what kind of glue?

[MarkT]

I have a Butler Creek flip-up see-thru scope cap that won't say closed.  Want to glue it shut.  It's rubber.  I put a good amount of silicon "Goop" on the inside edge, closed it, clamped it shut with a vise-grips and let it dry for a day.  Put the rifle in the safe, got it out a couple days later and the cap was open again. DOH!  I've not seen Goop not glue rubber until now.  It's supposed to be "contact adhesive" among other things.  I don't expect JB Weld or any other epoxies to work because they are brittle and the rubber flexes.  But I could be FOS.  BTW, reviews of Butler Creek caps - this is a very common complaint.

Maybe I'll remove the spring.

What glue works on flexible rubber?  

Here's the item in question.

[henry 008]

tire tube patch glue? just a thought

https://www.motosport.com/product/?adpos=1o2&cc=us&creative=188670675724&device=c&gclid=EAIaIQobChMI1rXC08Xx2QIVETuBCh0PjQL0EAYYAiABEgLwGvD_BwE&key=Camel-Tube-Patch-Kit&matchtype=&mrkgadid=1409982612&mrkgcl=500&network=s&product_id=KML0001-X001-Y001&pssource=true&rkg_id=h-78a12502fb1dea905b1bff9b2eb4f28d_t-1521227402&segment=badger

[Psychotic Bovine]

Not sure, but I would say don't use super glue (cyanoacrylate), unless you want a fogged up lens!
I have had good luck with that stuff that cures with a UV led on some things, but never tried it on rubber.  It's not horribly flexible.
What about Shoo Goo?

[MarkT]

Update - the cap is plastic and the collar is rubber.  I just removed the spring.  I'll try Goop again but don't have confidence in it.  Pretty sure Shoe Goo is the same product as Goop.  They market that stuff as "Marine adhesive"  and "Shoe adhesive" and several other names but it's all the same stuff AFAIK.  Silicon glue.  I use it a LOT and buy it in quantity online.

[Jess from VA]

That reminds me I need to get a pair of Butler Creek (or something) flip up caps for my new .22 6 X 18/40 scope.  I have the Buttler Creek flip ups on a several other scopes, and they stay closed OK, but the springs do seem a bit more powerful than they need to be; when you hit the release buttons.  Sproing!!

The .22 scope came with very fine thread aluminum screw-in caps that offer great protection (for storage, but not for use in the field), and are a big PITA to thread back on without cross-threading, and have to go in your pocket or somewhere when removed.

EDIT:  And now I see this is not going to work in back, because the paralax adjustment is right on the rear edge of the scope.  Maybe one of those rubber bikini covers.

[six2go #152]

How about Elmer's Rubber Cement?

[NautiBrit]

Try a contact cement, the type that you apply to both surfaces, allow to dry and press together. Prep is very important as both surfaces need to be clean and free from dirt and grease and should be lightly sanded to give the glue a surface to grip to.

[oldsmokey]

I've had reasonable luck with Barge Cement.

[da prez]

Tub and tile caulk. It comes in colors.

          da prez

               

[phideux]

Why not just take it off???
What good does a flip up cap do anyway if you glue it shut??

[gregk]

any 100% silacone should work.

[MarkT]

Why not just take it off???
What good does a flip up cap do anyway if you glue it shut??

Look closely at the pic above.  Butler Creek's are transparent - flip up is optional.  Protecting the lenses on expensive Leupolds isn't.  I have looked - can't find another see-thru that isn't really spendy.  Meanwhile I removed the spring and used a lot of Goop - staying shut for now.

[Roidfingers]

Black rtv. from any auto parts store.

[phideux]

Why not just take it off???
What good does a flip up cap do anyway if you glue it shut??

Look closely at the pic above.  Butler Creek's are transparent - flip up is optional.  Protecting the lenses on expensive Leupolds isn't.  I have looked - can't find another see-thru that isn't really spendy.  Meanwhile I removed the spring and used a lot of Goop - staying shut for now.

If you just want to protect the lens. If you look close at the end of your scope you will notice most of them have threads on them. How about going to a camera store and just getting a plain UV filter to screw in????

[mark81]

You could try 3m 5200 marine adhesive. That stuff glues everything. Dont get it where you dont want it. It is next to impossible to get off