Dornier Do 18-D *Finished*

[blg63]

Hi,

I have just read these 27 pages and have no  word to qualify your work. In french, époustouflant.

I found your post because I was searching "D0 18 cockpit" on Google as I have a Do 18 D project with the matchbox kit.

From the informations you get from  the handbücher, you gave a seat to the pilot ans a sliding jumping seat to the observer-commander on board. Do you have informatiosn about the organization of the seats depending of the types  D2-3 and G ?

Here is a picture found on Alamy of the Do 18 D 2 ou 3 (?) 60+E52 where the observer is obviously on a seat and the gunner seems to be seated between him and the pilot.

Best regards

Bernard

 

Edited November 21, 2017 by blg63

[pheonix]

This is really coming together well now - good to see the componebts being fixed into place and an aeroplane emerging from the many parts. I really admire your skill and patience with all those brass fittings for the ailerons and flaps - a lot of fiddly work but well worth it. The new flaps will be fine without surface detail - as you write panel lines and other such irregularities on the actual machines were so small as to be invisible at this scale. Looking forward to seeing the wing mounted soon.

 

P

[bbudde]

1 hour ago, blg63 said:

where the observer is obviously on a seat and the gunner seems to be seated between him and the pilot.

Hello, it's just a guess, but I have never heard of a three seated cockpit in the Do 18 (or any other german type). It could be that he kneels between them like you would do from middle of a backseat in a car looking foreward.

[jrlx]

Good progress, the fuselage is taking shape and the canopy is really transparent!

 

Cheers

 

Jaime

 

 

[CedB]

Nice work Tony - that canopy looks impressively clear, good job

[TheBaron]

20 hours ago, hendie said:

I would hazard a guess that you's be fairly safe to have your swans looking where they were going.

That has a visual logic to it persuasive enough that I shall go with that option hendie. 

20 hours ago, hendie said:

 

...and the support framing for the engine access door on the Alexanders ALX300 SLF

Maybe we should do a member's sweepstake in order purchase this mind-bogglingly-priced tome? 

https://www.amazon.com/Structural-Adhesive-Joints-Engineering-Adams/dp/0412709201.

19 hours ago, blg63 said:

I have just read these 27 pages and have no  word to qualify your work. In french, époustouflant.

I found your post because I was searching "D0 18 cockpit" on Google as I have a Do 18 D project with the matchbox kit.

From the informations you get from  the handbücher, you gave a seat to the pilot ans a sliding jumping seat to the observer-commander on board. Do you have informatiosn about the organization of the seats depending of the types  D2-3 and G ?

Here is a picture found on Alamy of the Do 18 D 2 ou 3 (?) 60+E52 where the observer is obviously on a seat and the gunner seems to be seated between him and the pilot.

Bernard - merci beaucoup for such kind remarks!

 

You hit upon a vexed question regarding the seating arrangements - one that has caused me considerable thought to work out due to a certain level of ambiguity between various sources. I have no detailed plans for the 'G' seating I'm afraid so any remarks below only apply to those 'D' variations that I have various handucher for....

 

In these handbooks none of the views of the cockpit (either photographed or plan views) show permanently-installed side-by-side seating for both pilot and observer-commander. Air International (April 1980, Vol.18 No 4) had an article entitled: 'The Do 18 ... Dornier's Whale Calf"'. which states that there was a collapsible seat for an observer/commander which was used for instruction. You can see that listed as part 38 here from the graphic that accompanied the article:

(It reminds me I've yet to add that detail myself...along with seatbelts)

 

The author of the Air International article makes no mention of the source for that statement however and I'm dubious about it in operational terms.

 

The same article makes no mention at all of the sliding seat fixed to the rear bulkhead of the cockpit, but which is well-illustrated and clearly identified in the manual as being for the flight-engineer (partly I imagine as there are a plethora of fuel tank levers situated directly above his head when seated in that position...) for take-off and landing The only other confirmed seats are back in the radio/navigation room - one of either side respectively as you see them placed on my kit interior.

 

In one of the plan views I have of the 'D' rear section there is additionally what appears to be a seat right up by the rear gunner's position - this looks so odd to me that i'm going to remove it from where I'd stuck it on to my interior. It feels wrong, I can't explain it any other way.

 

The Air International article doesn't therefore quite add up with the handbucher, whilst the maintenance handbucher (as is sometimes the case) may have to be regarded as only part of the story to understanding installation and use of specific structural features on operations. The seating conclusions I've reached trying to reconcile maintenance drawings, the article, and photographic sources (including your lovely image!) are as follows.

