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Old 05-08-2009, 07:34 PM
Kerry Pinkerton's Avatar
Kerry Pinkerton Kerry Pinkerton is offline
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Location: Near Huntsville, Alabama. Just south of the Tennessee line off I65
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Default The Art Deco Imperial Project - Part 5

THE ART DECO ROADSTER PROJECT
6/10/07
FINALLY back to work on the roadster!

We took the fender buck to SunNFun but never had time to mess with it. When we got back we kind of fell into a major renovation project on the shop that has pretty well consumed me and I've still got a month of work to do.

Today I just had enough. Time to make some shape!

At MM06 I bought a set of Loren Richard's Phenolic Thumbnail dies from Stan Fulton. Originally, I was going to make my own tool posts but life got in the way and I just called Stan and ordered them.



These things are GREAT!!!! Designed for aluminum, they shrink like a SOB and leave no marks on the aluminum. I have a set of Clay Cook thumbnails that work great in steel but mark aluminum a little.

I've spent a lot of time thinking about how I will attack the fenders of the roadster. How many pieces, where to weld the seams, etc. After a couple practice pieces to get the hang of the dies, this is the result. There is about 45 minutes in this piece.



Here is a more frontal view of the fender. The other side will be a mirror image. Welded in the center.

Another approach would be to have a center section and side sections. Might try that.



I've borrowed a deep throat marchant type shrinker and will be using that to make the inner cockpit structure, door frames, etc for the roadster. They will be 16 ga steel. I'm going to try and find some 16 ga tomorrow.

Good to get back to metalshaping.... This construction stuff is boring!
6/15/07
Some progress today.

As I roughed out the other half of the fender, I used the double tape approach that Casey Hill showed me last year. Richard Crees posted this drawing which shows how it works.



This is one slick, accurate way to get an EXACT cut line! Thanks to Richard for the drawing.
1- Take masking tape (or any tape really) and CAREFULLY lay it down with one edge on the exact place you want the other panel to line up, that is, the cut line. The red tape in Richard's drawing.

2- Lay the second panel in place. Unless your overlap is extreme, you should see some of the first piece of tape sticking out. If not, do a rough trim until you do.

3- CAREFULLY lay a new piece of tape over the top of the first piece lining up the edge perfectly. The blue tape in the photo above. Part of the tape will be on top of the first piece and part will be on the second panel.

4- After you make sure the tape is secure to the second panel, pull it off the first piece of tape (or cut it with a razor blade etc). The edge of the tape is the cut line. Since the tape is the exact same width, if you were careful in laying both pieces, the edge of the second piece should be exactly transferred to the second panel.

5- I used 1" blue painters tape but I think most anything will work. Remove any sticky residue before welding of course. Richard used red and blue so you could see how it works, obviously you don't need to use different colors of tape.

When Casey Hill showed this to me I stared at it a couple minutes before it clicked. It wasn't until I took some tape and tried it that it really made perfect sense.

I finished the other side of the fender and tigged them together.



I'm a rank amature at TIG. When I tacked this together it was pretty ugly. Remembering that Dick Bear had talked to Wray Schelin about this very subject when he was working on the McBearn, I dug up the post. It bears repeating...this is GOOD STUFF!


Quote:
Originally Posted by Dick Bear
I can only assume that the 57 members who viewed this post between the time I posted it and the time of this reply were also interested in how to finish-off a seam like the masters.

Shortly after my original post I received a call from the Master of All Masters, Wray.

He explained that he has in the past posted information on the procedure he has found to be the most effective over his lifetime of metal shaping but that that information has always been lost in the deluge of collateral (related and unrelated) information that usually accompanies posts on MM.

During our phone conversation Wray went through the prep and procedure for me and I am passing my notes from that conversation on to all. I am acting solely as the messenger here and in no way believe that because the information came to me from the Master I am threfore one of them.

I (like you) will be practicing these techniques while finding it reassuring to know that what I am doing is in-line with the proven methods practiced by those who repeatedly produce professional results. Here are my notes:



Aluminum and Steel Seams and Finishing
(Wray S/Dick B conversation 4/11/06)




PREP:
- Cut weld filler rod from stock material
- Chamfer panel edges 1/2 the thickness of the sheet material
- Cut weather strip copper backing 1 1/2” in width
- Use “Red” label Tungsten rod 3/32” dia.
- Tungsten point: - Form a sharp point with a 5/16” bevel



TACK WELD PROCEDURE:
- Once panels are formed to hold a neutral position in perfect alignment
- Bevel each edge of panels to be joined
- Place copper strips on backside of seam
- Tack weld in 1 inch increments beginning in the middle of the seam
- As each tack is made watch to see if the ends of the panels begin to cross over one another.
If they do:
- Carefully grind-off the top dome of the tacks and using a hand held anvil on the back, tap the tack(s) until the panels re-align themselves.
- Continue tacking… watch for panel cross-over until entire seam is tacked in 1” increments



FINAL WELD PROCEDURE:
- To concentrate heat, hold Tungsten tip as close to beveled seam as possible without coming in contact with molten filler material
- Weld in one inch lengths filling bevel trough with “proud” just slightly above panel surfaces using traditional Tig welding technique
- Skip around seam to avoid building up heat too much in one area
- Lightly plannish any area that becomes distorted and continue in segments until entire seam is welded
- Carefully grind-off “proud” were needed
- Plannish seam smooth with hammer or slapper


That’s it! That’s the Gospel According to Wray and I’m going to follow it to the letter.

