Jump to content
Model Cars Magazine Forum

some old racing engines


Recommended Posts

momentary distraction

or just a break fr the Delage ...

Michael Portaro - aka Indycals - has a shapeways page with his 3D printed parts

including a kits of parts for the Merit Alfa 158

Michael has some issues with the new shapeways pricing policies - but we'll leave this issue aside for the moment

the kit is intended to build the Merit Alfa kit without major structural change to the kit - and the 3D grill is awesome


the parts look great - but the engine block was designed to fit like the kit block and use the kit exhaust pipe

problem is - the engine block on the Merit kit was about four scale inches too long  -  why ??  -  who knows

this was the first attempt to  produce a detailed 1/24th kit of Grand Prix car  - and the design is nearly sixty years old - so I guess no one complained  .. 




Link to comment
Share on other sites

So the idea is to modify the 3D parts to something that has the correct length -

which will eventually make for a better fit in the Merit kit body - once I fix the frame ......

and the 3D parts have a much more accurate shape than the Merit block - which was basically   -   a block ...

so I started by sawing off the valve gear casing at the front

then I sawed about 4 1/2 scale inches off the engine block

which left me with a straight seven engine block - suppose I could build it like that

but just in case some judge decides to count the spark plugs or exhaust pipes  (maybe 30% chance?)

I  removed the spark plug and exhaust port detail - which I will replace ...




Edited by absmiami
Link to comment
Share on other sites

Have you considered contacting Michael to see if he is willing to add your scale choice to his Shapeways listing??  Some Shapeways shop owners do this on a private request basis.

Link to comment
Share on other sites

Thanks for the heads-up on the engine, etc. I have a couple of the Merit kits I want to go whole hog on.

Interesting side note: not many years back, Revell made what should have been two identical engines, the 6.0 Hemi in the '09 Challenger and the Magnum kits, quite a bit different in overall length...and I guess no one complained.  :D

Link to comment
Share on other sites

some more photos of weekend progress

the engine will now sit in the engine bay of the Merit Alfa without the distributors jammed under the radiator  tank

the exhaust ports are gone  -  the new openings are drilled and await square flanges ....





Link to comment
Share on other sites

had to drill eight spark plug holes into the cyl head - and I will have to add a bunch of bolt holes and openings for the radiator pipes

the intake manifold is a very nice casting - but it is too long - matching the block's length

so that got sawed up, re-glued - and then placed into a new peg hole

it sits just above the superchargers - got to move them too - they sit farther back on the side of the engine block 

- the unit actually juts out past then end of the block

the superchargers are a nice example of how 3D printing can give you a complex part that would take weeks to scratchbuild

might add a some bolt details - we'll see  ....






Link to comment
Share on other sites

the printed parts had pegs that matched the kit mounting points on the kit frame

one small problem

the kit frame is all wrong ...

I've got enough drawings and literature to be certain that the frame rails ran straight back

- like a ladder   -   yes, it was referred to as a ladder frame ...

and were only 16 MM - in scale - apart   -   a very narrow - and simple - frame

the round chassis tubes visible on the 159 were not used on the 158

you can also refer to a building blog for the 12th scale MFH - they got all of these details correct

so on the back side of the gear case cover you can see 2 things

thing 1 - Portaro gets the basic shape of the block and cyl head right

thing 2 - I've begun to modify the frame mounts by removing that section from the printed parts

and re-shaping the 3D material and adding evergreen for the mounts - front and back

so whenever I get around to  1.  grinding out the kit frame,     and 2.   making the new frame

- from Evergreen stock - no big deal -

the engine will slip right on to the frame and should be securely mounted ...




Link to comment
Share on other sites

one brief note for Merit kit owners

the kit engine has a single supercharger - which is accurate for the early 158's

the Indycals engine kit duplicates the two stage supercharger on the 1950 Fangio car

the intake horn points forward and down - this is correct for the Fangio car

the later 158s and 159s had the intake horn that turned up and drew its air from the behind and above the engine bay

so even GP cars from the early fifties were evolving and changing within the racing season

this is not a recent development !! 

Link to comment
Share on other sites

the cylinder head 

marked the valve cover bolt holes with an xacto and a caliper

measure, divide, and drill  -  I'll add some RB Motion dome-head nuts - the smallest ones

then sanded a slight "crown" to the cyl head

the black is just a sharpie to help me with the marking and measuring 

 - actually you could "paint"the valve cover w a sharpie finish 

most of the engine will be flat black anyway ...




Link to comment
Share on other sites

all of that great cyl head detail that was drawn and printed into the top of the cyl head was removed to shorten the engine

so I then had to replace it with some bits and pieces of Evergreen plastic

the engine actually had a two piece cyl head - two blocks of four cylinders - bolted together in the middle

that's what the part is in 0790 - representing the tabs at the center of the cylinder head that are bolted together ...







