1/18 Scale P-51B 3D Print Build

[JayW]

52 minutes ago, LSP_Kevin said:

A light coat airbrushed on may have been OK, but the volume of paint out of the rattle can would have been too much for the Model Master enamel to cope with.

 

Yes Kevin I think you are right.  The cold weather right now is preventing me from air brushing (I do it in the garage), so I got impatient and used the rattle can indoors. My wing has the enamel on the stars and bars too, so I am a little worried.  But it has held up OK in the past (like the Corsair), although I think I air brushed the Corsair clear coat.  Hopefully careful air brushing on the wing will work.  I do not want to strip that wing. 

 

The fuselage invasion stripes and insignia looked prett ratty anyway.  This is a chance to do better. 

[chuck540z3]

Sorry to hear Jay, but as Kevin mentioned above, lacquer over enamel is always an unhappy ending.  Having had a few disasters myself recently, FWIW, here are my suggestions:

 

1. Take a break from this project for at least a few days, if not a week.  During this time you will come up with all sorts of ideas and fixes, although if you're like me, they will likely come up at 3 o-clock in the morning!  😏
2. Let this setback be an opportunity to make the model even better than it was before.  I'm sure there was lots of small things that bugged you about the paint and other items already, so now you get to fix them all.
3. Move on from Model Master enamels and go with an acrylic lacquer paint, like MRP.  They don't make MM paints anymore- at least not in all of the colors they used to- so you'll need to switch paints sooner or later anyway.  You can spray any clear coat on MRP paint it won't crinkle up like you have experienced.  These paints are also a lot thinner, so you won't get raised edges to the insignias like you do with enamels.
4. As Peter mentioned, why not paint the whole thing at the end, rather than in portions?  I have to believe that paint on sub assemblies is subject to extra scratch marks and damage as you pick them up and move them around.

 

Model on sir!  You've got a killer project well underway here and this setback will be a distant memory in no time.

 

Cheers,

Chuck

[Thunnus]

Don't know what happened since I don't use enamels but the crinkling effect is similar to what I get when I spray a "hot" clear coat (Alclad Aqua Gloss thinned with Mr Leveling Thinner) over an unstable paint base (hairspray treated).  I feel ya Jay but that is the right attitude... a chance to do it better.  Let me know what masks you need and I'll get those out to you again.

[chuck540z3]

19 minutes ago, JayW said:

 

Yes Kevin I think you are right.  The cold weather right now is preventing me from air brushing (I do it in the garage), so I got impatient and used the rattle can indoors. My wing has the enamel on the stars and bars too, so I am a little worried.  But it has held up OK in the past (like the Corsair), although I think I air brushed the Corsair clear coat.  Hopefully careful air brushing on the wing will work.  I do not want to strip that wing. 

 

The fuselage invasion stripes and insignia looked prett ratty anyway.  This is a chance to do better. 

 

 

Jay,

 

Right now it's about 35-40 degrees F. in my garage and I'm still painting in there today, with excellent results.  Get a space heater that directs heat in your paint booth (without a fan that can blow dust) and paint away, especially if you're using acrylic lacquer paints.  A ceramic heater works best with no open flame that could ignite solvents.  Since 90% of my modeling is done during the winter, most of my painting is done in a very cold garage.  The space heater also provides almost immediate curing of the paint when I hold painted parts up to it, so I use a heater in the summer as well, depending on how hot it is.

 

Cheers,

Chuck

[monthebiff]

This could be a blessing in disguise Jay allowing you to fix the areas you weren't happy with such as lifted skinning etc and end up with a much better finish rather than making do. I've never attempted or built anything this big and stick to 32nd scale but I agree with Peter in that get the whole airframe together and then paint as you will get much better and cleaner results and as Chick says change you paint brand, you definitely won't regret it! Keep going as this is one beautiful build and will be absolutely stunning when finished. 

 

Regards. Andy 

[easixpedro]

Tis but a scratch! 
 

seriously, your last pics show you’re already moving past this - and I expect nothing less at this point. You’ve gone from turned parts on a lathe to 3D printing an entire airframe. This is nothing but a speed bump in the road of Jays modeling journey. 
 

I do appreciate you showing the gaffs though, as it makes us realize that you too are human 😊

Onward and upward!

