1932 Cadillac V16 scale model

[Roger Zimmermann]

Here is another picture from the diff nose. From the many pictures from an original diff, the onw from under was of course missing. Therefore I had to guess and, even if the shape is similar, it may not be accurate.
I will add 2 or 3 small items with silver solder, then I will switch to soft solder: some threads at the diff output are clogged by soldering material. they can be reworked, but it's a waste.

[Roger Zimmermann]

The work is going forwards with the nose. Some details were added by silver soldering them; now, I will attach the remaining details with soft solder because due to the irregular shape of the nose, they cannot stay where I would like. With soft soldering, I have to possibility to hold them with a tool.
Most pictures I did on the original differential were at the left side; this is the same with the pictures I got from Holland. Therefore, I had to guess more than I expected how the RH side is looking like.
For the pictures, I assembled the nose to the diff body to have a more realistic impression.

[Tallen]

Roger you are a true artist! I absolutely love seeing the progress of your incredable craftsmanship. Thank you for taking the time to share your talents with us!

Allen

[Roger Zimmermann]

Thanks Allen!

The differential nose is ready. I also corrected the length of the housing by adding a spacer on the RH side. Now, the torque tube will be in the middle. As a consequence from my error: the RH shaft for the brake actuation must be extended because the bearings for the shafts are positioned at the same distance from the nose. The pads for those bearings are the next addition to the housing, as well the brackets for the shock absorbers and the brackets for the strut rods which are combined with the pads for the leaf springs.

[The Tassie Devil(le)]

Roger,

Beautiful work, and always a pity to have to cover up such artistry with paint.

Bruce.

[Roger Zimmermann]

Thanks Bruce! But you know that paint is also hiding unwanted irregularities!

[The Tassie Devil(le)]

Yes.   Bog is such wonderful stuff.

Bruce.

[Roger Zimmermann]

The differential body is almost ready. What I still have to do: create a double bearing in the middle of the body to guide the axle shafts as there is no diff pinion for that purpose.
As you can see on both pictures, I have to elongate the RH brake shaft; the one for the LH side is OK. Then, I will have to do both bearings for the brake shaft; they are attached with screws on the pads I added recently.
Other additions which were made: the brackets for the shock absorbers, the brackets for the strut rods and the resting pads for the leaf springs.

[Roger Zimmermann]

It took an awful long time to fabricate those 2 tiny bearing guiding the brake shafts. They are small and, even if I had not fat fingers, I had some difficulties to grab them for "machining". Then, to adjust them to have a free rotation of the shafts was a matter of trial and error. And, finally, by soldering the bearing (a simple tube with the proper dimensions) to the support, I had the bad surprise that everything was soldered: bearing, support and shaft!
On the second bearing, I thought that I had the perfect solution: I used a cleaned drill bit to simulate the shaft; the solder found its way to it and the drill bit was soldered to the bearing! I had to just heat it to let turn the drill bit with a plier and, during cooling, the solder joint was broken. Most probably the ideal position of the bearing was disturbed during the drill bit rescue because I had a binding situation which was solved by enlarging the inside diameter of the bearing.

[Roger Zimmermann]

The rear axle is slowly coming to the end. There are still minor elements to add: the plug to drain the oil and the one to fill it up, plus 4 grease nipples at the brake shaft bearings.
The first picture is showing my method to position the axle shafts (crude but effective) and the recently done end cover.

[Roger Zimmermann]

The drain and filling plugs were added (without picture). The big question was: and now, with what can I continue? During the winter, I prepared vaguely the pattern for the frame. It was the right time to finish it. Now, I can prepare two long brass bands; the flanges from the vertical "U" will be hammered on this thick pattern, allowing to make a RH and a LH frame rail.
I noticed recently that my bottle of gas for silver soldering is getting empty. The problem is that now stores (except for food) are closed as long that Cornora virus is active.

