forum.ww1aircraftmodels.com
WW1 Aircraft Modeling => Under Construction => Topic started by: uncletony on February 01, 2025, 11:58:10 AM
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While there are still several parts left to design and put into production before these sets are released, things are far enough along to do some test builds with the aim to wrinkle out any fit issues and illuminate the gotchas and snakes in the grass. I am doing two builds at the moment, more or less simultaneously; an unpainted "go fast and break things" build and a slower, fully painted build that will hopefully benefit from insights gained from the former. For these builds I am leaving out the complexities of the internal parts, but I will return to those items soon enough.
Here are the rafts that make up the "short block."
(https://i.imgur.com/UOScD7J.jpg)
Not shown is the crankshaft ; one of those things left to decide as to what form it will take in the basic model, what it will be made of, etc.
(https://i.imgur.com/zZp4zSN.jpg)
Main crankcase studs are 11.5mm x .5mm brass rod (or tube, as shown here).
(https://i.imgur.com/edWSasC.jpg)
This is a test print of the small parts used to assemble the short block. (I need to provide more of the hose clamps as ten are exactly what are required. Also missing are small bolts for the front and rear cylinder bases.)
(https://i.imgur.com/OlNunuO.jpg)
Cylinders are affixed with the characteristic clamp and nut, first chased with a .55mm bit.
(https://i.imgur.com/1BjqStZ.jpg)
(https://i.imgur.com/a0BVs6T.jpg)
(https://i.imgur.com/5ir9w3v.jpg)
This part of the build went together easily enough with no huge surprises, but lots of little things noted that can be improved as this lurches towards production.
(https://i.imgur.com/qGJN53a.jpg)
(https://i.imgur.com/AiElQOB.jpg)
Satisfied with the basic fit and proof of concept, construction commences on a second, painted version. Not a lot of extra commentary needed.
(https://i.imgur.com/1X8FuPw.jpg)
(https://i.imgur.com/4fMR4HH.jpg)
(https://i.imgur.com/nGwUgoB.jpg)
(https://i.imgur.com/yv62vGF.jpg)
(https://i.imgur.com/PRdgjjX.jpg)
(https://i.imgur.com/EA5L4gr.jpg)
(https://i.imgur.com/Bh6C0YA.jpg)
Next up: assembling the magnetos and ignition wiring.
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Hi Bo,
This looks very interesting and of high quality,
Mike
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Can't wait...... :)
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The Master returns!
Good to see you, Bo and good to see your creations.
Cheers,
Bob ;)
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Bo, that's completely crazy. Totally insane - love it! ;D
Servua
Bertl
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Absolutely spectacular!
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Im almost waiting for you to fill it with oil and fuel - so detailed! ;D
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Oh my goodness, what a work of art!
Really looking forward to see this progress further.
Amazing stuff.
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Thanks guys...
In this installment I'll assemble & add the Bosch ZH6 magnetos along with the ignition wiring harnesses. I'll need one part from the cam drive tower raft as well.
(https://i.imgur.com/6O8GDVH.jpg)
The first step is adding the base of the cam drive tower to the rear of the crankcase. This housing held the gears that drive the two magnetos.
(https://i.imgur.com/CVQzR2w.jpg)
Each magneto is made of three parts -- body, magnet, and cap.
(https://i.imgur.com/4w0hJAg.jpg)
Assembly is simple. The cap and magnet can be secured with a drop of runny CA or even watered down Future.
(https://i.imgur.com/AgD1RAn.jpg)
Note that the magnetos are not identical left to right; the advance linkages are different and the right hand M1 magneto has 7 leads on the cap (i.e. one in the center, for the starting magneto). I managed to get this mixed up on this first "greybox" test build.
(https://i.imgur.com/bO2yjIrl.jpg)
The magneto is secured to the crankcase with a dot of epoxy at its base, and then finished with the hold down strap which is secured with watered down Future.
(https://i.imgur.com/MWzDXoU.jpg)
(https://i.imgur.com/lDowASw.jpg)
Now onto the wiring harnesses. They are printed from a custom blend of resin that gives them good flexibility while retaining detail.
(https://i.imgur.com/c1gxUOq.jpg)
Successfully removing the harnesses from their rafts is not especially difficult but patience is required and a certain technique helps. First remove all of the posts supporting the sparkplugs and bakelite tube. Always snip first as close as possible to the work part and then remove the post at the raft -- doing so in this order avoids driving the post into the part and potentially breaking something.
(https://i.imgur.com/BQXzqPG.jpg)
At this point you can tease the individual spark plug wires off their u-shaped supports using sharp tweezers. Work from top (#1 cylinder) to bottom (#6 cylinder, nearest the magnetos.)
(https://i.imgur.com/QrVtup2.jpg)
Resist the temptation to chop down the u-shaped supports even after the wires are freed! Doing so risks the danger of propelling them into the wires right where they are most vulnerable.
