HubertB

To make a long story short : the wing in the kit has almost the right thickness (should be 22% of the chord - the chord is the « depth » of the wing from front to rear - i.e., at the root - where the wing meets the fuselage - so that is 22% of 133.35 mm = 29.4 mm ) but the kit’s wing profile is too symmetrical between the top and the bottom wing. The original Davis airfoil was more rounded on the top wing and flatter on the bottom wing. Plus, a key feature of a wing on any aircraft is the incidence. The incidence is the angle between the aircraft’s datum line (the « mid » line of the fuselage when the aircraft is flying horizontally, and the line that goes from the middle of the leading edge curve to the trailing edge. On the picture I inserted, this line is shown clearly. Any wing is set at a certain incidence, which contributes to the lift - and drag - generated by the wing. On the B-24, this incidence angle is 3.26°, which makes the trailing edge be positioned lower than the middle point of the leading edge. The impact is that the bottom wing seems to be almost flat, when the top of the wing seems to slope sharply from the point of maximum thickness to the trailing edge. On the kit, the wing seems set at less than 1° incidence, which makes it appear too « flat ». Thus the trailing edge is too high relative to the top of the fuselage. With the wrong profile, this contributes to spoil to appearance of the wing. Check Iain’s pics on LSP. They show the overlay between the kit’s wing and the correct Davis airfoil, positioned at the correct incidence, and the corrections Iain is attempting to modify both the profile and the incidence. HTH Hubert

See my previous post about the correct wing profile, in this thread. The wrong profile issue of the kit is compounded by the too small incidence (the drawing in my previous post has the right incidence, i.e. 3.26°), which is apparently slightly less than 1° on the kit. Iain on LSP is using the same data and internet site as I showed in my posts to determine the right profile. He seems to be getting there changing the wing to a more correct profile and incidence. Most likely, as I mentioned, he will have to correct the angle of the nacelles to bring them back in the slipstream, and may ending having an issue with the MLG legs angle as well. Nothing that can't be corrected when you have had the guts to correct the wing to start with ... Hubert

... And, talking about power, the consumption budget of a (smallish) nuclear power plant Hubert

Hi guys, I have an urge to start the venerable Matchbox Lysander, with some advanced detailing, and finish it in the famous target towing « bumble bee » scheme. Those who have, or have seen, the kit, will remember its somewhat « agricultural » level of detailing. The frame in particular looks way overscale, besides being wrong in some areas, like the wing structure girder. Here is where I am looking for help. The fuselage tubular structure was square tubes for the front, and round tubes for the rear. But the question is : what were the dimensions of the section of these tubes ? I cannot find any reference with these indications, which must however exist somewhere. If any of our Canadian friends have access to the CWH Lizzie, or other survivors, or any of our UK friends to the Shuttleworth or Hendon museum survivors, or to documents with these data, any help would be greatly appreciated. Hubert

Exactly, Martinn. I much prefer Miss Mc Gillis to Tom Cruise Hubert

... And this is the very reason why I bought my Sea Fury without the folding wings (that and the fact that an aircraft is always more beautiful with its wings spread, IMHO) Hubert

Ditto ! Hubert

I have run out of superlatives so long ago with your builds, that I try to leave time between my comments (not « likes », mind you ) , but it goes without saying that I LOVE each and any of your updates, Peter ! Hubert

Apparently, HPH seem to have decided to go IM with this one, Peter (most likely short run à la Special Hobby, at least that is my speculation based on the « czech connection » pf HPH) Hubert

Welcome on LSM ! Gotta say that keeping unfinished kits for 30+ years is what you British must call « fortitude » Hubert

MEK will work fine on ABS (as on PMMA, aka Perspex) Hubert

Just a (friendly) basic physics reminder that the brunt of the weight will be taken and withstood by the main landing gear ... The nose gear will only take a small portion of the total weight, just the extra required to tip the balance the kit « nose heavy » ... Hubert

Ok. Sorry for the thread hijack. It’s certainly not up to me to tell you what to do with your kit. My inputs were certainly more for a general discussion point of view than specific to your build thread. Hubert

