Boxing a frame, questions?

[ccm399]

Hey David,

While I have never boxed a frame on a Syclone personally I have a fair amount of chassis fab time under my belt. If it were me I would get as much of the weight off the frame as possible before I began, especially if just lifting the trunk on a lift tweaks the chassis that much. From there I would get material at least as thick as the current frame but if it were me I would use 1/8 to probably 3/16 max. As for the size I would cut the pieces the same size as the inside dimension of the current rails. I would not weld them inside at all though, I would line them up and tack them in place so there is a corner to fill some thing like:
W _____________
W _____________ - Original Frame Material
| |
| |
| |
^ Boxing Material



Weld where the W's are.

You will need to check your welders specs (if it is a multi voltage machine make sure you look at the 110 ratings) but I would think you should be ok. Go slow and MOST importantly make sure the metal is CLEAN!!! Use a wire wheel and a sanding wheel in a grinder to the the rust/paint of the rails. Also, do not run a long continuous bead of weld, you will distort the material and start and then your chassis will not be as square as you would like! Move around weld a couple inches at a time max. If you have all your pieces cut before welding you will have plenty of places to jump around to without creating too much heat build up. If you need to you can always take a break part way through to allow the material to cool. Actually depending on the welder model you might HAVE to take a break because of it's duty cycle.... but that's another topic all togehter. Speaking of square I would do some measuring before welding to make sure I am not boxing a twist or bend INTO the frame.

Hope this helps,

Chris

[Syclone892]

Hi Chris

Thanks for the response you have given me some ideas I needed and some new questions to ask

When you say take as much weight off the frame are you talking just a weight reduction in general? If thats the case then its about as far as I would get for a street vehicle. I think the main reason for the flex compared to a car is that the cab and box are not connected which creates a stress point on the frame compared to a car where its all one piece ya know.

I have heard the frame is roughly 1/4 thick, if that is the case would you still recommend 3/16 max size for the plate? I don't have easy access to the truck currently to measure the thickness.

I do understand how to fit the plate and were to weld it, I see where that would be better than slightly inside the frame.
As for the welder I believe its a miller autoset 211 not sure if you know much about it or could give some advice if that wouldn't be good enough using 110v.

I hear ya on cleaning for a good weld also, I do a bunch of welding at work but nothing structural mainly just brackets for strobe lights etc. I plan on making all the pieces then welding it all together. Since the truck is at my brothers house an hr away it will be easy to only weld so much and then let it cool and come back to it the next week.
How would you recommend I check the frame for straightness? I know there are certain alignment holes in frames for frame machines but I'm just wondering how close I could measure those to see if its square. That it one reason I would have the tires resting on blocks so it simulates the normal load on the frame also but the bed will be removed to gain proper access to weld the frame.

If you don't think that welder would be enough with the 110v I may have to just tack everything up like that then trailer the truck to work were I could use our big welder with 220v I believe that one is a panasonic gunslinger 260.
Oh also what size wire would you recommend for this? I believe we have the .035 size but am not 100% sure.

I have tackled quite a few projects thats the main reason I am contemplating tackling this one plus the added benefit of being the one to do the work to my own vehicle always feels good!

Thanks for the help I appreciate it greatly

[Syclone892]

I had another question I just thought of, whats your thoughts on adding some sort of x-brace and do you think it would need to be the same height as the frame or would smaller with some brackets on the ends to tie it to the frame be good? I most likely would have to redo the exhaust for something like that but was just curious. I do currently have a nice crossmember/ driveshaft loop that replaced on old crossmember that was very flimsy so maybe I would hold off on an x-brace.