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Old 07-20-2007, 02:36 PM
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Build: Up-Scale 1:20, Republic P-47D-25, Halinski 3/06

NOTE:This thread is an extract of my posts from the thread of the same name at the Zealot/CardModels.net site. I have grouped
them together more than they were originally where it makes sense, and edited a bit of extraneous text, in addition to using thumbnails
instead of full size pics. Some posts will still read a bit disjointed because of the time compression and lack of intervening posts
from other members of the other forum.



For my next project, I've opted to Up-scale a printed kit! I know that the vogue seems to be to build smaller, but I want to go the
other way and see what happens. So here I'm going to make a stab at building the Halinski P-47D-25 Thunderbolt upsized 65% to
approximately 1:20 scale.

I've wanted to tackle this kit as I really like the Jug, but it weighs in at around 1200 parts and I just could not see doing it at 1:33
scale. The Zero was bad enough! I think the level of detail of this kit will work out well at the larger scale, plus I'm tentatively
planning to add some extra detail where it makes sense (and is visible!), for example landing gear and wheel wells, etc. And I’ll
probably add some extra cockpit detail too as long as I can see it (No more totally gratuitous detail for me!).

As for why I picked 1:20 scale; if I'm going to do this, I wanted a big enough increase to make it worth doing. I toyed with the idea of
a double to 1:16 or so, but quickly realized that quite a few parts (skins mostly) would span more than 1 letter size sheet. One of my
criteria is to print at home to normal size paper, so the thought of joining a bunch of skin parts in the middle nixed that idea. Plus –
where in the world would I PUT such a monster! As it turns out, a 65% increase will cause me to only have to split one part - the main
wing skins - which have a pretty natural seam printed on them about midway out where I can make the joint.

For a rescale from a printed kit, there is a lot of preparation - particularly for an upscale. First there is scanning. I have been
looking at some old threads and in particular posts by Leif and Gil that have some good info for scanning and rescaling. So a big hat
tip to those guys because I'm stealing a lot of their info here!
The first thing I had to do was cut each page of the book roughly in half, weaving the cut among the parts, so that I end up with chunks
that fit on the scanner bed.

Scanning:

The important thing to know about scanning is to NOT allow the scanning software to assume you are scanning photos, or otherwise be
allowed to make "exposure" decisions. If you allow this, scans from one page to the next will not come out the same - will not match
color and darkness. My scanner (Epson) has a Document setting, and in addition I had to force it each time to turn OFF Auto Exposure,
even though I had picked Document.

One reality about scanning seems to be that the color and darkness you get from a scan and subsequent prints WILL NOT exactly match the
kit. Perhaps with really high-end equipment this may be possible, but with the type of stuff we have at home, my attempts seem to
indicate that you will frustrate yourself to insanity if you try. The important thing is to get consistency between the scans so things
match and to try to just get reasonably close on color. For this kit I really only had one noticeably bad result and that was with Reds.
This model has a red cowl and rudder, and these were coming out more dark, almost rust-colored. So for these parts only I rescanned that
page and allowed the software to do auto-exposure and they came out a good bit brighter. So I will just substitute those parts only.

About DPI (dots per inch). I was tempted to use higher DPI settings (like 720) to help bring out more of that fantasic Halinski printed
detail. I could, in fact, see differences in greatly magnified sections at higher DPI. But printed, not so much. And the file size
increase is HUGH! (doubling DPI quadrouples the number of pixels). Load/save/editing times dictate that you not go overboard on DPI!

To summarize, my settings for my Epson scanner are:

Type: Document
No Auto-Exposure
Arrange the input size to just fit each page fragment (using the crop box)
300 dpi
165% Size
Save to TIFF files (do NOT use JPEG!)

Editing:

As long as you get a good scan using a document setting, you might have the resulting files’ color pretty like you need them, but one
tip I got from reading the experienced guys' posts at this point was to ensure that your files have their “white point” adjusted – again
to help make sure that there is color consistency from one file to the next. The process here would vary in details from one editing
program to another. In Photoshop, you open up a file, select Image/Adjustments/Levels, click the Set White Point dropper, and click
somewhere in the “white” area between parts. If the page background is a little off-color, everything will be adjusted until that point
you clicked is white. In my experience scanning this model, there was rarely any difference made when I did this, as they were quite
close to white already.

