Heavy Mod - 1/18 21st Century Toys P-47D Razorback

[TwoHands]

Good honest advice all.  And TwoHands - what a marvelous looking saw.  I ought to get it; it might just fit inside the uprights!  That is should I bite the bullet and make a third one.  That requires a night or two of sleeping on it.

They are an extremely handy took once you start using it. Very fine cuts and fast even on thick stock.

[JayW]

Jim Barry said this:

 

"I would support you making another one. The tires are one of the best part of a P-47 and key to this upgrade (as well as being very visible). You'll stare at the mistakes forever but it'll just take a day to correct. Fantastic work, Jay. Rare to get some tricky scratchbuild objects right the first time. Too much to learn."

 

And Jim is right.  I was quibbling because there is so much work involved making another tire.  So I did.  Here are the two tires that will be used for the build:

 

 

 

The third tire turned out so well that I didn't have to hide any bad parts with the weighted flat! 

 

You also see lathe-turned wheel parts.  The hardest ones are done, but I still have the outer rims and the brake drums to go.  It takes a very long time.  Then I whittle on some sheet plastic re-enforcing ribs (6 per wheel), and some other little details. 

 

Just FYI - here's a shot of one of the inner rims being end-milled:

 

 

 

That is how I make the spoke holes.  You would think the machine operations are exact but they are not.  The part is small so the effect of tolerances is magnified, and the various components of the end mill (the post, the cutter, the axle, etc) all deflect just a touch when cutting.  So, in the end I whip out the files and do a bunch of hand work to get it into some shape. 

 

Next post you will see two completed tire/wheel combo's.  

Edited March 9, 2018 by JayW

[Guest]

WOW !!......Harv

[Gazzas]

 That's too fricking awesome for words.

 

Gaz

[Gerhard]

Gaz said it all. 

[richdlc]

wow, this is amazing work. Makes me want to go out and buy a lathe

[Jim Barry]

I felt a little guilty for poking you on this, but thought it was what you were really looking for. You were really just some beads of sweat away from  two amazing P-47 tires forever. Very good! 

[JayW]

I said in my post that the hardest lathe turned parts are done.  Not so - I have managed to fracture two brake drum parts so far (made from acrylic), the last one on the final cut.  But the machine time for the part is around 2 hours (not the better part of a day like the tires).   Stay tuned; I'll get there.

[Out2gtcha]

Great work!  The result of the lathe work is tremendous looking. Id likely screw that up if given a chance for sure. 

[imatt88]

This is going in a museum, right?

[TwoHands]

Stunning work Jay. So glad your documenting this build. One of my favorite things about LSP is seeing the work and ingenuity that goes into a really great build.

[JayW]

OK - it's been about a month for the tire/wheel project.  I have about a week to go, but I have something good to show you.  First, when this P-47 was going to be a razorback (see my first posts), the wheels were going to have wheel covers, which would have greatly simplified the scratch building of the wheels.  For those of you not that familiar with P-47's (any of you out there?), this picture shows wheels with wheel covers:

 

 

 

Then, I changed to the bubble-top, specifically Major Eagleston's aircraft - here is a wartime picture:

 

 

Is that a cool image, or what?  Note this aircraft lacks wheel covers.  So be it.  Now I have to create the spoke patterns, and even more - since you can easily see inside the rims, I have to create some level of detail in there.  

 

The wheels and drum brakes were apparently supplied by Bendix.  And drawings are not available to me.  But I found a fabulous cross section picture in the Erection and Maintenance manual:

 

 

That is almost as good as the engineering drawings.  It has reams of information I can use.  And use it I did.  You have already seen the beginnings of the wheel fabrication effort.  Let's see some more:

 

You have seen this picture before:

 

 

I combined two of the acrylic pieces and one of the brass pieces and got this:

 

 

But you also see 18 nuts (Meng again) which in real life attach the brake drum to the wheel, the beginnings of re-inforcement ribs (one lying next to the wheel), and the axle housing.  All that stuff is well-defined in that cross-section.

 

With internal re-inforcement complete, it looks like this:

 

 

 

That was a big PITA.

 

The outer rim and brake drum were next:

 

 

The brake drum (on the left) is the third try after I fractured the first two.  The little stiffening elements on the rim on the right are chunks of .015 by .040 strip, each epoxied into place and then trimmed flush.

 

Slide one into the other and you get this (should look familiar to P-47 experts):

 

 

The last lathe-turned piece was the axle cap.  Here is one with machining almost done:

 

 

Next post I present the finished tire/wheel.

Edited March 14, 2018 by JayW

[JayW]

Then came lots of painting and weathering.  Here is the finished result:

 

 

 

 

 

 

Ha!  I sure like my diamond tread!  That's the reason I took a break from the fuselage in the first place- to see if it could be done.  Note I have added a putty bulge to the bottom of the tire to simulate weighting. 

 

That is the LH wheel and tire.  Tell me what you think.  Now for the RH, which is not too far behind.  Can somebody give me suggestions how to add dirt to the tire and look convincing?  I got some dirt from the back yard and smeared it on, but it falls off, and I am afraid to spray clear paint over it.  Tire looks too pristine - must address this.

 

Next post I will show the other wheel/tire.  Then it's back to the fuselage!

Edited March 14, 2018 by JayW

[TwoHands]

Lookin' good Jay!

[Guest Maxim]

That looks really good! Really clean work on the wheels. What about using some oils on the tires? At least you could wipe it off and it'll give you plenty of time to work the paint until you have the effect you want?

Edited March 15, 2018 by Maxim