Link to comment
Share on other sites

in case you've never opened a Merit kit box ...

by the way - the art work on the original kit boxes was great ...

0793 is shot of the kit engine sitting on the kit frame with the new and improved engine besides

quite a difference in scale block length vs the Merit engineer's guess ....





Link to comment
Share on other sites

some test fitting

want to make sure that the engine with the carb and intake horn will clear the bonnet

its close but looks OK

a profile photo of the real car looks like this ...

about the intake manifold though ....




Link to comment
Share on other sites

as I was adding some detail to the Weber Carb I recalled that Indycals' instructions warned that there might be some interference with the intake manifold once the supercharger and carb were attached

yup, there is ....

not a big deal  - removed some material from the back one third of the manifold and on goes the supercharger and weber carb ......






Link to comment
Share on other sites

don't try this at home - no just kidding

Do try this at home ...

the plug wires run through a really neat guide that is drilled with plug holes and openings for  (?) heat dissipation

like swiss cheese

this would be a bear to machine - like the supercharger - would take hours to do well

so I appreciate the 3D printed part - which is very accurate

but can we open and drill it for the wires ??

turns out that we can - the material is translucent - so you can see where the twist drills are going

but the material is also tough and just a little flexible

so if you go slow and use progressively smaller and larger drills, you can actually open the part

which is pretty cool ....



Link to comment
Share on other sites

Road and Track mag used to be really good

Really ! 

they would sometimes publish drawings fr artists that would show us stuff that we could not otherwise figure out

- like what does the bottom of the engine bay on an Alfa 158 look like ??  this is a scan of a section of a full page layout

the sheets of evergreen plastic come in handy every third blue moon ...

the correct size "metal siding" sheet - railroaders would use it to make an HO scale metal roof ...

was scribed w/a Tamiya scribing tool to open and deepen the grooves ...

presto - one finned engine sump base

-  with a couple of round oil filter covers punched from sheet plastic ...

will be epoxied to the bottom of the block after finishing more stuff  ...








Link to comment
Share on other sites

jammed a piece of evergreen strip into the cylinder head

when its time to fit plug boots and radiator pipes into the cylinder head - the extra material will keep everything in position

than sawed the gear case in half and added some bits and pieces of evergreen to detail the front and back of the cyl head

now need to make two pumps that sit down low in the front of the gear case - one - or both - not sure - are oil pumps - one might be a filter ...

haven't quite figured this all out yet

oil lines go in and out of a tank in the scuttle and in and out of a small radiator sitting under the water radiator

and then through a pump and then in and out of the engine block

so if anyone would like to send me the MFH  instructions for the 1/12th 158 kit - the pages showing the oil lines  -  that would be nice  .....






Link to comment
Share on other sites

  • 2 weeks later...

this week's lab experiment .....

the supercharger has a ring of small bolts lining the end cap facing forward

in scale they can't be much larger than - what? - 3/8 inch ?

to attempt to duplicate this ring of bolts I removed the smallest photo-etched bolts from this

Tuner Model Manufactory sheet ...

 I picked them off of the backing with a hobby knife and coaxed them into a film container cap

can't use a  tweezers - these parts  are too small

the pens that I buy for my office - Pentel - have these neat little protective nibs on the pen tips

took one off and glued it on to the end of a tooth pick - it's just a little bit sticky ...

this tool can pick up the dots - just a little surface pressure will hold the dot to the "tool" to transfer it to the surface of the part, which I coated with some clear acrylic paint for an adhesive

once the dot is on the part you can move it around and locate it with the end of a hobby knife

now I'll paint the part - which will hopefully secure the "bolt" detail ...

we'll see ... 





Link to comment
Share on other sites

  • 4 weeks later...

time to make and/or correct some pumps at the front of the engine - using the usual suspects - evergreen plastic rods and stock - and a length of .040 brass tube

cutting and drilling etc

the scroll shaped pump is part of the cooling system - haven't yet figured out where everything runs ....





Link to comment
Share on other sites

also had to make changes to this portion of the 3-D casting to locate what appears to be a pump and filter on the photo-right side of the casing

the MFH 158 and 9 engine kits get this right - so I am referencing a couple of building blogs of these kits for help  - getting as much of this cone as possible before gluing this portion of the gear casing back to the engine block - as I had done with the cylinder head





Link to comment
Share on other sites

almost done - but the pumps are in place for the photo - but not attached

will paint these separately - pondering whether to drill the dimpled holes and glue in some tiny bolts or bolt-head detail - I might - because the bottom of the engine  will be visible through the sump opening








Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Create New...