I finally got the courage up to make this crucial cut. I reef'd on the capture screw to compress the 3 pennies and went to town on the lathe.
Stats: 14.4mm diameter for the 14.5mm hole in the LB. Drilled through the screw using #19 drill bit. And counter-bored the screw for knocking off the sharp edges.
This drilling of the screw will allow more heat shrink tubing on the center post.
I have 4 Magic Flight boxes. They all fit a little different depending on vintage and workmanship. This fits tightly in all of them save 1. Therefore I don't believe making negative contact will be a problem. I am wondering about positive pressure. I may need to add a very small taper to this stack.
And for the post piece, turns out the hole in the bottom piece is not a rivet as I thought. It is in fact a solid gold-plated contact to the MOD where the inside has a 3mm 'receiver' for some kind of press. Note where the mark is left on the copper tube to know it is not bottoming out. I want a press-fit on the diameter, not the bottom of the contact.
Stats: 1/8" copper tube from any hobby store. Start with ~38mm. Size the seat [image] and shoot for 24.5mm from the mating face of the tank to the top of the copper post. Adjustments can be made with files or fingernail files. You want something near 'almost flush'.
The plastic insulator is only tacitly affixed. When I shrunk the shrink sleeve, this contact was easily removable. This makes no difference in this configuration as the post pushes on the contact anyway. I can almost replace it knowing this. But it is a good contact and it is gold plated so I tapered my 1/8" copper tube to about 1.2-1.5 degrees. The engagement happened at about 1.5mm. That is where the numbers start stacking up.
The white shrink tube is to keep the contact from just being loose.
And once screwed together...
Followed my be moment of truth...
Yep, 0.07 ohms on this brand new Launch Box from Magic Flight.
I chased the variation on depth and found my ancient LB to be the deepest. The shoulder of the tank fits flush with the box. On the other 3 boxes, I have about 1mm clearance/margin.
3 of the 4 launch boxes hold this modified tank nice and tight. My daily driver is an oddball. The hole is huge compared to the rest and the look fits loose. When I try to use my mod'd tank on the other boxes, it won't even fit in the hole. This walnut daily driver is the one I had so much trouble with holding the v1.0 MF power adapter.
Therefore,
@Choices, this one is ready to ship back to you to test on your two LB's. Please PM your name and addy and I'll get this one back to you ASAP. Upon confirmation on a few measurements, I can modify the second one according to the findings.