How would one mill the plastic overmold height of a thick USB3 connector?

[WobblyHand]

Offbeat question. Background. Laptop died. (Power supply on MB.) Waiting for new laptop to arrive... Don't even have an estimated time of arrival. Temporarily using a Raspberry Pi 4 (RPi4) as a primary computer. Once I was able to boot from SSD, it isn't too bad.

Problem is 1) limited number of ports on the RPi4, 2) spacing of ports on the RPi4, and 3) USB male connectors don't seem to have a standard height for the plastic overmold.

Basically, the adapter I need to use has a non-standard thicker connector. We are not talking super thick, but thick enough to interfere with the connector below. So thinking out loud here... All I need to do is mill off a little from the plastic connector, until I get a fit.

The stacked connector spacing on the RPi4 I measure to be 8mm, or 0.315". I have 2 cables which measure 0.370 and 0.331. The thicker one is attached to a USB3 to SATA adapter, that's my SSD. The other is for a small unpowered USB3 hub.

How could one hold the male connectors tight enough to mill? Other things to watch out for? I do have a fallback for the disk. Have an external disk housing that I can pop the disk into an run. It's slower than the plug in adapter, but workable.

 

[Larry$]

Try sanding it a bit at a time until it fits, or fails.

 

[WobblyHand]

Try sanding it a bit at a time until it fits, or fails.

My takeaway from your response is that it would be a bad idea to put the connector end in a mill vise. Not sure I disagree. That's why I was asking. Have to say, sanding seems so anti-precision, if you know what I mean. Just tried sanding. Mmm, no. Plastic and sandpaper, uggh.

I think it will be ok. I'm going to try milling one of the connectors. The one with the least amount to take off. If I screw it up, it won't bother me. I'll get practice holding it in the vise.

Reporting back. Success. Used a 1/8" eBay special carbide mill running at 2500 RPM. Took off 0.005" on both sides. Total thickness at 0.314". As I was laboriously milling off a little at a time, I thought about a fly cutter doing it all at once. I'll stick with the little end mill for now. If I had practice pieces, I'd be more daring.

Well I'm going to try the fat connector. Be back, hopefully with success. If not, well, I'll just eat crow.

 

[matthewsx]

Exacto knife

 

[WobblyHand]

Success! Now the two connectors fit on top of each other without interfering. Only loss was the USB logo on the fat one - it was completely milled off. It's great to be able to fix these little annoying things. The thicker connector still has enough meat on it. It's not soft on the sides, like it would be if it was about to blow through. Have no idea why they made the connector so thick. Oh well, it's not thick anymore.

 

[WobblyHand]

Exacto knife

We have machines, here at hobby-machinist.

I would have used a knife blade if this was flash, or something minor sticking out. I had to take off 0.027" off the top and bottom surfaces of the bottom connector to fit. (0.054" total) I wanted it to fit both on the top or bottom position.