Tuning Fx carbon fibre sleeve- to glue or not to glue?

I just installed the FX CF tube over my 700mm .30 cal Impact liner. It was quite tight and I saw no reason to glue in on. While I agree with Qball about the value question ($30 tube on a $2,000+ airgun) my reason for not gluing nit wasn’t to save money and reuse the liner. It was just a lot easier to see how things worked with, and without, the liner if I didn’t glue it. After seeing how tightly it fit (and how well it shot) I didn’t see a reason to go back in and try it without, or to modify it by adding glue.

By The Way, it was so tight that I had to remove the STX Superior label to get it to slide on. It also just shot perfectly (repeatable one hole groups at 25 and 50 yards). Of course, it was shooting fine before as well 😎

On a SuperLight barrel, like the Crowns have, I might be more tempted to use some form of glue, since they don’t have the relatively tight fitting outer barrel tube to go over the CF tube/liner combo.

Chris
 
  • Like
Reactions: KodiakJac
I glued my FX liner on my 700mm sniper barrel. I used 2 part epoxy. The FX liner was nice and tight fitting but any space is still space. I cleaned the liner with CRC contact cleaner and mixed some JB Weld 2 part clear epoxy. I lightly coated the liner “only where the sleeve would contact” with the epoxy and slid the sleeve on while rotating it making sure to get full contact of epoxy between the sleeve and liner. As it was already quite tight a lot of the epoxy was pushed to the end where I cleaned it off with more contact cleaner and a rag. Then I set to cure and now it’s stiff as a nail. I really don’t see how not using epoxy could be of any advantage. 
 
  • Like
Reactions: Amink66
My liner had OK'sih fit, when I let it drop by gravity into CF sleeve it fall inside hole almost the entire length and I could help it slide in with a gentle one finger push.

I wrapped the liner with a "blue=thinnest" teflon tape a single layer not to over lap, and slide into the CF sleeve almost all the way in, the very last maybe 1/4 length I had to put my weight in to push it against the floor. That thin layer of tape have a little "give" on any minor gaps inside - from fabrications, and I am happy with results.
 
I glued my CF sleeve on my 700mm barrel on my Maverick Sniper but I didn't use two part epoxy. I cleaned the oil film off the barrel then used Locktite which sets up fine. (You don't use silicone caulk or such because they cure by atmospheric moisture and so the end inches cure but the middle never does). I think it's easier to clean up any excess than epoxy.

Pick the one that's right for your gap:

LOCTITE 638 is a high strength, fast curing, general purpose retaining compound designed for the bonding of cylindrical fitting parts, particularly with narrow bond gaps approaching 0.25 mm (0.010 thousands)
LOCTITE 648 is a low viscosity, high strength retaining compound (green)
LOCTITE 660 is a high strength retaining compound with good gap filling properties (0.010 to 0.020)

FYI - I used the 648 because my FX sleeve had a very snug fit on the barrel.

Note that these are 'retaining compounds' NOT thread locker which have different part numbers.
 
Did you find any improvments in accuracy?

If you're asking me due to my above post?



Understand that I didn't do any before and after testing BECAUSE I've had several other air rifles in the past that I did test and saw that glueing / securing the CF sleeve was the better choice.

So when I got my Maverick I didn't test it factory condition (besides airing it up and test firing it a couple of magazines to make sure everything was functional), I just installed all the upgrades like slug kit and sleeving and am developing tunes from that base.



I'm not planning on ever using the Maverick as a pellet rifle, it's a dedicated slug gun.
 
Thanks for replying, yes i just was wondering if you did any before and after tests, when i fitted my carbon fibre sleeve i did some tests myself and didnt notice much difference.

After reading your response i may well glue it with the method you described and use one of the retaining compounds you have recomended, my sleeve was found to be a friction fit so locktite 648 will probably be the best choice.
 
  • Like
Reactions: tentman
I put a CF barrel sleeve on my FX Crown MKII 600 mm barrel. 

The OEM crown barrel/shroud spacers will not work once you install the CF sleeve. If you do not use spacers, you may damage your moderator. (Ask me how I know).

So I riffed on a design another user uploaded which did not work with my FDM printer, and this is what I got:

longblacktapedcf.1651347439.JPG


Initially I used electrical tape to prevent the CF barrel sleeve and spacers from getting stuck in the shroud.

But eventually I decided there was too much slop, and it was too much of a kludge, so I used Infinity bond EP 420 high peel and shear strength epoxy from gluegun dot com. I already had some for RC modeling. It is very slow curing so I let it sit for a day.

3onSleeveLongBlack.1651347512.JPG


These are working well for me and some other users. The epoxy is very strong and I do recommend with the following caveats.

Whether you decide to epoxy or not is up to you. I am a relative newb at this stuff but I figured worst case I'd have to buy a new barrel. But that is a big gamble I was willing to take, and may not be a gamble you are willing to take.

Anyway, I now have them in three colors (the prototypes):

singleBlue.1651347600.jpg


singleYellow.1651347600.jpg


threeColors4.1651347600.jpg


PCP-FXCF-LONG-BLA-25-30-ORING.1651347600.jpg


Like I said, on the crown, these CF sleeve/ FX shroud spacers are essential on the FX Crown in my experience. The cost of learning this was damage to DonnyFL when I did not use the spacers.
 
I just installed some of bd2021’s spacers last night. I can say that I got a very good fit, and this is the most confidence I’ve had in this barrel set up, my 500mm Crown barrel with carbon fiber sleeve. I used 2 of his spacers, and just came in from hitting my spinners at 97 yards, dare I say easily, in calm conditions. Thanks again Mike!
 
  • Like
Reactions: KodiakJac
For those STILL wondering -

THINK ABOUT IT...FOR JUST ONE SECOND...!!!

IF...there is no "SOLID", 100% contact between the barrel and the, said, "stiffener"...WHAT USE IS IT ? It's useless, makes your gun look supposedly, pretty.
If there is no full contact "support" (look up the word !), the barrel will just vibrate around inside of the sleeve, like,...it isn't even there...right ?

Mike