Best line for adding SC flares

[Shaun @ Tru6]

I'm butt-welding SC flares onto my 73 this weekend. Flares were cut pretty large, especially toward the rear.

Given all the compound curves in this area, is there a "best" arch to weld these on that I could cut down to?

[mattmcginn]

They're going to have a natural line where they want to "meet" the existing fender as "they're all the same" above a certain altitude and longitude.

Here is a rough out of an SC In installed turbo flares on (from Pelican, naturally) to get an idea, adding SC's to an early car, if given just the flare, is roughly the same thing process wise, if not location wise. They're butt welded, ground both sides, etc.



Ideally you'd get less warpage if you could get it all to meet on a convex zone, but you can't do that, especially at the 11-1:00 zone, its very flat there with little tension in the panel, for a good distance on both sides of the weld, especially when doing a turbo flare that just heads straight for the horizon instead of tapering off toward earth.



The benefit is that you can get at that spot top and bottom to hammer and dolly out any warpage really easily. You can also easily clamp heat sinks and flat copper backers behind it to prevent warpage in the first place.

A hard spot to get to the existing car and added flare to hit flat, and also to work out warps is the flat-but-vertical zone behind the door gap.

If the flares are not cut off the car yet, what it is good to do is to have them give you the lockpost too-and you can split the quarter panel from the lockpost and fit the panel to give you the SC flare from the rear bumper across the top but then straight from 12:00 to the lockpost (assuming passenger side) Then you position and run your butt weld into the lockpost area, and then do 10 or so plug welds instead of 18" of tedious fitting and butt welding all the way down past the torsion bar hole into the lower rocker. You'd still have to violate the quarter/rocker seam at that joint, but if you're really chopping into the car for other reasons, (jack point replacement, rocker replacement) you should be able to prime/treat the back of the weld well to prevent corrosion.

Hope this helps!

[Shaun @ Tru6]

THank you Matt, helps a lot. In fact it's your technique you outlined here some time ago that I'm using to get these on. Excellent write-up! THough I wish I could have you come up to Boston to stitch these on.

Here are my flares. they are actually cut on the small side forward but should work. I plan on going very slowly to keep warping to a minimum. Was going to start today and get them both tacked on but I seem to have loaned out my grinder...nowhere to be found.

Questions: should I be hammer and dollying each spot weld as I go? Do you start at 12 o'clock and then go to 9 and 3 and then keep halving each distance? Or start at the rear taillight and go back every 6 inches?

Will post progress. Thanks again for your help.

flares

[Shaun @ Tru6]

Little bit of practice today. If I take my time, I could see doing this in 2 days with good results.

Hobart 140, heat setting at 2, wire speed at 30, .023 wire.

I ground the weld down with a cutting wheel on the grinder. Getting more penetration than I think I should, weld bead came through the other side. To the left, you can see the seam. Just a straight cut-out of a section of old quarter clamped back in place.

[arrivederci]

Looks good. I'm doing the same this weekend on my '72 -- still deciding between butt weld and lap.

[Shaun @ Tru6]

Josh, click here and go to post 19.

Butt welding flares vs. lap welding

Butt looks like the way to go.

[78SCRSMAN]

+1 on the butt
I have the same welder (very nice) and use heat 1 @ speed 35... the first weld looks a tad clumpy but once hot is just about right. I use the start and stop (bursts) method. Warping will be the problem in that area.
Also, if your cut isn't perfect (like most of mine) and you get some slight overlap in spots, I found using a dremel with a cutoff disc works great to cut it back a bit once the panel is tacked in place.

I'm looking forward to see how it turns out.

[Shaun @ Tru6]

I hear what you are saying and will try 1 as well. I can say that the weld is very strong...as strong as the original metal.

One reason why clumpy is I loaned out my nice welding helmet and am borrowing a friend's "cheap" auto-darkening. It does make a difference.

Here's the backside. Getting too much penetration?

