JayW

Those rockets!! Very impressive. And so small. John - where do you get your Future? I still have some, but it's a little tired. I cannot find any more.

I just shake my head in amazement. You sir have a way of making your stuff look like a shrink ray was applied to a real aircraft. Bravo.

OMG!!!!! The master of paint.

Wow Paulo! There is a whole world of 3D print products out there, isn't there? I may contact this fellow but it looks like he is very busy. And he has incorporated a metal pin into his Macchi gear. I didn't see the stress testing. I'd love to know what material he is using, he may not want to divulge that! Thanks Tony - this option was bandied about when I was designing the F4U gear some years ago. After my stress test, I abandoned it thinking I had the issue resolved. That Corsair is one heavy model, alot to ask of those LG. I was not enamored with this idea then or now for a number of reasons - one, the metal rod must be near-on perfect shape or else during assembly it will bend (or fracture) the resin "case" instead of the resin bending the rod. Making the rod thinner than the cavity it would reside in would help... Two - I would have to deal with a seam, where right now with the one-piece it is just .....beautiful. One of the best 3D print parts I have ever produced. I show it again: No seam. A weak excuse I guess. Three - alot of work! But you know, there is nothing stopping me from giving it a try. I might surprise myself. Thanks for the suggestion. Exactly Guy. I have the file still (an STL). I could obtain another resin, maybe what Peter is using for the Sea Fury, and use the file as is, or I could send it to Shapeways as is, if they convince me they have the right stuff. Frankly this issue has messed up my feng shui. But discussing these options have done much to settle me down. As OBG said - "Squirrel!". So gotta get on with it. Update very soon.

OMG - lay that thing down!!! It's literally priceless. I know about big models, but this thing is huge. When I did my 1/18 P-38, I could not do anything to it late in the build without it bumping into something. It's a miracle I finished it without breaking off more than I did. Man that thing looks like it's flirting with the sound barrier (in the vertical) just sitting there.

Thanks Tim! However, to break apart the F4U main gear would be near impossible. I will do what I can to gradually push it back into shape, and then unload them in some fashion. Meanwhile - this Sea Fury of Peter's is going to be heavy. Let's see where it goes.

Oh I am wringing my hands now! I have been following Airscale's progress on his 1/18 Hawker Sea Fury - another fully 3D printed effort. A magnificent one too. Well, he did up a beautiful mostly 3D printed landing gear, placed it under normal model dead weight load, and found over some time (only a week or two) that it sagged permanently. This set my hair on fire, because of this: My own lower gear strut made from the same resin Peter was originally using. So, I took a closer look at my 1/18 F4U, whose LG were 3D printed although with a different (but similar I think) resin, and has been completed for nearly a year now. I got this: Last year, at the completion of this model, this was not the case. The tire was square with the ground plane, like it should be. So the resin has sagged some. What to do. A long time ago I used a pot metal aftermarket landing gear on a 1/32 Thundrbolt, and over time the gear sagged very noticeably. I ended up bending them back to shape, and putting a strut under the fuselage between the ground and the fuselage lower surface to unload the gear. Unfortunate, rinky-dink, and ugly. I fear I will have to do the same thing to the Corsair.....but I don't know if I will be successful "bending" the resin back to shape. The question though is what to do about this problem with the P-51B. I love my landing gear so far. The struts came out awesome. But I highly suspect they will not hold up over time. Peter has switched to another resin for the Sea Fury, and I will be following with much concern to see if it is better. If so I will follow suite. Maybe Shapeways can come to the rescue and print me up some struts with some guaranteed stronger stuff - I'll pay, not an issue. Not resolved, but I will work on it in parallel with my current efforts on the forward fuselage.

MOF I was so surprised that I went to the Corsair to see how it's doing. Hadn't paid much attention to it lately: !!!! For those following who don't know what this is, over the last 5+ years I built a 1/18 scale F4U from a Blue Box toy kit, and the landing gear was replaced by a more accurate 3D printed set. Prior to going with this, I actually subjected the gear strut to a load test to see if it was robust enough to carry the weight of the model plus any reasonable shock loads like a bump. It did fine, it never fractured, and even though there was substantial deflection under high load, the gear strut returned to its nominal shape immediately when unloaded. But the test could not predict any kind of gradual deformation over time. Now look at the picture. It has been the better part of a year now since the model was completed, and the gear have indeed sagged. Originally the tire was right at square with the ground; not now. VERY distressing; it snuck up on me. And this sort of backs up Peter's findings on the Sea Fury. Let us hope the ABS-like stuff doesn't do the same thing.

I know it is impossible to do the entire airplane - but man, it gets alot of us thinking. Magical!

Technical discussions are welcome on this thread. But yes the original subject was the Malcolm Hood and visibility. I have been hard at work in Rhino land. Here is a preview of coming attractions: Next post is LH and RH fuselage join with the radio floor and fuselage tank (and the pesky hand pump). The upper radio rack, radio equip and battery come soon after that. Coming soon.

