Flying Tigers P-40B Warhawk

[palindrome]

Thanks Don. I've already found my first problem on the next step. Having learned, the hard way, the lesson of "measure twice, cut once," I've discovered that the slots into which the wing spar fits are not the same length. One is about 1mm longer than the other. Gah. I will figure out some form of internal bracing, cut to the length of the shorter one, and then adjust when it's time to insert the spar, making sure I get the dihedral symmetric.

[palindrome]

Well, I'm going to put this down for a few days.

After a day of working with pieces printed on normal paper to try to figure out how the cockpit and control panel are supposed to fit into the fuselage section, I have reached the conclusion that they simply do not fit, and cannot be made to fit. In the meantime I've done enough damage to the control panel and cockpit that I may need to redo them completely.

The fuselage section is simply incorrectly designed. In the actual airplane, it is supposed to go up and over the top of the control panel, but this model cannot be built that way, period. Looking at other build pictures (e.g., on various versions of the model on ecardmodels), it's clear that the control panel has to fit into the cockpit opening and extend above the fuselage. But doing so requires that the control panel be attached so that the edges of the control panel are blocked by the stuff on the sides of the cockpit - entire gauges are blocked. And the rudder pedals are getting squashed into the bottom of the cockpit.

Even then, I cannot get the edges of the cockpit opening in the fuselage section to actually line up with the top of the cockpit. And if they don't, the rear bulkhead and the seat won't fit either.

So it's time to put this down before I smash it in frustration.

The answer MAY be to redesign the rudder pedals so that they don't attach to the back of the control panel. Then I may be able to lower the control panel so it fits into the fuselage section properly. We shall see.

[MacSongLi]

I feel really bad for you palindrome. You have done a great job to this point, but I understand your frustration. Hopefully time will be your friend.

I too have purchased the kit, but haven't even printed it yet.

Good Luck!
Gary

[elliott]

Smart man. You're wise to walk away for a while. I'd hate to see this wind up in the trash can, you've done so well with it up to this point. Hope the time away helps, just please don't leave us dangling..

[palindrome]

Well, having made the decision that I'm going to need to rebuild the cockpit, I did the work (mangling) to figure out how to fix the problem. The marks for where the control panel is to be mounted are about 3mm too high (that's a lot at this scale) and about 0.5mm too far back. And the rudder pedals were correspondingly about 3mm too tall. I've printed off a new page with 2 copies of every cockpit piece, plus 2 modified rudder pedals and cockpit shells.

Still planning to take a day off. Then I'm going to start by gluing up just a modified cockpit shell, a control panel, and the modified rudder pedals and make sure that fits properly into the fuselage segment. Once I'm sure that's right, I'll rebuilt the whole thing. Probably just a couple days work to get back to where I was, since I've already done it once.

[milenio3]

The truth of the matter is that I finished my P-40 because of plan PRIDE. I didn't want to say that I tossed a model away. And it is not a good finished model.

But you are right, this model is not well designed, it lacks of clear instructions and other things.

I also bought the model of George Welch's P-40, but of course I won't even print it.

I know that with time, passion, patience and more, the model can be built. I guess Chris Gutzmer was one of the first to built it. But there are other P-40 models around that can be a good alternative (Dr. Zarkov's come to mind, with a neat P-40 shark mouth).

PS My photos from Facebook were somehow removed. I need to upload all photos again.

[palindrome]

Thanks. I will finish it. I have the cockpit rebuilt and it fits properly in the plain-paper fuselage section. I'm in the process of putting the actual fuselage section together now. I'll post an update in a day or two when I finish this section. I've already found a few other issues in upcoming steps, but I think this is the last of the really hard parts.

[Don Boose]

I hope you manage to bring this project to completion, palindrome.

I am very sorry to hear about the problems with this kit, since I very much wanted to build the two Pearl Harbor P-40s, but I do not have the skill to compensate for these problems.

Don

[palindrome]

I will definitely finish it, Don, and I'll keep noting what I've needed to change/fix to get it done. Hopefully that will help make this more straightforward for the next builder. A lot of this may still be attributable to my inexperience, as this is only my 3rd airplane build.

[palindrome]

OK, here we go. Back on track.

