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1:8 scratch deuce


Ognib

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This project is a worthy challenge & that's what attracts me to it....to take on a difficult task & see if I can figure out how to do it well.

As such, at times, it consumes my mind with thoughts of, "what's the best way to do this?".

Found myself thinking about the frame this morning.

Got my jigs & pieces down for the first time in over a year.

The rails are long pieces & I'm thinking about what's the best way to join the sides with the tops & bottoms.

I'm thinking about the heat required to join & wondering about controlling distortion & whether or not I'm going to ignite my forms in the process.

It occurred to me that perhaps it would be easier to build a male forming die & bend/shape the rails over it with a hammer & caulking tools.

It's the weekend & I'm off for a couple of days, so going to spend some time checking this idea out, since it's on my mind.

I Need to have a frame on which to assemble the body pieces as they are completed.

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Edited by Ognib
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Lovely dense, hard mahogany for the frame rail forming die.

Excellent guitar neck wood & had been set back for that purpose, but this is important here, now today, so it's being used for this worthy project instead.

It occurred to me that my aluminum side pieces are the same width as the overall width of the kit pieces & when I bend material down the sides of the die, I'd end up with an oversized frame rail, on the outside dimensions.

My plan has been to do the frame with 1/16" thick material for strength, even though that scales up to 1/2".

I'm willing to make that concession, because I don't know how much this thing is going to weigh when it's all said & done.

I'm not, however, willing to have visual dimensions that far oversized, when viewing the car from the side.

So I still have to shave it down 1/16 on each side.

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It occurred to me that my aluminum side pieces are the same width as the overall width of the kit pieces & when I bend material down the sides of the die, I'd end up with an oversized frame rail, on the outside dimensions.

Material thickness is always a consideration whenever any tooling is made for working in any material.

A way to make press dies that you may not be familiar with involves sculpting your master to the exact finished dimensions you want, making a reinforced mold from a specialty toughened-epoxy tooling material, lining the inside of the mold with sheet-wax of the thickness of the sheet metal you wish to form, and making a matching mold, again with the specialty resin.

This method produces a press-die in which you can accurately form metal parts, repeatedly. There's rather more to it than that (you also have to design for material "springback") but it's an interesting process.

The specialty resin I've used for this purpose was manufactured by Magnolia Plastics, and was proven to be able to press 1/8 inch thick steel wheel centers for a military vehicle. We also used it to successfully reproduce an experimental copy of a Beechcraft (airplane) landing gear inner door skin, a very complex shape, in aluminum sheet, using only hand-operated presses.

Here's a patent document that discusses the process in more depth, if you're interested. http://www.google.com/patents/US4601867

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Most interesting Bill, thanks.

I've been aware of much of what you said, in theory.

Had never heard of the sheet wax procedure, though.

Have done some reading on the epoxy molds.

Have thought of cutting one of the 2 bodies that I have into individual panels & pouring the epoxy over them to create the dies.

That would be a no-go if the epoxy cure generated enough heat to melt the body pieces.

Thought provoking about being able to press aluminum skins with a hand press....humm.

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I have the frame die figured out.

All that's left is some shaping.

I'm hot to see some progress down on to the side of the body.

To help my visualization process, I pulled a pattern of the kit body & drew it up on the buck.

Still way too fat on the side, back half of the wheel opening.

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The tip of the lower body panel template locates the back point of the wheel arch feature line.

Cut the excess material from the rear of the quarter panel.

That's more like it. ;)

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Re-drew the feature lines.

Still quite a bit to do, but the basic shape is getting closer.

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Been studying these.

First vids will link to a series of related vids.

https://www.youtube.com/watch?v=Ktj5DWaKXYI

https://www.youtube.com/watch?v=eMk-uJ35T0c

This one especially is relevant to my project, in that I don't have all of the power equip as used in the above Covell vids....in miniature.

This guy does it all with hammers & wood stumps.

Rough it in on a stump & use the buck I'm carving for planishing & smoothing.& detail.

https://www.youtube.com/watch?v=q6DfdOFRPFA

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Got some .008", .016" & .032" aluminum.

Domed the plastic face on a small hammer & just started emulating the techniques demonstrated in the vids I've been watching on stump shrinking.

The .008 is too light....moved too easily & was not controllable.

The .016 worked nicely, as did the .032 with heavier hammer blows & both pieces took a lot shape in a short amount of time.

About 20 min to form both.

Initial impression is that the .032 may be too thick for this project, as I'm going to have to be able to crisply define my raised feature lines in the panels, working directly on the buck with hammer & caulking tools.

The .016 has surprisingly good strength in the piece I formed with it.

This will be necessary so I can handle the model without damaging the body, later on.

The .016 piece is the one with the most shape, laying in the smallest bowl.

Time will work it all out.

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Edited by Ognib
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I gotta have something like this for planishing out hammer work.

This thing is just way too cool!

Flat roller bearing for the top wheel & the ball out of a small rod end on the other side.

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Spent some more time on the first piece of .016 from earlier.

After the hardwood bucks are complete, I will be able to work a roughed in piece like this on to the buck for final accurate shape.

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Edited by Ognib
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Thanks, Bob.

My plan is to tig it together.

This is a 1:4 Ferrari body in aluminum.

They tigged it together...you can still see traces of the weld lines on the quarter panel top, where they're in the process of metal finishing it.

More pics of this body in the early part of this thread.

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Here's a vid of a guy tigging on a .003" soda can.

https://www.youtube.com/watch?v=eX_sepp9T_M

I've considered going to brass on this & read a lot of what Wingrove has written about his work.

He has had to invest in good resistance soldering equipment in order to add pieces to a project, without previously soldered pieces coming loose from the heat.

I welded on steel bodies, daily, with mig & torch for over 30 yrs before retiring, so actually feel most comfortable with that approach to this project.

Edited by Ognib
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