(https://i.imgur.com/NHEyPpA.jpg)
After a little cleanup, assembly is straight forward. Note that the pins on the magneto cap connections need to be trimmed back to almost -- not quite -- flush with the back of the wiring bundle to achieve a good fit. Leave, say, .1mm or so. Spark plugs simply insert into their respective holes in the cylinders; a dot of watered down Future will hold them in place.
(https://i.imgur.com/E8TJGuf.jpg)
(https://i.imgur.com/1wvz3v0.jpg)
Painted version again moves ahead without any big surprises...
(https://i.imgur.com/fFvpebJ.jpg)
(https://i.imgur.com/pnLnHiL.jpg)
(https://i.imgur.com/LCYclXF.jpg)
Next up: valve train and rocker gear...
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OMG! 😶
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Time to assemble the valve train, comprising the rocker boxes, valve springs, rocker arms and camshaft.
(https://i.imgur.com/fDcK6wu.jpg)
Here are the rafts, including the camshaft (still in development when this was taken) and the already-seen cam tower raft (as it turns out, unused in this sequence.)
(https://i.imgur.com/ytuilOJ.jpg)
The camshaft is required, as the lobes determine the valve spring compression. The rocker boxes are assembled by sliding them over the camshaft. I should note that in this preproduction greybox build, these are not the final versions of the rocker boxes either. As shown I have drilled out the bosses where they mate to the cylinder head studs; this is not necessary with the production parts.
(https://i.imgur.com/6jvspPi.jpg)
The rocker boxes are not glued up at this stage, just dry fitted.
(https://i.imgur.com/NEy1sId.jpg)
Instead, the rocker boxes are glued to the studs on the tops of the cylinders, one at a time, starting with the rearmost. I used epoxy on the rear rocker box to give me time to jiggle it into alignment. The remaining boxes were secured with CA.
(https://i.imgur.com/AUws0xO.jpg)
(https://i.imgur.com/3Uxev0b.jpg)
The valve springs come on rafts like this. Obviously a little bit of care is required to remove them, but it's not terrible.
(https://i.imgur.com/z7c9O8n.jpg)
(https://i.imgur.com/2Tc4V1B.jpg)
The springs are simply inserted into the valve guides. It's important to chase the valve guides with a .35mm drill bit beforehand. Preferably this step should be performed before assembling the cylinders. With the valve guides properly cleared, the valve springs easily do their thing and bounce up and down.
(https://i.imgur.com/scs3WV1.jpg)
(https://i.imgur.com/gR7NFz0.jpg)
The rocker arms are assembled with the followers on the cams so that they are correctly open or closed depending on the rotation of the camshaft. It took me awhile to perfect the technique for this process. In the end, I found that securing the rocker in its trough with a drop of watered down future worked best. Also note that in this test build I was experimenting with resins for the rocker arms. This white stuff is very strong but prints a little on the rough side. I discovered that the rocker arms aren't as delicate as I feared and therefore could be printed with the really high fidelity stuff.
(https://i.imgur.com/nlIQpIU.jpg)
The rocker box cover then just drops in place. These are pre-production parts; the production version has pins for the cover.
(https://i.imgur.com/VLjO3WN.jpg)
The whole thing assembled...
(https://i.imgur.com/HIEyblt.jpg)
On to the painted version, for which I used the final production parts.
(https://i.imgur.com/NL1uJbR.jpg)
Here you can see the pins for the rocker covers.
(https://i.imgur.com/UZATt3X.jpg)
Here are the production rocker arms rendered in high fidelity resin. I didn't break any assembling this thing; the real danger is mistakenly cutting away the wrong elements when removing them from the raft. I'll try to make it very clear in the instructions what's sprue and what's actual workpiece. Again, the technique I found that worked best was to cement the rocker shaft in its trough with watered down future and holding it in place until it sets up enough to resist the valve spring. I decided to paint the rocker arms after assembly, a decision I'm not sure I'd repeat...
(https://i.imgur.com/Aik8H0t.jpg)
(https://i.imgur.com/kMgQkMm.jpg)
(https://i.imgur.com/JCQr8j4.jpg)
(https://i.imgur.com/4NsTaoP.jpg)
Here's a lurid close-up; not bad imo for 1/32 scale...
That's it for now. Next time I'll get the cam drive tower assembled along with various ancillaries.
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Absolutely stunning what 3D print tech can now allow us... Fantastic job, Bo!
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Thanks for that Przemo :)
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Unbelievable.
And all "only" in 1/32.
The zoomed-in pictures give you no idea how small some of the movable parts actually are.
Starting with the wafer-thin valve springs, the complete engine is an absolute masterpiece.
I wouldn't be surprised if the valves in the cylinder head could be operated ..... .
