DIY arch extensions build
Posted: Tue Nov 12, 2013 10:35 am
Well as the Boss asked so nicley for a write up of how i do my archs, and i have some spare time, like lots 
here we go.
These pics are from my sammy ( Godzuki ) from a few years back.
I did these as there was a lot of rust around the usual places on the archs, well just the front but you cant just do 2 can you know lol.
I cut back to where the arch starts to bend back on itself, also on the inner arch i cut back the outer bend.
First thing is to do is decide how thick you want the steel you will using, i used 1.6mm standard body thickness steel plate, using 1.6mm you can form it in to the arch by hand as you go as it bends easy...ish. Although now i have done my mates in 2mm i would use that again next time, it doesnt bend so easy, but you can form it easy with a rubber mallet and a firm base, as once you have the template it will form itself.
Template is made from either hardboard or a similar kind of sheet, maybe GRP sheet etc. You will need to faff about though getting the correct curve you want as you make the template. more the arch you draw the more radius you get when you from the arch.
Template and arch ready for bending/forming
Dimension is 46 inch wide, point to point, and then 12inch high, this will give the 6inch extension.
You will need a 4x4 foot sheet to get all 4 archs done at the extension of about 6 inch from the body, bigger is always better as you can cut back to the size you want when fitted.
I dont have pics for how to fit them, but its easier with 2 people, one to hold it in place and one to tack weld it on. As i said before 1.6mm is ok to bend inpalce as you go by hand, i did this myself, yes a bit of F`ing and Ge`fing
2mm needs to be formed, once you have your `flat` arch you need to get a rubber mallet and a firm ground to hammer on. i used the floor as it is made from ash and compacts nice, a bag of sand could work or siliar, even a soil base aslong as there isnt stones in it as this may dint the steel slightly.
Work this way by the numbers, bit by bit, try not to do it all in one run across the arch.
you will end up with them like this
So once you have tacked in place, a dozen 1inch tacks will hold solid, and once you have plated underneath, even stronger. Dont seam weld as this will distort all the wing.
then fill and make good.
Godzuki was a sammy so had wider stance, also had fabboy rims and 33/10.50/15 tyres on with 32mm spacers.
Hope this helps a few guys who want cheap archs made, these cost me £15 inc metal, filler and primer. My ideas was to even make a GRP mould from the archs so if they ever get bashed to much its easy to pop rivet/screw new ones on, but that never came about.
These arch are stronger than you mite think aswell, i had it on its side and it rested on the front arch, just a crinkle and easy peend back straight.
Enjoy
wolly
here we go.These pics are from my sammy ( Godzuki ) from a few years back.
I did these as there was a lot of rust around the usual places on the archs, well just the front but you cant just do 2 can you know lol.
I cut back to where the arch starts to bend back on itself, also on the inner arch i cut back the outer bend.
First thing is to do is decide how thick you want the steel you will using, i used 1.6mm standard body thickness steel plate, using 1.6mm you can form it in to the arch by hand as you go as it bends easy...ish. Although now i have done my mates in 2mm i would use that again next time, it doesnt bend so easy, but you can form it easy with a rubber mallet and a firm base, as once you have the template it will form itself.
Template is made from either hardboard or a similar kind of sheet, maybe GRP sheet etc. You will need to faff about though getting the correct curve you want as you make the template. more the arch you draw the more radius you get when you from the arch.
Template and arch ready for bending/forming
Dimension is 46 inch wide, point to point, and then 12inch high, this will give the 6inch extension.
You will need a 4x4 foot sheet to get all 4 archs done at the extension of about 6 inch from the body, bigger is always better as you can cut back to the size you want when fitted.
I dont have pics for how to fit them, but its easier with 2 people, one to hold it in place and one to tack weld it on. As i said before 1.6mm is ok to bend inpalce as you go by hand, i did this myself, yes a bit of F`ing and Ge`fing
2mm needs to be formed, once you have your `flat` arch you need to get a rubber mallet and a firm ground to hammer on. i used the floor as it is made from ash and compacts nice, a bag of sand could work or siliar, even a soil base aslong as there isnt stones in it as this may dint the steel slightly.
Work this way by the numbers, bit by bit, try not to do it all in one run across the arch.
you will end up with them like this
So once you have tacked in place, a dozen 1inch tacks will hold solid, and once you have plated underneath, even stronger. Dont seam weld as this will distort all the wing.
then fill and make good.
Godzuki was a sammy so had wider stance, also had fabboy rims and 33/10.50/15 tyres on with 32mm spacers.
Hope this helps a few guys who want cheap archs made, these cost me £15 inc metal, filler and primer. My ideas was to even make a GRP mould from the archs so if they ever get bashed to much its easy to pop rivet/screw new ones on, but that never came about.
These arch are stronger than you mite think aswell, i had it on its side and it rested on the front arch, just a crinkle and easy peend back straight.
Enjoy
wolly
Might actually give this a go with my LWB.