MikroMir 1/48 DH.88 Comet

[dnl42]

One of the several kits I've wanted for a while is a 1/48 DH.88 Comet--she's just a gorgeous aircraft. Well, MikroMir has obliged. 

 

Here's the beauty shot 

 

And the bits inside that relatively cavernous box

 

 

 

 

 

Markings are provided for all three, not sure which I'll do yet...

 

[fjaweijfopi4j48]

Oh, one of the most beautiful planes ever!

 

[Bengalensis]

Ahh, great choice! I have the same box on my bench, been meaning to start on it any day. Will be interesting to follow your work.

[rob Lyttle]

I want to see this 👍

[Marklo]

Ohh nice, I want one of those too, but possibly in 1/32 to go with my other racers.

Edited June 3, 2020 by Marklo

[Martian]

Ooh! Interesting! You may proceed at my convenience.

 

Impatient of Mars 👽

[dnl42]

Engines are first, for a change in pace. MM only claims light grey and black. Wikimedia commons has 3 pictures of the Gipsy Six R engine, all different colors, including this one.

The info reads:

Quote

One of the original Gipsy Six R racing engines that was fitted to the winning DH.88 Comet Grosvenor House (background) of the MacRobertson Air Race in 1934, the engines were removed from the aircraft following the race and replace with the more reliable standard Gipsy Six Series II engines with about 25hp less.

This suggests its colors are original. It also is consistent with a contemporaneous photo of the engine on Getty Images. While the Getty photo is of the Burberry version, i.e., it's likely a Gipsy Six Series II engine, one expects the colors were consistent. BTW, this coloring is inconsistent with the operating versions on the Shuttleworth Collection aircraft.

 

With that, I'll go with the above photo.

[dnl42]

Wow, those engines are quite an effort! I've built a couple of models with less parts than in one of them. Here's a parts diagram for the engine sprues.

There are 5 parts for the crankcase with mere suggestions of alignment. Much dry fitting and find shaping is needed. The instructions would have you assemble the sides (60, 61) to the top cover (55) in the first step and then get to the rear (43). After much dry-fitting I decided to first attach the rear (43) to the top cover(55) and square them up. This then better aligned the sides (60,61). When attaching the rear, I made sure to make it flush to the rear of the top cover. Note the cylinders have 2 asymmetric sides (69, 72) and are, in theory, keyed to the crankcase bottom (70) to ensure correct orientation. Sadly, the cylinder locating pins are too large for the openings, so I had to drill them out, losing the keying.

 

Now for the errors. The parts diagram and assembly instructions disagree on parts 69 and 72. This bears on the cylinder orientation--we can fix this. Next are parts 73, the valve covers. There should be one per cylinder; sadly, both the parts diagram and actual sprues only have 5. I've looked all over for those last valve covers but they're not to be found. I'll need to make one for each engine. Also notice the pushrods implied with part Pe26, There's no other mention of them. I'll use some 18 mil brass rod for these. Finally, the cylinder tops are apparently keyed to fit the valve covers-sadly the square keying doesn't fit--they'll need adjustment.

 

After a day's off-and-on effort, I've managed to get the crankcase assembled and am now working on the cylinders. Note the two cylinder sides (3 left v. 3 right). You can see the keys in the bottoms of the left cylinders. Hm, lookng at this photo, it's clear the crankcase bottom needs some more shaping...

I'm still thinking on how to paint these beasts. I'm also wondering if these engines will be an example of "at least I know it's in there".

 

Thanks for watching my oh so slow progress... 

[fjaweijfopi4j48]

I wish their 1/72 kit (which I built) would have had engines, even if simpler!

I am afraid the friction may melt the plastic pistons, though 😄, not to mention the conflagration of the fuel.

More seriously, it's nice that the kit has such detail.

You can easily open a gondola side panel to show them.

[dnl42]

@Moa, thanks. I thought about leaving one of the cowlings off or opening a panel, but I fear that would detract from the beautiful lines.

[Bengalensis]

3 minutes ago, dnl42 said:

@Moa, thanks. I thought about leaving one of the cowlings off or opening a panel, but I fear that would detract from the beautiful lines.

I have exactly the same problem; the lines of this machine are so lovely I don't want to open anything. I could even perhaps think of building it gear up in flight...

 

I think we may have different instructions in our kits. In my set there is a symbol telling the builder to make the pushrods from sprue stretched to 0,5 mm dia... I will use Evergreen rod. Too bad about the sixth valve cover,..

[dnl42]

2 minutes ago, Bengalensis said:

I have exactly the same problem; the lines of this machine are so lovely I don't want to open anything. I could even perhaps think of building it gear up in flight...

 

I think we may have different instructions in our kits. In my set there is a symbol telling the builder to make the pushrods from sprue stretched to 0,5 mm dia... I will use Evergreen rod. Too bad about the sixth valve cover,..

Would you be able to scan and email those instructions? If so, I'll PM my email address.

 

Did you find those 6th valve covers? 

[Bengalensis]

1 hour ago, dnl42 said:

Would you be able to scan and email those instructions? If so, I'll PM my email address.

 

Did you find those 6th valve covers? 

Sure, no problem, I'll scan and e-mail.

 

I looked quickly this morning and sure enough there are only five valve covers at the expected location. But I'll give all the sprues a thorough check tonigt.

[SodaCitron]

I've started this kit few months ago. It is a very difficult one and I hope you will get more patience and dexterity than me, along with a decent stock of files, sanding sticks and putty.