[78SCRSMAN]

I'm not a welding expert by any means but I would clean/grind to bare metal the seam on the back side as well. I think you will find it will look much better because it will flow better. I'm not sure too much penatration is as much an issue as too much heat, which can cause warping. My guess is that you will experience some warping no matter what you do but the nice thing about a mig is the heat is confined to a small area. So warping will occur locally, which can be fixed with body filler. You'll need to use some anyway.

I'm sure there are techniques to minimize warping, I just don't know what they are... hopefully someone will chime in. One thing you could try is to grind flat your initial tack welds. I experienced the majority of my warpage probably because there was excess metal there and so it stayed hot there longer... if that makes any sense.

[Zeke]

Yep, that makes sense. Grinding down high tack welds does allow you to climb onto them when you're welding between tacks.

Shaun, it is not necessary to hammer MIG welds. They are too hard anyway. Gas welds are softer and will respond to hammering, but this work hardens them to an extent.

[944jcb]

you want the weld to penetrate thru to the backside so you the full thickness of the panel otherwise when you grind the weld it will be to thin and pron to cracking. also try the spot weld method where you weld a spot then move a few inches away along the seam and moving back and forth until the entire seam is filled in. this way you distribute the heat across the whole panel and cut down the amount of warpage.

[Shaun @ Tru6]

slow progress. welding in 85 degree sun, not a good idea. For first time doing this, I'm happy with the results. Hoping to go out again at 5-6 tonight and maybe finish stitching.

[tabasco]

Originally Posted by 78SCRSMAN

I'm not a welding expert by any means but I would clean/grind to bare metal the seam on the back side as well.

+1.

You're nor supposed to weld with a MIG outside !
The slightest wind will disturb the gas shield.

(not a welding expert either !)

Nice job though, those flares look good.

-Guillaume

[78SCRSMAN]

good point tabasco.

I can identify with wanting to do it out doors though... garages can get hot! Add helmet and some protective clothing and... anyway, it looks good so far Shaun. You're on the home stretch now. Post some photos when you're finished.

[Shaun @ Tru6]

a little more progress. had to stop since it's over 90 out.

it's coming along slowly. won't be able to get back to this until next weekend so I hit it with a little primer. second shot is with 1 inch spacer. really happy I'm doing this. Narrow body with the 225s tucked up inside is a great look, but adding just a little more hip transforms the rear end.

[78SCRSMAN]

Shaun,
Are you using 1" spacers with cookies? I'm keeping my cookies and am wondering about spacers... look up thread (homemade cookies) How about the front?
The reason I ask is I haven't seen my car with the wheels on yet so I have nothing to go by. I keep seeing these spacers on the For Sale section but not sure what to buy.
I'm also wondering what size tires you're going to use. I'll be using 205/55's up front and 225/50's out back on 6's and 7's respectively.
Nice work BTW
Thanks,
Derek

[Shaun @ Tru6]

Thanks Derek. THere are parts that are excellent where I'm really proud of my work, and there are other areas that will, umm, require filler. Overall fit though, I'm really thrilled...reflection lines go through the two panels very well as is. This is a challenging project, but if you take your time, definitely doable. Bad news for me is that I almost certainly won't be able to revisit until August. Today is my last day off.

My car has 7x15 cookies all around with 20/55 front and 225/50 rear which just tucked up inside with -1.75 rear camber and a 23.9 inch ride height. The front fills out the fender wells nicely, no spacer needed there. We've all seen SCs and Carreras with standard 16 inch Fuchs tucked way inside the rear quarters...don't know what Porsche was thinking. With the little 15s, it looks even worse. The shop I frequent had one 1" spacer sitting on the shelf and they let me borrow it. I may have to roll the fender lip, but I think it will be a perfect fit, the tire will completely fill up the flare.

here is what the car used to be:

Temporary Perfection

[78SCRSMAN]

Hmmm... I may need 1/2" spacer up front and a 1" in the rear. I'll wait to see how yours looks when done... in August.
Thanks for the link, looks great!