Sectioned and Channeled Pocher Alfa Spyder

[Pouln]

David, what you are creating here is a master piece. It is simply brilliant how you bring this model to correct proportions.

Happy to see that you could use some of the input I provided back then.

I’ll be following your build as I can learn a lot from what you are doing and I’m sure any Pochet Alfa builder can learn a lot here.

 

You make it all seem quite easy to implement all these modifications. Of course it is not that simple. What we see are the fruits of many hours of thinking ahead, measuring, planning building, and then again thinking where you can improve etc.

 

great job,👍👏

[Endeavor]

Thanks, Poul

 

It's great to have you back.

[Endeavor]

 

Fitting the new doors

 

 

 

The passenger's door with the inner styrene skin

 

 

 

Both doors now fit fairly well.  The jambs require more work.

 

I had problems getting the styrene to adhere to the aluminum, until I learned that CA is much better for this application than two part epoxy.  (Thank you, Jo.)

 

 

 

I began to work on the engine.  I will not document this in much detail, as it is really pretty straight forward, many builders have shown their work on several forums, and many have done more detailed higher quality work than I.    See Jo's engine in larchiefeng's Pocher F40 thread.

 

The real reason for documenting the engine build is to provide evidence that I really did install the crankshaft, rods, and pistons.  The assembly spins smoothly.  When built, this will never be seen again.

 

Below is the assembled bloc and the major Pocher components.  Assembling the block,  removing mold marks, and repairing and correcting the Pocher parts is a time consuming undertaking.

 

 

Repairs to the kit parts to date included correcting the warped head, cleaning up the cast parts- particularly the  manifolds, blower, and carb, and aligning every mating surface.

 

Modifications done to date include that the two halves of the block are "welded" together, the block is reinforced internally with styrene, the screws were replaced with styrene rods, and shelves were installed near the top of the block so the head can be secured with screws hidden under the cam covers.

 

Modifications planned for the future include that all engine components, except the head, will be installed with pegs rather than screws, brass gaskets, tunnels through the rear engine mounts, and building a proper steering box mount.  

 

Hardware from Model Motorcars will include spark plugs, water pipes, breathers, brass bolts, and decals.

 

The engine is mounted 10mm back, the front cross member was moved 10mm back, and short styrene rods will replace the screws for the rear engine mounts.

 

Below is the proof that that the welded block has all the Pocher internal components.

 

 

 

 

 

I made a big mistake.  

 

Because I moved the firewall forward so that it is flush with the leading edge of the cowl like the prototypes, it is too close to the engine.  The firewall is too deep, probably because it was originally made to fit the Pocher Monza.  This may be why Pocher recessed the firewall into the Spyder cowl.  I have not been able to determine exactly how deep the firewall should be.  By comparing its depth to the size of the engine components in photographs, I believe it is about 4mm too deep.  A 4mm move is shown by the pencil mark on the firewall in the photograph below.  I will have to do one more operation(s) on the firewall, reducing its depth while attempting to maintain its correct appearance.

 

[PROPELLER]

Scratchbuilding without mistakes is not scratchbuilding!

Welcome to the club...

 

Well, on the engine don't forget the supports of the steering box,

a Pocher's omission:

 

 

Dan.

[Jo NZ]

...and don't forget to cut the inlet manifold in half...

[Codger]

This thread has become 'The Book' on building Pocher Alfas. The talent of David and the small army of experienced contributors has made it so.

So much applies to constructing others, that all Pocher lovers should be grateful.

My thanks to all for sharing advice and secrets...

[PROPELLER]

But I forgot, me too, to mention the big holes each side on the cross section of the engine block...

 

 

Dan.

[SA80A2AR]

20 hours ago, Endeavor said:

.

ohh   lots of shiny bits

 

nice build anyway

Edited March 31, 2019 by SA80A2AR

[larchiefeng]

Wow, milling the engine block and adding the holes on that machine really makes me feel like a shade tree mechanic with the way I did it! This is why I don’t feel any need to start a thread for my Alfa. This thread and others are so much better than anything that I could offer. Great work David!

[Pouln]

Wayne, still your experience in building the Alfa would be a welcome addition to what is here already. 

There must be some lessons learned for others and me in it. 

 

No hurry but when you find the time and motivation.....

 

Funny that no matter how much you think and plan in advance, these Pochers still force you into the doing-redoing and yet another redoing cycle.

I think it is called building pleasure😜

[Endeavor]

Thanks for the comments and suggestions, Guys.  It is much appreciated.

