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alpinelakespilot2000

Well Known Member
Was replacing some hardware store screws with some stainless screws on my Dynon pitot and mast when the head broke off. No, not on the hardware store screw, on an ACS stainless screw! Wasn't even cross threaded or anything! Needless to say, that batch of ACS screws will be going into the trash! Anyway, for a screw that small, is there any way to extract the shank if the head is missing? Open to all suggestions b/c I'd prefer not to have to drill a new (5th) hole in my mast and pitot tube.
Thanks.
 
Stainless Screws

I've broken many more stainless screws than cad plated.

If you can get to the back side of the screw, a tiny pliers can turn the stump out. Otherwise, very carefully drill the center out and use a tiny needle nose plier to back it out. A squirt of lubricant might help loosen it.
 
Gotta agree on stainless-------just plane junk IMHO.

If you plan to use them, use a bit of beeswax to lube the threads.
 
Screw Extractor

Sears sells a nifty set of Double ended screw extractor/Drill bit for use with a battery drill. On side is a left handed bit. The other will bit to extract the screw.
I am not sure if they will work in your situation however they really shine when removing a screw with the head rounded out.
The sets are sized n two or three size ranges.
 
6-32 not so good of design

6-32 is a course thread:eek:
6-40 is a fine thread :)

The common use for 6-40 is Pitot Tube mounting and some instrumentation.

6-32 is much weaker because the minor diameter is so much smaller. To make matters worse the Aircraft Stainless is a minimum strength of 80 ksi tensile strength. The commercial look alike may be equivalent or less:eek:

My preference of 6-32 screws for anything remotely requiring better strength (140 ksi min.) are Cad Plated Steel, the NAS601 (Pan head) and NAS514 (Countersunk) So if you get aircraft stainless it might be better than commercial stainless, no guarantee for commercial non aircraft stainless.

Getting any 6-32 screw out after breaking the head is a mechanics lesson in severe amounts of patience.
It is best to use a fastener that least likely to break. Best wishes with all the functional suggestion one or more will get it out. You may just have to take out the nutplate.
 
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from a fastener website:

It is a common misconception that stainless steel is stronger than regular steel. In fact, due to the low carbon content, stainless steel cannot be hardened. Therefore when compared with regular steel it is slightly stronger than an un-hardened (grade 2) steel fastener but significantly weaker than hardened steel fasteners.

This is why you NEVER replace a structural screw with a stainless screw.

bob burns

N82RB RV-4

tom posted even better info while I was typing this.
 
When you drill the hole for the screww extractor you should drill it with a lefthanded drill bit. Nine times out of ten the screww will back out as you drill and you'll never take the extractor out of the box.
 
6-32 pretty small but is there any way you could cut a very thin slot into it without doing much damage to the body of the pitot and using a fine screw driver to remove the screw.
 
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