Bali - niiiice! And my gosh you are flying through this build! You'll be done before I start on my wings! Was so surprised to hear about warped Elegoo 8K gray. You will recall I stress tested the Corsair lower struts almost to failure, and they hae held up well. But I don't know what resin they were made of (Tim provided them). I am now worried about my P-51 lower struts, made of the same elegoo 8K. I have had them for months, but no appreciable load has been put on them. I'd better check that.

Pat - so many questions. How did you come up with the perforations on the radio face? Also, how did you make those realistic looking padded tube clamps?

Ah yes the warning label: As we continue to speculate, it makes perfect sense to me for that warning, if as the canopy is de-coupled from the crank handle and subjected to a several hundred miles per hour wind, that the canopy would indeed blow back - fast and forceful. OBG - I have heard from so many sources including testimoney from the actual pilots that seeing was everything. The pilot who spots the other guy first almost invariably had the advantage. Looking for our fighter pilots who are following this build to comment..... As I continue to incorporate this mod to my P-51, it is more clear that it was very involved. The British modified nearly if not entirely all their fleet of Mustang III's (the B/C models). So it must have been worth it, and then some. Either that or the vis from the greenhouse canopy was so poor they felt something ought to be done. Oodles of cash was spent by governments and manufacturers modifying practically all fighter types as the war progressed to a bubble or Malcolm arrangement. All for seeing.

Oh this is really special! Loving it.

OBG asks good questions. At the risk of boring some of my followers on this project, I will pontificate a bit further on this (to me) most interesting major B/C model modification - the Malcolm Hood. This is all just purely analysis of pictures I have. First - "how does the chain connect to and drive the canopy?" The canopy has a bracket on either side at its forward edge, whos function is to attach the canopy to the chain (brackets circled in red): Note the studs protruding downward from the brackets. Those studs engage a special link in each chain - circled in red: "What stops the canopy from going all the way aft and falling off the guides if you keep cranking? Is there a stop?" There are two stops, one on either side, which make contact with those brackets described above: This next picture shows the canopy cranked back fully open - I circled in red the chain-attach brackets and stops: You can see pretty clearly the brackets are either engaging the stops, or there is a small gap between the two. All this picture evidence suggests to me that for emergency egress, the canopy simply slides aft into the stops, and does not jettison itself from the airplane. The red handle somehow (I don't know how exactly) disconnects the hand crank from the chain allowing a rapid aft movement of the canopy. That is all it can do, apparently. Stand by - soon I will post progress on the fuselage tank and radio rack, and preparations for joining the LH and RH forward fuselage panels, always a milestone for any airplane build.

While toiling away with the Malcolm Hood operating mechanism (so glad I am basically done with it), I tried and failed to figure out how the emergency egress system works. I just know one exists - it consists of a red pull handle on the RH side under the windshield, about the same place as the production version of same for either the greenhouse canopy (B/C) or the bubble top (D/K), connecting to a tube that runs along the inside of the RH upper longeron parallel with the chain. From there the tube attaches to a weird crooked bar which is part of the aft sprocket bracket. From there is a cross tube that connects it to the LH side of the airplane. Pictures: The last picture, showing the aft bracket with the crooked bar and the cross tube - the hole for the cross tube is slotted aft and down but you can't see it from that view. That suggests the tube can be pushed aft and down to free itself from the bracket. Also, when the red handle is pulled, it acts to push the long tube aft which will push the cross tube, or something attached to it, aft. So if that is so, what goes with the cross tube? The aft sprocket and aft portion of the chain? ??? One thing is for sure - the hood itself is not going to jettison itself from the airplane, as is the case with many other airplanes. Not with those permanent roller bars on either side of the fuselage, and permanently attached roller guides on the hood. The greenhouse canopy on the B/C, however, looks jettisonable to me. Pretty sure all the Malcolm hood can do, however, is slide aft for emergency egress. The hand crank is going to take several rotations to get it open; could it be that when the red handle is pulled, the chain somehow disengages itself from the hood, or at least the crank handle, allowing it to blow back or be pushed back very quickly? Inquiring minds want to know.

Oops - I fell behind following this amazing build. Don't feel bad about lack of engine detail!! Yours will not have open cowl panels, and with that spinner cone, you can hardly see the cylinders anyway!! Compare to the Corsair with no spinner cone at all and openable panels. Apples and Oranges. When I am detailing an item, and realize that it will not be seen, my enthusiasm suddenly drops off. I have come to be somewhat familiar with how you do the major parts of these big models (fuselage, wings). The only thing I see having changed is a bit more use of 3D print parts here and there to better assure the scratch-built sections are accurate. Now I feel bad trying to 100% 3D print my Cripes A Mighty. I am getting lazy - less and less am I trying to figure out how to fabricate a tough detail. And more and more how to 3D print it. Two different things, one requiring not as much ingenuity and skill. At any rate, I now wonder if I might want to do something like what you do with the wings. We are after all limited by how large our machines are. So far you are capturing the raw power look of this particular species. Nice going!

