Roger Zimmermann

Construction of a Continental Mark II model, scale 1:12

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During my vacation, I studied how I could do the vanes or fins for the wheelcovers. As I had a lot to do after my return, I could not try my plan immediately. I dit it this morning and created the prototype of the vanes. It took about 1 hour to get it; once the set-up is done, it will be quicker, at least I hope so: there are 40 vanes per wheelcover.

As the result is the way I expected, I ordered 10 feet of 1.5 mm thick brass!

I ordered also round brass diameter 40 mm to do the dies for the "dishes". I still don't know if I will do the wheelcovers in one piece or if I will be forced to do the center as one piece and the outside diameter as another part, soft soldered together. With steel dies and a strong press there would be no problem; however, I can only work with brass and if ripples are formed during the process, they will damage the dies if too much pressure is applied, without eliminating the ripples as I learned when doing the wheelcovers for the Avanti.

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The brass needed for the wheelcover will be available next week. In between, I finished the wiper motor; the mounting plate was still missing. Thanks to the various dimensions I took from a real car, I could complete the motor.

On the picture, it's amazing to see the dirt on the part; it will surely be cleaned before painting!

Total length is about 1".

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Hello Roger,

As I follow your intriging skills and amazing patience, I am recalling similar construction problems. In 1962 employed by HMS Co as a modelmaker we created original car models for the Aurora Co. To reduce air bubbles when pouring silicone or epoxy mix, use a paper drink cup (dixiecup), combine the two components, then put cup and mix into the vacuum chamber. Once the air stops breaking the the surface, remove cup and instead of pouring out over the lip, penetrate the cup wall close to the bottom using a pointed scriber to open as large a hole as needed. This produces the least bubbles in the mix.

Thank you for the thorough description as you create your art. Phil

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Phil, it's an interesting method! Fortunately for me, the tires problems are solved. I had also the luck to have a product which was not too thick with a 2 hours curing time, letting enough time to avoid problem with air bubbles.

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While I was waiting for the brass to turn the forms for the wheelcovers, I decided to begin another pair of interesting parts: the valve covers. For those who don't know how is looking a Mark II valve cover, the first picture is showing a dirty real one.

How to do that? An aluminum casting like the original parts? Unfortunately, I'm unable to cast something except silicone rubber...

I imagined two ways. The first one was to do a valve cover with a sheet of brass, then cut grooves to insert thin brass pieces to form the fins or ridges. Unfortunately, I had no tool of the proper shape for that task. Therefore, I had to turn to the second solution:

I cutted 31 pieces of .8 mm brass with a hole in the middle to fix them during the rework. (second picture)

Then after some hours of filing with rather high tempereature (should be a winter job), I got the definitive profile of the cover. (third picture).

After that, I cutted 32 thinner pieces of brass, again with a hole in the middle and assembled one thin part with a larger one, then a thinner one, and so on, like a sandwitch. (fourth picture)

The shape was done again with a file (due to the odd shape, machining is not a solution) and then the assembly was brazed. (last picture)

The next step will be to finish the shape to the correct dimension and braze the assembly to the base.

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Incredible, Roger!

Not quite: it's mostly inspiration or imagination and right now, perspiration!

When the available equipment does not allow to replicate the way it was done originally, you have to be a little bit creative!

By the way, thanks to your pictures, I was able to dertermine the proper dimensions of these parts. Again, thank you.

Edited by Roger Zimmermann
text added (see edit history)

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Roger, enjoy watching you work. How many hours do you think that you have in that one valve cover so far?

Me too, on your Avanti! You are publishing pictures I would have love to get when I was doing that model!

You are asking a difficult question...Never count the hours, just the years...I think I had up to 10 hours for what is done now. Usually, the second piece is done quicker; anyway, as most is done manually on this kind of part, there will not be a great difference with the second valve cover.

To Barry: I'm using a rod with 45% silver content and a propane torch. Is that what you had in mind?

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We call that soldering. What we call brazing is using brass to weld metal parts together.

It's what I'm doing, with a brass/silver rod. The bonding agent is called "Castolin 1802"

I wanted this morning to get the specification of this product; unfortunately, the site is not working.

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Learned something new today.

Found another site. The material is getting liquid by 1200 degres F or 630°C.

What you are calling soft solder is liquid at about 400°F or 220°C. This art of fixing parts together will be used for the remaining parts of the valve covers for practical reasons.

Edited by Roger Zimmermann
completing the text. (see edit history)

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Today, I finished both stars going on the valve covers. As you may imagine, the most time spent was to do the 4 holes into the star. Both pieces were soft soldered together; the irregularities on one are to be found on the other.

Before to solder them on the valve cover, I will attempt to improve them a little bit. On the other side, I have not to forget that the parts seen on a computer screen are X times larger than reality, rendering the irregularities more obvious.

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It took a long time to mill the recess for the emblem, but at least I was more or less satisfied. I corrected a little bit the star; not too much as the danger is more to harm as to do good.

I then soft welded the star on the cover. Unfortunately, it was offsett by 0.1 or .2 mm. Maybe the next one will be better (but usually worse)!

I noticed also that the star on the valve cover is not symetrical; it is in line with the attaching bolts. I had to shorten a little bit (.2 mm) one leg of the star to be more or less in line with the original design.

To finish the covers, I have to do the end caps and solder them to the main corpse.

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Wow what a read for a saturday morning!!! Just found this thread and am in awe!! Keep up the work and I look forward to watching the progress

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I've registered at this forum only so that I can subscribe to this amazing thread and see the updates. Roger, your skill and dedication is inspirational! Thank you for your story and your photos.

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