Slow Car Fast
THE MG
January 14, 2009 - In order to fit the new frame rail to the bottom of the car, it has to be cut to match the contours of the floorpan.
There are enough little dips and lips to make this a real pain in the butt, actually. Lots of careful measuring and turning parts around in my head, then it was time to cut.
entry 140 - tags: suspension, frame
January 14, 2009 - All that careful measuring, and I cut with a Sawzall.
Actually, it's possible to be pretty accurate with one. Check out how straight that edge is! I can't do that well with a bandsaw.
entry 141 - tags: suspension, frame
January 14, 2009 - Before I could attach anything, I had to clean off the frame rails.
That's some good looking metal for a 37-year-old British car! I used a wire wheel on my angle grinder to clean it up. Really, I don't need to clean up the side of the original frame rail as I can't weld to there, only the edge.
entry 142 - tags: suspension, rust, frame
January 14, 2009 - After innumerable test fits, small tweaks and a wholesale chop of a 3/4" strip down one side, the suspension is ready to weld in.
Note how the upright goes right into the front fender. It lines up nicely with the support behind the fender. So that's good!
You can see the angle level I'm using to make sure everything is correct. After all that test fitting, I still ended up with a surprising gap between the top of the rail and the floorboard. I'll fix that either with a piece of small angle welded in (which will actually provide a little more stiffness, I think) or by persuading the thin floor to move slightly. It's not far off, but it doesn't take much for a weld to be a problem. I'm also probably going to have to see if I can remove the asphalt sound deadening from the floorboards. Now that is going to be a pain.
Everything's just welded enough to hold it in place, although I can't call some of those welds under the car tack welds. They're pretty beefy. The ones at the top of the upright are tacks, though.
entry 143 - tags: suspension, frame
January 14, 2009 - So, how did the wheel align after all that?
Almost perfectly. It looks like it's moved forward slightly from my ideal, but not enough that anyone will ever notice. The only problem is that according to my angle level, I don't have much negative camber. I think I'll move the top of my upright inboard just slightly, enough to move the adjustment range more into the negative range. Before doing that, though, I'm going to measure it again tomorrow. I should tighten all the suspension bolts more first to make sure I'm getting accurate readings, they're all just finger tight right now.
The suspension has lots of room to move and it's all nicely fixed to the car. Some extra braces will be coming to reinforce the upright, but this is enough to get me started.
Now I just do the same (only faster!) on the other side of the car, then put the crossmembers in. And with that, I can start to figure motor mounts, steering column routing, wheel flares and a bunch of other items. Here we go!
entry 144 - tags: suspension, frame
January 16, 2009 - Yuk.
I'm removing the asphalt sound deadening from the floorboards so I don't set it on fire while welding to the floor. It's coming off fairly well with a hammer and chisel, so I'm going to pick up an air hammer on the way home from work today to expedite matters. Then the condition of the floorboards will be revealed, but nothing I've seen so far leads me to be concerned. It looks bad in pictures, but all the rust is just surface scum. I can't believe I got so lucky!
entry 145 - tags: interior, rust
January 17, 2009 - I've been given varying advice on how best to remove the asphalt.
Freeze it with dry ice so it shatters, warm it with a heat gun and use a putty knife, and melt it off with various chemical cocktails. I stuck by my original plan and picked up a $4.50 air hammer from Harbor Freight. It was the perfect tool for the job, ripping out the stuff in no time flat. This picture was taken partway through the work.
entry 146 - tags: floor, sound deadening, tools
January 17, 2009 - Unfortunately, the car was not completely rust-free.
Even before all of the asphalt was up, this section came to light. There's a hole in the top of the sill as well as this damage to the floorboard at the base of the sill. Not too much, though, and it's restricted to the area that can be seen here. It's an easy patch job, no need to bother with new panels. I'll probably cut out the floor between the sill and the raised bit, then put an L-shaped piece of steel in to tie them together.
With the rest of the floors cleaned off on both sides of the car, this was it for rust. Everything else looked just fine. There's still asphalt on the raised ribs on the floor in this picture though, and that makes it look a little dodgy.
entry 147 - tags: rust, floors, asphalt
January 18, 2009 - It was too nice a day outside to work much on the MG.
But I did get the left front suspension started. Here it is in the highly professional jig for the upper control arm placement.
I assure you, the welds look much less dodgy in person!
entry 148 - tags: suspension
January 19, 2009 - See?
Not so bad.
entry 149 - tags: suspension
January 19, 2009 - The left front suspension is all together.
So tomorrow it'll get welded to the car. Then the steering rack support - and then I'll be able to steer the wheels! How exciting.
entry 150 - tags: suspension
January 20, 2009 - Whoops.
I got the second frame rail cut to shape and tack-welded into place. Then, just to check my placement, I checked the horizontal distance between the front control arm mounting points.
They were about 10mm too wide.
