Frame stretch - split frame channels? Ideas? (2 Viewers)

[DirtSniffer]

Getting ready to re-do my 40 frame stretch and shorten it up. Would it be a bad idea to remove all of the frame rivets and split the inner and outer C channels, weld up the outer channels for the stretch, then weld up the inner channel off the frame and re-install with 3/8 bolts in place of the rivets? Or will the bolts simply loosen up from frame flex? I would probably get button head bolts for the bottom so they don't get as beat up as hex bolts.

I ask because I feel it would be easier to keep things straight doing the outer first. And allow me to clean up hard to reach rust. And maybe add/replace some welded nuts on the inside of the frame. I would keep the stretched frame piece in-line with the factory angle and simply let the frame widen a little extra. I will be running wider axles and links so the factory mounts do not matter to me. I will also probably be making a new rear bumper as well.

Even though I've seen it done multiple times, I would like to avoid a vertical cut like I originally did while keeping the added frame rails parallel. Keeping the factory angle will make having an angled cut much easier.

I am also concidering this method:

 

[PIP]

I have not worked on a 40 frame, but I've done a lot of frame repairs and stretching for 1 ton 4x4 work trucks through class 8 semi's. I look at rivets more like welds than bolts.

Taking a frame apart is one thing. Getting it back together can be an entirely different thing. If it has serious corrosion then maybe it's necessary. If it's an old frame in decent shape it may be way more trouble than it's worth to take it apart.

I prefer angled frame cuts. Overlapping or with a backer. I've done some stuff where angled cuts weren't an option and twice, in a pinch I just straight up butt welded a frame back together with good prep. I've never had a steel frame repair/modification fail or crack. And I know most were beat hard in logging use. I don't recommend weld repairing aluminum frames. One of those kicked my butt.

Think it through, lay some nice beads and while it's still red hot hit the welds and HAZ with a powerful needle scaler to reduce surface stresses.

Good luck!

 

[DirtSniffer]

I have not worked on a 40 frame, but I've done a lot of frame repairs and stretching for 1 ton 4x4 work trucks through class 8 semi's. I look at rivets more like welds than bolts.

Taking a frame apart is one thing. Getting it back together can be an entirely different thing. If it has serious corrosion then maybe it's necessary. If it's an old frame in decent shape it may be way more trouble than it's worth to take it apart.

I prefer angled frame cuts. Overlapping or with a backer. I've done some stuff where angled cuts weren't an option and twice, in a pinch I just straight up butt welded a frame back together with good prep. I've never had a steel frame repair/modification fail or crack. And I know most were beat hard in logging use. I don't recommend weld repairing aluminum frames. One of those kicked my butt.

Think it through, lay some nice beads and while it's still red hot hit the welds and HAZ with a powerful needle scaler to reduce surface stresses.

Good luck!

The frame in working on is pretty good shape, but I'm sure there's some minor rust sandwiched between the frame channels. Thinking back to all the other rivets I removed on my other frame, I probably want to avoid doing that again. Will for sure be getting plated.

I haven't heard of that needle scaler trick, I will keep that in mind thanks

 

[PIP]

Amazon product ASIN B000Z9B9WY
Something like one of these works good.

 

[DirtSniffer]

Amazon product ASIN B000Z9B9WY
Something like one of these works good.

I have one, but about due for a new one with all the rust we deal with around here

 

[Mike Shull]

I removed my inner frame since it was thinner metal and I replaced it with a boxed c-channel that was about 4” longer on either side. I cut my outer frame at an angle, drilled 1.5” holes, slid the boxed c-channel inside, plug welded it to the outer frame and fully welded to the inside of the frame. I finished this off with scab plates on the outside of the frame to cover the diagonal cuts.

This is way overkill. Here is a link to pictures.

Post in thread 'Stretched 1-Ton FJ40'
Builds - Stretched 1-Ton FJ40 - https://forum.ih8mud.com/threads/stretched-1-ton-fj40.1253008/post-14093080

 

[Mike Shull]

I never showed this picture with the frame extension part of my thread. This shows the scab plates. I also plug welded these.

 

[DirtSniffer]

I never showed this picture with the frame extension part of my thread. This shows the scab plates. I also plug welded these. View attachment 3347910

Thanks for the ideas, I hadn't gotten to that point in your build yet. Got some thinking to do...

 

[Mike Shull]

Thanks for the ideas, I hadn't gotten to that point in your build yet. Got some thinking to do...

I was trying to show you the outer part of my frame extension. I don’t have many pictures of that area.

I like my rear frame notch and coilover mount though I’m not sure that I would replicate how I braced the backside of the frame again. I’d make a better inner c-channel that is one piece and bent to fit the contour of the tower. I believe it’s still strong the way it is but I did this with two channels on either side and scab plates. My brake won’t bend a large enough piece to make this in one shot. One thing at a time.

 

[White Stripe]

Getting ready to re-do my 40 frame stretch and shorten it up. Would it be a bad idea to remove all of the frame rivets and split the inner and outer C channels, weld up the outer channels for the stretch, then weld up the inner channel off the frame and re-install with 3/8 bolts in place of the rivets? Or will the bolts simply loosen up from frame flex? I would probably get button head bolts for the bottom so they don't get as beat up as hex bolts.

I ask because I feel it would be easier to keep things straight doing the outer first. And allow me to clean up hard to reach rust. And maybe add/replace some welded nuts on the inside of the frame. I would keep the stretched frame piece in-line with the factory angle and simply let the frame widen a little extra. I will be running wider axles and links so the factory mounts do not matter to me. I will also probably be making a new rear bumper as well.

Even though I've seen it done multiple times, I would like to avoid a vertical cut like I originally did while keeping the added frame rails parallel. Keeping the factory angle will make having an angled cut much easier.

I am also concidering this method:

View attachment 3347728

View attachment 3347730

View attachment 3347731

View attachment 3347729

I would do as you said in your first paragraph and stretch each C individually then bolt it together with hex bolts.

 

[47coeman]

I removed my inner frame since it was thinner metal and I replaced it with a boxed c-channel that was about 4” longer on either side. I cut my outer frame at an angle, drilled 1.5” holes, slid the boxed c-channel inside, plug welded it to the outer frame and fully welded to the inside of the frame. I finished this off with scab plates on the outside of the frame to cover the diagonal cuts.

This is way overkill. Here is a link to pictures.

Post in thread 'Stretched 1-Ton FJ40'
Builds - Stretched 1-Ton FJ40 - https://forum.ih8mud.com/threads/stretched-1-ton-fj40.1253008/post-14093080

Ya way over kill but i bet you never cracked a frame that way. i did it the same way on my fake 45 extension with 2 55 frames and 120 WB it turned out good also.

 

[DirtSniffer]

Some useful information on the frame rivets here.

I am still tempted to remove all the rivets as I was originally thinking because I hate myself. These lock washers were mentioned in that thread and may alleviate my fears of loosening bolts along with welding the nuts on the inside.

 

[GLTHFJ60]

Nord-locks. Those seem to be the best.

I would hesitate to replace rivets with bolts, as long as the bolt section width is at least as wide as the rivet. Meaning drill out the 3/8" rivet or whatever to a 1/2" bolt or larger.