I've been thinking about drink holders for over a year. Nothing on the market fits a 32 oz. stainless cup and when the dog is in the jeep, there is no place inside.
This is what I came up with:
2 each - Rubber Drain Collar - Femco P1056-33 - 3" x 3" - Lowe's Hardware
4 each - Stainless Flat Socket Head Bolts - 5/16-18 x 3/4" - Ace Hardware
Paracord - For Handles
32 oz Bubba Envy stainless insulated cup
Remove bands from collar.
Use a tri-square,to mark a perpendicular line down the side of the collar.
Find the vertical center of the collar and mark. Then mark 7/8" above and 7/8" below the center mark. You should now have two points 1 3/4" apart.
Added some wood blocking inside the collar and then used a 5/16" leather punch. This left perfectly round 5/16" holes.
Remove the existing bolts from the lower door hinge pin mount. Add some thread locker to the threads of the new flat head bolts and run them into the existing lower door pin hardware. The flat heads flush up pretty well due to the countersinking in the door mounting plate.
The collar distorts slightly against the door pin receiver, but not enough to make a difference and the cup looks perfectly vertical and the holder perfectly round when the cup is inserted. The cup slides easily in and out of the collar and does not rub against the flat heads.
I may add a clear stick-on door bumper on the cowl to keep the cup from touching the body. It is close to 3/8" clear between the cup and the body, but a hard bump or gust of wind might be enough for them to contact each other.
Made a 32" four strand round braid and heat welded it into a loop. Used two 96" lengths of paracord.
Wrapped the loop around the cup and collected the center section into a loop locating the splice in the handle area.
Using a single 108" length of paracord, I collected the two parts of the handle in a king cobra weave.
Using another 108" length of contrasting color, I overlaid the first king cobra weave with another king cobra weave.
Here is the finished product. I placed a self stick clear cabinet door bumper on the body to prevent any chafing.
Hope this helps,