That's odd, how could I have made that miscalculation? Just for fun, I checked the distance between the rails at the front. Again, about 10mm too wide. But the rails were pushed up tight against the inside of the stock rails, so how could that have happened? A bit of head scratching and then I checked the width of the rails at the firewall. Perfect.
They're splayed.
So I crawled back under the car again to see if one wasn't butted tight against the stock rail, but both were good. Sighting along the new rail showed me the problem, though. The rails weren't straight. In my excitement to put the suspension pickups in place, I'd managed to warp them. Obvious in retrospect, not something I expected at the time. At least it appears I did it nice and evenly, but this isn't good.
So I think I'll try heating up the inside edge of the rails and see if they pull back straight. It's a trick I learned from an exhaust shop - heat up the steel and let it cool, and the hot side will shrink down a bit. Basically, do the same thing that bent them in the first place. Either that or I cut them loose and start over, or cut and weld the rails with an angle correction. Ugh. I'll try heat first.
entry 151 - tags: suspension, frame, ok
January 21, 2009 - Some more thinking on the frame rails.
I'm going to replace them, and I'll take the opportunity to bump the wall thickness a bit. Just because. The mounts will get cut off the existing rails and welded on. I know how I can do this without needing to go through all the fixturing again.
This is the smart choice. I was trying to think of easier ways, but it'll only be another couple of hours worth of work, and it's the strongest and best solution.
entry 152 - tags: suspension, frame
January 26, 2009 - After a fairly short and noisy period, the frame rails were removed from the car.
I then proceeded to chop them up and remove the brackets. Voila, ready to weld on to the next rails. Slowly, without too much concentrated heat. The only thing I have to worry about is getting the brackets the correct distance apart, and for that I'll simply weld them in with a lower control arm in place.
In other news, I took the Camaro in to work today. Everyone was surprised, as they assumed it had been gutted some time ago. Far from it - they're much more compact when fully assembled! I'll order a coolant temperature sensor tomorrow so I can make sure the temperature problem is sorted out before the engine goes in the new car. And I also noticed the big black car has cruise control. Hmm, how could I integrate that while making it appear completely vintage? That could be a pretty cool addition...
entry 153 - tags: camaro, suspension, frame
January 28, 2009 - I picked up some more steel for the frame rails.
This new stuff has a thicker, 11ga wall and is hopefully straight. Step 1 was to weld on the front control arm mounting point, then I bolted up a control arm and used that to fixture the rear. Quick and easy. The relationship between the lower and upper control arms is handled by the fact that the front mounting point remained fixed to the upper one.
entry 154 - tags: suspension, frame
January 28, 2009 - To minimize the chances of warping, I moved around the pieces to weld them.
The idea was to never let one area get too hot. The thicker wall also helps here.
entry 155 - tags: suspension, frame
January 28, 2009 - With the frame rails assembled, I cut them to shape to fit the floorpan, then tacked them into place.
They went in quite satisfactorily and with the angles all looking good. Then, to make sure, I stuck the steering rack crossmember in place after cutting it from a calculated (not measured) length. And it fit perfectly. Everything looks to be centered and the dial level is happy. So we're good! That didn't happen right away, I had to play around with it all for a bit until it all just clicked into place. Sharp eyes will notice that I did have to cut a slot in the frame rails and weld it up, using that to take out a small bit of warp from the welding. It's minor, but spread over a 4' length even half a degree could be problematic. But it's all good now!
I just need to fully weld the frame rails on, then I'll come up with some steering rack mounts. Then, once I know where the steering shaft will run, I can start reinforcing and integrating the new frame into the unibody. I'll also start massaging the transmission tunnel to fit the (huge) T56 transmission.
I feel as if I just unlocked the potential for a large percentage of the project to move ahead.
entry 156 - tags: suspension, frame
January 28, 2009 - The next step is the steering rack mounts.
To behind, a fair bit of careful measurement. I want to try to minimize bumpsteer, and the best way to do that is to start with the factory Mazda location and then work from there once the suspension is assembled. I duplicated the factory brackets using a piece of 1x3 rectangular steel. A plate on the bottom will provide some lateral strength.
entry 157 - tags: steering, frame
January 28, 2009 - That 1x3 steel (actually, I think it's 1x2 when I think about it) I used for the steering rack mounts is not new steel.
Far from it - I have some very heavily overbuilt railings that were pulled out of a building under renovation. They live out in the backyard and I chop off a bit when I need it. A bit of quality time under the wire wheel on the grinder and it looks new and ready to weld.
entry 158 - tags: tips
February 1, 2009 - Time to mount the steering rack, umm, mounts.
I'm still just tacking everything in place, but it's almost time to commit. I did chop a bit of extra frame rail off the sides to clear the rack itself, this was always part of the plan - I figured it was much easier to make them shorter than longer.
entry 159 - tags: steering, frame