Cheap and Effective Battery Sleeve to fit 16mm Batteries into 18mm Host

I have a couple hosts that accommodate 18mm diameter batteries but barely have enough room (depth) for two flat top 18350 batteries. I can only get a couple threads of the tailcap to bite the fit is so tight. One of my hosts is this beautiful build by Eghemus.



With two 16340 batteries all the way in, see how they are already flush with the outer edge of the host leaving only whatever you can compress the spring inside for use by the tailcap threads.



I have the same issue with (mechanical mod) vape hosts designed for one 18650 that comes with very little extra room. So my plan was to use two 16340 batteries instead which together take up 68mm giving me 2mm to work with versus using two 18350 batteries. For hosts with space for (nominally) one 18650, I only need an extra 3mm versus using two 18350 batteries which would require an extra 5mm. Sleeves allow the batteries to be snug and centered which can avoid connection issues. Thus the search for sleeves.

I looked everywhere for 16mm to 18mm sleeves but could only find these at Oveready and one sleeve to accomodate two batteries costs $14. They mostly worked but, in addition to being fairly expensive, the sleeve doesn't have both ends fully open thus 'took back' some of my 2mm slack due to the thickness of one of the closed ends. Here are closeups of each end of the Oveready sleeve.



Searching again I found some advice in a flashlight forum to use spiral wrap (or wrapping) commonly used for neatly bundling loose cables together. After buying a few sizes, I found the better quality spiral wrap was too thick. I needed the thin walled cheaper variety. I found these at a local swap meet, 30 feet for $5, that work great. The picture below shows two different thicknesses and the label on the bag of the ones that worked and two 16340 batteries in the spiral wrap.



Also found some from tibdealz on eBay at $6 for 20 feet here. It was also the thin walled type and works great. Here is a picture of the auction.



Hopefully it'll help someone here on LPF. I spent a few weeks and a few bucks buying and trying. And I'm sure Google will find this post soon enough hopefully saving others down the road a lot of time looking for a good solution.

EDIT: Added another picture and updated eBay link to latest auction

Great info OVNI! I appreciate you posting this for us! +1

OVNI----go to the hardware store and get some o-rings of the right size and thickness to on the 16340s and hold them centered in the host----works great--small cost ---2 or 3 on each battery

Hi,
ehgemus uses a plastic contact board in his builds, if you look inside the battery tube you see a spring. To get that out you need to disassemble the unit from the module and driver first. Then you will see the two contact wire connected to the insert, get e piece of 1/2 pvc and push the insert to the tailcoat and out. there you can trim the spring so two 18350's will fit.

Rich

Thanks everyone for the tips and help. I should've posted the problem before I got started, sounds like it would've saved me some time. Well 50' of spiral wrap should last me for a while.

You can also easily make your own with paper and what is really nice is photo paper as it is thick and makes a really nice tube. I've been doing that for a couple years now. Just fold it around the batteries just tight enough so that the batteries can still slide easy enough and then just use a couple pieces of Scott tape.
You can go to an auto parts store and buy a long roll of this clear thick film that is used to stick against the vehicles bottom edge to prevent things like rocks from damaging the paint. It comes rolled onto a piece of thick paper like the photo paper so you can cut off a piece of the paper and roll the clear piece the opposite way so that the sticky is not against the battery and then tape it to itself in the one small strip of it where you removed the paper from.
I can't stand battery rattle. Nothing in a build should rattle. I will eventually be posting Pman build stuff all in one thread with stuff like this.
If you need to take up a much larger space then you can buy radiator hose that will fit over the cell or split the hose and it will self clamp over the battery. I'm pretty sure they sell it by the foot and it's relatively cheap.
Did I mention I can't stand battery rattle