Frame Bending

[DieselSub]

I'm building a trailer out of an '82 C20 (3/4 ton pickup if you have to ask ). Everything forward of the bed is gone except about 3 1/2 feet of frame. Now I just need to bend the frame rails in and weld on a coupler...

I've read a number of conflicting articles about modifying frames and wanted to get some more opinions.

1) Heating the frame will make bending it easier. But will it also damage the frame? Some articles say to "never heat the frame", while others say bending it is OK with a little heat. I know that practically everyone welds their frames, but I'd like to hear any theory that people know about best practices for keeping metals strong.

2) I'm going to cut a v shaped notch at the top and bottom of the frame rails to allow them to bend inwards. Should I simply weld this closed, or weld a larger plate (say and extra 1" of .25" plate in either direction) over the resulting slot, or maybe bolt a heavy plate to repair the top and bottom of the frame rails?

3) I bought a weld-on A-frame coupler. Like the instructions say, can I just weld it to the frame, or should I use some grade-8 bolts to hold everything together?

Yes, yes, yes, I'm probably being overly cautious. I'd just like to hear what others do to beat their frames into the correct shapes

 

[tRustyK5]

Once you notch the upper and lower flanges you won't need heat to bend the rails inward. i would fishplate the upper and lower flanges after the notches have been welded up and ground smooth. About 4" on either side of the welded area should do just fine.

These frames are plain mild steel. For the coupler I'd bolt it and then put a few stitch welds on it. Should be just fine. This is just a utility trailer right?

Rene

 

[diesel4me]

I have one in the yard!

I have one made from a 1962 GMC 3/4 ton 2wd frame with a later bed (74) on it,for storage mostly--mine had the coil spring suspension with the trailing arms that always rust away,mine are pachted with angle iron,I would not use a coil sring setup again--it bounces like a basketball behind you down the road and it sways all over,the other ones I made with leaf springs worked fine,they all sucked to back up though,due to the tounge being kinda short,its real easy to jacknife it backing up..

Like tRusty said,all I did was cut a "V" notch in the top and bottom of the frame rails,and I used a large pipe wrench and a cheater pipe on its handle to bend the rails in,I did heat them up some,but my dinky torches hardly even got the meatal red--they bent easier than I thought!--I just butt welded the frame back together and put a 1/4 inch x 1-1/2 inch peice of flat stock over the welds(after grinding them smooth) and welded them over the "v" splice..my coupler is just welded on,but you can bolt it and weld it for extra peace of mind...I would not be too concerned about the strength of the frame,you likely wont load it as heavily as you would if it still were a pickup truck,and the frames are very strong--the frame in my 74 K20 is pretty rotted and thin,and I've hauled 4000 lbs on it many times and plowed heavy wet snow with it,hitting snowbanks at 20+mph to move wet cement snow,and its still in one peice!!--

-In fact,I was seriously considering cutting the truck up and making it into a trailer,so I can use the flatbed and crane for scrapping metal again--it lost reverse in the th350 tranny,and has too many other problems to be roadworthy again--but the sad shape the frame is in discourages me from doing it-that and the fact its buried under a 5ft drift next to my garage...

 

[86chevybanshee]

i was camping up in maine once, i was buzzing around on my quad and stumbled apon a trailer made from an old chevy truck, not sure what year it was but it had a 14bsf in it with those rims that have a ring around them that if they pop off will kill you.

well the trailer was full of wood so i hooked it up to my quad and brought it to tthe camp site, burnt all the wood and stripped it for the axle and 56" rear springs.

it looks like the guy who made it cut off right behind the cab and just bent it and put on the hitch part and made a wooden bed.

it was a preety cool thing

 

[sweetk30]

i was camping up in maine once, i was buzzing around on my quad and stumbled apon a trailer made from an old chevy truck, not sure what year it was but it had a 14bsf in it with those rims that have a ring around them that if they pop off will kill you.

well the trailer was full of wood so i hooked it up to my quad and brought it to tthe camp site, burnt all the wood and stripped it for the axle and 56" rear springs.

it looks like the guy who made it cut off right behind the cab and just bent it and put on the hitch part and made a wooden bed.

it was a preety cool thing

hay man that was my trailer!!!!

 

[divorced]

I don't cut a v-groove in mine. I just make a straight cut on the top and bottom rails and bend one up a bit and the other down a bit and then bend the framerails together so the pieces overlap, and then weld. For the hitch I weld the coupler to a 2" or 2 1/2" (depending on what coupler I buy) piece of box and then cut a square out of the front top on the tongue where the framerails come together and put the box through there. It extends back to a piece of angle welded between the rails. I can take a picture of how I did mine, but it may take a day or two. It sucks you don't live closer, I plan to scrap mine.

 

[86chevybanshee]

hay man that was my trailer!!!!

oops

 

[75-K5]

I don't cut a v-groove in mine. I just make a straight cut on the top and bottom rails and bend one up a bit and the other down a bit and then bend the framerails together so the pieces overlap, and then weld. For the hitch I weld the coupler to a 2" or 2 1/2" (depending on what coupler I buy) piece of box and then cut a square out of the front top on the tongue where the framerails come together and put the box through there. It extends back to a piece of angle welded between the rails. I can take a picture of how I did mine, but it may take a day or two. It sucks you don't live closer, I plan to scrap mine.

If you're going to scrap it, please let me know before you do it. If it's in useable shape I might want it.