One thing I did after setting the white point was to save the files as Photoshop PSD files. This made the files about half the size and
thus allows faster load/save times. You just want to make sure that at no time in the process you allow the files to be saved in any
lossy compression format (JPEG, etc)

The MAJOR task now is segregating parts. A lot of printed kits are printed on paper a good bit larger than our “letter” size (or even
European A4 size), plus the 65% increase obviously means that the resultant files are much larger than you can print with a typical home
printer! So, now you’ve got to split things up to fit on whatever you are printing to. The easy way would be to just get into your
editor and select letter size groups of parts and then cut and paste those into new files. Or even just print sections of each file
letting the parts get cropped at the margins. I decided that while I was going to all this trouble anyway, I’d segregate them into
assembly order – a big job! But I always get tired of hunting for parts so I thought I’d do the work on the front end. I’m not really
convinced it’s worth all the trouble. I’m not yet finished with it yet, but I’ve got enough pages made to get a long way into the
construction.

You need to at least segregate parts into categories by laminating thickness – all the “1mm” parts together, “0.5mm” parts together,
regular card stock parts on the rest, etc. This kit has 6 thickness categories to worry about (more on that later).

Printing:

On the printer side, you also want to make sure the printer driver is not making “exposure” decisions for you, so you’ll want to select
something for output that is NOT Photo. I’m printing on a Canon i860, and it has custom settings to print as type: Graphic. I also make
the Brightness setting = Light to more closely match the original book’s darkness.

Materials:

Upsizing the parts themselves is not the end of the battle. You also need to make sure your stock and laminating thicknesses are
multiplied as well. Some basic facts on current Halinski books:

Card pages are 0.21 mm thick (same as 65 lb Wausau Bright White)
Paper pages are 0.10 mm thick (about the same as 22 lb inkjet paper)

I have a pad of Strathmore Bristol, which measures 0.32 mm thick, a 52% increase over the Halinski card stock. Close enough I think for
upsizing the card stock parts. This stock is pretty stiff, and does not fold nearly as cleanly and easily as our regular weight card, so
I think for many small parts that will be rolled and folded, I’ll still print a 65lb stock version. The thicker Bristol will be used for
skins and parts that are basically flat, and any other things where dimensions might make a difference in fit.

As for paper parts, anything that’s just a pattern I’ll print to regular paper, but for those parts that get rolled around wire, etc, I
will probably try to upscale it to something like 28 lb paper.

As for laminations, 0.5 mm and 1 mm come out to 0.825 and 1.65 mm respectively. I’ve got a stock of ~.80 mm cardboard from the back of
X-ray films (hat tip to Ted!), so I think I’ve got that one nailed pretty close.

That leaves the parts to be laminated to “Bristol” or double that (marked + and ++). I will probably just use the Bristol I’m making the
skin parts from for these, but some experimentation may be in order to see for sure.
I’ve got the feeling that this one is going to take a while! And I might need to buy a bigger cutting mat
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Old 07-20-2007, 02:38 PM
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After much heavy knife work, the main framework around the cockpit. In one aspect, this plane is a good choice to
upsize since it DOES have a lot of framework (amazingly, probably 90% coverage!) and will thus have the needed strength. However it's a
chore to cut all these formers in 1.6mm stock!
I think I see another advantage to large scale. Can't get too close with the camera on those overall structure shots - thus not as much
fault-finding!



Onward to cockpit detail...

Here are the rudder pedals mounted to the shelf that will also hold the instrument panel.
When I first saw these parts, I thought - "wonder why they have church doors in this kit?"
As you can see from the cube, the pedals at this scale are ~1 cm wide. I've already decided I REALLY like the detail stuff at this
scale. This was not nearly as tedious and frustrating as it would have been at 1:33.



Shelf with pedals mounted:



Here is the front of the instrument panel. Like I mentioned before, I tried the tiny wire rings around the gauge enhancement and was not
really happy with it and the tedium of doing it. So I've stolen Ted's method of printing 2 copies of the panel, using the screw punch on
one of them and trapping some thin plastic in between to simulate glass (which due to light positions, you can't see here). I think this
method looks nice and is WAY easier to boot. I have a added a couple of switches and a knob and made the indicator lights more 3D.
That's about all the extra detail I care to add to this.
There are a ton of little "cans" to put on the back of the panel to represent the backide of the gauges. a pic of those later...



Continuing on in the cockpit, here is a view of the "cans" at the back of the panel, and an attempt at simulating wires. I don't have a
pic of this section of a real cockpit to show the route of the wires, so I'm just more or less following Pawell's lead on this. I'm not
too hung up on being exactly right here.



