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Fill Holes During Flight

Fill Holes During Flight

Fill Holes During Flight

I have several counter bored holes on a component I've designed. The front of the part has a 60 degree slope and the back of the part is flat. So I have to drill counter bored holes through the top of the sloped surface and put nut plates on the back of the mating component (which is flat). After they install the hardware I need to be able to fill the "counter bore" during flight but I also need to remove the hardware after the flight is over. So I have to fill the holes or cover the holes with something that is not permanent. Any ideas?
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RE: Fill Holes During Flight

For a test flight, if you are not going to encounter any rain , you can use spackling putty of the type used for patching drywall, when you are done you can flush it out with a hose, or just dig it out with a sharp edged tool . Or you can just use 600MPH metallic tape if the resulting dimples do not bother you.
If you are going to encounter rain , spackle the holes then lay 600mph tape over the top.

You are judged not by what you know, but by what you can do.

RE: Fill Holes During Flight

plastic plugs ?

possibly use blanking plates to fill the CB, and attach with a screw into a tapped hole in the head of the fastener ... I did say "possibly" ...

especially designed hardware ... with a head to fill the CB and an internal wrenching head/tool

speed tape is a really good idea ! for flight test, but what'll you do for in-service ?

another day in paradise, or is paradise one day closer ?

RE: Fill Holes During Flight

IF there is any significant speed/pressure on the plugs, then 'anything' low-adhesion/soft will be difficult keep from 'blowing away'.

My approach would be to clean the CBs carefully, after parts installation, then fill the CBs with low adhesion sealant AMS3267 or PPG/PRC equivalent. When the sealant cures, then the surface has high strength/resilience... just not much adhesion to the CBs.

Caution: if there are substantial air-voids below the plug surface and no way to vent pressure at altitude [delta-P], then those voids may cause the plug to be breeched/pop-out.

'Speed tape' = Aluminum foil pressure-adhesive tape typically '3M' [MMM] Aluminum Foil Tape 425 or 427 [can be certified to meet AMS-T-23397 & L-T-80]

Regards, Wil Taylor

o Trust - But Verify!
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