its been a long time in the making, all metal bonnet bulge, none of this crap fiberglass bonnets.
the bonnet bulge was bought around a year maybe lil more ago, $150 from a fella in sydney.
been stored until i got a EF/EL mont bonnet.
some may be thinking, why bother do all the work when you can buy it already done in fiberglass......
well i got nothing agaisnt fiberglass bonnet, but i just want a metal bonnet, i want to know its going to be strong and hold together.... i have trust issues
first off i just got a few pics of one on the other, not finish product...im not that dodgy lmao.
with some luck its off to missus joint this weekend for her dad to sand blast both the bulge an bonnet.
an then start linneing it up ready to be welded in.
and after all that, paint her up an fit her to the car.
if any one interested in this, or got any pointers, please post your thoughts and follow the thread

 

 

Attachments:

Image004.jpg [ 251.87 KiB | Viewed 316 times ]

Image003.jpg [ 365.47 KiB | Viewed 300 times ]

Image002.jpg [ 323.44 KiB | Viewed 331 times ]

Good to see Rach's old bonnet put to good use, I wondered why you wanted another one when you have a white one in the garage Looking forward to see how this all turns out. Good luck with the project!

Cheers
RD

good to see a steel bonnet being made , well done

lol yeh the white one is way to good to use in a project like this. the one you had is perfact, needs alot of work to be back to good nick, so why not give it a make over


yes sir! all metal


a shall post pics as i go along

hey good on ya for going steel.

just a couple of thoughts for u
im a panelbeater / painter and i dont realy like the idea of sand blasting,
the friction and high pressure from the blasting causes a bit of heat through the panels and can cause warpage, especially noticable around the inner bracings, i've seen a few bonnet skins buckled as the blasting on the underside cant get underneath the braces and the outer skin distorts.
also all seam sealing will have to be redone asap as the sand will get in between all joins and will start to rust.
sand also hides in between inner braces and the skin no matter how hard u try to get it out it will still show up in primers and top coats.
are u going to join in the inner braces from the xr8 bonnet too, as in join to the fairmont inners?


i'll be watching this thread with interest
good luck mate

thanks for the pointers mate will be noted down.
umm at this point, im unsure of how im going to do it, a few way you might suggest would be dearly noted being a painter an beater in one

I agree, do not sandblast as you will regret it later. better to use a good quality paint stripper, remember, you only need to strip where you are going to weld as the section under the bulge will be cut out and give yourself 50-75mm clean metal for welding. When I did Troymans Bonnet Bulge iI used gasless MIG 0.9mm wire and found this very effective. When you cut out the Bonnet use thin cutting wheels in a 4" grinder and don't force it through as you will cut the bonnet bracing, better to leave in place at this point. When you are happy with the cut out fit the bulge. I like about 0.5-1mm gap, you will understand why later. Then procced to tack weld the bonnet in, about every 25mm or so. when you have completed this you will find that all the gap has closed up, you may even need to open the gap before completing welding with the cut off wheel. When completly tacked and you are happy with the joints begine welding, only about 25mm at atime per side as it will generate to much heat. As you stager weld around the bonnet the previous sections will cool and allow you to continue, if you feel the bonnet is getting to hot, take a break and let it cool. do not cool down with water as this will cause buckling. If you blow a small hole, leave it and come back later when it is cool and just tack fill it. It is steel so there will be no issues. When fully welded and it comes to grinding the welds, TAKE YOUR TIME, to much grinding gereates heat and heat will buckle the bonnet, do a bit at a time, lightly all the way round till you are happy with the finish. When fully welded you can then cut out the Fairmont bracing and add the BA Bulge bracing if you have it, if not leave the Fairmont bracing in needs the strength, also if you cut out the bracing without replacing it is illegal. Good luck, if you need any further assistance give me a yell.

PS spend extra time getting the dead centre of your bonnet and the bulge and mark it so it stays.

i guess it got a full plan to follow there
thanks heaps for all that info. i will try the way you said no sand blast, i just thought it may of done it better.
but yes i shall follow you instructions and if theres nay troubles ill give you a yell

THANKS HEAPS
im pumped, i really hope it works and hope it turns out looking good

Hardest part is the first cut, all down hill after there. I will see If I can dig up some picks of my bonnet builds and post them for you. will give some idea.

im very happy with the steel bulge..
i prefer all steel aswell..
and when people see it most say oh yea is that one of those fibreglass bulges? and you say no! its all steel..
they usually say hmmm! with a different kind of interest, then ask can i have a look underneath and start asking who did it and was it hard ect...

and paul (swc) i always give you the credit for your welding job!!

