Is it safe to drill here? (close to seatbelt reel)

[Toxic_Avenger]

I plan to drill a 25mm diameter hole here. It's adjacent to the seatbelt reel for the front passenger on the puma defender 90, and is a convenient location near the battery box, and B pillar of the vehicle. It will be for wiring purposes (installation of a cable gland, similar to what is seen in the 3rd pic below).
I've noticed that the seatbelt reel is bolted to this single thickness aluminium panel, but is also reinforced below with a steel plate which ties it into the other structures under the vehicle (see pic). My planned hole will not interfere with this reinforcing substructure in any way. My main concern is whether drilling a hole in this location might be considered something that needs engineers approval.

Just hoping to get some ideas if this is going to cause any issues, or if it's fair game to go nuts.

View looking at passenger side B pillar. Cross indicates approx location of hole. Bolts are where the reel attaches (reel is hanging in the top of this pic)
http://www.aulro.com/afvb/attachment.php?attachmentid=101301&stc=1&d=1446360966

Sorry about the angle on this one. Looking from LHS door into B pillar area of the 90.
http://www.aulro.com/afvb/attachment.php?attachmentid=101302&stc=1&d=1446360966

Looking underneath vehicle. The plate shown is where the seatbelt reel attaches to the fasteners in-cab. Cross to the left of this plate is approx hole location. Existing cable entry point for winch is also visible
http://www.aulro.com/afvb/attachment.php?attachmentid=101303&stc=1&d=1446360966

[Blknight.aus]

I probably wouldnt go drillin a 25mm hole that near a bend on an ally plate.

What were you planning to grommet out of there or into there, there might be a better option.

[Toxic_Avenger]

Cheers Dave.
The plate itself is flat, but has a bolted edge joint along it's length. Would be easy enough to get to with a drill if need be.

Reason for asking is I've got an air compressor that lives on the wheel arch which has a number of wires which need to get to the battery box (power), and then into the ex box (switching). I am planning to put a cable gland in there with flexible 25mm conduit to allow wires to get from the batery box into the rear load space. This would also ideally allow wiring to get the the rear of the vehicle for other accessories like 12V sockets etc.

Plan B is to use the existing hole in the top of the seat box, and whack a suitable grommet in it... but, I've experienced wire chafing in this area as it bends over the edge joint between the seat box and the flat channel which I want to drill, plus this cable path is a little unsightly. Having a hole tucked away behind the seat belt reel would be perfect for my needs.

[Toxic_Avenger]

More info...

The plate does not appear to be the sole part which is supporting the seat belt mount. The panel itself is a sheet of normal thickness land rover material (1.6mm sheet?) and is folded with a cross section like so:

http://www.aulro.com/afvb/attachment.php?attachmentid=101328&stc=1&d=1446371356
(Excuse my MS paint skillz, or lack thereof).

The panel in question is drawn in black. On the left side, it is bent to allow a bolted join with the seat box. On the right side of it, it folds down and is supported by the chassis outriggers and rear load space floor panels.
The 2 top yellow rectangles are the seat belt mounting hardware.
The red is the underlying support bracket
The green section is the rear chassis tube outrigger...
So on further inspection it seems like all force in the case of an accident is absorved thru that reinforced path, and the sheet aluminium is just 'for show' or minor structural benefit in a crash at best.

[Blknight.aus]

the issue is with the strength of the panel and that the plate you're drilling near is the anchor for you seatbelt.


I'd be putting the compressor in the box with the ecu and rigging an outlet of the compressor on the seatbox.

on the edit of the edit..
I just went and looked at a series.........

I suspect that if I've interpreted your drawing correctly then drilling an inch hole into the piece outboard of the seatbelt mounting plate would be a no no as its not a case of the panel suppoerting the seatbelt mount its the seatbelt mounts pulling double duty to support the panel in which case you're back to you really shouldnt drill that big a hole near a panel fold as it will be weakening what that panel is folded up to support, the giveaway that its ment to have some support and not just a touch fit is that it has the top lip folded down.


whats the percentage of going under the body with a proper metal conduit?

[Toxic_Avenger]

So 1" is the recommendation? I should have plenty of room to work with if that is the case, but it's looking to be a problem that is too complicated to do legally. Not sure what you mean about a metal conduit under the vehicle body though.

To aid the mental tetris, we're looking at a North/south cross section of the area behind the passenger seat on a 90. As it's a late model, it doesn't have the bulkhead behind the seat like some. I've added the battery box in blue.

http://www.aulro.com/afvb/attachment.php?attachmentid=101329&stc=1&d=1446373316

The seatbelt reel is bolted thru the panel I wish to drill. It's main attachment is into the bracket underneath the vehicle, which is in turn bolted directly to the chassis outrigger.

The hole will not pass thru anything other than the aluminium panel (drawn in black)- ie hole would miss the red support bracket.

[Blknight.aus]

thats exactly how I thought it was going...

I would say no as you're working in the second scenario where the seat belt support is doing double duty for the panel you want to drill.

IF you werent in line with the support or so close I probably wouldnt be so worried.

instead of coming into the vehicle through that plate can you run the conduit from under the vehicle up into the wheel arch and coming up through the flat panel of the top of the hweel arch?

[Toxic_Avenger]

Pretty much bang on dave!
When it comes to drill or don't drill, I'll probably stick with my Plan B which was just use the existing hole on the top of the battery box. I'll just need to ensure that the wiring doesn't chafe thru on the lip of the panel like it has started to.

The difficult thing with the defender is it's so fragile when you look at how it's put together. It's all bolts, bends, sealant and a few good prayers. I've got my goals for making it tastefully modified, but need to ensure I'm not causing issues with the critical things like safety in the process. Thanks for your help on this one.

[Blknight.aus]

Pretty much bang on dave!
When it comes to drill or don't drill, I'll probably stick with my Plan B which was just use the existing hole on the top of the battery box. I'll just need to ensure that the wiring doesn't chafe thru on the lip of the panel like it has started to.

The difficult thing with the defender is it's so fragile when you look at how it's put together. It's all bolts, bends, sealant and a few good prayers. I've got my goals for making it tastefully modified, but need to ensure I'm not causing issues with the critical things like safety in the process. Thanks for your help on this one.

you probably dont want to know about some of the new disposable cars that are glued together.

I still think the best thing youd be able to do is use some steel conduit and plastic bends (metal threaded ones if your a masochist) then run from the back side of the battery box stay under the vehicle and then use a 90 degree terminator to seal up on the underside of the wheel arch. Saddle clamp everything in place and terminate at your liesure in a custom flex conduit to a breakout panel you fix to the inside trim under the window.

Hell get uber yuppie and stick a cheapy USB bluetooth dongle onto an audrino board to drive the relays and write yourself an app that will let you drive it from your mobile phone....

[Disco Muppet]

Hell get uber yuppie and stick a cheapy USB bluetooth dongle onto an audrino board to drive the relays and write yourself an app that will let you drive it from your mobile phone....

This ain't no hipster ****...


Sent from my HTC One using AULRO mobile app

[Blknight.aus]

This ain't no hipster ****...


Sayeth the man with the avatar of Kermit quaffing red wine from a glass with a flower on it..

:eek:

[Disco Muppet]

I'm totes doing it ironically, I think. My bath salts haven't kicked in yet.

Sent from my HTC One using AULRO mobile app