For those of us who had no idea of the time one should expect to spend on a weld here is a shocker for ya….! Wray figures one hour’s time for each foot of normal weld. So, if your family is waiting one you to go to the mall, may I suggest that you wait to weld that seam at a later time!

Dick Bear



I had already beveled the edges and had a tight fit but was blowing holes and making globs. Today I cut a strip of copper and clamped it to the back. MAN WHAT A DIFFERENCE! Someone could look at this and almost think it was possible that I might have a clue...



Still have some arrangement to do but there is no sense in doing that until I get more panels in place. Everything fits tight to the buck except for the very bottom where I need to do some more shrinking to get it to roll under a little more.

My combination steel and wood buck seems to be working fine. The front half of all for fenders will be the same. I will make another buck for the back fenders before Dutch's meet.



The inside still has a couple problems that I need to address with the TIG. A few low spots that need a little filler rod.

I'm using 1/32 1100 rod. The 1/16 rod doesn't want to melt into the puddle as nice. I really need to practice advancing rod with one hand. Well...I just really need to practice period.



This entire fender may or may not be used in the actual car. This is more or less an experiment on how I will build them. I'll probably learn enough to decide to do them different and I'll just hang this one on the wall and start over with lessons learned....or not.

Realism is setting in also. Originally I stated I wanted to metalfinish and clear coat the car. That probably won't happen. The last 10% efford to get it perfect takes more time than I'm probably going to be willing to do. A little 'thick primer' will probably be in order. I hate to block and color sand though so who knows. I'm old enough that I'm entitled to change my mind...if I can remember what I decided yesterday to change it....

6/15/07

Hard to think that it took me a day to get this done but...

The next thing I want to do is build the cabin structure that the aluminum skin will fasten to. This will be a slow process and I'd like to get it pretty much done before I haul the car up to Dutch's meet so we don't have to sit around doing grunt work and focus on shaping and welding.

I've talked to a couple pretty knowledgable people about this. Dutch Comstock continues to share his wisdom and experience which continues to be invaluable.

James Bowler built an all aluminum Ferrari and had some great suggestions. James build a magnificent full size wooden buck, built the body, built the chassis, and then fit the body to the chassis. If he had it to do again, he said he would just build the body ON the chassis which is the approach I'm taking. James also used .080 aluminum for his inner structure but said if he was doing it again he'd use steel so again I'm taking that approach.

Ideas or suggestions as to how to approach this, or other aspects of the build, are always welcome.

The car will have 16 guage steel angles that support the structure of the skin. The firewall will be 14 ga steel (probably with an aluminum face> I already have the 14 ga and its heavy enough it won't need any beads so the firewall will be slick and smooth. Once everything is fitted to the wood and all the holes are in the final location, I can transfer to the steel and swap out the wood.

Some months back I cut a piece of plywood to use as a mockup firewall. I was happy with the profile so I just needed to make angles that matched the outer edge.

16 ga is fairly stout and will be very stiff once it's all tied together.



In this photo you can see the wooden firewall mockup screwed to the steel frame. You can also see the cabin outer frame which is 3 1/3x3" 16 ga angle. It sits on 2" urethane body mounts and is also spaced 1/2" off the outside of the frame rails. For now I've got the urethane and 1/2" spacers taped in place with blue maskng tape.

The various angles will be welded to the outer frame as will the floor stringers and finally the floor. Richard Crees recommended not welding the floor down until construction is further along for accessibility.




I had two ways to go in getting the angle from straight to the shape of the wood. Fabrication and shaping. Same result but different approach. Fabrication involved cutting slits, bending the angle to the approximate shape, TIGing it together, grinding the welds smooth, and touching up with the shrinker stretcher. This side is the one that was fabricated. The other side was all shaped with the Lancaster shrinker/stretcher. The are welded together in the top center.

With all the framework I've got to do, I wanted to evaluate my options. Actually it turned out to be faster to shape it than fabricate it.


You can see the Lancaster marks as well as where the cuts were made in this photo. All this framework will be covered so I'm not concerned about the cosmetics.

It took longer to lay the two pieces on top of each other and tweek until they were identical than it did to make them.

Next I'll mount the frame rails and start tacking the various structures together. Once finished, I'll put in gussets and braces so it's rock solid. I'll make the door jambs and frame the same way, but weld two angles edge to edge to create a C instead of an L. The outside will have a bow in both directions.

If you've ever taken the skin off a car, you'll understand all the internal structure and bracing that gives the body it's strength. I'm going to err on the side of more structure since I have lots of power for the weight of the car.

I'll probably rosette weld it to the flange. The aluminum firewall will probably be 'bonded' to the steel firewall with panel adhesive. Dang I wish I could do a CAD drawing....

Still haven't decided how the body will be fastened together. After playing with rivets at SunNFun I'm considering that approach where hidden bolts won't work. Alternatively, I could bond aluminum to the steel and rosette weld (spot weld like) the aluminum to aluminum with TIG.

Don't really have all the answers yet. Heck I don't even have all the questions yet either.
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Kerry Pinkerton
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