FM-2 Conversion of Trumpeter F4f-4 kit.

[LSP_Ray]

Do to there being interest lately on the boards, I have decided to get back into production of masters for a new FM-2 conversion for the Trumpeter F4f-4 kits. I started this over a year ago, then a series of medical issues caused me to put it on hold. But with this #$%^& virus going on, I am forging ahead.

Short overview

As most of you know, the FM-2 was a lightened and higher-powered version of the F4f-4, built by Easter Aircraft. Grumman was focused on building Hellcats, while Eastern stuck to the Wildcat to be used on the growing numbers of escort carriers being built. The FM-2 ended up being the most numerous of Wildcat variants by far, with over 4000 built, including 350 built for the FAA. It was called the Martlet VI at first, but that was soon officially changed to Wildcat VI. With the numbers built, and differing camo possibilities, it is a wonder Trumpeter didn't offer this version themselves.

Major changes to the F4f-4:

  Engine changed to R1820. This included a new, shorter, cowl and a longer accessory section(just to make things difficult).

  Exhaust outlets changed to 'jet' style to add that little bit of thrust, the individual exhaust pipes exiting through four different points around the cowl.

  Armament reduced to four 0.50 cal MG's with increased ammo load (similar to F4f-3's).

  Wing oil coolers removed, replaced by a large oil cooler in the accessory area.

  Tail and rudder enlarged for better horizontal stability due to the increased torque of the R1820.

The Trumpeter kits

As everyone has probably heard, Trumpy's first release was a pretty nice mess. Supposedly Stevens Imports refused to buy them until they were fixed and so Trumpy did a (partial) re-tooling. Here is the original Trumpeter kit over a set of plans by J. Temma, blown up to 1/32nd scale. Don't mind the short tail, I sawed it off!:

You can see the sway down the spine and the woefully shallow area ahead of the canopy. BTW, here is an easy way to know if you have an early or re-tooled Wildcat:

The original tooling is the only version that had molded in ribbing behind the cockpit.

Here is the re-tooled version against the same drawing:

 

Much better! It is a little short down the spine, but much more livable. They also re-tooled the wings, mainly the surface detail including riveting and areas around MG access panels and oil coolers. But they didn't re-tool everything. Here is two shots of the firewall in the old tooling:

See how well the firewall fits top and bottom, and how the cutout for the wheels fits the opening. Here is the new tooled kit:

Deeper fuselage, but same part. Now there is a gap top and bottom, and the wheel cutouts don't match the openings. What also worries me is that I wonder about how the fit of the landing gear structure fits in the new tooled kit. One post is in the same place, but the structure that sits at the bottom now is lower. I am going to have to take a look at that, and really, the whole firewall needs to be fixed. I might end up with some parts to do a F4f-3/4 fix as well as the FM-2. More work for me. 

[LSP_Ray]

OK, a year ago I started with the tail and rudder to get a feel for the project and get something done to feel motivated.

I used sections cut from multiple kits to keep as much of the original surface detail. I am actually using parts from the old-tooled kit (not much though), a new-tool F4f-4, a F4f-3, and a SBD-5 kit. It is not totally finished, but there isn't much else to do: fill in one of the hinge points, some rivet and other detailing.

[LSP_Ray]

So now, I am going on to some of the more difficult parts, starting with the cowling and the extended accessory area and exhaust indents.

Luckily, the SBD-5 also used the R1820 and the Trumpy cowling is nearly an exact match to the drawings.

 

Looks a little large here, but actually it is a bit undersized in diameter, but not much! Actually, if I was just doing a one-off for myself, I could easily make this cowl fit. But I need to finesse it to use it as a master. I also need to add a section to replace where the MG outlets were on the SBD. But before I do that I need to rework the accessory area to properly fit the cowl.

Here you see I have cut off the nose to the back of the first row of rivets and have started adding filler pieces to back areas I need to carve exhaust outlets in. I figure three added layers should be enough.

