forum.ww1aircraftmodels.com
WW1 Aircraft Modeling => WW1 Aircraft Information/Questions => Topic started by: Kampf doppeldecker on May 28, 2014, 08:23:20 PM
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Hi All
Some of you may have seen my post over on the 'great war in the air forum' entitled 'Pfalz DIII upper wingtip geometry'.
This explained the unfortunate error in the shape of the upper wingtips of WNW's model, also lower wingtips, although I didn't go into the latter in any great detail. As it turned out, this information was apparently perhaps not fully understood as the post generated virtually no response.
As I am considering purchasing the WNW kit, I wonder if any Pfalz afficionado out there has done an in depth check of the basic accuracy of the kit using available info, all usual stuff, checking aerofoil sections using Baubeschreibung co-ordinates, stagger, wingspan, gap etc. I don't want to fork out £50 plus only to be faced with endless accuracy issues. Any help would be appreciated. If something as obvious as the upper wingtip shape was missed then perhaps there are shortcomings elsewhere.
Cheers Al.
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Baubeschreibung co-ordinates? What the heck is that? Never heard of it. Google has failed me.
Also, would it be too churlish to point out WNW's model depicts a D.IIIa? ;)
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Not a Pfalz expert by any means so I can't help much. As there are no surviving originals one can only base opinions from drawings and photos(As far as I know). It might be helpful if you posted your findings on the wing tip geometry here. IIRC your contention is regarding the taper towards the tips?
RAGIII
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Hi Bo,
Used 'DIII' generically. The 'Baubeschreibung' was a basic aircraft spec. issued by Idflieg. Examples are dotted around the Datafile series, there's one in the latest DIII one published a few years back. Satisfyingly, the aerofoil co-ordinates contained in the report on Hecht's DIII agree very closely with the ones in the Baubeschreibung.
It would seem an obvious thing that a kit manufacturer would try for an accurate aerofoil section but the upper wingtip (and lower) issues in the WNW - and all other DIII/a kits, does raise doubts. The WNW kit could be the basis for an accurate replica, it's certainly the 'best of the bunch'.
However, the wingtip thing, as mentioned, does give cause for concern, if this can be missed what else is wrong?. As I say, £50 is no mean sum. Looking at the kit on the net there are several areas for concern, amongst other things the front U/C strut seems to be raked too far forward, too 'straight' under nose profile, should have a very slight curve, although not as much as in the Datafile drawings. Also, the tailplane was fabric covered on the DIIIa, not ply as in most kit reps (all)
Outline accuracy is 'the' aircraft, many years ago this seemed to be important, I recall 'Scale Models' magazine getting 'hot and bothered' over the odd millimetre!. Sadly, it seems concern for basic accuracy has taken a back seat to 'after market' goodies and decals etc.
This is why I ask if anyone has had an in depth look at the WNW kit, again, any help would be appreciated,
Cheers Al.
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Hi Rag,
The issue is in the tip geometry, I went into the topic in detail 'over there' but it would seem they're temporarily offline.
When they're back on I'll transfer the thing verbatim over here. Meanwhile, to summarise, the taper as represented in the WNW kit, and every other kit, is incorrect, 'starting' too far out towards the tip - we're talking upper surface taper at the moment. 'Droop' towards the tip commenced from the second rib out from the aileron root, this in a 'straight line' to the tip (at aileron L/E-aileron false spar area) , creating a drooped tip effect when viewed from the rear, very noticeable. There was also an 'upsweep' to the tip commencing from the same point on the undersurface, this created Washout on the wingtip. This upsweep on lower surface is again, visible in front views as a change in 'straightness' at aileron L/E- aileron false spar line when viewed from front. Aileron trailing edge wasn't straight, but, for want of a better word 'interacted' with the tip geometry in Washing out towards the tip. As I say the whole thing is clearer on the other forum, when they come back on line I'll transfer it.
Cheers, Al.
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Hi Al,
A picture paints a thousand words - do you have any photos or drawings to illustrate your points?