[Lexi]

Hello Roger. Could you use an electronic soldering pen, (no gas), like the type used for doing fine circuit board soldering? While you may not get the capillary action you need for some joints, one of these may work for pin point precision work. This is the industrial unit I use & I found it works well in those instances. You can dial in your temperature up to around 900 degrees F. Digital display and I think you can switch to C display. I think this unit has been replaced by another newer model, but something like this might do some of your work in a pinch, (but not take the place where a larger area of solder is required and more capillary action needed). Lots of control and it heats up real fast. Super accurate dial heat control as well. Clay/Lexi

[Roger Zimmermann]

Thanks Clay for the comments. Don't forget that in Europe we don't usually have the same electrical tools as in the US/Canada; Dremel is one of the exceptions.
For soft soldering, I'm equipped. For difficult assemblies which are requiring a lot of small items soldered together, I usually silver solder at the beginning and then, when it gets critical, I'm finishing with soft soldering.
Anyway, as most stores are closed due to the Corona virus, I could not buy one of the stations you are showing. The day they will be open again, I will have access to the gas too.

[Roger Zimmermann]

As the template for the frame rail was ready, it was time to bend some brass on it!
In fact, there were two options for the frame rails: trim a bit of brass the same shape as the drawing and silver or soft solder the upper and lower flanges or bend the flanges on that template. Each variant has its advantages and disadvantages. Silver soldering the flanges is creating a lot of distorsion; soft soldering the flanges is not very robust, but the rework is minimal.
The bending solution is requiring more finishing work because, as the flanges are hammered, they elongate and the rails were looking like a banana. Plus the marks done on the flanges by the hammer. I choose a brass 0.5mm thick (0.02"), therefore the material is thick enough to allow some filing to get at the end 0.4mm.
There are just 2 places I had to repair with silver soldering: at the rear, the lower flange has rather small radiuses and one had too much material (I had too cut a slice) and at the other curve, the brass sheared. I have to say that I expected more problems.

[Roger Zimmermann]

As my pattern was not thick enough, I had to skip the specific flange's shape at the rear. I silver soldered bands of brass to have the correct shape.
The main rails are not straight (seen from above) but has two bends, allowing the rear to be wider than the front. With that done, the main rails are done.

[Roger Zimmermann]

To continue with the frame, I choose the front supports of the front springs. To simplify, the RH and LH are not identical. I began with the easy one, the RH part. Easy? At first glance yes, but as all supports and brackets from that time, this was a casting. That tiny part is in fact constituted with 4 elements silver soldered. Some machining was required; the difficulty was to clamp the part which is far from regular or symmetrical. With some imagination I succeeded, without incident.
This support, which is also the base for the front bumper, is attached to the frame with 4 rivets; right now, it's soft soldered to the main rail. 2 rivets will be easy to do; they will go into the holes you can see. 2 rivets, one at the upper and the other at the lower flange will most probably be just for the show as riveting at the flanges at this scale is very difficult. This is the reason why all supports and brackets will be soft soldered to the rails.

[Ralph Messina CLC 4937]

....as riveting at the flanges at this scale is very difficult.

Roger, calling this difficult makes me think if you really, really wanted to, you could do it.

[Roger Zimmermann]

Well, Ralph, riveting is in fact not so difficult. If you saw the Mark II pictures, I riveted the blades for the fan, without soldering them. All what's needed is an "anvil" and a tool having the shape of the rivets' head in negative (hollow).
To install rivets at the flanges would require a very thin but strong anvil which can resist to the hammering. This is what I will maybe do or have just dummy rivets.

[Roger Zimmermann]

After the RH front spring attachment point was done, I began the LH one which is different. While I was drawing the "workshop sketch", I noticed that the casting is longer than the other side; therefore, I had to shorten the frame rail. I had previously done the holes for 2 rivets, they are now closed with soft solder as the correct ones are located about 2mm towards the rear.
The big question is: why this attachment point is so different that the other one? I'm not a connaisseur from the cars build in the thirties; I don't know if every car had that difference or only the expensive brands. By the way, the LaSalle models had that too.
Those who have such a car, please let the other people try to find the right answer! The solution will come in a couple of days.

[Roger Zimmermann]

Well, the number of suggestions did not disrupt the forum! Here is the answer:
In the Cadillac world, this arrangement was called "steering modulator", with following explanation: The steering modulator is designed to prevent shimmy and steering wheel whip. To accomplish this, the front shackle of the left front spring floats between two pairs of stiff coil springs. With this arrangement, the modulator springs absorb the road shocks which may otherwise be transmitted to the steering wheel.

If the system was functioning as intended is a question I cannot answer. This was eliminated when the independent front suspension was introduced. I'm adding a picture of the system used by Cadillac.