Torque Seal question

[DaleB]

I have been using Torque Seal, per the EAA video, on every nut that I tighten to its final torque spec. In all the discussions I've read here, though, it's only discussed as being applied to nuts. I'm looking at the control pivots I bolted to the F704 bulkhead a couple of weeks ago. I don't know how easy it will be to see the nuts during an inspection, but the bolt heads will be readily visible. Is there any point to applying a stripe to the bolt heads as well as the nuts? Or will the bolts not move before the nuts do? Or is this a pointless question because everything will be readily visible during inspection?

Just curious. I know the stuff isn't required anywhere, but I use it to indicate that I have put a torque wrench on a nut and it's "done".

[Bugsy]

Well I'm not an A&P but personally I wouldn't bother with the bolt head. It really doesn't tell me anything. If the torque seal is intact on the boot head I still don't know if the nut has loosened and if the torque seal breaks on the bolt head I don't know that the nut is compromised. So I didn't bother.

If you just want a idea of what you completed during assembly why not?

[flion]

I only put it on bolt heads that go into nutplates. Used as a marking tool is a good idea, too, so I know what's been done. But pivoting bolts get cotter pins, so they don't need marking, and bearing bolts (like the OP wrote about, which should not pivot) are easily marked on the nut. I can't think of a single bearing bolt where I can't see both ends, albeit the aileron bell-cranks require an inspection mirror.

[clutch22]

If there is a case where you can't see the nut during inspection, and you choose not to torque seal the bolt head then you for sure have no idea if things have moved. However, if you did torque seal the bolt head, then there's a chance it could let you know someday if things have loosened.

That's just my thought on it. You're not losing anything by putting it on.

[flion]

If you can't see the nut to inspect it, how will you put a wrench on it to torque it? As designed, the RVs do not have any blind nuts; where access would be impossible, Van always used nutplates instead. If you are making a modification, you should be sure not to block access or switch to nutplates as required. That includes any fasteners required by your installation. I just added an external alternator regulator to my -6A and had to fabricate a mount with nutplates because it would be impossible to access nuts on a mount attached to the cold side of the firewall (the alternative was to bolt through the firewall, which I don't like to do).

[fixnflyguy]

I am an AP/IA, and wont speak for the "industry standard". For myself, and my RV, I torque seal both sides if visible, which shows any rotation of fasteners even if the nut isn't loose. This isn't really an issue for everything, but I like to know what is moving.