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Macchi M-5


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Hi all,
The rear edge of the cockpit rim was fitted with shoulder padding which is not in the kit.
I represented this padding using 'Milliput' putty. Once it has fully cured I'll clean it up. 

The photo-etch supplied with the kit has part 19, which is intended to represent a curved support for the top of the pilot’s seat, although I could not find any references to this type of seat support.
However photographs do show a fixture connecting the top, rear edge of the seat to the rear bulkhead of the cockpit.
I represented this fixing using 0.5 plastic rod. 

The inlet and exhaust valves on the 'Isotta Fraschini' V4B engine are operated by an overhead shaft.
The kit shaft is moulded as one shaft. The actual engine had three separate shafts.
Also the shaft mounting to the engine do not align.
I'll correct by cutting away the mountings from the shaft then drill out the three segments and insert brass tubes.

 

Mike


seatfixing.jpg

 

shaftgaps.jpg

 

camshaftalignment.jpg

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Hi all,
The valve operation on the 'Isotta Fraschini' V4B engine is strange by comparison to other in-line engines of the period. 
Normally the inlet and exhaust valves on each cylinder would be operated from a single overhead 'camshaft'.
However photographs and drawing for this engine show three separate shafts, each operating the valves for its cylinder bank.
I can only assume the drive for the three shafts is located below them in the lower half of the overall housing, which is not represented on the kit part.
The kit part, including the inlet manifolds seems to have been modelled more on that fitted, for example, on the Daimler-Mercedes in-line engines.

 

operatingshaft2.jpg

 

I've modified the overhead operating shaft by cutting it into the three sections, removing the kit shaft and replacing it with 1.8 mm diameter tubing.
This required some re-profiling of the operating shaft mountings at each end of the engine (radiator and propeller shaft ends), including 2 mm extension to fit to the end vertical drives.
The tubes still need to be blocked at each end as the shafts were solid, not tubular.

 

operatingshaft5.jpg
 
This has also shown up several other areas of the engine that require attention (so far):
Both inlet manifolds and the two carburettors are incorrectly moulded - the manifolds too long and wrong shape - the carburettors are joined, but in fact were separately located.
No spark plugs location.
No water pump supplied in the kit.

 

Mike 

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Hi all,
The radiator assembly done.
This needs to be done now and added into the radiator housing and engine bottom fairing.
Then I can start to work on the missing components at the forward end of the engine, such as magnetos, pipes etc,

 

Mike

 

radassembly.jpg

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Hi all,
Work continues on modifying the kit engine to represent what the engine actually looked like.
I've now added a 'camshaft' below the 3 vale lever shafts from 1.8 mm diameter tube.
Also added a pair of 'Taurus' magnetos and a drive shaft (from the spares box).
Finally the drive at the rear end of the engine (1.0 mm tube and drive head modified from spares).

 

It's all a bit rough at the moment and I still need to add water pump and if possible and oil pump, plus their associated pipes (where possible).

Also the ignition lead support tube etc.

 

Mike

 

engbuild1.jpg

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Hi all,
The engine was fitted with a water pump for the cooling system.
On the actual engine the pump was located forward (radiator end) of the engine, below the magnetos and engine sump/crank case joint.
I wanted to represent the water pump and its pipe work, but due to space restrictions, I had to locate it higher on the engine than was actually the case.
 
The kit engine has a pronounced 'step' in the engine sump at the end facing the radiator (forward end). This 'step' is intended to fit under the installed radiator.
I've cut away this 'step' and fitted two propeller shaft housings from my spares box to recreate the previously rounded end of the sump.
To one side I've added a modified water pump, again from my spares box. 

 

Still more to do - plugs and wiring, ignition lead support tubes, oil filler pipes and what pipe work and controls I can fit.
The whole assembly still needs cleaning up and painting of course.

 

Mike

 

waterpump.jpg

 

waterpumpfit.jpg

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Hi all,
On each side of the engine are flat section tubes that are attached at the bottom of the cylinder heads.
These tubes retain and support the six ignition leads on each side of the engine.
The kit supplies photo-etch parts which need to be bent to represent the two support tubes. 
However, when created, these photo-etch tubes are much larger than shown in the photographs.
Also, once bent over, they create a flat, double thick 'plate' rather than a flat section tube.
Therefore I decided to create the two support tubes using micro-tube.

Two brass tubes of 1.6 mm diameter, annealed to soften them then semi-flattened in smooth jaw vice.
The ends were filed to a 60 degree angle then two holes of 0.5 mm diameter drilled into the inboard sides.
Brass pins of 0.5 mm diameter were secured in these holes and corresponding location holes drilled into the base of the cylinder banks.


