Datsun 510 do-over

[510wizard]

Where is the cross bracing on your roof? I would imagine that your roof oil cans, when pushed on. The cross bracing also keeps the roof from vibrating,adds strength to the roof structure and the "b" pillar brace mounts the interior lite. If you could score the cross bracing from another car it wouldn't be hard to install, just four small welds per brace.

[jackedaw11]

Where is the cross bracing on your roof? I would imagine that your roof oil cans, when pushed on. The cross bracing also keeps the roof from vibrating,adds strength to the roof structure and the "b" pillar brace mounts the interior lite. If you could score the cross bracing from another car it wouldn't be hard to install, just four small welds per brace.

My car didn't have this piece when I got it, Icehouse already hooked me up with one. You have a very good point though, I should definitely remember to put the top-brace in before I start the bodywork.

[jackedaw11]

Days 5 and 6 - WOOOOOO!

So much progress! I know this is the easy part but its still insanely exciting to see so much get done. Over the past couple of days I've completely stripped out the car, and started work on my new crossmember. Engine, transmission, fuel lines, brake lines, and the front end are all out now. I'm just about ready to start sanding the paint off and getting some bodywork done.

removing the tail lights and the gas tank.


POSIN' HARD!


tail lights out, getting the gas tank out


Pulling out the engine! IT'S A BEAST!


my dime all emptied out and on dollies, it's crazy light, I can pick it up by the core support and roll it around by hand.


I had already flipped my crossmember, so the next steps are to cut off the old motor mounts, build some new ones, and build a mount for the rack and pinion.


I used a die grinder and a cut off wheel to trim the mounts off as close as possible to the crossmember, and then cleaned it up using a grinder.

[icehouse]

Hey buddy! Round 2 huh I feel like doing that on my SR car. Well all know putting them together is the fun part anyways

[sexyL]

Hey there, it's the guy that sold you the headliner bows.
How'd they clean up? The pics are small and can't really tell but they seem way better than they were before. Nice project going too.

[510wizard]

My car didn't have this piece when I got it, Icehouse already hooked me up with one. You have a very good point though, I should definitely remember to put the top-brace in before I start the bodywork.

Be sure to put some caulking, seam sealant or the like between the brace and the roof panel before welding the brace in place, to keep them from vibrating against each other. The factory used some stuff that dried out and turned into a rock after many years of the sun baking the roof, then the two would vibrate.

[jackedaw11]

Day 7 - TIG Welding FUN!

I'm pretty new to TIG welding; I'm not very good, but its FUN! I've been working on the motor mounts and the mounts for the rack and pinion. I'm using the old crossmember as a template. I wanted to redo the way I did the motor mounts so I started by using cardboard to make mockups. The holes for the sr20 mounts need to be approximately 19.5 inches apart, and about 5 inches above the bottom of the crossmember (don't take my word for it, my measurements may be off...). And the faces which the motor mounts will bolt to need to be at about a 45 degree angle.

My trusty little harbor freight tig welder, It works really really well and I added a foot pedal to it which makes it work even better!


Here's what I have so far:

I have the uprights done, and the mounting face welded together. The upright is about 2" tall, and the mounting face is about 2.5".




I also started messing around with the mounts for the rack and pinion. I'm using .12 wall 4130 tubing, and .125 thick 1018 for the flanges. I cut the tubing in half, and welded on flanges, which I'll use to bolt the two halves together. The tubing I used is 2.00" od and I think they're too big. I'm going to try this again with some smaller tubing, for a better fit.

My materials, the big black rod is a 2.5" chunk of delrin which I'll be using to make bushings.


the tubing cut in half, I used a bandsaw


clamped in place for welding:


Tacked:


Welded one side:


Flipped and welded the other side


Finished product:

[jackedaw11]

Day 8 - Machining Rack and Pinion Brackets

The title says day 8, but really this took several days of measuring, drawing, and machining. I had previously tried to make flanged brackets by welding tabs onto chromoly tubing. Ultimately there wasn't enough clearance under the transmission and this design didn't work. I needed to build a bracket that had a lower profile. I've completed work on the drivers side bracket, I started with a 1 inch thick piece of steel and machined it to fit over the head unit.

Here's the material, 1x3x7 cold rolled steel


The first step was to bore out a hole to fit the curved top of the rack's head (approx 1.9"). I used a boring head on my milling machine.


Next, I used the bandsaw to rough-cut the shape to fit down around the rack. I cleaned the dimensions up on the mill, which finished the inside shape of the bracket.


Now I started cutting the outside profile, again I roughed out the cuts on the bandsaw and then tuned the exact dimensions on the mill.


Here's the final shape of the bracket:


All that's left is to tap the holes, I took extra care to do this slowly. I had about 3 hours of machining into this piece so far, and I really didn't want to mess it up! Here's the bracket with the holes tapped, I also made the bottom clamp out of half inch steel.




And here's the finished product. I'm really happy with the way it turned out, it's a perfect fit, totally solid, and it'll have plenty of clearance under the engine.
Top shot


Bottom shot

[okayfine]

Very nice. There's a "machining" thread somewhere on the forum that could use an update with your pictures.

[cosmo1stgen]

Nice project. Im curious about the mods on your HF welder. Looks like it lays down a pretty nice weld. Do you have any info, plans or prints for the pedal adapter and the box on top?

[jackedaw11]

Nice project. Im curious about the mods on your HF welder. Looks like it lays down a pretty nice weld. Do you have any info, plans or prints for the pedal adapter and the box on top?

I'm not an electronics expert so I may be explaining this wrong, but here goes

The black box on top of the welder contains an op-amp used to filter the signal coming in from the pedal, it also has two pots that control the high and low limits for the pedal. You need this box because the wire running from the pedal acts like an antenna and picks up nasty RF interference caused by welding. There are also several places along the line where I've used capacitors to act as filters too. I built the box and pedal by following the schematic posted in this thread:

http://weldingweb.com/showthread.php?t=18117

[kayakdude07]

Mad fab skills! What kind of rack are you using?

[jackedaw11]

Day 9 - Lots of work, little to show.

I've been working over the past few days, and I only have one picture to show for it:



I've welded the rack brackets to the cross member. It was a lot of work to get it aligned just right. Vertically its perfectly on center with the mounts for the LCA. The centerline of the rack is about 3" from the back edge of the crossmember. According to the measurements I made, this should set it up for ideal ackerman.

I made the mounts out of 1.25" .012 wall square tube. The 1" square shanks of the mounting brackets slide inside perfectly, for now they are tack welded in place. I spent about 2 hours measuring and marking, and about 5 minutes doing actual welding.

I test fitted the crossmember under the engine and it seems to fit great, with plenty of clearance. Next I'll do a test fit in the car and then I'll finish weld everything.

[icehouse]

I keep waiting for my buddy to call..... I have the zx steering deals in my trunk.....

[S15DET]

When I made my rack mounts, I took pictures of the motor on a stand with the crossmember and rack bolted to the bottom of it. Have you done the same. You said that you have plenty of clearance so I'd like to see these just for comparison. I remember that I had to make a compromise from my ideal positioning because the rack tube was in interference with the upper oil pan, the larger aluminum one. I ended up doing a little grinding to make more room in places.
I guess the main cause of this was that when I made my motor mounts I lowered the motor a bit, but I also moved it rearward toward the firewall 40mm, so that should have helped.
If it's not too much trouble, try to send us a picture of the underside showing the pan and the rack. I even rested the motor and crossmember on a pair of saw horses to account for the compression of the rubber motor mounts.
Great work so far!!!