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Hi Ian,
A picture does paint a thousand words. At work at moment. When i get chance I'll post the pics I posted 'over there' of my 1/72 Roden DIII which incorporated the mods mentioned. If you have access to the DIII/a Datafiiles there are a few photos which illustrate the point.
Cheers, Al.
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It sounds like you ought to scratchbuild the wing to get anywhere near the level of accuracy you want.
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I guess the general rule here is How Bad do you want to build a 1/32nd Pfalz? It seems to me that correcting any probable MINOR issues would be far easier than Scratchbuilding a complete Pfalz DIIIa. JMHO. One thing I remember is that there is a bit of frame missing in the interior from the instrument panel down. I also seem to remember that the Cockpit floor should be curved vs. straight. In the end I don't think you will get any "Fatal" flaw thread going here so the choice will be yours to buy or not. I do think you should post your pictures relative to the wing tip geometry as I did find that very interesting in your original thread!
RAGIII
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Hi Rag,
As I said, the WNW kit seems to be 'the best of the bunch' and obviously can provide the basis for a sound replica, nothing needed as drastic as a complete scratchbuild. Re 'Red Baron's' comment, I have no desire for complete accuracy, it's unrealistic and therefore, in my opinion unnecessary. We all adopt 'acceptable tolerances' for ourselves, for example, on 1/72nd aerofoil sections I work to, say, a 5 thou tolerance, I'd be prepared to accept the odd 1/4 mm in wingspan or fuselage length.
The incorrect upper (and lower) wingtip taper missed not only by WNW, but all manufacturers, is a major inaccuracy as it is very obvious in any rear or rear 3/4 view, how it's been missed is baffling, it's as easy for a manufacturer to get it right as it is to get it wrong. All I ask for is a decent representation of the original, what would Rudolf Geringer think!, poor old lad.
As Ian says, a picture paints a thousand words, I tried to post the pics that appeared in my post 'over there' but for some reason it wouldn't take them, file too large perhaps?. As you say Rag a 'Fatal' thread would be a non starter, so there seems little point in duplicating my original post from the other forum, I'll stick with the pics and leave it up to the individual as to whether to incorporate or not.
I'd like to see the Tamiya treatment given to the Pfalz DIII, a '1/72nd Zero job', I have a sneaking feeling they just might get the wingtips right, without much effort.
Cheers, Al.
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I see what you are talking about now Al. It really is a rather glaring error. Once you see it it's hard to "unsee it" :(
Well it gives us something to do, eh?
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Not me, mate! It stays as it is! ;D
VB
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Hi Al,
A picture paints a thousand words - do you have any photos or drawings to illustrate your points?
this is what he's talking about... even more obvious from a straight rear aspect, WNW doesn't have such a photo on their site, but look in the Herris book for several examples:
(http://www.wingnutwings.com/ww/vFADF2312/www/products/model_kitsets/32006/archive_photos/Pfalz%20D.IIIa%208033~17.%20Captured%2027%20March%201918%20(AL0459-040).jpg)
(http://i1255.photobucket.com/albums/hh640/UncleTony1917/ex_zps7c19626e.jpg)
compare to this lovely build (hope vB doesn't mind):
(http://bobsbuckles.co.uk/Pfalzmfj/8.jpg)
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Well now I've seen it I'll bin mine and I encourage Bob to destroy his too.
It was bad enough having that half mm gap on the Junkers aileron. My enjoyment of the hobby is now like ashes in my mouth.
There's too many stitches per rib tape too....
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Well now I've seen it I'll bin mine and I encourage Bob to destroy his too.
It was bad enough having that half mm gap on the Junkers aileron. My enjoyment of the hobby is now like ashes in my mouth.
There's too many stitches per rib tape too....
;D ;D ;D
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Well now I've seen it I'll bin mine and I encourage Bob to destroy his too.
It was bad enough having that half mm gap on the Junkers aileron. My enjoyment of the hobby is now like ashes in my mouth.
There's too many stitches per rib tape too....
/quote]
Shoot! I have 3 kits plus all those extra decal sheets - I'm gonna go bury them in my backyard tonite so no one will see me with them. :-[
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It is a difficult to see but when you do hard to miss thing.