 

The the pencil line in the photograph below marks the next saw cut on the firewall.  A 4mm section to the left of the line will be removed to move the lower forward section back a bit..

 

 

 

Once again, you see the firewall in two pieces.  The 4mm section has been removed from the sides of the firewall.  Due to the slope of the top of the firewall's forward section, the top fits into the rear section, so the rear section will be trimmed and reshaped, then the junction will be filled and shaped.

 

 

 

The two pieces were welded together.  The rear section has been trimmed a bit, but more filing is required before the join can be filled with Milliput.

 

 

 

 

 

Below is a factory drawing, taken from Paul Koo's CD.

 

Note the proportions of the firewall and the position of the engine relative to the firewall. 

 

 

 

The photograph below shows the position of the bell housing relative to the firewall and floorboard of a prototype.

 

 

 

Below is the still unfinished firewall, engine block, and head placed in position.  

 

The engine has been moved back 10mm, the leading edge of the cowl is in the stock (and correct) kit position, a 7.5mm horizontal section was removed from the cowl and the top section of the firewall, the firewall has been moved forward about 4mm so it is flush with the leading edge of the cowl, and the lower forward section of the firewall has been moved back 4mm.

 

The white styrene tube was installed to simulate the "tunnel" through the left rear motor mount. Still a work-in-progress.

 

 

 

Below you see the position of the engine relative to the firewall, radiator shell, and bonnet.  It is tilted because it was just placed loosely in the chassis for the photograph. 

 

[harveyb258]

Yet another masterclass of plastic surgery!!

Great job, David!

[SA80A2AR]

very nice.  are you going to paint and weather the engine?

[Pocher Perfectionist]

Wow; I too have this project underway and got it back out to try complete - Though must say I thought I was the only one crazy enough to attempt such body proportion corrections! Having a look an measure of an actual full size Alfa 8C I too discovered much of what you've undertaken. Although its the doors and cabin which became a poignant correction and needed to be lengthened (approx 5mm)  You may also discover that the entirety of the fenders are wider (and mounted slightly higher) on the real car (from memory maybe I widened with a 3mm plastic splice in my build, contoured with milliputt and also reshaped the ends) I'll look forward to future updates as I'm at a similar stage and was seeking for further inspirement and Um Endeavourment - You're it!

 

 

Edited April 11, 2019 by Pocher Perfectionist

[Noel Smith]

Interesting project progressing well! Will follow progress of this one.

Edited April 11, 2019 by Noel Smith

[Endeavor]

Thanks for all of your comments...

 

SA80A2AR - After all engine components have been finished and fitted, the engine will be painted. I plan to "weather" it just a bit.

 

Pocher Perfectionist - I am very pleased that you are undertaking to build the K73 with the same objective.  I have shown the build in detail in the hope the this will encourage others to undertake the same kind of effort with this and other Pocher kits.  Being able to study the similar and usually superior projects of others has been, and continues to be, very helpful for me.  

 

I hope you will start a thread of your build.   

[Pouln]

Wouldn’t that be great? Two builds of highly modified realistic spiders at the same time.

Double the amount of solutions for challenges and inaccurate Pocher components.

 

We’d love that Pocher Perfectionist 

[Endeavor]

More work on the firewall.  I filled in the joint created by the latest surgery, drilled holes for electrical system wires, and added "feet".  Not a complimentary photograph.

 

 

 

Below you see the first cuts made in preparation for building the new, hopefully more accurate, steering box mount location.  I cut the hole and removed the inaccurate bulge and the peg that located and secured the kit's steering box.  You can see the "shadow"  left from where I removed the "bulge".

 

 This was just the first cut.  It was an iterative process.  It was necessary to cut away substantially more material both on the lower edge of the opening and also to cut closer to the cylinders.

 

 

 

Here you see the first application of Milliput to fill the opening and to fill imperfections and screw holes in the block.

 

 

 

In the photograph below you see how I used the steering box to continually ascertain the results of cutting and filing to obtain the new reasonably accurate location.

 

This photograph was taken in the early stages.

 

 

 

Below you see the modified mounting location in its present state.  The major remaining task is to build the bearing caps that will secure the steering box output shaft to the two pillars.  The pillars were built from three different sized styrene rods welded together.

 

The photographs below also shows the first test fitting of a water pipe kit from Model Motorcars.  In addition to the usual chore of cleaning up the Pocher component part, I drilled a hole in the water pump and enlarged the two holes in the block. 

