normally be in the pocket bearing,
Here is the sleeve installed,
When all the bores were done & bearing could be installed, i put everything in the case, first to make sure they would fit, but also to set up the the alignment of the gears, to get everything right, I had to pull the input shaft/bearing out of the case about .250" this was done with a spacer/washer I built, (but no pic) This put the input in line with the inter. shaft,
For the output I had to do a little work to the output shaft housing, first was taking .100" off the face that the bearing retainer/seal housing bolts to, then an aditional .050" off the face that bolts to the case, This lined the output gear up correctly with the inter. shaft, & also set the clearance between the two halfs of the output shaft.
With everything fitting in the case properly it was time to move on to the shift mechanism,
As mentioned before I'm using the stock 205 shift collar & fork, however a new shift rail would have to be built,
But first the case had to be bored for the rail,
To locate the shift rail bore I used the rear output housing, From the factory the rear housing has an ear that covers the shift rail bore,
I simply transfer punched through a stock 205 housing into that ear, then bored a .750" hole in the rear output housing,
With the housing bolted to the new case the hole could be bored in the correct location.
The shift rail will be sealed exit the case through the hole in the rear output housing, on the other side of the case I had to build something to support the shift shaft through its range of motion, & seal the hole in the case,
Basically I just set the cover on the mill, dialed into the shift rail bore, then drilled & tapped the bore to 1" fine thread, then build a boss that threaded into the bore,
Ok, I built the boss first, but who's paying attention anyway.
Either way the boss was threadad into the cover with a liberal amount of red locktite.
Once installed the boss was finish bored, then a hole had to be drilled & tapped in the case for the detent arrangement, while set up for that I decided to add a little bling, (edit) in this pic you can also see the 1/4" spacer behind the input bearing retainer.
The detent is a simple 1/2" bolt, cut to a measured lenth, then drilled/tapped for a 3/8 fine thread in the center, the spring & ball from a 205 is used along with a set screw & jam nut to set tension on the detent spring.
Here is the test bolt, (I replaced this yesterday with a stainless bolt, drilled/tapped the same way.
I was dissapointed to learn that the .750 end mill, cut my shift rail bores .005 over sized, & the material I had set aside for the project was .010 under,
so a fair amount of time was spent building a shift rail out of 1" stainless stock, getting it to size was easy enough, the challeng was getting a finish I felt would work with the seal. Then the shift fork had to be machined to work with the new shaft, kind of a snow ball effect, but I feel the finished part was worth the effort.
After some careful measuring the shaft was set up in the mill for detents, roll pin holes, & got provisions for linkage attachments.
In this pic you can also see an extra hole near the end of the shaft, this is a oil hole that feeds a galley drilled in from the end of the shaft, it does not so much lubricate the boss that is threaded into the cover, (since it's submerged in oil) but lets the oil out of the boss as the shift rail slides in,
Final assembly with the shift fork installed,
Here is the shift rail in place, the extra roll pin is to keep the rail/fork from going to far (out of gear) you can also see how the detent bolt/assembly works.
For sealing the shift rail the case was bored for a lip seal, the seal is behind the ear on the rear output housing, I did not get a good pic, but it can be seen behind the shift rail assembly in this pic.
With all the machine work done, the whole case got a good scrubbing, then began final assembly, as you can see in the pic above the shift rail seal was installed, then all the bearings in the rear output housing, finally the input bearing/retainer, & output housing were installed.
Next the rear output was dropped in.
Shift rail, fork, & collar were next.
Front output set in place,
The intermediate gear slids in next.
Finally the input shaft,
Earlier I posted about using a washer with a 2" OD that would rest against the saddle machined into the rear output housing, this is what that looks like after assembly,
After everything was assembled I slid a couple 205 yokes on the outputs to see what the scales had to say.
The assembled unit minus yoke/flanges,