 

I always build my aircraft "in flight" so I saved some sanity not building the engine or the landing gear. The engine nacelles are not fit-friendly.

 

Decals are very thin but very decent. 

By hiding 2 small but strong neodym magnets behind the firewall, between the landing gear strut, and using some kind of metal wires (from staples) it would be possible to magnetize one of them, so allowing the display of the engine a-la-demande...

 

Best of luck

Edited June 5, 2020 by SodaCitron

[corsaircorp]

Agreed with Moa and the Martian !!

I'll buy one as soon as I found one !!

Look like a pretty good kit, Thanks for sharing !!

Sincerely.

CC

[Bengalensis]

11 hours ago, dnl42 said:

Would you be able to scan and email those instructions? If so, I'll PM my email address.

 

Did you find those 6th valve covers? 

You have e-mail.

 

They may have updated the instructions, but not the content of the sprues. Only five valve covers per engine in my kit as well. That's not terribly impressive; two resin ones would have been perfectly OK. Not that it will be a real problem in my case, but annoying.

[dnl42]

@Bengalensis, thanks for the revised instructions!

 

@SodaCitron, I'm definitely working the files and filler! I do have small magnets, so I might well try to leave the cowling removable.

 

@corsaircorp, it's going to be an effort, but it will look amazing on the shelf!

 

 

[dnl42]

One engine is assembled. Dang, that took a while!

 

The pushrods and valve covers took some effort to work out. Instead of the 18 mil brass rod I mentioned earlier, I ended up using 28 gauge brass wire. The lower end of the pushrods go into that Pe26 part shown above. The intention was to bend Pe26 into a Z shape with "fingers" going between the cylinders. After getting that Z bend completed, it was clear those fingers were just too big to fit. I started trimming back the fingers to fit but eventually realized they weren't going to work. Thinking a little more, I cut the fingers off leaving Pe26 as a simple L shape, finally getting the right alignment.

 

Next were the valve covers. I first tried to enlarge the square slot for the keyed cylinder top. After eventually getting one to almost fit, I realized they just wouldn't sit right as molded. I finally realized that instead of trying to use the kit parts, I could get a better valve cover by replacing all of them. I first cut the square key from the top of each cylinder. I then took some 0.1 in square Evergreen rod and rounded off the edges to get a basic shape I could slice. Next, I chamfered the four edges of the rod end and cut a slice for one valve cover. I repeated that five more times to make the six valve covers.

 

The rest of the assembly was a lot of shaping parts to remove mold seams and better define the shapes.

 

Painting this will be interesting! 

 

Thanks for watching! 

 

[fjaweijfopi4j48]

Laborious, to put it kindly.

Full steam ahead, nonetheless!

[Bengalensis]

The engine looks beautiful. Good solution with the valve covers.

[dnl42]

Thanks @Moa and @Bengalensis!

 

With one engine built, I decided to move forward with the MLG. Quite a few bits in these, again with much cleaning up and dry fitting before applying glue to plastic. I made one according to step 2.

 

The problem is that while parts 51, 54, and 45 go together is more or less one configuration, parts 40 and 41 could fit over quite a range of positions. The key to their positions is in step 3. For the 2nd attempt, I put 51, 54, and 45 together, then married that assembly to the firewall (6/7). Once dried, I added part 42, making sure to get 42 more or less parallel to the shorter panel of the firewall (bottom of drawing, top in position).

 

And here are the assemblies. I made sure they matched as closely as I could. Also visible are some bits of Evergreen strip that make part 41 look a little better...

 

That's probably all for this weekend.

 

I'm now off to pull some beef (about 6h in the smoker), finish the caramelized onions (about 20h in the slow cooker), make some jalapeno poppers, cole slaw, and carrot salad.

[rob Lyttle]

My goodness, how elaborate is THAT! 

Congratulations on figuring it all out. 

Unless I missed something, I believe that this is deHavilland's first effort at making a "retractile" undercarriage. And it does have a bit of a prototype look about it 

[dnl42]

@rob Lyttle, thanks! A complicated prototype and vague assembly made it quite a trick to assemble. We'll see how well I did with it once the airframe is assembled.

 

I'm supposed to build the nacelles next, but that will mean more vague alignments. With that, I skipped ahead to the fuselage. Once that's closed up, I'll should be able to build out from there to ensure correct alignment.

 

Based on info from @Dave Swindell and @John Aero as well as a review of an image on Getty Images, I went with a varnished wood finish for the cockpit as well as the inner flap surfaces. I painted a base of Mr Color C45 sail color and then brushed Windsor & Newton burnt umber artist water color. While the water color dries very quickly--compared to a week or more for oil color--the consistency can be fussy to get right.

 

 

 

[dnl42]

I decided the wood was too dark. Yellow ochre and burnt umber in approximately equal amounts looks much better. I also clear-coated the watercolor with Tamiya X-22.

Quite a lot of dry-fitting and filing got the bits above to properly marry. 

 

I also worked on the front IP. I used some Blacken-It on the PE IP panel and a Molotow Chrome pen on the back of the IP film. At the bottom of the IP, you can see two locating pins from the underlying plastic part going through the film and the PE; I'll need to paint them before I finally assemble the IP. That plastic also portrays the back of the instruments. I'll use some 0.2mm lead wire back there. The Blacken-It isn't very consistent. I may yet paint the IP, but at least any paint chipping will be less visible.

 

Thanks for looking! 

[Andrew.S]

Lovely work!