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Lamp helmet mounting?

Timwillows

New member
Hi, I have finally upgraded my ancient caving helmet to a shiny new Boreo, so now need to move my lamp across and wanted to check the communal wisdom on the best way to do it. Lamp is a first gen Rude Nora, working well so no plans to change, it is mounted to my old helmet by three bolts to hold on the lamp bracket and four holes for zip ties to secure the battery box. All fairly easy on the old helmet, but the Boreo is foam lined so I’ll need to work through that if I’m to duplicate the old system.
Any better ideas for mounting before I get the drill out?
 
Thanks for that, a useful guide. I’m still unsure how the foam interacts with it zip ties that hold the battery box in place. Do they simply cut in and effectively loosen over time? At the front the standard fitting point would put the bracket holes very close to vents, potentially creating a crack line, so wondered if anyone had used a single bolt and zip ties through the other two
 
I managed to get a Nora 3 mounted to just the Boreo shell. The foam lining pops out if you remove the chin strap attachments. I think I found a video from Derek Bristol that shows how to remove it all. From memory you’ve got to press down with a flat head screwdriver to release the catch on the inside of the rear attachment point. I initially tried to carve a route into the foam for the cable to to follow between the shell and the liner but it was impossible to find the right routing, and eventually I went for the brute force route of squeezing the liner back in until the chin strap clips sat back in place. There is now a 5mm gap between the liner and the shell on one side of my head, that I’m certain if you were to do enough testing would show that it has weakened by XkN (my argument is that if I’m needing the additional few kN of these fine margins, I’ve probably got bigger problems.

Disclaimer: Petzl say a) do not remove liners from helmets and b) do not drill holes into helmets. Any of this is done at your own risk, and will certainly invalidate any warranty - likewise it should not be used in a professional sense. It might also be prudent not to ever lend it to someone - at least not without a strong warning that it’s questionable PPE. None of this disclaimer has stopped me doing it though for lack of other options.
 
3M's VHB (very high bond) two-sided tape is insane. They make it in different thicknesses too - I'd suggest going with one of the thicker options, so as to offer better contouring to any curved surfaces.

Skip the bolts. They won't be needed with the VHB tape. Add zip-ties for any added peace of mind, but they still probably aren't needed...


Edit: I see now the type of mount you're trying to affix. You probably DO want the screws for the light mount. The battery box however, you could almost certainly get by with just the VHB tape, as there's a lot more surface area for the tape to bond to. Add the zip-ties if you wish.
 
3M's VHB (very high bond) two-sided tape is insane. They make it in different thicknesses too - I'd suggest going with one of the thicker options, so as to offer better contouring to any curved surfaces.

Skip the bolts. They won't be needed with the VHB tape. Add zip-ties for any added peace of mind, but they still probably aren't needed...


Edit: I see now the type of mount you're trying to affix. You probably DO want the screws for the light mount. The battery box however, you could almost certainly get by with just the VHB tape, as there's a lot more surface area for the tape to bond to. Add the zip-ties if you wish.

still not sure Id trust it myself, last thing u want ascending a waterfal is for lamp to be ripped off
 
still not sure Id trust it myself, last thing u want ascending a waterfal is for lamp to be ripped off
I've messed with the VHB tape in some industrial applications, and it is thoroughly impressive. The only thing that seems to damage it, is exsposure to oils, or extreme agitation. (We were using it on an industrial robot's grippers, and it did OK until we could find a better solution to that specific problem.)

Fenix includes a patch of this VHB tape with their headlamp mounting kits. It's used to attach the quick-mount to the helmet itself, and baby, IT STICKS! :LOL: I did choose to install zip-ties, but moreso to keep secure the light & mount from un-snapping and falling off, not so much to backup the tape itself. Without hesitation, I would say that the tape is more secure than then snap-detents of the light mounts - which is the real reason for my zip-tie backups.

I agree that screws are best for THAT light mount, as that mount would place a lot of leverage on the tape alone. However, I'd be very trusting of the tape for the battery box. That's a lot of bonding surface, and not much leverage. Even just a couple well-placed strips at the edges of the box would be enough, and likely would conform well to any curvature of the helmet.
 
VHB tape has failed to stick a camera to the inside of a car windscreen for me, probably due to the heat of the sun on the screen and the weight of the camera (although it wasn't very heavy it was levering on the fixing). If I wanted to avoid drilling to fix a bracket like that for the Rude Nora, I'd bolt the bracket to a plate and then VHB the plate to the helmet.
 
I had a similar problem moving too mounting a filthy edna (same front mount as a Nora I think) to a Boreo. I used a souldering iron to melt holes which seemed easier than drilling the expanded foam (didn't realise I could pop it out...). I originally mounted the lamp low down so the holes weren't close to the edge of the shell but that was an irritating place to have the lamp so put new holes in which are close to the edge but it hasn't cracked (yet!) and seems solid enough.

The irritating bit I found was how to route the cable, in the end I gave up and just routed it on the outside with some cable ties around the shell (between the expanded foam and shell) to keep it in place. If useful I could probably post some pictures?
 
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