Wow ! Fantastic ! You have done outstandingly in rendering a beautiful kit of a beautiful aircraft. Hubert

Looking at the kit pics in this thread again, it seems an even bigger issue than the airfoil profile itself is the wrong incidence (which was 3.26 ° on the B-24). This could be corrected by altering the shape of the fuselage slot in which the wing box slides in. It remains to be decided, however, where to position the axis for this slot rotation. It seems to me that the trailing edge is too high compared to where it should be, but it is also very possible that the leading edge is too low as well. Rotating the slot cut with an axis at about 30% chord could do the trick IMHO, but this is just « Hubert’s eyeball Mk 1 guesstimate » without even having the kit in hand. If you modify this angle, do keep in mind that this will likely alter the angle of the MLG in relation to the wing, and, more importantly, a cut would be required to bring the engine nacelles back in line with the airflow, and not pointing upwards. But this would correct a key issue of the kit without major surgery on the wing itself (which would however still miss its characteristic « bump » at 30 % of the chord). Hubert

Tell me, do you really like German stuff ? Or is it a fortuitous coïncidence ? Nice output, btw Hubert

Congrats to all the winners ! (Looks like I am the only one who did not get anything, btw . But it’s ok, It’s not like my stash needs to grow any further ) Hubert

Well, I was misled by too cursory reasearch, and consequently misled you. Please accept my apologies. I felt the profile above did not look like the wing of a B-24 at the root. This is indeed a « standard » airfoil. But the airfoil section was evolving, from 22 % thickness/chord ratio at the root to 9% at the tip. 15.9 % is just the normal airfoil as Davis designed it. This means the root thickness in 1/32 should be 2.93 cms. The get the right profile, the image above should be replotted using the 22 % T/C at 29.6 % of the chord. Hubert PS: below is the plotted Davis airfoil for 22% T/C ratio and 3.26 % incidence. Sorry for the visual clutter. I did a screen capture on my ipad. Looks definitely more like the B-24 wing at the root, IMHO, and certainly not like what Hobby Boss have designed. It seems the site I could access to in 5 minutes, and enter plotting data in less than that, is not available from mainland China ...

Forgot to add the Davis airfoil profile picture. Here it is. Chord at root in 1/32 should be 13,34 cms and max depth 2,1 cms. Hubert

Back to modelling basics, which means going to research and data. The Davis wing in this scale should be 2.1 cms thick at the root, the max thickness being at roughly 30 % of the chord. And the wing should be set at 3.26° incidence. The pics published of the kit wing show a symetrical profile, and possibly a too flat incidence, which compounds the perception of something wrong. And, it would really be stretching to imagine another manufacturer release another 1/32 Lib (there was no other one than the Monogram kit in 1/48 after all, remember ?). So the options are three : don’t buy the kit, buy the kit and live with the problems, or buy the kit and correct the issues, yourself, or via an AM fix. Hubert

I’ll add my own wishes, in my mother tongue « Joyeux Noël ! » and my new country of residence’s « Feliz Natal ! ». And, Ivan, I wish you all the best in your new home country, and a smooth settlement. Hubert

Hey, as Jeff reminded, after all, it’s a Kitty Hawk kit ... so cats should like them ... H7bert

Good to hear a bout the save, Ernie. Now for those of us who have sometimes experienced spilling one of those glue bottles, a large wooden block can with a middle cavity in which you insert the bottle can save you. Alternatively, you can epoxy-glue the bottle in the middle of a metal tin lid (like a tea box lid for instance). Gives a wider base that makes spilling virtually impossible, and a container to receive the spill if it occurs. Alternatively, you can, like me, claim that you never, nor will ever, spill one of these ... Hang on, to achieve that, the best way is to not model at all Hubert

Would love to, especially if I can choose the proving ground (like the streets of Paris, where I have a few scores to settle with guys who believe the « Code de la Route » does not apply to anyone driving a vehicle with less than 4 wheels or more ... Mind you, two tracks is technically not four-wheels, is it ? ) Hbert

With the discussion going on in another thread, how many liters of displacement, and how many mpg (or liters/100 kms) ? And do they have a metallic silver option ? Hubert