Opinions, Now COMPLETED! Lots of Pics!

[ng19delta]

Well, I received the "new" center-rear crossmember for my truck today(Thanks, Ed! aka Primal4x4) and I am trying to decide how to install it: My options are to trim the existing crossmember stubs, and welding the main section in place after cutting t to fit; OR, removing the rivets which hold it into the chassis(and also hold the front spring mountings in place) and then re-riveting it in place, which will require a hydraulic/pneumatic rivet squeezer(a tool I do not have, but may be able to rent somewhere) and an oxy-acytlene torch(to heat the rivets), again which I do not have.Potentially, I could replace the rivets with bolts, but would they be adequate?

I just had another concept hit me, and that is a hybrid installation where I trim both sections and fit it in, only having about 50% of the welding(if I find I can do it that way at all).

Anybody have any suggestions? I am hoping to do something this weekend...

Thanks!
Scott

[Gordon_M]

Got a similar situation with a transfer case crossmember which needs to go under my van.

I'n your situation I'd cut out all the rivets, do a full clean up of the 'new' crossmember, and just bolt it into place with buttonhead cap screws until you got your hands on a rivet squeezer. The end result will look so much better.

I also used them to mount the underslung rear crossmember which carries the bumperettes on the back of the van, as I need to be able to drop that off to get the fuel tank out ( it is a VERY neat fit )

I still hope to find a rivet squeezer before I have to install the transfer case though, but if I need to use the buttonheads for a year or so it won't bother me.

[WC4DOOR]

Funny, the more I get into this hobby, the more tools I end up buying. I went years without a torch, and now I can't go a day without it. The rivet gun is not needed, but is very fast and easy. If you heat the rivets with a torch you can peen the rivet with a hammer along with an other tool (a piece of round rod with a small concave divit milled into it) this will take at least two people. Bolts will work, but if you end up painting the frame you will burn any paint around the rivet holes. I also learned with this hobby, that if you rush a section of your project you will regret it. Find a torch, and buy or rent it. Order some rivets, there cheap. Get yourself a machine shop to mill you some small pieces of round bar to match your rivets heads. Then clean your new cross member. Get the old one out of there, and clean everything up. Put a couple of bolts in the holes, then install your rivets. We all get paint happy. Wait until it's done right to paint. You will regret it if paint goes on too early, then you have wasted your money on the paint, and your time to end up doing it again. I was where you are last summer, just be patient, and do things the right way. You will thank yourself in the long run.

James

[Bud Wheel]

The rivets are avail thru McMaster-Carr..... CHEAP
Snap-on has the rivet installer bits 4 sizes avail ( that fit into an air hammer aka air chisel )...... NOT CHEAP but reasonable
You can heat them one a at a time with a torch ( and replace the temporary bolts one at a time as previously posted )
The hard part is getting something behind the the rivet head so you can peen it over
There are several Huck Bolts in the frame , usually found at the blind hole locations.IIRC there are a couple at that cross member
Huck bolts and installation tools are avail from a few sources.... VERY VERY EXPENSIVE
Unless this is a "points" resto I would suggest using grade 8 cap screws and grade 8 nuts.

My opinion
John

[Phil P]

Hi Scott.

Using hot rivets and an air hammer is an ok route. The hydraulic squeeze is usually used in a factory enviroment because of noise not because it's the best. Rivets in ships and locomotive are air hammered up. Imagine the size of the anvil for a ships hull! Get the rivets to a straw colour and go for it. Before you start assemble it with some jigging bolts to hold it in alignment.

OR you could assemble it with fitted bolts. Thats where you get plain shank bolts bigger than the existing holes and then reamer the hole so that the bolt just goes in and is pulled home with the nut. This stops the frame from racking and moving in the bolt holes. Use high tensile bolts and torque them up. Bolting does mean you can paint in between without it burning off as in hot rivetting. If the rivets pull it really tight water can't get in. You could brighten the surfaces and paint with would stove paint. You won't go over the paint temperature beacuse the frame will absorb the heat from the rivets.

Phil

[ng19delta]

I do have a 4X rivet air hammer, but my largest set is 1/8", and that is just way small. I also don't have the proper shaped bucking bar. Will a 4X hammer work for 1/2" rivets? And what are the Snap-On numbers for the proper set & buck(or should I just make the buck as described in another post here)?

I am also considering separating the two pieces of the crossmember, because I noticed some corrosion between them starting to spread them along both front and back: Granted, I could probably simply POR-15 seal them but I think I would rather do it right, and disassemble the member, clean & straighten the flanges, and then seal it up before reassembly. This includes removing & replacing an additional 20 rivets or so!

Ideas?
Scott

[Phil P]

Hi Scott.

