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1932 Cadillac V16 scale model

Started by Roger Zimmermann, July 12, 2019, 01:40:19 PM

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Roger Zimmermann

Now that I'm more or less confident with the tires "manufacturing", I would like to refresh the steps needed for that.
1. make a master tire with brass or something which can be machined
2. make half molds from the master tire; they are negative molds
3. make positive molds (or two half tires) from the negative molds
4. make negative molds with a resin which will be hard after curing
5. finally by using the negative resin molds, do the final tire (s)

I see an argument: why don't use the half molds described under the point two?
By using those RTV molds, it would be necessary to use separating wax for each tire. This is not a big deal, but if the wax is not going everywhere, the tire will get bonded with the mold, destructing it. The next argument with the way I'm doing the tires: by applying much pressure to the soft molds like shown with the attached picture, I doubt that the end result would be usable.
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

Roger Zimmermann

Due to the GE and summer vacation, there was nothing to report. Now, I'm back and some progress was done: most tires are ready, I intend to do a last one in the next few days. With enough tires for the model, I had to do the knuckle arms to be able to install the front wheels. The shock absorbers are temporary installed too; I still have to do the actuating arms.
Now, I will do the tie rod ends and the tie rod because it's annoying when the front wheels are totally independent from each other...
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

Roger Zimmermann

For two days, I intended to cast the last tire. After 8 hours, it was time to open the molds; the result was another perfect tire. I sanded the parting line, and, after cleaning, I noticed that the tread was damaged at three places. Like two or three other tires, the missing bit of rubber was at the rear half. Strange...Why nothing is missing at the front half? By looking at the workplace, I saw two tiny black things with teeth! Effectively, those small rubber elements could be placed into two holes. Why? The answer is at the hard mold: when I began to cast the positive flexible molds, some rubber went under the brass bands. This "characteristic" went 1 to 1 to the hard mold, and, at those places, the tread is not attached to the root of the tire. With rough movements like with sanding, the rubber got thorn.
As I could rescue two elements, the sole way to put them in place is to prepare some more rubber. No chance to have the right proportions for a tiny quantity, so I decided to eliminate as well as I could the flaws from the mold and do another tire which was done today. I will now be very careful by sanding the parting line...
Anyway, I could not resist to take a picture with the product under vacuum. The volume for the product is about 4.5 cm3. The available volume from both containers is about 60 cm3. As you can see, the level rose almost to the top of both containers...Incredible!
Now, I have 8 tires; each has some small failures...The really bad ones will be used as spare tires as they are covered with a nice cover, so the tire itself cannot be seen, + 2 tires, just in case.

I began the tie rod ends; for the moment I have 4 pivots. They are made with mild steel and a ball is silver soldered on one end.
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

Lexi

Quote from: Roger Zimmermann on June 12, 2022, 01:29:43 PMI see an argument: why don't use the half molds described under the point two?
By using those RTV molds, it would be necessary to use separating wax for each tire. This is not a big deal, but if the wax is not going everywhere, the tire will get bonded with the mold, destructing it.

Roger not sure if this would work in your situation but sometimes I used waxed paper as a separator. It allowed for separation of the 2 parts later. Other times Vaseline sometimes cut to make it flow more smoothly. Similar methods used when wood turning with 2 halves joined together by newsprint which had been sprayed with Elmer's adhesive. Holds together well to support turning but can be cracked open later. Probably not good for your tire project but perhaps the waxed paper idea may work? Keep up the great work. Clay/Lexi

Roger Zimmermann

Clay, the waxed paper can only be used to separate two element which must not stick together which is not the case for the definitive tires.
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

Roger Zimmermann

With the tire saga behind me, I continued with the tie rod ends. They are not done like modern ones: there is a cap; inside the cap there is a strong spring pushing at the lower pivot seat. I did the same, with the exception of the internal spring. By adjusting the cover with some precision, I'm getting a pivot without play and I can add some grease after the final paint.
The tie rod was one of the easiest parts to do: just a straight rod with threaded ends...As I don't have LH taps, I did RH threads at both ends, like my other models. The adjusting for the toe-in is just a bit different than in real life.
I noticed that the tie rod is lower than the front axle. Not very good...According to the drawing in the shop manual, the front axle should be a tad lower than the tie rod. I will bend the knuckle arms to reduce this inconvenient.
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

Roger Zimmermann

With the shock absorber bodies done, it was time to link them to the suspension. This was done the last few days. The long screw at the arms is temporary. It must be that way till I'm ready to install the O-ring at the shaft. Once the arms are permanently attached to the arms, the O-ring cannot be installed or replaced.
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

Barry M Wheeler #2189

Roger, I only check on your progress about every six months. But every time I look, I am astounded with the level of your craftmanship. That you can do all of this work is utterly fantastic and words cannot describe it.