Every kit has flaws, some oversights, some due to constraints, nothings perfect. I for one expect them to. If someone expects a perfect kit then I suggest they give up the hobby. I'm not having a dig at anyone (well maybe one well known doomsayer on Aeroscale who thankfully steers clear of WW1)
I imagine if this had come to light to WNW before the kits release it would have been addressed. It still builds into a beautiful model and would give the likes of our illustrious Bo weeks of fun correcting it. (joke Bo :D)
£50.00 compared to £100 plus for a Tamiya Spitfire that doesn't even have armament in its gun bays... Flaws or not its a No brainer to me anyway.
Keith (plodding through his new CII.. Flaws and all)
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Well now I've seen it I'll bin mine and I encourage Bob to destroy his too.
It was bad enough having that half mm gap on the Junkers aileron. My enjoyment of the hobby is now like ashes in my mouth.
There's too many stitches per rib tape too....
NEVER!!!!!!!
lol
Bob Von StickingwithmyPfalz
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Hi All,
Nicely seen and illustrated Bo, as you say, once seen hard to 'unsee'.
Of course, every kit has it's flaws, no-one, including myself expects perfection. But what is expected is a decent representation of the aircrafts salient points. The wingtip 'thing' is very noticeable once seen, all it requires really is a little time looking at photos and taking in detail. As said, the taper started from two ribs out from the aileron root on upper and lower surfaces, less on the lower surface, all this of course creating tip Washout.
The aerofoil section obviously changed with all this and it is possible to construct approximate co-ordinates using various methods, the section from centreline to a point two ribs out from aileron root was, of course constant.
Copied my notes (photographed them) this morning with the intention of posting same, but still struggling with file size, have to get somebody to show me how to shrink the files. These notes are from back when the original DIII Datafile was published - was it 1988?.
It's all a question of what the individual wants in the final model, if you're happy then that's fine. I say again, the WNW kit is probably the 'best of the bunch', but the wingtips, and this is applicable to all manufacturers, should have been more closely looked at.
Keep on looking Bo, the more you look the more understandable it all becomes.
If Rudi Geringer looked at kit wingtips I think he'd be a bit concerned about possible loss of control approaching stall ! !.
Seriously though, it is a glaring omission and should have been seen, no drawings show it either, apart that is from the l' Aerophile side and front elevation.
I'll try to post the stuff I mentioned, phew!, going for a Cornish Pasty now, nice ones at shop round corner!.
Cheers all, Al.
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Al is right, it comes down to what the modeller is happy with. I am one of those that are quite pleased with my WnW Pfalz, warts and all. As I age I find myself practicing the "ignorance is bliss" system of modelling ;)
I am somewhat concerned about the stability troubles, so as a precaution, I have grounded my Pfalz indefinitely. ;) ;D
Cheers,
Ernie :)
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CORNISH PASTIES Now you're talking :P :P :P
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Wow, it's great that this topic is recent, since I'm currently designing the master for a 1/48 Pfalz D.IIIa kit for Glencoe Models. The base kit is the old Aurora kit of the D.III (from the '60s, I'm suppose), and the new parts will be the lower wing, horizontal stabilizer, and a mounting part for the Spandaus, comprising the feed/ejection chutes and gun mounts. I'm surprised the kit is as accurate as it is. One of the notable inaccuracies is the number of ribs in the lower wing. At least that won't be a problem for the new boxing. Another problem is the sharp angle where the trailing edge of the wingbox meets the fuselage, but that can be fixed by the modeler, as can be the lack of underwing detail, but I digress. Any help in making the parts I'm designing more accurate will be much much appreciated.