And here we have the completed control stick and on the right you can see the seat support structure.

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Old 07-20-2007, 02:39 PM
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Haven't had much time at the mat this week. I did get the throne done, finally!



Have finished up the central cockpit detail, with a few floor doodads (floordads?) The rounded knobs over on those levers I made by
building up globs of glue/paint mixture.



Next up is the right cockpit side wall. Unlike most Halinski kits, this one is flat, and has framework that is built up to the outside,
as seen here. The whole thing slides in between the bulkheads when done.
I was a bit alarmed in that I had to trim a good bit off the length of this part to fit between the bulkheads. I test fit the inner skin
part to my framework to check to make sure I did not have the bulkheads way off, and it seems spot-on perfect, so this piece must have
just been designed a little too big. At 1:33 it would have been a little less alarming!



Next bit of cockpit detail - the right wall and it's "hangers on".
There are a few bits of extra detail here. Most obvious is the oxygen hose and the fitting at the free end. It's made from very thick
floral wire, wrapped with thin floral wire ("paddle wire", actually, 26ga) and painted.
The red radio buttons are also wire, cut a good bit longer than needed, and pushed down through holes made in the box with a pin before
cutting it out. Then flow some CA on from the back to hold them in place.
I'm printing 2 of each part sheet, a thick one that's more or less the proper upscaled thickness and one from normal 65lb stock. I'm
using the thin version for most of the folded and rolled bits. That leaves another copy of each part, and where there is detail printed
such as knobs, I'm using my punch to cut just that little bit out and paste to the larger part, to get a bit more 3D effect.



Left side of cockpit done. A few extra knobs and such added.



Finished cockpit, left side:



And right side again. The inner skins also carry some fairly involved sills and frames that meet with those white spots here on the tops
of the cockpit walls.


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Old 07-20-2007, 02:40 PM
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Hard to see in this pic, but this is a little detail that lives under the upper rail inside of the inner cockpit area skins:




And jumping ahead, 6 skin parts complete the fuselage center section. I was hoping for that magic Halinski fit here, but it was not to
be. I must have left the formers a little too big. I tend to cut on or outside the lines and I hardly ever sand them by default.
Magnified by scale, I was left with skins not nearly meeting up. Luckily I did a bunch of dry fitting on the outer skins! So I pulled
the inner skins back off, dremel sanded the frames a bit, replaced the inner skins with regular card stock instead of the thicker
bristol, and fought it every step of the way. It came out OK, but it was not pleasent! there's a bit of a registration mismatch visible
hear near the back, but it will (I think) be covered with wing fairing.

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Old 07-20-2007, 02:40 PM
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Today we have the forward fuselage sections, including some built up structures I'm calling "vent boxes" for want of a better term.
This is the forward 2 sections assembled, then a WPS section is cut out. The assembled basic box and pipe are at the bottom.



Next is the box installed into the fuse sections. The pipe is an exhaust waste gate. As you'll see in later pics, there is a vane that
can be closed at the end of the pipe. When open, exhaust is emitted here at the front. when closed, the exhaust is forced to the BACK of
the plane where the turbochager lives, and is vented there after compressing intake air. I think this is one of the reasons the Jug's
fuse is so deep, since it has to duct exhaust and intake air from front to back and compressed air from back to the front. That's a
bunch of pipes! I wonder why this was put in the back? Seems like an overly complex arrangment. Perhaps for balance?
The little semi-circle seen here is added structure that will be cut off once the sections are mated.



Next image is the 2 front sections and boxes mated with the section previously attached to the main fuse sections.



Finally, the completed sections with waste gate vane and vent parts. The forward part of the box seems to hold some sort of radiators.

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Old 07-20-2007, 02:42 PM
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Tail

Here's the aft skeleton assembled and attached to the main structure. When I say this fuselage is solid, I'm not kidding. Talk about
over-engineered! It's solid interlockng frames from the forward spar slot back to the tail. And is it ever HEAVY! This is a good overall
shot illustrating how big she's getting, shown on an 18" mat.



Here we have an intercooler duct box:



And the duct box installed in the fuselage. That sloped piece inside comes up and joins the fuse skin, so that's why it's painted with
the patterns.