 

Lots of Milliput sanding dust.

 

 

 

 

 

More evidence of the work required to create the illusion that the engine is not from a Pocher kit.

 

 

 

The Pocher "spark plugs" are just small hollow cylinders.  You can see them in earlier photographs.

 

I will replace them with components from Model Motorcars.  To prepare for the installation, you must remove the Pocher "plugs",  grind the mounting positions flat, and drill holes in the head.  Accomplishing this in a tight narrow space is a bit of a challenge.

 

You can see one Model Motorcar plug placed loosely in its position.  After painting the head and the plug's "porcelain",  MMC recommends that the plugs be melted into position with a soldering iron.

 

 

 

Interestingly, the holes you drill emerge in the proper location of the combustion chambers(!).

 

The lack of intake and exhaust valves limits power just a bit.

 

[Codger]

I'm back to scrutinize, criticize and drool............... Yes, noting you do looks what Pocher threw at us.

Also happy to see you  actually make plastic dust like we mere mortals.

Suggest you paint the porcelains after melting in  - there I go being a busy-body.

[Endeavor]

5 hours ago, Codger said:

 

Suggest you paint the porcelains after melting in  - there I go being a busy-body.

Yes!  I wondered both about the instruction to "melt" the plugs into position and to do it after painting.

 

"busy body"?  Never!

[Endeavor]

Rather than "melt" the plugs into the head per MMC's instructions, I drilled just the tops of the holes a bit larger so the plugs fit flush.

 

I won't have to worry about either melting the soon to be applied white paint or applying the paint in such a tight space.

 

 

The photographs below show the carburetor, blower, and intake manifolds placed loosely on the engine.  It took considerable work on these parts to get to this point.

 

My kit was manufactured when the factory molds were worn, so hours were spent filling, cutting, sanding, and filing all of these parts to repair the resulting defects and imperfections.

 

Pegs were fitted to the blower and the mounting holes were enlarged to fit the pegs and to move the location of the assembly back a bit, both to eliminate the gap between the blower and the blower drive and to make the blower align properly with the intake manifolds.

 

The intake manifolds were separated and holes drilled for the bolts that will attach them to the blower.  The molded in blow-off valves were removed and holes drilled for the scratched replacements.

 

 

 

 

 

 

 

 

Below you see the styrene pegs installed in the back of the blower and the enlarged mounting holes in the block.  All of the engine accessories and components will be installed using pegs, rather than being attached from inside the block with screws as Pocher intended.

 

The generator has a brass bolt installed.  This photograph illustrates one of the challenges of detailing these kits.  The bolt head is too wide - 2mm- and too tall.

 

 

 

Another look at part of the blower and a look at the wire  that will be will be wound around the brad.

 

[Codger]

A staggering amount of professional work to get a prepped and correct Alfa 8C engine. It looks to far exceed a MFH intense project which all require extensive parts prep. You've done both so am I correct?

 

Confession; although I've seen many beautifully assembled Pocher Alfas before, I'm ruined to ever accept a kit-built engine after this one - even one with added detail- again.

 

[Endeavor]

23 hours ago, Codger said:

A staggering amount of professional work to get a prepped and correct Alfa 8C engine. It looks to far exceed a MFH intense project which all require extensive parts prep. You've done both so am I correct?

 

Confession; although I've seen many beautifully assembled Pocher Alfas before, I'm ruined to ever accept a kit-built engine after this one - even one with added detail- again.

 

Thanks, as always, for your generous comments.  The engine will not have the superb details of the Alfa engines produced by builders like JoNZ, but I hope that it will be a reasonable representation of the prototypes.

 

I have built one MFH kit, the 1/12th scale Alfetta Tipo 159M.  Almost all of the metal parts required considerable work - drilling holes, removing mold lines, and small adjustments - but after each part was prepared to MFH’s specs, it fit perfectly and matched its prototype component.  The MFH kit does not require re-shaping parts, scratch building, or third party parts.

 

You are correct.  Pocher parts are much more challenging because, too often, they have manufacturing defects and/or the design does not match the prototype parts.  Rather than build to Pocher specs, the builder must modify components both to fit properly and to more closely resemble the prototypes.  Deviating from Pocher’s specs, scratch building, or third party parts are necessary.

[kpnuts]

Superb work again.

[Pouln]

Great stuff, you are doing here.

Are you going to modify the steering box itself?

From the pictures on Paul’s CD I took that the side has holes instead of the molded rivets (at least it looks like rivets to me).