Jeff 98XJ WI said:
Damn Brad, you're making me sick with all those fancy machines! Why the hell did you even screw with that D30 front when you had the ability to MAKE new tubes for a 44? Unbelievable. How did you press the tubes into the housing? Did you use a long threaded rod of some sort and just pull the tubes in with the threads? I don't think that's what you did, but it kind of looks like it in the pictures. Give me some explanations. Did you turn the ends of the tube a touch for a press fit in the housing? Very interesting how you bored out the old tube pieces from the housing. Were they 1/4" wall? How did you open up the plug weld holes after the tube bores were opened up? Just smack the old weld with a chisel? Did the plug weld area present a problem to the boring cutter since the plug welds are quite hard? Again, I'm impressed. Jeff
I once asked about retubing and the first response started with, "drill out the plug welds and..."
Whooooa. That ain't gonna happen. Tried starting with a 1/16" drill bit and couldn't make a dent.
Those welds are HARD.
Ended up with a .025" taper in the housing when fly-cutting the tubes out from the tool hitting them. That's with a carbide tool.
I was able to just knock the rest of the weld out when it got thin enough and then recut to get rid of the taper. Machined it to a .012" press fit.
To keep everything straight I took a piece of 1.75" X 45" solid chrome OD bar and threaded a 1"-7 ID thread in both ends.
I then made steel bushings with that ID to fit in the housing bearing journels.
I machined the tubes to length and OD fit and then made bronze bushings for the outer ID end to fit the 1.75" rod. That gave me bearing surfaces in the housing and both tube ends to keep everything lined up for welding.
After preheating the hell out of the housing ends, I slid the tubes on the chrome rod and used a 1"-7thrd bolt on one end and a piece of 1"-7thrd threaded rod and nut on the other to press everything together.
I left it all bolted together from there on through the welding and cooling processes and then used the same method to press and weld the inner Cs on.
I was kinda worried about finding the whole thing might have tweaked from the welding/heating/cooling processes (I'd find out when the time came to remove the 1.75" rod) but it slid right out when done.