-Peter

[JayW]

So many kind and encouraging comments.  Thank you all.  Still "girding my loins" for try number two.  One of the things I am going to do is to divorce myself from my beloved Model Masters Dark Sea Blue FS15042.  For years now I have used this blue spray paint for my US insignias, and to my eye the hue is perfect.  Not too blue and quite dark.  Up until this point I had not experienced the crinkling failure I just experienced on Cripes.  It is enamel, and I sprayed a Tamiya lacquer clear over it, which is a no-no.  Why now and not before?  Don't know.  

 

At any rate, I will be using a different paint for the insignia, probably lacquer-based.  Bringing me to this question - what is a good proper-colored paint to use?  To date, I have used almost exclusively Tamiya paints, decanting spray cans or using bottles.  I don't get many lift-off issues when painting on the aluminum as long as I use the gloss clear as a primer.  My one foray into Vallejo acrylics was the blue-noser blue and although I like the color I came up with, I will never do that again.  With my clear-coat covered aluminum, it lifts off with the bat of an eye and I have had very many issues with it.  I did a web search and found some folks who like Tamiya sea blue XF-17 in a bottle, and add drops of white until satisfied.  So I bought a couple of bottles.  I don't like it.  It's hardly blue at all - more like dark gray.  I also got some Tamiya US Navy blue AS-8 in a rattle can.  This appears much better - it is "bluer" but not too much.  But it is a lighter shade and I am in the process of adding drops of black to see if I can get something closer to the model Master dark sea blue. 

 

All you master painters out there who have painted great WW2 US insignias - what do you use?    

Edited February 11 by JayW

[Thunnus]

I would recommend trying Mr Hobby Aqueous H326 (acrylic) or Mr Color C326 (lacquer), which are both FS15044 Blue. I used the Aqueous version on my Razorback and Corsair builds...

 

 

[Oldbaldguy]

Personally, I suspect you’re going to have to experiment until you mix up a color you are happy with, perception of the builder being the key here. Were it me, I’d use MRP like everybody says and mix and match til I found something I liked.  Can’t see much future in spraying acrylics on sheet metal, however.  That would be like trying to repaint your car with house paint.  There is a technique I have yet to master concerning super thinned white paint no matter what you use but you likely already know that.

[chuck540z3]

This answer will vary a lot because we all have our paint favorites.  John's recommendations above are all good and I'm sure you will receive some more good paint choices (mine is MRP), so I would check out what your availability is for any of them you are interested in.  There's no point picking a paint line that is hard to buy, which MRP is for me in Canada.  If you live in the US, MRP is readily available from Sprue Bros.

 

Cheers,

Chuck

[JayW]

On 2/11/2025 at 1:13 PM, Thunnus said:

I would recommend trying Mr Hobby Aqueous H326 (acrylic) or Mr Color C326 (lacquer), which are both FS15044 Blue. I used the Aqueous version on my Razorback and Corsair builds...

 

Well John - in addition to trying to gin up my own formula for FS15044 blue with Tamiya colors, and not being very impressed, I looked for the Mr. Color C326.  Without success.  Where do you get these?  

 

On 2/12/2025 at 9:59 AM, chuck540z3 said:

If you live in the US, MRP is readily available from Sprue Bros.

 

Right Chuck - so I ordered some MRP 300 (FS15044) from Sprue.  It's on its way.  Thanks for that!

 

The fuselage paint disaster is for the most part in the rear view mirror, including the emotional damage, although it has put a serious delay in my build schedule.  I wait for stencils from Thunnus, and the MRP blue.  This time I will paint it up right.

 

While waiting, I actually finished the wing painting.  Which was a pretty big deal.  There were minor part breakage casualties, but not paint casualties.  Even though the insignias were painted with the Model Master enamel (applied before the fuselage disaster), they held up to careful and gradual airbrush flat clear final coat.  Whew!! 

 

Some pictures (god this wing is just huge; difficult to take good pics):

 

   

 

 

 

The work area is not easy on the eyes, and for that I am sorry.  The last picture shows well the characteristic droop of the B/C extended inboard leading edge.

 

Details:

 

     

 

Above are lower fuel tank access panels, which are not painted silver.  Supposed to be that way.  And of course the few hundred protruding head fasteners discussed a while back.  These are pretty lumpy panels due to the aluminum skin disbonding issues I had with them.  But the contrasts of the invasion stripes and the flat finish makes it not as noticeable.  

       

 

Above you see the ID lights, now on the RH wing where they belong.  Recall a couple of posts ago I was in a panic because I had them on the LH wing.   This re-location came out more or less to my satisfaction.  The rings are not flush with contour like they ought to be - the penalty I paid for the mistake, but everything else worked out OK.  Note the insignia behaved OK after flat coat.