[Kagemusha]

Great to see you make a start on this Ray, please put me down for a set. 

[Troy Molitor]

Love this topic Ray.  Thanks for the motivation moving forward.   I’m impressed.  

[LSP_Ron]

Nice!

[LSP_Ray]

45 minutes ago, Troy Molitor said:

Love this topic Ray.  Thanks for the motivation moving forward.   I’m impressed.  

Thanks, Troy! I think your sander is going to get a good workout on this one!

[John1]

Following with a great deal of interest.   I’d love to build an FM-2!  

[LSP_Mike]

Nice start Ray. 

[phasephantomphixer]

Another Trumpeturd tackled to submission. That firewall shud get real chain or PE while at it. Not to put gas on the fire...

[MikeMaben]

 

 

                                             

[Troy Molitor]

I always liked the lines of the FM-2.  I always wanted to pick this kit up but was also worried about getting the earlier example with the screwed up fuselage.  Now I know what to look out for.  Thanks.  

 

P.S.

Sand away!  The extra sanding packets I can get you for $7.00.  I had mine out last night going to town on my PCM Macchi 202.  Lol. 

[Derek B]

Loving your work Ray  (I have always liked the Wildcat; I wonder how the Revell kit compares shape-wise?).

 

Derek

[LSP_Ray]

8 hours ago, phasephantomphixer said:

Another Trumpeturd tackled to submission. That firewall shud get real chain or PE while at it. Not to put gas on the fire...

PE would be the bomb, but the added expense of doing PE for the conversion I don't know i it would be worth it. You can barely see the chain once everything is together I fear. I may at least improve the look, though. Got a couple of ideas. First, need to create a part that actually fits. 

 

1 hour ago, Derek B said:

Loving your work Ray  (I have always liked the Wildcat; I wonder how the Revell kit compares shape-wise?).

 

Derek

I think the Revell kit is pretty good shapewise, but details on the whole are much better on the Trumpeter. There actually was a FM-2 conversion long ago, in vac I think by Horizon Conversions? But all you got was a new nose for the cowl deleting the inlet, and a new vac tall tail. So about 20% there. I am hoping to get about 90% there, plus giving you instruction on converting the wings, which would consist of making 4 new thin plates, and sanding off two MG's and adding the correct panel lines in their place. The four plates would be nice in PE but considering I don't have the drawing program or access to a PE producer, it would be as I said before an extra cost and a lot of time, unless I had a volunteer *cough* AIrscale *cough*. Considering it would be rather simple to create the plates with thin plasticard, it would be well within the capabilities of anyone going to do this conversion.

That is a ways in the future, though. I get these major steps done first.

[Derek B]

4 minutes ago, LSP_Ray said:

PE would be the bomb, but the added expense of doing PE for the conversion I don't know i it would be worth it. You can barely see the chain once everything is together I fear. I may at least improve the look, though. Got a couple of ideas. First, need to create a part that actually fits. 

 

I think the Revell kit is pretty good shapewise, but details on the whole are much better on the Trumpeter. There actually was a FM-2 conversion long ago, in vac I think by Horizon Conversions? But all you got was a new nose for the cowl deleting the inlet, and a new vac tall tail. So about 20% there. I am hoping to get about 90% there, plus giving you instruction on converting the wings, which would consist of making 4 new thin plates, and sanding off two MG's and adding the correct panel lines in their place. The four plates would be nice in PE but considering I don't have the drawing program or access to a PE producer, it would be as I said before an extra cost and a lot of time, unless I had a volunteer *cough* AIrscale *cough*. Considering it would be rather simple to create the plates with thin plasticard, it would be well within the capabilities of anyone going to do this conversion.

That is a ways in the future, though. I get these major steps done first.

 

Thanks Ray - sounds good (good luck with this venture - I fully understand and appreciate the type of work you are doing).

 

Best regards

 

Derek

Edited April 27, 2020 by Derek B