I notice the washout is mentioned on this drawing in the Datafile book, with arrows evidently indicating the point on the span where the washout starts, although I had not noticed the arrow pointing at the upper wing:
(https://farm4.staticflickr.com/3882/14394025164_672667a761_h.jpg)
The WNW kit has a couple issues with the lower wing. First, while it has an access panel for the aileron control cables on the upper side of each lower wingroot, the footboard forward of it on the left side is missing. I've never seen a photo where the footboard is clearly missing, and of course it is necessary (like the boards in my attic--lath and plaster is not enough to support a fellow who weighs 18 stone). The lower wing has the tip washout, but it's also got the outermost full-chord rib spaced about 10% farther out than the usual spacing, which I think is about 348mm. I see no evidence for this in any photos or drawings. Even this contemporary one:
(https://farm4.staticflickr.com/3852/14206435159_189888ecb8_o.jpg)
The top wing washout is hard to see in most photos, being above the photographer's height. But you can see it in several of the WNW archive photos. Thankfully it's one of the easier things to correct on a model. The washout is formed differently in the two wings: the upper leading edge droops near the tip because the wing is twisted farther back (probably at 1/4 chord), but the lower has a straight leading edge due to its axis of twist being right at the leading edge. Incidentally, both the Aurora D.III and my D.IIIa have the lower wing tip washout, and formed correctly, but this kit's upper wing has no washout.
Anyway, it's not always easy to spot all these things on your own, which is a major reason for inaccuracies in models. Any help with getting the lower wing right will be greatly appreciated.
Cheers,
Ed
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Well Im gutted, all the money I have spent and now its wrong. :'(
Care ;D no I don't, the kit looks sunning and the builds on here (and other forums) just blow me away.
Cant wait to start it
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I am pretty sure that 99.9% of modelers adopt the attitude of - who cares - Accuracy of a model has been a contentious issue ever since models have been produced and will always be a focal point to certain "rivet counter" modelers. To the naked eye from a respectable viewing distance nearly all models look to be a very good representation of the real thing, or damn close to it, but how many of us walk up to a model with micrometer in hand and a high powered magnifer just to make sure that the model is exactly a scale replica of the real aeroplane. No matter how hard a manufacturer tries to get his model kit accurate there will always be those who will criticise his efforts and well within their rights to do so, but as I said, the majority of modelers are extremely happy with the kits and will keep buying and building them, I know I will, none of my aircraft will ever be grounded because the stitch count is wrong :)
Des.
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Well said Des.
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Des, very well put and I am certainly one who will most likely HAPPILY build my Roden DIII without changing the Geometry! That being said for those in the get it correct school I will also appreciate seeing their resolution to the "Issues"
RAGIII
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I too have little sympathy for the modeler who raises accuracy issues merely to complain, expecting to shake the box and out comes a perfect replica. It's very useful though when modelers raise accuracy issues to help other modelers fix them, to make aftermarket parts to correct deficiencies, or as input for those who are designing masters for kits.
I think I've figured out how a Pfalz D.IIIa late lower wing should look, and where the inaccuracies are in both the Datafile book's drawings and the WNW model. The former shows the aileron control cable access panel and foot strip being too narrow--they should extend to the wing box. The latter lacks the foot strip on the left wing (hard to see on any photos, but I'm sure it's there) and it has the outermost wing rib unequally spaced, which does not appear to be the case in their own reference photos, though it's almost impossible to tell. These problems and the lack of washout on the upper wing are all pretty easily fixed, so I think the WNW kit is well worth the money.
The Glencoe kit will also be worth it at ten bucks, but I'm still making my list of modifications to make it accurate. At least the lower wing will be accurate as it can be while fitting the lower fuselage.
I don't mind at all having to do a little plastic surgery.
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I too have little sympathy for the modeler who raises accuracy issues merely to complain, expecting to shake the box and out comes a perfect replica. It's very useful though when modelers raise accuracy issues to help other modelers fix them, to make aftermarket parts to correct deficiencies, or as input for those who are designing masters for kits.
I totally agree. Any criticism of the WNW kit has to come with an acknowledgement of how amazingly good the rest of it is. Still, it is an error that does not require a magnifying glass to see once you are clued in. I bet dollars to doughnuts that if the kit is ever re-issued they fix this.