 

 

Above is the LH lower wing tip, where the ID lights were mistakenly placed on the 3D printed part.  Can you see the three round cover plates?

 

Let's make believe that horrible ID light gaff just didn't actually happen shall we? 

 

 

The guns shown above are finally permanently in place.  Had to wait for painting to be finished.  When I started the wing months ago, I thought the guns and their openings would be trouble.  Nope, they were easy.   Rhino design, 3D printing, and carefully selected tubes of multiple materials. 

 

 

 

Above I show perhaps the worst looking feature of the wings - the landing light.  The aluminum skinning is dreadful, but it's there for good.  No way do I tear it out and do it again.  No way.

 

Two of the aforementioned casualties are the wing tip aft ends.  They are so delicate - this from a couple months ago:

 

 

 

 

You can practically see through the aft end they ar so thin.  

 

Well I failed.  I tried to protect them and I failed.  Both have about .1 inch or so broken away.  I won't show it, it doesn't look that bad.  Until I install the ailerons and then it will look bad.  So I will have to fix them.  I can 3D print the aft portions at a point I will choose later, cut away a matching portion, and CA/epoxy new aft ends on.  MUCH easier said than done.  I think I will do this once the ailerons are installed.  

 

Ailerons?  So I have begun the Rhino work on the ailerons, finally:

 

 

 

 

 

They will be designed and constructed similar to the flaps, which worked out well.  But as I began working the complex inboard end, easily seen with flaps down, I discovered to my dismay that I mislocated the aileron inboard hinge fitting on the wing rear spar!   When will it end???  

 

The hinge fitting is about 0.03 inch too far inboard (full scale that would be about a half inch), which really spoiled the integration of all that stuff on the aileron inboard end.  Sooooo, I got out my magic wand and tweaked some details on the aileron here and there in Rhino and got it to look kinda like the real thing - to a point where few if any will notice.   Maybe I should not have admitted it. 

 

So as I wait for masks and paint for the fuselage repaint effort, I will be concentrating on the aileron now.  I think you will like them once done; lots of work to do to get to that point.  I hope to report good progress on them next post.  Thanks for looking in.  

 

 

 

 

  

 

 

 

Edited February 14 by JayW

[Oldbaldguy]

Not sure I understand your vexation, Jay.  Is it not true that this is your FIRST attempt at a wholly 3D model?  Of course there have been some glitches - it would be scary had there not.  I doubt there is anyone else on this site right now who could have done what you have so far.  This is not to say that the next guy to take on such a project will not blow the rest of our socks off, but dude, honestly.  I’m just happy to be able to tag along in abject wonder as this thing grows out of nothing and frankly could not give two shites if something is .030 whatevers out of whack.  You are building a masterpiece the first time out - own it and revel in it.

[MikeMaben]

[Troy Molitor]

I can't agree more than what the oldbaldguy and Mike have already mentioned above.  

[JayW]

On 2/14/2025 at 6:48 PM, Oldbaldguy said:

Not sure I understand your vexation, Jay.  Is it not true that this is your FIRST attempt at a wholly 3D model?  Of course there have been some glitches - it would be scary had there not.  I doubt there is anyone else on this site right now who could have done what you have so far.  This is not to say that the next guy to take on such a project will not blow the rest of our socks off, but dude, honestly.  I’m just happy to be able to tag along in abject wonder as this thing grows out of nothing and frankly could not give two shites if something is .030 whatevers out of whack.  You are building a masterpiece the first time out - own it and revel in it.

 

This is a really nice thing to say OBG.  Appreciated!  And yes I guess I am guilty of being a perfectionist and maybe even a pessimist in this effort.  Which could annoy some of you.  Understand though that the further I get into this journey, the more pressure I feel.  I am so afraid of compromising what has so far been a long and pretty successful effort.  I am very very vested in this.

 

And let's give credit where credit is due.  Peter Castle (Airscale to us) started this whole thing off on LSP with an effort to 3D print a P-39 in 1/18 scale.  This effort did not go to completion, but since then he has done a wonderful Hawker Sea Fury - not entirely 3D printed but a whole lot.  His P-39 effort was my inspiration to do this 3DP P-51B.  That and some spectacular 3DP parts made for me on my 1/18 F4U-1A. 

 

As for that .03 inch error on the aileron - it was worse than you'd think.  I have had to do some digital design magic to get it under control.   That discovery came at a time where I have had one problem after another.  Am hoping for calmer waters from here on out.  

Edited February 16 by JayW