Hi,
I've got a Naish fuselage,last years model,now when I change front wings tighten up the the 3 30mm Phillips head screws they come loose within 20 mins of use????I use all naish foils.
Ive tried screwing them tight but nothing works,only just started happening.they're not cross threaded
Should I replace them with torx head screws???
wierd
I used phillips heads on my previous foil, as it didn't come with any. Using TefGel certainly helped them stay in but I could never get the Phillips head as tight as I can with the Torx heads on my new foil. The Torx are less prone to stripping the head too.
Strange, I use grease on all my connections and screws of my Naish foils, rarely do I find a loose one. I have replaced all the Philips with Torx, I just buy the security ones from Bunnings.
My advice:
- use Torx heads.
- get Titane screws. They are both much more durable than stainless steel, harder, and are less prone to galvanic corrosion (less galvanic potential difference with carbon)
- get a dynamometer wrench so that you are sure to screw at the max safe torque (around 5 N.m for my brass inserts)
- always use some tef-gel to avoid galling (esp. with titane screws) and galvanic corrosion (esp. with alu foils)
If all else fails, use non-permanent thread lock (red locktite) instead of tef gel.
I use some vaseline grease, works like a charm. Always had screws coming loose when jumping, now I dont have that problem. Additional benefit: when a screw snapped I got the left over bit out of the insert very easily!
Thx for all the advice,helpful site this.
off to bloody Bunnings, never thought about them having screws for foils, pretty dumb really ,Bunnings has everything.
look at buying some loc tight
vasaline seems like a good idea,although I'm to old and slow to jump,still learning switch foot gybes.
thx again for your help.
Red is the low torque loctite, blue is medium and green high strength. Blue 243 is what to use if needed, but Vaseline has excellent corrosion resistance and you foil will stay looking new. I've actually done some testing and Vaseline is as if not better than marine grease.
Here are the screws I use, yes they have the security dot in the middle but a hex bit is supplied. I grind the dot off, just in case I don't have the security bit in my screwdriver.
Blue is the one to use.
But i prefer TefGel.
Blue Loctite will leave buildup of dried up gunk in the threads and eventually it gets hard to "feel" if the screw is going in right or crossthreaded.
Tefgel is sticky but always soft.
I'm a big fan of the Torx security screws. The socket in the head is about twice as deep as plain Torx or hex heads and the pin helps to lock the tool into place.
Because the connection is so positive it's easy to gently tighten the screws to whatever tightness you want and the screw heads never wear out. Hex and plain Torx can allow the tool to slip so there's a tendency to overtighten because you have less control over the tool.
I use a T-handle wrench for my Torx screws. The weight of the T-handle spins the screws in and out very quickly and I can easily gauge the tension with finger tips. I've used torque wrenches in the past with hex screws and found the slipping of the hex screws a problem.
The only problem with Torx security screws is the countersunk screws only come in food grade 314 stainless. All my foils have Tuttle connections so there's no need for the added strength of 316 stainless. All the load goes through the structural connection. The screws are more for security.
I keep several Torx pin tools in the car and my foil bags have pockets with spare screws and keys so there is very little risk of not having the tool I need.
All this is a bit of a moot point. Using Torx security screws is much more about convenience and reduced wear on the heads. There should be no need to tighten screws super tight. Hand/finger tight should be sufficient. Maybe look at the grease you're using or some loctite.
I am constantly amazed at the amount of knowledge you guys have.
the fact that your willing to take the time to help.
I for one appreciate it,thank you
316 stainless has better corrosion resistance than 304 so is preferable. But 316 torx are difficult to buy in Oz so I've been using 304, no corrosion pitting evident over several months use.
Oops, my bad, yes, it is the blue loctite to use.
I guess I was thinking "not the red" when writing my post.... so I ended up writing "red" :-)
Fitzsup, we learn from our errors, so this means we made lots of mistakes... and still do!
Select to expand quoteKraut said..
I read that Teflon tape may also work but haven't tried myself yet
Now that you mention it, I have switched from teflon/PTFE tape and traditional yarn for threads on water pipes to the more modern plumbing thread resins ("Anaerobic resins"). It may be a solution if you do not plan to disassemble your gear often and loctite is not working.
www.luokeadhesives.com/news/anaerobic-resin-compounds-vs-teflon-tape-vs-pipe-dope