First, after mangling the crap out of them trying to figure out how they all fit together, I rebuilt the cockpit shell and control panel. IMHO they're better this time:



I did one silly thing with the control panel - the layer with the glue tabs is the bottom layer. I really should have made it the top layer, because that would have made it a bit easier to line up the control panel on the cockpit shell walls. That was dumb, but it worked out OK (I wasn't going to rebuild it again just for that).

Now let's talk about what I had to fix to get things to all go together. First I had to shorten the rudder pedals (compare 25 and 25rev in this picture):



I'm pretty sure you could use the stock rudder pedals - just glue them up higher on the back of the control panel. I redesigned them to make the pedal itself a little shorter so the proportions stayed about the same. Since I was making up a new PDF file to print off multiple copies of all the parts, it was easy to add this.

Second, look at the location of the left-most control on the lower part of the control panel. Compare it to the original version shown on the first page of this thread. This part (5c) will hit the box (1) on the left wall of the cockpit if you put it too far to the left (I think I overcompensated, but c'est la vie).

Those two things are what caused all my problems the first time. Keeping the rudder pedals off the floor of the cockpit and keeping 5c from running into 1 caused me to have the control panel WAY too high. For things to come out right, the control panel has align exactly with the rear-most and top-most edges of the glue boxes on the cockpit walls (the tabs are much higher and deeper than their glue spots - the tabs extend below and to the front of the markings on the cockpit walls.

Next adjustment I had to make was to part 17 - the mounting brace for the machine gun breeches that are visible in the cockpit. This MUST be a right triangle to fit on the back of the control panel. But the hypotenuse of the right triangle is ~2mm too long. You need to score it inside the marked glue tab to get it to fold into a right triangle:



I discovered this too late in my first messed-up cockpit. This time, I scored just the two inner fold lines, then measured exactly where I needed to score it to get it into a proper right triangle.

Here is the fully assembled cockpit:



Next was to prepare the fuselage section. This model is really odd. The fuselage section closes over at the base of the wing spar. Then the wing is attached, and then finally a separate curved piece is shaped to properly round the bottom of the fuselage. I'm not sure I could ever have imagined designing a model this way.

Anyhow, the spar slot cuts all the way through the bottom of the fuselage section - the spar fits so the very bottom of the spar is flush with the join of the fuselage tube. I reinforced the top of each end of this slot with a small piece of cardstock.

Also, this design leaves the spar attached to nothing but the cardstock. I wanted a more rigid gluing surface. I made a copy of bulkhead C (which is at the front of this section, and measured up 7mm from the bottom. I cut this shape from 1mm cardboard, and glued it to the front of the spar slot (I put a scrap into the slot and held the mount in place against it. I only glued it at the bottom, not all the way up the curve. I didn't want to risk distorting the shape of the tube, since the rear bulkhead flares out some. This provides a good gluing surface when it comes time to install the spar.

I also made the cockpit rails per the instructions, and colored the inside of the cockpit a medium gray, because bits of it are visible above the cockpit shell, around the control panel:



Now the moment of truth - gluing the cockpit into the fuselage section. The instruction have you attach the fuselage section to the previously-completed nose section BEFORE inserting the cockpit. IMHO, that's absolutely foolish. There's no way to support the front of the cockpit to glue it in place properly if you do that. I glued bulkhead C inside the glue tabs at the back of the nose section, then test-fit the fuselage sections until I was comfortable I could slide the cockpit section on after installing the cockpit.

I also built a jig to support the cockpit in place in the fuselage section while it's glued. It's just a stack of 1mm cardboard scraps that butts up against the wing spar brace, with a couple of longer pieces that go over the top of that brace. Then I glued the cockpit in place in 4 steps - right rear corner, left rear corner, right front corner, left front corner. That would have been impossible if I had already joined the fuselage sections.



Now, note that I still have a problem. The cockpit sticks out of the back of this fuselage section. I think this is because the top edge is not 100% flush with the edge of the cutout. But it can't be unless I lower the control panel even more (which would require shortening the rudder pedals even more...):



For the moment, I'm leaving it. We'll see how the rear fuselage & bulkhead fit. But I expect I'll have to trim this, which will be a pain.

(continued in next post; I'm out of room for attachments in this one )