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O.k So I have had a crack in my right barn door since owning the car. For those who don't know, the crack is caused by hanging a larger than stock tyre from the door bracket. The heavy tyre tries to pull the door outwards, hence, the window frame flexes just above where the frame meets the door skin and eventually cracks. Mine was cracked around half way through and hadn't moved, until I hung a 35 off it and it instantly cracked further. So something had to be done. Upon removing the inside door trim I had discovered that it was cracking on the inside too. 20140523_203105 (Medium).jpg20140523_203111 (Medium).jpg
I hunted around for a second hand door with no crack and the best I came up with was $400. No guarantees this door won't crack too...So I bought a Cigweld Gas/Gasless 130Amp mig welder for $350 and I will have this for other projects too...
So gents here is how I went about repairing the crack. I am no expert welder and body repairer to I bloody hope it stays together.
In a nutshell, I curved and slid up the inside of the door skin the RHS and plug welded it to the door...
Tools you will need....
Mig welder
25x25 RHS about 400mm long
3mm x 25mm'ish flat steel about 800mm long
A Hydraulic press to bend the RHS or something else to do the bending
Drill and drill bits
Grinder and flappy disc to sand back the paint on the area to be repaired
Body filler
Spray putty / Primer
Paint
Plenty of time and patience
Welding skills, which I don't have
Body repair skills, which I didn't have either, Lol.
Paint I used was just from SuperCheap. I gave them the paint code and they mixed up a spray can for me. I also got a can of clear for the final coat. 20140528_093648 (Medium).jpg
1. Removal of parts
Inner door trimmings
wiper arm and motor
top locking mechanism and control rod
door catch
door opening handle and mech.
all wiring going up to the top of the door
2. Preparation
I went roughly 200mm either side of the crack and measured and marked it out on the door. Then proceeded to drill 8mm holes down the door staying in the 400mm length, on both corner edges of the door as you will only be able to weld to two sides of the RHS.
This was quite tricky and took a while to get right. Luckily I have a cheap 12ton press I bought and its been money well spent i tell you. I used the press to bend and shape the RHS to the curve of the door. 20140525_175401 (Medium).jpg
To make the RHS nice and tight in the door I welded the flat steel to the side where I was to weld to basically pack it out. After I did that, I was fitting, removing, fitting and removing to still get the contours right. This take a few good hits with a hammer to slide it up the door skin, getting it out was not fun, I had to use a long bit of steel down from the top of the door where the top lock sits to punch it out... Grinding the edges off the flat to suit the contour of the RHS. Finnally the RHS was pretty close. Well good enough for me. Lol.
I forgot to take a pic of the finished welded door. Luckily I suppose as I as I ain't very good at welding. But all I did was slowly weld at the RHS and slowly filled the holes up with weld. Doing this slowly as I didn't want the door glass and rubber to get too hot. I had a wet rag with me and some water to pour over it just incase it got too hot. After a few welding sessions and then grinding sessions I thought it was good enough for me. 20140526_154042 (Medium).jpg
Remember to mask up the back door glass, as I forgot and it copped a little grinding spray and pitted a small section of the glass.
5. Bog and sanding time.
This is another area where I don't shine but I had nothing to lose really and wasn't too concerned as you can see this section with the door shut. So the bog was applied, I waited for it to dry and sanded it back until I was happy with the result.Like my bog skills? 20140526_163840 (Medium).jpg One thing I found is I applied too much bog and didn't sand enough back. I had a though after I had painted it that there was too much bog over the cracked area and I knew the door would still flex a little. The end result was the bog cracked, so I just ran some white Sikaflex over it after the job was finished...
I forgot again to take a pic of my final sanding job put here is a pic of the final spray putty before I painted it...I did four fine coats of spray putty with a light sand in between.... 20140527_150846 (Medium).jpg
6. Final paint
I did around six very light coats with the paint, also with a light sand in between using 800grit sand paper. I could have used finer but thats all I had... 20140528_093710 (Medium).jpg