Next couple of skin parts installed, and the turbocharger just barely visible at the top (The round thing). I alluded to this earlier,
but will mention some details about this plane's turbo system again here. As you can see the turbo is in the BACK of the plane. It was
placed here to aid in weight distribution. But it makes for some long piping runs. The intake air comes in the bottom of the cowl and is
ducted to the back. Some of it is diverted into the intercoolers to cool the compressed air, and vented out the sides here. The rest
goes into turbocharger, compressed, through the intercoolers, and back to the front of the plane. The exhaust comes back here to drive
the turbo and is exhausted at the top of this turbocharger (well, bottom, when the plane is right side up) and out the duct you'll see
in the last photo.



Completed rear of the fuselage (well, except for a couple more scoopy doodads added later).
I encountered a couple of head scratchers back here. First, that skin that surrounds the turbo exhaust duct. You can see how it is
curved up on the sides. The way this part is designed, it is one piece and the part at the front of the duct was supposed to be curved
up like the sides. I don't know about you other hombres, but I just don't have the mojo to be able to make such a complicated bend and
make it look like something. So I cheated and trimmed the part back around that duct so I did not have to curve it, plus cut it into 2
parts to make the whole thing easier.

The other thing is that all the parts on this model are printed assuming you might leave the wheels up, so you have to cut out the tail
wheel opening. No biggie, but the wheel well inner liner was also solid, so I had to glue it on first to get it stable, cut the opening
from the skins and put them on, and finally use the skin openings as a guide to cut out the liner opening. Maybe this is standard, but
it's my first such encounter.

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Old 07-20-2007, 02:43 PM
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Here are the fixed tail bits in place. This model is NOT designed for moveable control surfaces. I've been looking at it trying to
figure a way to do it anyway, but so far I'm stumped as the design does not make this easy without major mods. Frankly, I don't think
it's terribly important on a static display model, but I'll continue to noodle it a bit.



Here are the tail control surfaces attached. I did not hinge them. Not smart enough to figure out how without some significant
redesign....

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Old 07-20-2007, 02:44 PM
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Been working on the motor, time consuming even with a lot of modelling time, which I've not had! Plus I went slow, trying to make it
look better than the last ones I've done, and I am pleased with the result. Here she is, all 350+ parts!

As you can see, I added a few extras. Laser cut nuts from Draf Model really add a nice "dimension". The ignition harness is some large
floral wire wrapped around the top of an Aleen's glue bottle to get the circle shape, then CA'd the "wires" onto that. The material I
used for the wires is really great stuff - it's 1mm "Stretch Magic" bead and jewelry cord. This stuff actually feels like rubber coated
wire. It's a bit shinier than I'd like, but we'll pretend this is a brand new engine right off the assembly line!

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Old 07-20-2007, 02:45 PM
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So, since this is an upscale, there surely is not a commercially made canopy available! I've been wanting to join the ranks of Ted, Carl, Shrike, and others, so now was the time to set up my own vacuforming rig!

I got an unfinished jewelry box from Michaels and did the holes on the bottom, sealed shut the top (which is now the bottom). Mine's a
bit larger probably than others since this project called for a large canopy. I hope it won't prove to be too large later on for smaller
stuff!

Shown here is the box and the finished canopy mold made from the sculpy clay, baked, and sanded. Like Ted, I stole some of the kid's
legos for a temporary stand.



I'm using the standard (by now) clipboard plastic holder, and added some good strong clamps to the sides.

For now I've decided to go "old school" and used the stovetop / 2x4 stand method to melt the plastic and found it worked well.

It might be a function of the thicker (0.020") plastic I'm using, but I found the melt quite slow and controlled. I thought I was going to be
really rushed lest I melt the plastic to the stovetop if I didn't move quick enough!

One thing I noticed - as soon as you peel the protective film from the plastic it has a lot of static attraction for every mote of dust
in the room! I spent a lot of time getting it all off!



And here is my finished first attempt. It came out OK, but I'll probably do some more to try to get it better. Among other things, I
think I made the shoulders of the mold too pronounced where the canopy edges are to be and this made the bottom edge areas flare out too
much.

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Old 07-20-2007, 02:46 PM
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Got the canopy and gunsight done. Here is the sight and a view inside the front of the canopy.

If you notice the canopy pastic looks quite opaque. This is partly a trick of the light I'm using to work under & take the pics. It
looks much clearer in person. But it's also partly really not as clear as I'd like. I think it's because I probably went TOO thick on
the plastic and it might not have stretched as smooth on vacuuming as a thinner plastic might.
Next time I'll go thinner. What do you other vacu-formers use? 0.010? 0.015?




An overall view of the complete canopy. I doused the overhead swing arm lamp for this one and the plastic looks a bit clearer, closer to
how it looks in person.

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