Sorry you'll need to split it and clean out the corrosion. The rust will keep building up and burst it apart.

The problem with manually hammering 1/2" rivets you can't do it fast enough. The frame 'chills' the rivets and they are harder to knock over. You also lose the contraction effect which is the bit that pulls it all together tight.

I would hire an airhammer. They are not that expensive to buy and you will have it for the next restoration. They do need a lot of air to run.

Phil

[Phil P]

Hi Scott.

I misread your post. You do have an air hammer. Buy the proper tooling. If you are not sure of the number go to the Snap On website and view their on line catalog.

Phil

[jbell]

Why can't I weld the crossmembers back to the the frame rails? Too much flex?...........Thanks, John

[ng19delta]

Hi Scott.

I misread your post. You do have an air hammer. Buy the proper tooling. If you are not sure of the number go to the Snap On website and view their on line catalog.

Phil

Snap On does not show one big enough for the task! May have to custom rig one...
Scott

[WC4DOOR]

McMaster Carr part #6104A44 or get the rivets setters with the gun 61044A45 $490.10. You have to make a new rivet setter tool for the 3/8. Very nice hammer.

James

[Phil P]

Hi John.

Welding tends to take the spring out of the frame. Rivetted chassis ride better. It's ok welding if you can gaurantee an homogenous weld. ie it becomes as one. Welding old metal on a frame unless you are working with a good bare frame that you can get in from all angles is fraught with danger. The heat from welding can cause stress cracking at a later date. It was rivetted for a reason. Welding is quicker and cheaper but wasn't used. There is always a danger of what appears to be a good weld is actually 'sympathetic adhesion'. It looks the part but is actually attaching very little to bugger all!! Rivetteing is best. Don't forget the ear defenders. My Grand Father was the Foreman over a boiler rivetting shop that built huge ships boilers. He would be described now as being 'Audibly impaired through exessive industrial noise'. A nice way of saying 'You're job has made you as deaf as a post!

Phil

[ng19delta]

Hi John.

Welding tends to take the spring out of the frame. Rivetted chassis ride better. It's ok welding if you can gaurantee an homogenous weld. ie it becomes as one. Welding old metal on a frame unless you are working with a good bare frame that you can get in from all angles is fraught with danger. The heat from welding can cause stress cracking at a later date. It was rivetted for a reason. Welding is quicker and cheaper but wasn't used. There is always a danger of what appears to be a good weld is actually 'sympathetic adhesion'. It looks the part but is actually attaching very little to bugger all!! Rivetteing is best. Don't forget the ear defenders. My Grand Father was the Foreman over a boiler rivetting shop that built huge ships boilers. He would be described now as being 'Audibly impaired through exessive industrial noise'. A nice way of saying 'You're job has made you as deaf as a post!

Phil

If I do it the way I am most likely thinking I will, I will be welding part, and riveting the rest: I am planning to cut the stubs back, and leave the spring mounts riveted in place, then cut the ends of the crossmember to match, & weld it onto the stubs. I still have to re-rivet the crossmember after I treat the rust: I may just use fitted bolts there for now, and then rivet it later, as I will still have access to the area after I finish the restoration...

Scott

[motto]

There is no easy way out of this one Scott and it sounds like you have probably come up with the best compromise by leaving the stubs riveted in place and welding the cut back replacement to them.
Another reason for doing it this way is that you cannot possibly get an intact crossmember into place in an otherwise complete chassis/frame, you would have to release the other cross members to spread the side rails enough. A nearby restorer here overcame that problem by cutting the crossmember in the middle and welding it back together in situ.
If you are going to weld to the stubs I would leave the lower plate off so as to weld the rest inside and out then instal the plate which could be riveted or bolted with a one sided weld to finish.
David

[ng19delta]

There is no easy way out of this one Scott and it sounds like you have probably come up with the best compromise by leaving the stubs riveted in place and welding the cut back replacement to them.
Another reason for doing it this way is that you cannot possibly get an intact crossmember into place in an otherwise complete chassis/frame, you would have to release the other cross members to spread the side rails enough. A nearby restorer here overcame that problem by cutting the crossmember in the middle and welding it back together in situ.
If you are going to weld to the stubs I would leave the lower plate off so as to weld the rest inside and out then instal the plate which could be riveted or bolted with a one sided weld to finish.
David

I like the idea of reinstalling in two pieces... I think that could happen much more easily as well- The hard part is, as you said, fitting it between two fixed frame rail: With the upper and lower pieces separate, I could jockey each into place with a little more authority... And the idea of being able to do a double butt-weld through the open space, as well as being able to more easily work a pair of fitted bolts into the two top holes on each side works well, too. Thanks for the ideas!

Scott