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24 Posts
Discussion Starter #1
The following is a D I Y how to repair stress cracks in the rear barn door.
I have made this a two part process. Step 1 and 2

Step 1.

As per this Pic.

I have read the posts where members have had to remove the rear window to achieve this fix. This is mainly due to the fact that the stress crack was far worse than mine.
The trick here is to catch this problem before it gets worse. I would suggest that if you intend on upsizing your tyres then defiantly make this a must do....

OK back to basics...
Allow approx. 4 to 6 hours to complete.
Tools needed..

Mash Hammer. ( Heavy hammer )
Welder ( Mig is preferred )
Small angle Grinder
Electric Drill
Drill Bits 3mm and 8mm
Star Screw Driver

Start by removing the inside door trim and skin.
Take care when removing the plastic fixings plugs.
Carefully remove the plastic dust cover from the right side of the door.(This will be used again )
Remove the wiper blade arm from the outside of the door.
You are then able to remove the three bolts holding the wiper motor to the inside of the door. Carefully take the motor assembly off the door.
Remove all wiring that leads up the centre pillar.
Remove the locking mechanism from the top of the door and the rod too.
You should end up with this..

The next step.
Material needed.
20 x 20 RHS 400mm long.
30mm x 3mm Flat 400mm long.
20mm x 2mm flat 2 @ 200mm long.

Take the RHS place it over two pieces of timber ( Like a Bridge ) and form it to suit the shape of the door as per pic.

What I did from here.
Welded 20mm flat approx 200mm long to the top of the RHS.
I did this so the RHS will be flush with the existing support.
As per this pic.

The 30mm flat is welded to the side if the RHS for support, you will need to shape this to suite the angle of the RHS.
To understand this fully you will need to study the area where this will fit, take note of the existing reinforcement the RHS needs to be packed out to fit tight.
Looking at the door from the inside, the RHS is bent to shape with a packer at the top and one at the bottom right side. The 400mm flat is welded on the left side and trimmed to suit the shape of the door cavity.

Sorry I forgot to take a pic at this point..:(

You will need to test the fit. Once you are happy tap it into place so that you end up with 200mm above and below the crack.
This pic gives you an idea of the final fit.
Note this pic was taken at the last stage. Do not fit the wiring or door hardware yet !!!

Now its time to Drill some holes.
We are going to setup for the welding of the RHS to the door frame.
You will need to drill holes through the door into the RHS taking care not to drill through the RHS. I used the small drill as a pilot hole then the larger drill bit.
Here is what it should look like.

Please go to next post for step 2.

24 Posts
Discussion Starter #2
Rear Door Repair Step 2.

Rear Door Repair Step 2.

This next step is achieved by using a mig welder. This is preferred as it can be set to weld thin steel.
The object here is to fill the holes with weld making sure you weld the RHS first then start to fill the hole. (This is a form of spot welding)Be careful not to burn the metal, try making small welds allowing it to cool and then welding again until all the holes are filled. It should look like this..

Grind the welds until level with existing surface taking care not to throw sparks towards any glass surfaces.

Apply Body filler.

Body filler sanded smooth ready for paint.

The final job should look like this viewing from the inside of the door.

Note that I have positioned the top lock rod through the RHS and made some slight adjustments to allow it to operate smoothly. The wiring to was installed back the same.
Now all you have to do is put the Hardware back onto the door and refit the trims and your done.
If you have any questions please feel free to contact me.
Regards Nuke.

38 Posts
Barn Door Cracking

Hi Nuke,

Following with interest your steps to repair the crack. I know it's only recent, but how is the widest crack adjacent to the black window strip holding up? That is the bit that concerns me. Need to repair mine soon.



nissan patrol gq
304 Posts
Hi guys/gals,
I too have had the crack of death in my RHS barn door and came across this DIY as well as another on an other site.
I set out to carry out this repair but only had a stick welder. I got a few plugged up top and down low but it was getting a little too hot for the thin gauge metal. I opted for pop rivets to hold it everywhere else and it has worked great. So if, like me, you don't have a TIG/MIG pop rivets work just fine. You'll have to spend the extra time getting the bar shape exactly right but may make things easier for you.

60 Posts
Big thanks for this thread :D

Fixed three doors in the last two weeks. The one on my car, one on a friends and one spare. Have access to an experienced welder (son), Used TIG on the crack to keep heat down near the window and MIG on the plug welds. Wet rag to cool after each weld.

As I said, this thread is a great guide, and thanks again.

Regards :)
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