I did a bit of cardboard template making today, to decide how to make the mounting brackets for the transmission.
I have a couple of lengths of 50 x 6mm flat bar that has been waiting to be added to my trailer for so long that I doubt it will ever happen. I might as well just use it for this job.
No measurements were taken. I just placed cardboard over the end of the bellhousing and tapped with a hammer to get the outline and hole locations around the bell housing, and what I think might be the second mounting point on the top of the transmission.
Starting with the bellhousing bracket, once I had a layout of the holes and dowels I was able to figure out a way to catch them all with two strips of the flat bar.
I transferred the template marks by eye to the steel and cut it out and drilled holes. I then TIG welded at the apex of the inverted V and tested it for fit and accuracy. All being well I welded in a scrap off cut triangle (I keep a lot of triangular off cuts!) to strengthen the shape. Surprisingly it fitted fine once the dowel holes were reamed out a touch.
There is a bit of a gap where the bracket meets the cross-member, but that will be fine as I will cut it back another 2 or 3 mm to allow for the cross-member to settle in the rubber mounts.
I will also add some triangular fillets to each side to stiffen the bracket to the cross-member.
The bracket will be bolted to the bellhousing, at the top with two M10 x 1.5 x 50 hex nuts and bolts through the bell housing, and at the bottom by two M10 x 1.25 x 30 hex screws into threaded blind holes. I have the M10 x 1.25 screws and tap to clean the threads, on order.
As I didn’t have time to weld the bracket to the cross-member this evening, I decided to just spray it with grey primer for now and deal with it another day.
And, yes, I need to add more filler rod to that weld when I add the triangular fillets.