Mike

 

ignleadtube1.jpg

 

supporttubesdone.jpg

Edited by Sandbagger
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Hi all,
I believe the cooling system operates as follows:

A coolant pipe is attached to one side of the engine. The pipe connects each of the three cylinder banks.
Coolant is drawn through a pipe from the bottom of the radiator by the pump.
The pump then supplies coolant through the engine pipe into the cylinder cooling jackets.

 

coolantpipe1.jpg

 

The coolant passes up inside the cooling jackets and out through cylinder connectors to a return pipe on the opposite, top side of the engine.
From there the coolant flows back to the radiator to be cooled. 

 

tube2.jpg

 

I created the pump to cylinder feed pipe using 0.9 mm tube with 1.1 mm diameter collars. The flexible pipe to the pump is 0.8 mm diameter lead wire.
The larger return pipe is 1.4 mm diameter tube with six 0.8 mm holes drilled into one side to align with the six 90 degree pipe connectors, made from annealed and bent 0.8 mm tube.
Holes of 0.8 mm diameter were drilled vertically down into the engine lugs at one side of the valves on that side of the engine.
The connectors were then located into the engine and return pipe,

 

Mike 

 

coolantpipedone.jpg

 

coolantpipedone2.jpg

 

coolantpipedone3.jpg

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Hi all,
The kit supplied engine carburettors and their intake manifolds are not correct for this engine and need to be drastically modified to make them represent the actual engine.
The photographs below is one of several that show what the fuel supply components on the engine actually looked like, which is not how the kit engine parts are made.
    
carburettors3.jpg

 

Basically:
The two carburettors need to be separated.
The two carburettors need air intake openings.    
The two inlet manifold pipes need to be modified.

 

The vertical drop pipes were cut away from the three ported header pipes.
The three ported header pipes were cut and extended using a 0.5 mm diameter pin, so that the three ports aligned correctly with the cylinder heads.
The vertical drop pipes were shortened and had a 0.5 mm diameter pin inserted in the tops, which were inserted into a hole drilled in the underside of the extended three ported header pipes.
This was done to correctly align the drop pipes to between the cylinder banks.
The joined kit carburettors were separated and each attached to the bottom of the drop pipes with 0.5 mm pin.
Finally the 90 degree bend that was cut away from the drop pipes were used to create the air intakes under the carburettors.    

 

There's a way to go on each of the two assemblies, such as filling and sanding and the addition of the interconnected fuel supply pipes and throttle controls etc.
Those components will have to be scratched,

 

Mike 

 

carburettors4.jpg

 

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Hi all,
I thought I'd explain why I'm attempting to detail the engine as much as I am.
Normally if the engine is partly or totally covered by airframe or engine panels, there would be less reason to detail the engine as much.
However the Macchi M.5, even with the engine under tray and side panels fitted, was mostly visible.
The particular aircraft I'm attempting to model is 'FRANGAR NON FLECTAR’, Serial No.7288 as flown by Tenente DV Alberto Bartolozzo, Officer Commanding No.260a Squadriglla, operating from Venice during 1918.
That particular aircraft did not have the engine side panels fitted and so the entire engine was fully exposed.
The engine is a primary focal point for anyone looking at the model.
Therefore I felt that it was important to rectify the apparent omissions and errors with the kit supplied engine.

 

Mike

 

photo1plus.jpg

 

nocowl.jpg  

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Hi all,
On the side of the engine crank case and between the two carburettors is a blanking plate.
I believe this plate was fitted to seal what was previously the oil filler pipe for the engine sump, but not used on this version of the engine. 

 

To represent this blanking plate, I cut a disc of approximately 2.5 mm diameter from 0.2 mm thick plastic card and secure it in position on the sump using thin CA adhesive.

 

blankingplate.jpg

 

oldfiller.jpg

 

blankingplate2.jpg

 

Two oil filler pipes were used to replenish oil in the engine sump and were located on the engine crank case on the opposite side from the carburettors. Each was fitted with a cap.   