 

Cockpit

Permanent Pilot's seat (port) - confirmed from multiple sources. (as shown in model interior)

Collapsible Commander/Observer seat (starboard) - confirmed from multiple sources. (To be added to model interior)

Sliding/Collapsible seat for Flight Engineer - confirmed from multiple entries in various handbucher. (as shown in model interior)

Radio Room

Wireless Operator/Navigator Seats - confirmed from multiple sources. (as shown in model interior)

 

No evidence bar one drawing for a seat up by the rear gunner's position - this will be removed from the current interior configuration.

 

In summary then Bernard your photo is very plausible as reflecting the three-seat layout, with the Flight Eng. seated behind and between the pilot and commander, and leaning forwards during the shot.

 

As my model will be in a posture undergoing maintenance, I'll be leaving the commander's seat in a collapsed orientation in order to allow access to the forward cockpit bulkhead separating cockpit from the forward gun position.

 

I hope this helps?

19 hours ago, pheonix said:

The new flaps will be fine without surface detail - as you write panel lines and other such irregularities on the actual machines were so small as to be invisible at this scale.

I had thought so too Phoenix, but it's nice to have some backup!

18 hours ago, bbudde said:

but I have never heard of a three seated cockpit in the Do 18 (or any other german type).

I have to reluctantly disagree with you Benedikt, but only on the grounds of such seating being permanent - in the case of the commander and flight engineer these seats were collapsible items i.e., used for take-off and landing and then folded away during flight whilst the crew manned operational positions.

15 hours ago, jrlx said:

Good progress, the fuselage is taking shape and the canopy is really transparent!

 

4 hours ago, CedB said:

Nice work Tony - that canopy looks impressively clear

 Jaime, Ced: Muchas gracias you two! To think it used to be the packaging the file set came in....

 

[blg63]

Thanks a lot Tony for this long and  precise answer . As I'm building a D, I'ill copy your work with 3 seats. From the picture I found and others, even if the seat of the commander was collapsible, it had a seat back (normal, it was commander seat). I have the Air International and it asked me more questions than it gave me answersr with  only the support  represented.

Best regards

Bernard

[corsaircorp]

Hello Dear Baron,

What a wonderfull job, and you will finish her in due time....

Congratulations !!

May be start looking for a Do 24 Fonderie at 1/48 

I've started the Steam Pigeon... Very nice kit indeed !

Still can't believe that it is a Matchbox kit !!

Sincerely.

CC

[bbudde]

12 hours ago, TheBaron said:

reluctantly disagree with you Benedikt, but only on the grounds of such seating being permanent - in the case of the commander and flight engineer these seats were collapsible items

Ok,  Klappstühle between the pilots and the co-pilots seats make sense for a take off or landing. Although Germans could do that of course

[TheBaron]

21 hours ago, blg63 said:

Thanks a lot Tony for this long and  precise answer

My pleasure Bernard. The detective work on this build has been quite enjoyable but I've learned to take many web pictures and some book illustrations with a pinch of salt regarding exactitude.

21 hours ago, corsaircorp said:

Hello Dear Baron,

What a wonderfull job, and you will finish her in due time....

Congratulations !!

May be start looking for a Do 24 Fonderie at 1/48 

I've started the Steam Pigeon... Very nice kit indeed !

Still can't believe that it is a Matchbox kit !!

Thanks for that you big sweetie Cc!

1/48? Heaven forfend that I should switch to such vast dimensions...

15 hours ago, bbudde said:

Although Germans could do that of course

 

Further 'making-good' is underway at present:

A handheld No.10 blade has turned out to be the most useful implement for scraping back Milliput along a curved seam.

 

After a couple of sessions with scalpel and primer were ready to move on now:

Underneath:

Ready for some scribing and detailing with various access openings:

The main wing has also had some considerable attention, carving back the epoxy on the underside and filling gaps around the hebel and lager parts top and bottom. It's drying out on the stove for a while as it's a damp and freezing day today and everything is drying slowly!

Some kabuki masks arrived today as well:

So, where now?

 

1. As mentioned the sponsons need some detailing and then back to the main wing to finish installing the various actuators and hinges for the flaps/ailerons. I'll leave them off for painting but want to work out a sequence that will let them attach securely at the end. 