It is not going to be an easy fix for most modelers and I'm sure of the few that are aware of it most will live with it quite happily -- and that is fine! Others will see it as a challenge to set their model apart from the crowd -- that's fine too! It also provides an opportunity for the aftermarket guys -- also a good thing, in my opinion.
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i wonder if a fix could be as simple as application of heat whether hot water or hot air and twisting the wing into shape? ive dont this before to add washout and/or dihedral . is it not possible in this case?
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i wonder if a fix could be as simple as application of heat whether hot water or hot air and twisting the wing into shape? ive dont this before to add washout and/or dihedral . is it not possible in this case?
I don't think that would address the tapering airfoil section. :-\ To me that's what pops out when you look at the archive photos compared to the kit. But maybe the washout exaggerates the apparent taper when viewed from the rear aspect and so maybe that might do it??? Dunno.
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hmmmm
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Reprofiling the upper wing surface from the correct rib would be the answer, simple in itself but redoing the ribtapes and stitching to match WNW's after would be the hard part. I'm hazarding a guess the spar must taper down from said rib steadily from what images I can see. A lot of careful heart in mouth sanding. ???
As said by many, they can live with it, I'd be tempted to try on another build, I'd love to build another Pfalz DIIIa but Just as I consider it WNW sneak another Albie out imminently and the gameplan changes dramatically.
Keith
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Sanding away at the surface is the obvious answer, and maybe the only way in the end, but I am wondering if there isn't another approach. What if you made very thin castings of the upper and lower surfaces -- sufficient to preserve the detail, which are then applied to a new, correctly profiled core?
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Sanding away at the surface is the obvious answer, and maybe the only way in the end, but I am wondering if there isn't another approach. What if you made very thin castings of the upper and lower surfaces -- sufficient to preserve the detail, which are then applied to a new, correctly profiled core?
Bo,
This may be bordering on the obvious but are you talking about cutting off the tips from the proper rib and then making a cast/core for just the areas needing correction? Or conversely the whole wing?
RAGIII
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Bo,
This may be bordering on the obvious but are you talking about cutting off the tips from the proper rib and then making a cast/core for just the areas needing correction? Or conversely the whole wing?
RAGIII
I mean the former, just making casts of the tips (top & bottom) and forming them into a sandwich that is then appended onto the original plastic. Somehow. Probably a crazy idea though.
Maybe a better idea would be to make casts of just the rib tape detail that could be inserted into trenches on the re-profiled wing...
none of this would be easy...
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I am posting a scan of the upper wing of the Roden Pfalz DIII. (Please forgive the crudeness of my abilities to convey my thoughts in photos). If I am seeing things correctly one needs to re taper the wing from either the red or yellow lines towards the tip on both upper and under surfaces? If so I would think you would have to stop prior to the actual edge as this would sand to a paper thin edge? Again I apologize for the poor workmanship on the scan. it also seems that this operation would be somewhat simplified on the roden 1/32nd kit as one could just sand all of the ribs and use archers rib tapes as needed to replace all on the wing 8)
RAGIII
OOps, forgot the pic at first ::)
(http://i1185.photobucket.com/albums/z349/rickgeisler/Pfalz%20wing%20taper/scan0065_crop_zps0fce98d3.jpg) (http://s1185.photobucket.com/user/rickgeisler/media/Pfalz%20wing%20taper/scan0065_crop_zps0fce98d3.jpg.html)
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Hi all,
Glad there's been an eventual acknowledgement / realisation of the taper issue. As myself, and, more recently Bo have said, once seen impossible not to see. My original post on the other forum explained the whole thing completely, but as mentioned, generated little response. Still waiting for my 'Whiz Kid' with these modern electronic boxes to show me how to resize flies to 'postable' size.
When she gets round to it I'll post the photos of my 1/72nd Roden DIII which incorporated the mods, also photos of notes I made back in 1988 which explain the whole thing in complete detail. These are 'gathering dust' stapled to the back cover of the original Datafile, hey, was it really twenty six years ago I made those notes?, By Gum, I was but a slip of a boy!.