Two 2.5 mm diameter discs were cut from 0.2 mm plastic card and secured on the sump.
The centre of each disc and into the sump were gradually drilled up to 1.3 mm diameter.
To represent these filler pipes, 0.8 mm diameter rod was slide into 1.2 mm tube. The tubes were annealed then bent to the required angle.
One end was roll cut to remove the outer tube leaving rod exposed. The other end was cut completely through.
2.0 mm plastic rod was cut to to create two 5 mm lengths and a 0.9 mm diameter hole drilled through the centre of each.
These were attached on the exposed 0.8 mm rods and secured with CA adhesive.
The top of the 'caps' were then filed down to a height of 1.5 mm and sanded around the top edge..
Lastly the two 'filler pipes' were secured in the crank case holes with CA adhesive,

 

Mike

 

oilfilltubes.jpg

 

fillerpipes2.jpg

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Hi all,
A few more updates for the carburettors and induction manifolds.
Hollowed out the air intakes at the bottom of the carburettors.
The induction manifolds cut/joins have been filled.
Added the carburettor barrels (made from a tooth pick).
Added 0.5 mm diameter plastic rod into the induction manifolds and carburettor barrels to represent the interconnecting fuel supply pipe and auxiliary pipe.
Added control lever for the throttle butterfly valves in the induction manifolds (control rods to added later).
Added three nuts to each intake manifold header pipe.

 

Obviously it all needs cleaning up and priming, but for now I'll move onto creating the 12 spark plugs,

 

Mike

 

carburettors3.jpg

 

carburettors6plus.jpg

 

Edited by Sandbagger
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Hi all,
Twelve spark plugs with ignition leads.
Made from 0.5 mm diameter tube with 0.28 mm diameter copper wire (annealed) leads.
Fitted into 0.6 mm diameter holes drilled into both sides of each cylinder bank.

 

Now it's onto the really tricky valve operating gear,

 

Mike

 

plugsleads.jpg

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Hi all,
I've been working the last few days on ways to better represent the valve operating gear for this engine, as the kit supplied photo-etch is not very realistic.
After trying converted photo-etch, card and other methods, I decided to go with this.
This is not meant to accurately 'reproduce' the engines valve gear, but more to 'represent' it as the kit engine does not lend itself easily to this modification.

The operating levers are made as two separate levers from 0.5 mm thick plastic card.
The levers are shaped then joined at the centre and secured to their individual operating shafts.
The bottom of the push rods were marked on the engine then drilled with a 0.6 mm diameter drill.
Nickel-Silver rod of 0.4 mm diameter was cut and secured in each drilled hole and against the end of the levers.
Finally a 0.51 mm hexagonal nut (from 'RB Motions' was added to the top of each rod.

 

Once all of the push rods are done I need to add the pivot lever between each pair of rods.
  
Mike

 

valvegear1.jpg

 

valvegear6.jpg

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Hi all,
Just a quick update for the engine modifications.
The valve operating gear is now done - made from 0.2 mm and 0.5 mm thick plastic card..
The shots below show the dry fit of:

 

Carburettor and induction manifolds
Ignition lead support tubes
Coolant supply and return pipes.

 

All that's left now are a couple of external oil pipes and it should be ready to start painting and building the engine.
Other items such as ignition leads, engine placard plates etc can't be added until the engine build is completed,

 

Mike

 

engdryfit1.jpg

 

engdryfit2.jpg

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Hi all,
Two pipes were connected to the underside of the coolant return pipe, located at the top of the engine.
The two pipes were routed across to the other side of the engine, between the end and centre cylinder banks.
The purpose for  these two pipes is not clear or to where on the engine they were eventually connected.
As the pipes were connected to the coolant return pipe, it would seem hot coolant from the engine was carried in the pipes.
My only assumption is that these pipes supplied hot coolant to the housings of the two carburettors, thereby ’pre-heating’ both of the carburettors.
This would have helped preventing icing up, which may have been more of a problem for seaplanes more than land based aircraft.  

 

The pipes were made from 0.8 mm and 0.5 mm diameter tube.

 

Mike

 

addpipe7.jpg

 

preheat1.jpg

 

preheat2.jpg

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Hi all,
I've gone as far as I can modifying the resin kit engine to better resemble the actual 'Isotta Fraschini V4B’ engine.
The shots below show it primed and dry fitted, including replacement exhaust pipes made from 1.4 mm diameter tube. 
It's the longest engine modification I've undertaken thus far, but hopefully it'll be worth it.

 

So now, it's time to move onto modifying the cockpit area !!

 

Mike

 

primedeng1.jpg

 

primedeng2.jpg

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Thanks guys - this engine has taken me the longest of all to modify to better represent the real engine.

The resin kit is generally of good quality but let down in some areas, such as the engine.

Not to worry - we are modellers not assemblers, so onwards and upwards,

 

Mike

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