I've written about it before Bo - crazy, totally crazy .... but in a positive sense.
Servus
Bertl
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This is Way Above My skill Level and Pay Grade! I am absolutely stunned and amazed at your work in designing, printing, and assembling this Masterpiece!
RAGIII
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Just incredible!
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This is just nuts! I can't imagine the knowledge, skill and time required to CAD this all out. Stunning result.
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I just hope I have the skills to build this.....
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Starting over from the top, with production parts. Lower end first.
(https://i.imgur.com/kkDYwchl.jpg)
(https://i.imgur.com/EfVZvXQl.jpg)
(https://i.imgur.com/FqNy33Fl.jpg)
(https://i.imgur.com/QhEG7abl.jpg)
(https://i.imgur.com/9lMQt3xl.jpg)
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Pistons assembled to connecting rods...
(https://i.imgur.com/31lFu2nl.jpg)
(https://i.imgur.com/njItQiVl.jpg)
(https://i.imgur.com/C3vtkSKl.jpg)
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Absolutely spectacular!
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Thanks Przemo!
A few more for today, as I work on closing up the crankcase...
(https://i.imgur.com/tyFZfWkl.jpg)
(https://i.imgur.com/kAeCvKyl.jpg)
(https://i.imgur.com/N8hYz2Cl.jpg)
(https://i.imgur.com/G7tiW6jl.jpg)
(https://i.imgur.com/LpFGjuCl.jpg)
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Crazy details! I can appreciate the satisfaction of creating and assembling everything. It's a bit like painting and detailing things that you know won't be seen once the fuselage is closed up, only on a whole other level.
/Fredrik
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:o :o :o
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Wow! Just add gas and oil and it?s ready for ignition.
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I don't know if anyone noticed, but the crankcase interior is painted in
the characteristic yellowish oil stained aluminium colour.
Awesome work as always, must save up for one.
Regards, Pete in RI
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I don't know if anyone noticed, but the crankcase interior is painted in
the characteristic yellowish oil stained aluminium colour.
:)
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Small update, got the cylinders painted. They are painted with a mix of 50:50 Tamiya Neutral Gray/ German Grey, which is quite light in terms of value, but allows the subsequent dark wash to pick up the details. Exhaust flanges masked and sprayed with Alclad Aluminum.
(https://i.imgur.com/DvsS0iJ.jpg)
(https://i.imgur.com/ixpMLvv.jpg)
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I'm amazed and flabbergasted at the level of detail here.
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Thanks Gary...
I decided I wasn't completely happy with how the finish on the reciprocating parts came out, so I redid the pistons, con-rods and crankshaft. I think this result is a little better...
(https://i.imgur.com/rMABbHv.jpg)
(https://i.imgur.com/Hiaw7sb.jpg)
(https://i.imgur.com/DQBr0PG.jpg)
(https://i.imgur.com/MT6jna4h.jpg)
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This thread will be so useful when I build mine, thanks for sharing.
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Amazing. I have no words....
Did you have to go with standard size main bearings or scale 10thou over?.....
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Did you have to go with standard size main bearings or scale 10thou over?.....
;D
This thread will be so useful when I build mine, thanks for sharing.
I can give you a couple of tips for finishing the crankshaft and con rods, should you choose to use them.
The con rods have support connections on either side; this is unfortunate but unavoidable. The parts are small enough that holding them while touching them up with a sanding stick is difficult, at least for me with my fat fingers. I made a very simple holding tool from a block of styrene, with holes drilled to accept two short (~10mm) lengths of brass tubing, 1.6mm OD and .7mm OD respectively, and spaced per the conrod's big end and wrist pin spacing. I don't have a great photo of it but you can most of it in the lower right hand corner of this photo:
(https://i.imgur.com/e6qw7Yo.jpg)
This simple tool makes it MUCH easier to handle the conrods while prepping them for paint.
To hold the conrods while painting, I CA'ed a short length of 1.6mm OD to a round toothpick (aka "cocktail stick" to Brits, if I'm not mistaken). Slip the conrod over the brass tube until it is up against the toothpick. Secure with an even shorter length of 1.8mm OD (1.6mm ID) tube slipped over the first tube and snug against the conrod.
Similarly, I glued 1.8mm OD / 1.6mm ID lengths of tube to toothpicks to hold the crankshaft sections by the crank pin for handling and painting, first marking the toothpicks with stripes so that I could keep everything straight in terms of what goes where.
I primed the crankshaft parts and conrods with Alclad Black Micro-Filler primer before spraying with Alclad Chrome. I did not polish the black primed parts before spraying the chrome on, which may have been worthwhile. To the naked eye and even under magnification the metallic effect is pretty convincing; the macro lens however can be a cruel master.
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Thanks for the tips Bo. I had planned to use mine closed up in "special" builds but I can see I might be tempted to do a maintenance scene.........