2. Prior to closing the fusleage I need to sort out the kommandantensitz, add seat belts, and then begin work on the gun mountings. Regarding the latter structure, there are some excellent plan drawings in the Drehkranz D30 manual that Benedikt unearthed a while back:

 

There's enough in these for me to design some custom parts, so I'm going to have a go at 3D printing the structure that lets the weapon move vertically on the azimuth ring. The plan is to use digital copies of these drawings as background image planes in Maya for sculpting references, then send these as an .obj file into the printer software for conversion to an .stl format for output. At present I'm working out whether the printer resolution will enable that to be printed as a single part, or need to be broken down into sub-assemblies.

 

More on that process as it develops.

 

No progress tomorrow as off to Dublin for the day to see Kathe Kollwitz's drawings up at the National Gallery:

 

More at the weekend bambinos!

Tony

 

 

 

 

 

 

 

[giemme]

8 minutes ago, TheBaron said:

so I'm going to have a go at 3D printing the structure

Really?   That's proper multimedia modelling  Very curious to see that  

 

Ciao

[corsaircorp]

Oh Tony, 

What a pleasure to see again some gaellics !!

Everytime I tried to pronounce it was a great pleasure time for my irish friends 

Have a nice week end, and say Hello to Malachie Mulligan !

Sincerely.

CC

[jrlx]

Good progress. I'm also very interested to see how your 3D-printing plan turns out, as I've been considering 3D printing as a possible future endeavour for adding detail to models.

 

Cheers

 

Jaime

 

 

[CedB]

Very neat work on the sponsons Tony, they're looking very clean.

3D printing eh? Can't wait to see what that produces...

[TheBaron]

On 11/23/2017 at 4:44 PM, giemme said:

Really?   That's proper multimedia modelling  Very curious to see that  

 

18 hours ago, jrlx said:

I'm also very interested to see how your 3D-printing plan turns out, as I've been considering 3D printing as a possible future endeavour for adding detail to models.

 

11 hours ago, CedB said:

3D printing eh? Can't wait to see what that produces...

Well, I've been steeling myself to have a go  - I'm lucky to have an opportunity at work - so I figured by announcing such a thing in the thread I'd burn my boats and have to get off the proverbial rump and do it instead of justmusing about it. I expect a few false turns here and there along the way but I'll do it in full visibility so people can see what's involved.

11 hours ago, CedB said:

Very neat work on the sponsons Tony, they're looking very clean.

And now I've gone and mucked them up again this evening! (but in a good way...)

On 11/23/2017 at 6:20 PM, corsaircorp said:

What a pleasure to see again some gaellics !!

Everytime I tried to pronounce it was a great pleasure time for my irish friends

It sounds like you and me have the same language skills in that dept. Cc!

Mrs B. is a mellifluous -if infrequent- Irish-speaker, whereas I am largely limited to identifying a post-office and pointing to red dogs...

 

Well, back from Dublin in a more refreshed condition than anticipated - one of those icy-cold but sunlit winter days that is so restorative to the spirit. The drive across the Midlands at daybreak was a dramatic tableau of the Turneresque - great fallstreaks of snow, sleet and rain against the rising sun. The exhibition we went to was magnificent - if you're ever in Dublin the National Gallery is an excellent place.

 

A brief snooze upon returning then and itching to do a little more tonight. I'm at that stage where I'm deciding what remaining flaws with the kit need ironing out in terms of shape - I'vehad my eye on both stummel (sponsons) for a while but I've also been in conversation with Bernard (@blg63) who has convinced me that I need to rethink slightly the angle of the return I was putting onto the finished bow. He was kind enough to share s comparison graphic which showed that the D3 variant (this one) is a kind of halfway house between the blunt/rounded earlier D variants, and the more angular and later G variant. Not a massive change, but one that would look wrong if not finessed. That'll happen once the fuselage is closed-up.

 

Right then. Sponsons. There are two shape issues with these both to do with the leading edge. On the actual aircraft it is both thinner along the leading edge, and has a more linear profile. You can see what I'm doing here with the sihrsc, linearizing the curve along the front:

Reducing the the front slope in thickness needed a sanding drum on the Dremel-tentacle (Dremtacle?):

Original cross-section on the left, reduced on the right:

Hopefully that's clear enough to show the distinction between the original beefy-Botham-ness of the kit OOB and the required modification of about 1-1.5mm off, graduating in to the root. 

 

Looking more acceptable one the brutal grinding was smoothed down. Port:

Not port:

I've also been incrementally blobbing Mr Surfacer on the seams and gaps around the actuators and so forth on the trailing edge of the wings. That's coming along and should be ready for smoothing down tomorrow - a fiddly job no doubt.