John- true masters can create clean detail in small scales. Perhaps a reason I like big scales, because I just can't do that. You are putting on a clinic.

Cannot wrap my head around the small scale, I have been in 1/18 world for so long. It is a different world. Go John.

It was quite a ride, but I have a Malcolm Hood mechanism to show you. This is what I am trying to represent: The chains, the emergency release pushrods, the sprocket support fittings, the crank handle, the emergency release handle, and the black cover plates. Not the cross-tube. That comes later. First, just as what happened so many times back in the 1940's when -B's and -C's were getting their hoods, I had to relocate the recognition light switch box on the windshield frame. From here: To here: Had to be done to clear the new crank handle. All the parts printed up pretty well. There is alot of small detail, especially the chain itself, so I went with the 30 micron thickness setting on the printer (I normally use 50 micron). After careful removal of supports, and carefully painting, I got this collection of details: And I had to be exceedingly careful at all stages of preparation - the long thin parts are so very fragile. The black plates are not 3D printed - just old fashion scratch build with styrene sheet and Meng nuts. Ok that was the easy part. Installing these details into the airplane was the hard part - a most stressful and "stimulating" experience, trying to pry into a small space all these parts without breaking anything. I broke one of the chains, but had a spare and used it. Everything else worked out OK, sort of. Pictures: The 3D printed chains are a success, I am happy to announce. Let's see the finished mechanism in the fuselage jig: I need to do a better job painting up the rollers - I know. But that comes later. Glad to put this sub-project in the rear view mirror! Next I believe is a bit of miscellaneous clean-up chores, and then the lower radio floor and the fuselage tank. I've been waiting forever to get started on that. Hope you like the chain drive! Later.

YAY!! Looking forward to re-following. Looking very cool so far.

Getting back onto the subject at hand - the Malcolm Hood drive and emergency release mechanisms, I have finally got Rhino 3D representations of the parts (13 in all) that I will 3D print. It was a bit of an integration nightmare, as alot of stuff gets crammed in between the flanges of the upper longerons. And my longeron flanges are thicker than the real thing by a good bit (scaled of course). Also my longerons are not quite as wide as the real thing, to account for my skin gages, which are also thicker than the real thing (scaled). This all works against me shrinking the space to work with. Neverthless here are some hard won details that I hope will look representative once painted and assembled (assuming they print up OK): Yup - you are looking at a 3D printed chain (with sprockets). I measure, from the pictures I have, a 1/2 inch pitch and about 1/2 inch wide. Scale to 1/18, and the links are much smaller than I could scratch build (something I managed to do on the Corsair tail wheel door mechanism a while back - but the chain was a bit larger). It is alot to ask of my printer - we shall see. You also see other details that have had a whole lot of artistic license applied to them. Shortly I hope to show you the actual parts installed into the fuselage side panels. Stay tuned!

Oh cool pic indeed! Thank you Antonio. Some things to notice: 1. Relocated recognition light electrical box (a few inches forward) seen through the side window windshield glass (with what appears to be a natural metal finish bracket) 2. Some dark colored strip of putty or something along the periphery of the aft enclosure cutout - clearly meant to seal the gap between the hood and the fuselage crown when hood is closed. First I have seen that - I wonder if that was common... 3. There are five sets of rollers exposed with the hood open. All other pictures I have seen either period or modern have six sets. Mine too. Hmmm... Is the hood in this pic not fully open? Or, were more rollers added at some point to address a service issue..... 4. You can see a portion of the round outboard end of the crank handle / forward sprocket support bracket peaking out from behind the roller rail just aft of the windshield. You'll see that on mine too pretty soon. 4. The girl is very hot. I hear you on modern restos. However I am very confident that the cranking system is accurately represented. All are consistent, and anything that can be gleaned from period photos seem to be in acordance. As for escape - the Malcolm has an emergency jettison mechanism, including a red pull handle not unlike what we see on all production Mustangs whether greenhouse or bubble top canopy. You will see that on mine soon. Upon your suggestion, I sent in a querie to the Imperial War Museum in GB, since the British back in the day modified practically every one of their many P-51B's (or Mustang Mk 3's as they called them), to have the Malcolm hood. We'll see if they respond or have anything. Hope they hurry - I am not waiting.

Awesome LG! I must say - one of my most frustrating problems with 3D printing parts that fit together with one another is trying to account for the shrinkage/expansion thing. It is small but it is there, at least with the resin I use. A pin or shaft that fits inside a bore on a fitting, like you have there in several places, needs to be about right on. Not sloppy, and not too tight. I guess Timmy has that down.

The heater outlets are defined on drawings - they are part of the production airplane. The Malcolm hood mod however is just that - a mod. And no drawings are available. But wait! I think I have it solved, and the solution was in my pictures all along: LH side, the flex tube is attached to a convenient fuselage frame further forward. RH side, the flex tube is routed under the map case forward to an empty spot on a radio mounting bracket. I can do that! This is from a modern resto, so I am going to have to hope it fairly well represents what was actually done back when. I am going to declare the mystery solved though.