Today, I got the frame and bottom of the tub painted. Before I mated them together I noticed that a few of my spot welds along the side and back had broken loose. So I spent a little while re doing them.
Notice the new welds along the right and back sides.
When my wife got home I enlisted her help in “marrying” the frame to the tub. It isn’t all that heavy (probably around 60-75#), it’s just too awkward to do it without scratching up the newly painted tub bottom. Once the frame and tub were married, I got to work making sure the frame was lined up correctly and then started welding.
I only welded up the outside and corners today. My welding skills aren’t that great, so they required grinding also. There are quite a few welds on the outside, and a LOT of welds on the inside and crossmembers! That will have to wait until tomorrow or the next time I’m off.
Today I got the frame sanded down and primed on both sides.
I primed the rear crossmember.
And the bottom of the tub.
Lastly, I permanently bolted (had to cut about 3/8″ off the carriage bolts) and welded the rear crossmember to the frame and touched up the primer.
So hopefully tomorrow I can get a couple of coats of OD on the bottom of the tub and frame. If it dries fast enough I’ll fit them together and stitch weld them together. I also need to extend the front angle up by about 1/4″ so that it is the same height as the seam of the patch panel. That way I wont have to do any metal finishing on that seam (on the outside anyway).
I took my old crossmember to the fab shop this morning – they said “no problem, check back after lunch”. I got him to bend 3 pieces x 43″ long. I called back after lunch – $50! – but they were ready. Once I got back home, I discovered that they used a little thicker steel, so the height of the channel was about 1/8″ taller – not really a problem, so I can work with that. He went ahead and used the full width of the sheet – 49″ also.
I began by measuring the length of the end tab and marking it with a square.
Next, I cut the tab out on both sides.
Then bent the tab down.
Lastly, I measured the total length of the crossmember, marked that with a square, and added 1 7/8″ for the tab – then cut to length. I repeated the process to create the other end tab.
I test fit it in place.
Then marked and drilled pilot holes for all of the various holes.
I came back and used various size bits to re create the original holes. I used a step drill bit to drill the 1″ hole on the drain plug side and 7/8″ hole on the other side.
I test fit it in place and realized that I didn’t cut the half moon out that goes around the drain plug hole. So I used my spare chassis to locate that so that I could re create it on the new crossmember (is was rusted away on the old crossmember).
Lastly, I test fit it in place one more time and drilled the holes where the rivets originally were. I WAS just going to put bolts back in their place, but ran across some carriage bolts while looking through my bolt bin. I think they look pretty close to rivets, and definitely better than bolt heads!
Tomorrow, the plan is to prime and paint the bottom of the tub (after I grind down those spot welds) and crossmember. Maybe if the paint dries fast enough I can get the frame welded back on the tub.
I finally got around to working on the M100 again yesterday. I decided (in my mind) to use the frame off of my other M100 chassis because of how much rust was on this one. After checking out the other frame, it wasn’t worth the extra trouble – the other one was only slightly better. The rear crossmember wasn’t rusted away on it.
So…. I dragged the original frame out of the scrap pile and inspected it again. The rear crossmember needed replacing for sure. About a 1/4″ of the edges of the 2 middle crossmembers were rusted away – which I ground down when I was working on it before. So, I decided to go with it – I was going to replace the rear crossmember and leave the middle ones. I started removing the rear one.
If you’ve never looked at how the frames are assembled, they used 3/8″ rivets AND welding. The rear crossmember uses BOTH methods. There is a rivet on the bottom of each side and the edges are welded on the end and the bottom. I used the plasma cutter to cut the welds so that I could remove the crossmember so that I could get in there with my side grinder to grind down the bottom of the rivets and the rest of the welds that weren’t cut off. Once they were ground down, I was able to use my air chisel to drive out the top half of the rivets.
Then I set the frame on the tub for the first fitting:
It fit pretty good! There are a couple of spot welds that need to be ground down a little more for it to fit flush to the tub though. Overall, it fits well. It should fit right back in the original location. I WILL have to do a little more fitting on the front angle, as it is TOO far away from the new metal that I welded in. I don’t know what is going on there yet.
I think today I am going to scuff the bottom of the tub down (after I grind those spot welds and make sure the frame fits flush) and spray some OD on it. I might go ahead and spray the frame with primer (maybe the bottom of the tub too) and paint it too.
There is a metal fab business a few miles away that I am going to go ask if they will bend a channel for me. If so, I’ll get a FEW4′ pieces bent. The rear crossmember measures 37.5″ inside of the outside frame rails. I am guessing that the pieces of channel need to be 42″ long so I will have enough material to cut and bend the tabs on the ends. By the way, the metal is 12ga.
Here are a couple of pics of the rear crossmember after I cut it off. You can see how bad it was rusted.