 

A final thing before I go; something I'd meant to mention a while back. If you're having trouble with shadows photographing your work on the bench with a single light source there's a handy little Android app called Pocket Softbox:

https://play.google.com/store/apps/details?id=com.pimentoso.android.softbox&hl=en

It lets you use your tablet (or phone, but the light will be smaller) as a lighting panel that you can interactively control the colour temperature of in order to match artificial light sources, or even match to daylight from the window.

Image on the left is just lit from one side with an LED, the one on the right with Pocket Softbox running and dialled to the same colour temp as the LED, giving no different colour casts to the image. Both shot with same exposure values:

As you can see it gives a soft and even fill light to mitigate the shadows and give a greater sense of form to objects. (I deliberately stuck both lights in shot for the demonstration - you'd obviously want to avoid doing that yourself). There's also Photo Soft Box Pro that does similar for the iOS users but you fanbois will have to shell out a few $ for the privilege...

 

Ta-ta for now.

Tony

 

 

 

 

 

 

 

 

 

 

[giemme]

Dremel action, one of my favourites in modelling Very neat job, there

 

Ciao

[The Spadgent]

Well Tony, what a lovely couple of days ( yes you read right ) to catch up on this. Simply wonderful work going on. I think you’ll find the 3D print process pretty good as long as you have a clean base model. I found the plastic a pain to sand down however. Remember that bomb. I’m looking forward to actually getting back to the bench but until then I have beautiful builds such as this to scratch my itch. 

 

Johnny boy.

[hendie]

nice drumelling there. 

 

2 hours ago, TheBaron said:

so I figured by announcing such a thing in the thread I'd burn my boats and have to get off the proverbial rump and do it instead of justmusing about it.

 

There's nothing like raising your head above the parapet is there?

 

I've used 3D printing in the past. I had good result with the SACRU and the tail wheel mounting on my first Wessex build.  I had much less success when I tried printing anything with tubular shapes though - especially small diameters

[pheonix]

Not having a Dremmel I sometimes envy those who do as I sit sanding away with coarse and then finer grades of glasspaper! The new shapes look very good - much more like the real thing. I do not envy you having to sand down all those actuator ports on the wing though.....(see you cant use the Dremmel all of the time!)

 

P

[jrlx]

Great job reshaping the sponsons!

 

Cheers

 

Jaime

 

[bbudde]

4 hours ago, TheBaron said:

Looking more acceptable one the brutal grinding was smoothed down. Port:

Looks great of course!

But what would you do with it?? Going swimming?  100% is ok!!!!!! I guess. Oh please stay calm!

Edited November 25, 2017 by bbudde

[perdu]

Dremeltastic mate

 

That's the sponsons surrendered so not much more to worrit about

 

😉

Edited November 25, 2017 by perdu

[TheBaron]

19 hours ago, giemme said:

Dremel action, one of my favourites in modelling

Mine too Giorgio! Though over-enthusiasm with it is a clear and present danger in my case....

16 hours ago, The Spadgent said:

I think you’ll find the 3D print process pretty good as long as you have a clean base model. I found the plastic a pain to sand down however. Remember that bomb

I surely do! I've been examining the 3d clip art that was printed out when all the protoyping gear was delivered to work and I hopeful the Cubepro with the smaller nozzle might help - he said with all the confidence of one who's never done a 3d-print in his life!

16 hours ago, hendie said:

There's nothing like raising your head above the parapet is there?

No there's not! 

I'm a firm believer in making an injudicious utterance about such matters, consequently then being forced to step up to the envelope and push the plate. Or something.

16 hours ago, hendie said:

I've used 3D printing in the past. I had good result with the SACRU and the tail wheel mounting on my first Wessex build.  I had much less success when I tried printing anything with tubular shapes though - especially small diameters

Duly noted hendie. For that very reason was intending to print only the mounting 'shoulders' that fit on the azimuth ring and use metal parts for the arm the gun is mounted on and the framing for the seat/stirrup affair that dangles underneath - which makes the rear gunner look like a testicle in a truss:

I don't think that sling affair is used on the front gun however, due to the limited height oopat'bow. I must check that.

16 hours ago, pheonix said:

Not having a Dremmel I sometimes envy those who do as I sit sanding away with coarse and then finer grades of glasspaper! The new shapes look very good - much more like the real thing.

Thanks Mr. P. For certain jobs it is certainly a godsend, especially with a flexible extension that means the motor unit can hang by your bench whilst grinding away with it dentist-style. Much more controllable.

 

That's not to say though that there are times when it is infinitely preferable to have all the information coming to your fingertips through sandpaper and file when shaping contours for example - as your beautiful work demonstrates.