As always, never give up, and thank you again for keeping us apprised of your progress. Best, Barry.
Barry M. Wheeler #2189


1981 Cadillac Seville
1991 Cadillac Seville

Roger Zimmermann

Thanks Barry for the kind words!
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

Roger Zimmermann

When a sub-system is finished, the question is always the same: and now, with what I do continue? This time, the answer was: gas tank. I have no dimensions from it, but enough picture to have a good estimation.
I did first a dummy tank with cardboard to see if it would find its place. After that, I did the profile with heavy stock. This allowed me to shape the ends as well as the baffles to be soldered inside the tank. Their purpose is not to avoid heavy movements from the fuel, but to avoid crushing the tank by lifting the model by the gas tank.
The real fuel tank has two creases at each end; I was not sure how I would replicate them. Then was the choice of the material: 0.1 or 0.2mm thick brass? By trying with waste material, I came to the conclusion that the 0.2mm was better suited for all the operations to be performed on the main parts from the tank.
I did first the creases with a 0.8 mm wire pushed on the brass, then rolling the plate to get the correct shape. The last picture is better explaining the task.
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

Lexi

Roger looks like you forgot to upload your photos. Don't see anything, at least at this end. Clay/Lexi

Roger Zimmermann

Strange...When I checked if the pictures were there, I saw all three. Now they are gone...I'm trying again.
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

Lexi

There they are. That gas tank looks fantastic. Clay/Lexi

Roger Zimmermann

The gas tank is now almost ready; the side plates were not flat but to simplify the stamping, I just soldered a convex smaller element. Missing are the tiny details: the three brackets to attach it to the frame, the draining plug and the filler tube which will not be easy to shape.
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

Roger Zimmermann

Ah! Summertime...Not the best season to build scale models! Anyway, I added some details to the tank, like the draining plug and the fuel outlet. Then I began doing 3 attaching points to be soldered on the tank. I evaluated their dimensions according to the pictures I have from Johan; I'm sure they are similar to the real thing but inexact dimension wise. I added also fake rivets to the straps.
Two minor pieces must be added to the tank: the fuel sender and next to it, another round cover I have no idea about his function.

465 fuel tank rear.JPG

466 fuel tank front.JPG

467 fuel tank side.JPG 
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

carguyblack

Roger,
At the risk of swelling you head yet again, most artists couldn't even draw this stuff let alone produce it to scale from scratch in metal.  I stand in amazement!
Thanks for the continuing photos of your work in progress.
Chuck
Chuck Dykstra

1956 Sedan DeVille
1956 Coupe DeVille (2 sold)
1957 Oldsmobile 98 (sold)
1989 Bonneville SSE

Roger Zimmermann

Well, Chuck, with a cold shower everything is back to normal. Anyway, thanks for the comments!
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

Roger Zimmermann

While doing the steering gear arm, I noticed "ears on the side. Suddenly, I found the reason for those ears. Do you have an idea about their purpose?

DSC01267.JPGDSC01268.JPG 
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

The Tassie Devil(le)

For bashing with a big hammer on one side, and holding an even bigger hammer as an anvil on the opposite side?

This action will shock the splines loose to allow removal, as there is no room for the normal Spreader to get behind the arm.

A case of shock and awe, the shock that one has to belt it so hard, and the awe that it came off so easily.

Bruce. >:D
'72 Eldorado Convertible (LHD)
'70 Ranchero Squire (RHD)
'74 Chris Craft Gull Wing (SH)
'02 VX Series II Holden Commodore SS Sedan
(Past President Modified Chapter)

Past Cars of significance - to me
1935 Ford 3 Window Coupe
1936 Ford 5 Window Coupe
1937 Chevrolet Sports Coupe
1955 Chevrolet Convertible
1959 Ford Fairlane Ranch Wagon
1960 Cadillac CDV
1972 Cadillac Eldorado Coupe

Roger Zimmermann

Bruce, I don't understand exactly what you are writing, but it's also my opinion: to remove the arm, either with a tool or with hammers!
1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101