Thanks Mate, but your finishing is a top job as well. Funny thing is that I have found the EF/EL bonnets thicker than the EB/ED ones. EB/ED bonnets are a bugger, thin as paper, and always seem loose on the left top corner.

nice reply swc, i sat down earlier and started writing my reply, thought s**t this is gonna take some time so ill have a go later.

its now later...

swc i agree with your way of doing it , only stripping back whats needed. was thinking whether the sand blasting idea was because of bad repairs like crazy cracks and bad bogwork etc or cause it was handy....
i would just use paint stripper on the top of the bonnet if u realy wanted it back to metal to start fresh after the buldge is welded in.

ive got a spare bonnet put away for the same reason.

my methods differ slightly from swc's in regards to welding it in. i would cut the section into the bonnet from a pencilled outline from the bulge. allowing 2-3mm for a final trim up, i like my joins flush. and usually have the new section able to sit and hold itself into the bonnet or whatever after trimming. i use a .6mm wire in my mig and use gas. ive found gasless wire has too much heatsoak into the welds, u can see the discolouration from heat spread about 10mm from the gasless wireand its a filthy looking weld in my experiance. with the .6 wire and using the same method of spotting the welds every 3 inches of so. i try and go for a 5mm spot weld central on the join with equal penetration thru to the other side. i also like to quench / cool the spot after each weld to reduce heat transferred into the panels, doing it this way the heat only spreads about 4-5mm, so less chances of distorting the panel. i go around the area doing this then when i get back to the start i go half way inbetween the welds and so on so on. till the join is a complete bead of overlapping welds basically. takes a fair bit of time just in the welding though. i dolly the panel up in any areas that need it and then get the grinder out.

this is also an area to watch out as swc has said. my preferances on grinder for this is the 3" x 1.6mm disc on the air grinder. use it at 90 degrees to the bead so if the weld is going straight infront of u, u start at one end and slowly work your way to the other end, the sparks are coming off at 90 degrees. this helps the panel stay cooler as the surface area being ground is smaller. i will leave around .5mm proud of the panels just for that bit more strength too. the air grinders u can vary the speed too so the area u are grinding can cool down quicker. only downside is the noise, best done in a workshop as neighbours at home get annoyed pretty easily ive found. make sure u wear hearing protection as well as safety goggles. i have tinninitus , bad ringing in the ears from not using protection, foam ear plugs are cheap as. good eyewear is also a neccesity, over the years i have had my eyes scraped at the hospital around 10 times now from grinding sparks, not nice sitting with your head in a frame and a doc trying to pick bits of metal out your eye with a needle, sometimes takes them 15-20mins of digging the crap out and scraping the rust stains off. some of the eye doctors at local hospital recognise me now. although i havent had that problem in the last 18 months or so.

im not sure whether the actual grinding or the welding takes longer but they are both big jobs.

another thing to think about is the join placement. i usually try and hide the joins under the underside bracing if u understand. i draw up a template of the underside bracing allowing 5-10mm inside the bracing edges so once it is welded in you cant see the joins when u open the bonnet. then place the template onto the bulge underside and mark it out. have to make sure u have it the right way up/around too. then once the bulge is trimmed u can measure and centre it onto the top of the bonnet and mark it out again. then trim the bonnet skin 2mm undersize from the markings ready to fine tune, grind back and make a flush butted joint of the 2 panels.

the final bog work is the easiest. sand an area about 30-40mm each side of the weld with 24 grit disc on grinder and apply the bog. let to cure and block back with 36g, 80g, then 180g all dry freecut paper untill u get it smooth. use some good quality stuff here too, i use 3M paper and let it do the cutting for u dont use too much pressure. keep the sandpaper clean by banging out/blowing off and replace it when the cutting back slows down.

couple of coats of etch primer then quick scuff with 320 and 2pack highfill prime. block back again with 320 wet and dry then 600 or 800 and your ready for paint.

to do this job it would owe me $1000 in labour by the time the bonnet is in primer. a lot of people cant understand the time it takes to get a perfect finnish. i find it realy hard to half do a job, thats why i dont work in a crash shop now

2 similar systems, same result. I use a gasless / gas Mig and find gasless very useful as I have an open area where I weld. I have breathed in enoiugh welding fumes in my trade days LOL. Just take your time with the welding and grinding. There is no rush and a rushed job will look like that. AS Elf said the most important thing is to keep the heat down. The only issue with cooling the joints with water is the cool down is rapid and could make the joint brittle, after all there is bugger all metal in these bonnets. Either way do what suits you. If you have a gas mig use it, if you have gassless there is nothing wrong with that as well. I agree with the method that Elf.. has used with the bog/ filling. If you have areas that need deep filling use fiberglass filler, s**t is a tough as nails and you will need power tools to sand it. In the end the less filler the better. Good luck and more power to you for having a go.

[quote="elf100capri"]
to do this job it would owe me $1000 in labour by the time the bonnet is in primer. a lot of people cant understand the time it takes to get a perfect finnish. i find it realy hard to half do a job, thats why i dont work in a crash shop now
quote]

I have quoted people $600 to get the bonnet to a rough finish, ie cut, welded, ground and rough panel finish, another $600 to primer finish. Left them speechless, they don't understand the amount of work involved.