15 hours ago, jrlx said:

Great job reshaping the sponsons!

My thanks for that Jaime!

14 hours ago, bbudde said:

But what would you do with it?? Going swimming? 

A barmy Baltic summer and those sponsons make the perfect maritime picnic platform don't they Benedikt?

6 hours ago, perdu said:

Dremeltastic mate

 

That's the sponsons surrendered so not much more to worrit about

Ta Bill.  

There's a series of circular 'lids' (don't know what else to call them) running down the top of each one with just enough recessed and raised circular details on them to require careful thought in the representation thereof. (Am I the only one on here that finds the end of my longer sentences turning into something that the great Rumpole might have uttered after a claret lunch...?)

 

Today has involved further tidying of wings and sponsons in and around and mainly attending to this:

The gun-waving bits front and back. Sketched here just to get a sense of structural breakdown there are a couple of points to note:

1. The mountings (or to be more precise, the 'shoulder' bits that sit on top of the azimuth ring and which let the gun elevate/depress ) are not symmetrical the port one is longer  than the starboard one.

2. The framing for the truss that the rear gunner squats into does not go straight across but is a diagonal frame as you see above. I wondered why and presume this a function allowing the gunner to angle his torso sufficiently in order to sight along the barrel of the weapon?

 

Here's an image of one of the actual parts built earlier from a watch cog in the workspace in Maya as a reference image:

In order to get scaling and alignment consistent between both sides of the mounting I elected to create a virtual version of this gear to use as a jig when building virtually - particularly important in ensuring that the ring diameter that we're building to is 12mm precisely:

You can see by now that I'm using the actual engineering drawings from the Drehkranz 30 manual as visual references in the background. These are of great help not inadvertantly introducing any abstractions into the design.

 

The forward part that the tubing mounts into: this simply started life as a 'primitive' square and then sculpted at the level of point and line:

Still a bit fat there but you can see how important good references are at this level. Once they were shaped to my satisfaction I got to work on the lower section (the bit that actually sits on the ring):

Same methodology, with a central disc extruded to produce the bearing that allows the parts above to rotate up and down. Note also here the difference in size I mentioned between port and stbd versions of these parts.

 

Bringing both sets of parts together for initial test fitting and scaling of various dimensions:

You can see how to begin with the inner negative space of the upper part was too big for the central bearing. The outer dimensions were fine so this took some tricky finessing with the inner set of polygons in order to bring them in closer to hug the bearing in a more convincing manner.

 

Being in 1/72 I was conscious that although more detail could be added (such as the various bolts &etc.), such items will look better made by hand and added later, due to the defining limits of printer resolution.

 

Some test renders:

This was important to check for any obvious gaps or irregularities in the mesh before outputting:

Rather usefully (I think something to do with abstruse copyright reasons) I discovered that Maya no longer provided for a direct .stl output:

A tad annoying. Despite having formatting software for both the CubePro and Ultimaker printers, there was no way around this annoyance, which in the end consumed a couple of hours footering about for a result. A straightfoward .obj export into Cubepro was not possible, and in the Ultimaker suite it was coming out with scaling and integrity issues, producing a frustrating interregnum. Eventually I discovered a free utility from Autodesk called Meshmixer that lets you bring in an .obj and tidy it up before exporting to a range of 3d printing formats:

https://www.meshmixer.com/

After much huffing and puffing I finally got the design into the Cubepro interface at the right scale:

You're probably wondering two things at this point:

1.Why'she left the ring on? A: It just seems easier to leave this on as a mounting plate for those parts during printing. The parts can be cut off later as you would with removing parts from a casting block.

2. What are those off bits hanging down underneath the ring  - they weren't there before? A: Meshmixer added these to plug a couple of hidden gaps in the geometry when analyzing shape integrity. Handy enough and they'll be similarly cut off at the end.

 

I won't be convinced that all the above has worked of course until I'm holding the actual printed part in my hand as proof of concept; my hope is to try and get this printed either this week or next, depending on when I can get access. 

 

Where did today go?

(Lost in cybespace! )

 

Have a nice evening y'all.

Tony

 

 

 

 

 

[giemme]

Fascinating stuff, Tony - thank you for taking the time to provide such a thorough explanation

 

What is the resolution of your 3d printer, please?

 

Ciao

[bbudde]

9 hours ago, TheBaron said:

make the perfect maritime picnic platform don't they Benedikt?

Yes of course .And I want that fish:

 

Edited November 26, 2017 by bbudde