Plugging a 1/8" hole exposed to high pressure

[FuzzyGrub]

I need to plug a 1/8" hole in an aluminum block that is exposed to the high pressure in the air tube.  I was thinking of tapping 8-32 threads and epoxy in a 1/2" length pan head screw.   Will this work and be safe?  Any special epoxy I should use?  or other method?

[rsterne]

Plenty safe enough, sealing it is the issue.... I used a 10-32 low profile SHCS with a 5/16" diameter recess milled for the head to a depth of just over 1/8" and an O-ring under it.... No problems at 3000 psi.... and it's easily removable....

Bob

[FuzzyGrub]

I don't have an end mill to make the flat surface for the o-ring.     The epoxy will not seal along the 1/2" of threads?   

[rsterne]

I think it will seal just fine.... my suggestion was to make it removable.... Use JB Weld and you'll break the screw off before it will ever come out....

Bob

[Gippeto]

IMO, an 8-32 grub screw of 1/4" length would suffice...would seal it with blue loctite.

I use blue loctite on all my fill fittings...leave it overnight. Easy to dis assemble if needed, and blue loctite is available darn near anywhere.

Al

[FuzzyGrub]

I think it will seal just fine.... my suggestion was to make it removable.... Use JB Weld and you'll break the screw off before it will ever come out....

Bob

Thx Bob, I have JB Weld.   There is no need to remove it.  Just plugging a mistake.   

[FuzzyGrub]

IMO, an 8-32 grub screw of 1/4" length would suffice...would seal it with blue loctite.

I use blue loctite on all my fill fittings...leave it overnight. Easy to dis assemble if needed, and blue loctite is available darn near anywhere.

Al

Have you had that hold against high pressure for extended time?  I have not used it to seal in high pressure applications.   I have both blue and red, but thinking I like the epoxy a bit more, for longevity. 

[Gippeto]

I use it on the foster fittings on pcp builds...these are exposed to long term pressure...I've never had any issues.

Also use it on my fill fittings/whips...neat and tidy.... no strings of teflon tape floating around.

Al

[HillGSA]

Talking about sealing power of;  Pounds Per Square Inch,

e.g.,
small 1/8" x 1/2" set screw, etc. with locktite = no problem,

however if it were say 1" or larger, then you could have a problem.


Just to make sure though, when you go to fill, be sure to point it in the direction of
a squirrel. 

[Gippeto]

small 1/8" x 1/2" set screw, etc. with locktite = no problem,

however if it were say 1" or larger, then you could have a problem.

Care to explain your thinking on that one??

Al