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Black_Moons
03-26-2011, 05:54 PM
Hi, Im wonder exactly how hard it will be to remove blue loctited set screws/ hex head bolts? Small ones like #10 through 3/8"

will there be a much greater chance of striping them before they come out assuming they where reasonabley tightend in the first place? (assuming I can't use heat on the part due to nearby paint)

Or is it rather easy to remove like a nylock nut?

Also, what can I use to 'prime' it? (Or find the primer?) I once tryed to loctite some plated screw to aluminum.. few hours later, the loctite did'nt even start to set.

jdunmyer
03-26-2011, 06:36 PM
My experience has been that screws secured with threadlocker ("blue" LocTite) can be loosened with not much more effort than if there was nothing on the threads. They just won't loosen by themselves.

Heat will help, of course. If you need to concentrate it because of paint, etc, try using a soldering iron. Usually, only about 400 degrees is required to break the bond.

JoeLee
03-26-2011, 07:27 PM
It depends on how much was applied to the thread. If it was just a drop in one spot of the screw or the entire thread. Hex head bolts, especially small ones strip easy. Make sure you use a good hex wrench that fits well, you don't want any play when working with small shallow hex pockets.
Heat is always a plus if you don't have to worry about surrounding areas.
What I've done in situations like that is used my big tin knockers soldering iron to apply heat to the head rather than a torch.
The other thing I've done before if a torch can't be used is to heat up the end of a stainless steel rod and then hold it to the hex head for a few seconds, same thing as the soldering iron but a bit hotter and much faster heat transfer.


JL..................

squirrel
03-26-2011, 08:29 PM
I have used blue on my RC heli's but that turned into a mistake because the cheap import set screws will strip out, these are #10 and smaller. Green is better for small things and with import screws, if you have good Holo Krome fastners the blue would be okay.

Black_Moons
03-26-2011, 09:06 PM
Green? Never seen green.. gonna have to get me some of that.

gvasale
03-26-2011, 09:23 PM
there are two kinds of green. 290, which is a compound for assembled fasteners ( apply it to the screw extending through a nut and the like, or to seal porous weld, or sometimes when a light press fit needs a little help) and a heavy duty green which is stronger than red, which is used before assembly. (forgot which number)

squirrel
03-26-2011, 09:41 PM
The green I use is removeable, the bottle is buried in my flight box some where and I cannot remember the number. Its not stronger than red, and the wicking kind is also green. Just looked on Mcmaster's site and 220 is purple, well, I must be lost........

RussZHC
03-26-2011, 09:52 PM
IIRC, the size of the screw and fineness of the thread play a role when using Loctite.
A really fine thread on a large diameter (some sort of "special" say) is quite a bit different than the same thread but with only say 1/3 the diameter.

Moving "up" a grade sort of shifts it from needing a bit of torque to potentially needing a fair bit of heat. I would on occasion use blue on bicycle parts but never red...for the size of most of those threads it was too difficult to remove without heat.

My experience has been the pre-applied stuff, from a mfg and then sitting on a shelf for awhile, is that it to is tougher to loosen...but then I am not convinced it is the identical formulation to what we buy in consumer size bottles (it could of course be a different make as well)

Tobias-B
03-26-2011, 10:06 PM
Green 'sleeve retainer' is the really super- strong stuff.

Purple used to be the low- grip 'aluminum' fastener kind that
got gooey but not actually hard, so you could coax the
fastener out carefully.
It was good for vibration resistance, sometimes when the 'harder'
ones didn't work.

Don't know what they call it now.

t

Arcane
03-26-2011, 10:26 PM
This seems like a good time to bring S&S_ShovelHead's post back up. Any question about what strength what colour of Loctite is can easily be found in the PDF he posted for us.
Any suggestions on loctite products that would be handy around the shop?
http://www.quicktite.loctite.com/us/content_data/LT3722_Maintenance_Solutions.pdf
Im already set on thread locker and retaining compounds.I only use two grades of Loctite, medium strength thread locker...blue stuff...and a high strength stud and bearing retainer...red stuff. The smallest bolt diameter I have used the thread locker on is 1/4", largest 1/2" and I've never had trouble removing any of them. My 250ml bottle of stud and bearing retainer comes from the early 1980s and still seems to be working as good as it ever did as far as I can tell.

Rich Carlstedt
03-26-2011, 10:40 PM
Clean your screws and holes with Laquer Thinner or Acetone.
Use a pipe cleaner in the holes, especially if you just tapped the holes.
For super cleaning, use nitromethane, like dragsters use. The Hobby shop version for model airplanes has oil in it, so be careful.
I have red and blue Loctite that is 30 years old and still works. It has lost some strength ,but still works, just keep it away from heat.
Rich