Pocher 1/8 Alfa Monza revisited

[Jo NZ]

Thanks for the pictures! The detail I am still looking for is how the extension pipe to that vent fits to the clutch housing - as seen on the Monza. Is it one tube to a flange, or does it attach to the filter extension somehow ?

Jo

[koehlerkment]

Hi Jo,

the tube is fixed to the bell housing with the flange.

Klaus

[koehlerkment]

After some searching I found a picture of a Monza model by Fine Art Models. The air vent tube can be seen here and it is obvious it is directly fixed to the bell housing.The model was probably made by Misko car models: http://drmischko.com/misko.swf?x=12-11-6-7-6

[Jo NZ]

Got it - a simple flange and tube. I've turned a piece of sprue and inserted it into the bellhousing to provide the flat boss for the flange.

[Jo NZ]

Here's the flange (I turned and filed it, I am all thumbs making one from sheet), and in position with a scrap piece of 1/8" soft aluminium wire to make the pipe

[Jo NZ]

I got the advance and retard kit from MMC (thanks, Marvin) and wondered where the other end of the vertical link went.
It connects to a lever on the side of the steering box - the advance/retard operating lever is in the middle of the steering wheel and the movement is transmitted down to the steering box via a tube around the steering shaft, and then a gear to drive the operating crank.

Here's the completed installation

[Jo NZ]

The back axle: having already machined the brake drums, I thought I'd try the brake backplates. Made from 6mm plate, like the drums, this is about the limit of the diameter that can be machined on a Unimat 3.

Here's the first one. The annular ribs are machined with sharp edges and then sanded on the lathe to take the corners off. The boss for the brake lever is made separately. I drilled and tapped the backplate before shaping, and cut a partial thread on a 5mm rod. Screwed in it nearly looks cast in one piece.

Assembled:


And finally tumbled with ceramic chips to give a matt finish:

[Jo NZ]

Now I've looked at more pictures I realise that the backplates in the kit are not correct - the hub insets into the backplate and the carefuly made sleeves for the brake levers are fiction! Maybe I'll get them right on the next Monza...
Continuing with the back axle theme I've moved on to the rear spring hangers. I've remade the front ones, using ceramic tile trim to get the correct thickness and shape of brass angle. The bush is turned from brass rod, and the rivets are brass nails...

[Jo NZ]

A quick one - looking at the rear chassis tube the kit is not the same as the full size car. The kit has the M2 threaded rod, with nuts and washers on each end, whereas the car has a cap on the outside of the chassi rail - like this


The chassis tube is the perfect size for tapping M3, so I tapped each end and cut the head down on M3 screws to mimic the cover plate, then drilled out the chassis holes to 3mm. It still screws together and looks much better....

[Dougritt]

Jo NZ-
Thanks to your ace research work, my car will get much more accurate...thanks! Your Alfa is looking sweet!

Doug

[Jo NZ]

Thanks Doug!

I've been avoiding the chassis brackets for the front axle tie rods for some time, because they are a complex collection of angles...

The bracket is angled in towards the centre of the chassis to line up with the axle fixing.

I decide to silver solder this one - I thought I might have multiple steps to perform, so a joint that wouldn't remelt with soft solder seemed like a good start. The iron wire won't stick to solder, and holds it in the correct shape


Cleaned up...


and with the yoke added


Extra material removed and bolted to the chassis


The modified tie rod


Finished - now for the other side...

[Jo NZ]

I started the radiator a year ago, trying to silver solder the first stage - with this result


I had a second try, which while not as bad, still had gaps around the join.

Taking a look at it after leaving it for a year, it looked salvageable, so I filled the gaps with soft solder, cut it back to the correct thickness for the radiator, and tried again

This looked workable!

The only picture I've found of the back of the radiator shows a pipe between the top and bottom outlets, which appears to connect the thermostat housing at the top with the outlet pipe at the bottom


The thermostat housing and cover flange are both curved sided triangles, known as reuleaux triangles. After a few false starts I machined it like this


Here's the Radiator so far...

[Jo NZ]

The bottom hose connection was easier than I thought...






The radiator assembly is on hold while I discover how to soft solder stainless steel to brass, so I decided to complete the plug wiring and the strut from the radiator to the bulkhead.

[Jo NZ]

The oil tank: It's supported with a short chassis crossmember at the front, and is hung in straps like a regular fuel tank.

Here's the chassis extension





Strapping the tank





I've remade the boss for the oil filler tube to take a square flanged one. It's made from 7mm dia brass rod, annealed and hammered into a sharp bend, and then shaped. It took 3 anneals to get it to a right angle.



Fitting to the chassis



Installed

[Jo NZ]

The oil filler cap is finished apart from plating...