The notes will explain everything raised and make clear what needs to be done to the tips (or not done - if anyone wants to build from the box that's fine, depends what the individual wants)
Rag, briefly, the taper, or 'droop', starts from the second rib out from the aileron root, the red line in your photo, there is also, as previously mentioned 'upsweep' on the lower surface commencing from same point.
Best thing for me to do here is to post stuff mentioned above which explain it all a lot better than I have time to do now, stand by on that. Interestingly it is possible to come up with 'guesstimated' aerofoil co-ordinates for the tips using various datums, we of course know the co-ordinates for the constant areas of upper and lower wings. On the notes I hope to post mention is made also of aileron geometry and how this tied in. If anyone has either the original DIII Datafile or the later Issue take a look at the pic of 4184/17 on page 21 in the original issue or page 24 in the later issue. Hold page obliquely and sight along top surfaces of upper surfaces of front and rear spars (upper surface of front spar only visible in later issue) this illustrates commencement points, this is only 'straight' on the spar surface itself and on the aileron false spar and aileron leading edge. The 'staightness' was eased very slightly on the rib profile, a very slight curve to the tip, 'almost straight'. Also look on same photos for corresponding 'upsweep' on lower surface. Phew. Stand by for posts and keep taking tablets all,
Cheers, Al.
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Hi all,
Was going to bed but I'll just stick this one in. To achieve 'taper' on my 1/72nd Roden DIII I used needle files, then progressively finer grades of 'Squadron sticks', finishing up with polishing grade. Aerofoil section was worked to, or rather in the tip area, 'guesstimated section' as no co-ordinates are available for this area. 'Sag' between ribs was then worked in with small curved Swann Morton blade (forgot blade number) easing sag in areas of lesser curvature and where aileron false spar was approached. If I was working on the WNW kit I would get rid of, or reduce the existing rib tape detail as this is overscale anyway, stitching under same could then be perhaps represented by very fine HSP suitably 'tweaked'. This would have been a damn site easier in1/32nd,
Cheers, Al.
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Al the best way to post large images is to use a third party image hosting service such as Flickr, Picasa, Photobucket, etc. all have free plans. There are detailed instructions I think in the hints & tips section.
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Thanks RB for writing this up (again). I tried to find one of the many previous topics on this to link here but failed. Perhaps this should be a FAQ -- or maybe added to the site's Help topic?
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and it sounds so complicated reading the instructions but it is truly a few clicks away.
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Thanks you fellas,
Popping over to Flickr et al, see if I can suss it out.
Cheers Al.
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I got fed up with Photobucket meddling and everything changing & becoming less simple to use and have started using imgur.com. I haven't had anything of note to post since so hope its better than the FU Photoshop seems to have become in it's desire to chase technology ::) Happily plodding along modelling but not snapping what I've done... bad me. :-[
Keith
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Hi all,
Eventually used a rather cunning thing called 'Pic Monkey' where one can fiddle with pics no end then wang them back on one's electronic box, modern technology, absolutely marvellous !.
As I mentioned previously these notes were made back in 1988'ish shortly after the DIII Datafile appeared and have been stapled in back of same since then. First pic :-
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2nd:-
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3rd:-
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4th:-
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Note last two lines of page three:- 'a change of contour to match the aileron washout......., correction here, it is of course washout, I worded this wrongly. The notes emphasise more strongly than I have previously tried to describe how aileron geometry tied in with tip geometry.
Cheers for now, AL.
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I see what you are talking about now Al. It really is a rather glaring error. Once you see it it's hard to "unsee it" :(
Well it gives us something to do, eh?
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Glad it has been seen, it was driving me crackers!,
Here's a view of the upper wing which was originally posted on the 'other' site. Note how the lighting on the left wing tip shows the taper from two ribs out from the aileron root. It's also possible to see the aileron T/E 'change' towards the tip. The kit is the 1/72 Roden DIII. Also incorporated were correction to aerofoil section using Idflieg 'Baubeschreibung' and capture report co-ordinates and slight rib position correction, all this as previously described. Another pic to follow,
Cheers, AL.
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Other pic,
Notice again lighting showing effect,
Cheers, AL.