I’m trying to make a sleeve for my DST to hold 18650’s. I bought some pvc pipe, but it’s a couple mm’s too thick for the DST. Is there a good way to trim the diameter of the pipe? Sandpaper is taking forever and making a terrible mess.
Otherwise, is there a good source (preferably US) for 26650/18650 spacers?
If you have nothing, make you one out of rolled-up paper.
I used this for my 3D Mag with Triple P7 back in the day 
Use rubber o rings. Two per cell.
Available in PlumberSupply for cheap. They prevent rattling and work perfect.
One thing to try is to buy an inexpensive ( Harbor Freight or the like)
kit of O-rings of assorted sizes.
You may be able to find o-rings whose ID could allow it to slip onto the 18650
and act as an adapter/spacer in 26650 lights.
Not a US Vendor, but FastTech has the adapter sleeves for $1.26
https://m.fasttech.com/product/1235202-18650-to-26650-battery-converter
There is a thread devoted to the DST. 1200 replies, all kinds of info including the spacer.
Are you referring to your post, #216?
The pics aren’t showing up. Does this water pipe go by a different name? PEX maybe?
I’d rather have a sleeve/pipe thing than o-rings, just for easier battery changes.
Edit:
The second pic is a rig for running 2 18650’s in parallel. Thank ImA4Wheelr for that one. The sleeve holds everything together in the light.
And btw, I trick I use from time to time when stuff like this happens (missing pics etc) is to quote the post and then you can see the code that is imbedded. I merely did that and copied and pasted the links to my pictures.
Even with your reposted links they don’t work on my phone, it just redirects to your full list of pics. On my desktop it works ok though.
With that pipe is there any rattle at all? Or is it pretty much a perfect fit?
Try using a cycle inner tube, that’s what I use anyway, just cut it to the right length and slip it over, I used a MTB one but a BMX one would probably be better for a tighter fit over the battery
To me these work the best—-fit is nice—SB had them for $2 but appear to be out—here they are at Customlites
http://www.customlites.com/Shadow-18650-sleeve-for-26650-batteries-Sh-26650-slve.htm
Perfect fit, no rattle. OD and ID are just right.
Ouch! 
Ace Hardware, 3/4-inch irrigation pipe. Buy it by the foot,cut to length, slit lengthwise moving as much as needed to sleeve the cell without overlap. Works great, cheap! it was ~$.60/ft the last time I bought it there.