Airfix 1:24 Grumman F6F-5 - One Hell of a Cat!

[CraigH]

17 hours ago, Westland WhirlWill said:

Just found this project, awesome work on that engine and cockpit Craig! 

Thank you so much. It's getting there

[CraigH]

Right so today it's on to the thorny subject of the oil system. As chuck540z3 says on his build, there's a complete dearth of pictures of the rear of the engine. Chuck posted this image and asked "where is that gizmo at the bottom where all the oil lines go?"

 

It's the oil cooler but all the oil cooler assembly sits behind the firewall so presumably all the oil pipes from the oil tank and the engine which are in front of the firewall have  to get through there somehow.

This is a blow up of the oil cooler assembly. I guessed from the bit of cut off text in the diagram above that it was a Harrison oil cooler assembly

The "gizmo" Chuck referes to is part of the cooler assembly and is actually a thermostatic valve for the hot oil. If the oil is cool enough already as it enters the cooler the valve stays open and it bypasses the cooler ant heads straight back to the oil tank.

If it's too hot, the valve closes and the oil is forced through the cooler to cool down before heading to the oil tank.

Here's the gizmo exploded

Again, since this is bolted to the oil cooler, it must lie behind the firewall. And all the pipes have to make their way through but there's no pictures of it!!! 

I trawled the internet, youtube and anything else as well as trying to reconcile different drawings of the oil system such as this one

 

Then this morning I found a video on Youtube of the restoration of an f/6/f-3 /BuNo 25910 and blessed be here were stills of the whole firewall assembly!!

It now becomes crystal clear that the oil pipes attach to the fittings to the right of the front of the oil cooler then attach to the "gizmo" or thermostatic valve behind it.

In other words, all I have to do is fashion the fittings and fasten my oil lines to them. The oil cooler assembly is invisible behind the firewall so I've nothing to scratch build or invent except for the little fittings which are holes and styrene rod, PHEW!!!!

So, tomorrow I can get on with that. In between tearing my non existent hair out I also managed to get the prop about done today as well....Happy

[chuck540z3]

7 hours ago, CraigH said:

In other words, all I have to do is fashion the fittings and fasten my oil lines to them. The oil cooler assembly is invisible behind the firewall so I've nothing to scratch build or invent except for the little fittings which are holes and styrene rod, PHEW!!!!

So, tomorrow I can get on with that. In between tearing my non existent hair out I also managed to get the prop about done today as well....Happy

 

Whoa Craig, I think you probably have it wrong, so I have mixed a few of your pics above with a few diagrams I have, which I think will prove my point that the "Oil Cooler Shutter" (OCS) is in front of the wall and very visible- and not buried behind it.  BTW, these pics are excellent and will help me with my build, so thank you for finding them!

 

First let's look at the assembly next to that big front vent pipe you show above, which we'll call the "Front Assembly" (FA), for lack of a better description.  You can't really tell where the wall is in this diagram.

 

 

Now a few more diagrams, which indicate that the FA is indeed in front of the rear wall.  First the one I used in my build thread.

 

 

And a much better one, that is a bit clearer and more realistic.  Note how the 3 pipes are tight to the OCS and attach to it.

 

 

 

One more....

Now the pic of the real deal.  You can't see the FA or the OCS, because they are completely missing.  It seems clear to me, that the OCS fits onto that pipe on the right, where the oil goes through the radiator behind the wall, but the OCS is in front of the wall when installed.  Similarly, the big circular vent pipe is missing as well.  Make sense?

 

As for the 2 pipes to the right of the OCS, I have no idea what they are for, but they don't seem to be oil cooling related and they don't match the OCS diagram at all.  Electrical conduits maybe?  Another interesting thing is the control arms for the vent doors below, which are on Part K38, just above the big circular vent.  This part collides with the OCS I made, because they are more vertical on this part vs how they look in this pic.  I can just bend them out now, knowing that they could be accurate for a Hellcat under maintenance, which is my goal.

 

 

Cheers,

Chuck

 

 

Edited February 4, 2022 by chuck540z3

[CraigH]

1 hour ago, chuck540z3 said:

 

Whoa Craig, I think you probably have it wrong, so I have mixed a few of your pics above with a few diagrams I have, which I think will prove my point that the "Oil Cooler Shutter" (OCS) is in front of the wall and very visible- and not buried behind it.  BTW, these pics are excellent and will help me with my build, so thank you for finding them!

 

First let's look at the assembly next to that big front vent pipe you show above, which we'll call the "Front Assembly" (FA), for lack of a better description.  You can't really tell where the wall is in this diagram.

 

 

Now a few more diagrams, which indicate that the FA is indeed in front of the rear wall.  First the one I used in my build thread.

 

 

And a much better one, that is a bit clearer and more realistic.  Note how the 3 pipes are tight to the OCS and attach to it.

 

 

 

One more....

Now the pic of the real deal.  You can't see the FA or the OCS, because they are completely missing.  It seems clear to me, that the OCS fits onto that pipe on the right, where the oil goes through the radiator behind the wall, but the OCS is in front of the wall when installed.  Similarly, the big circular vent pipe is missing as well.  Make sense?

 

As for the 2 pipes to the right of the OCS, I have no idea what they are for, but they don't seem to be oil cooling related and they don't match the OCS diagram at all.  Electrical conduits maybe?  Another interesting thing is the control arms for the vent doors below, which are on Part K38, just above the big circular vent.  This part collides with the OCS I made, because they are more vertical on this part vs how they look in this pic.  I can just bend them out now, knowing that they could be accurate for a Hellcat under maintenance, which is my goal.

 

 

Cheers,

Chuck

 

 

Ah now, pictures 3 & 4 in your reply change everything. I've never seen those before, where did they pop from ? 

If you're right, what I saw as the from mesh of the oil cooler assembly is now clearly the rear of it and the whole assembly bolts on the front of the firewall. Looking at it, that has to be the case as, on closer inspection, that strut across the cooler grille appears on the Airfix kit as the rear face of the cooler but they put the whole assembly BEHIND the firewall. A mistake, For ease maybe?.. In a kit of this complexity with over 500 parts, I'd have thought they could've been more accurate.

 

More studying needed, just when I thought I could crack on.

Thanks for the new pics Chuck, really helpful

[CraigH]

1 hour ago, CraigH said:

Ah now, pictures 3 & 4 in your reply change everything. I've never seen those before, where did they pop from ? 

If you're right, what I saw as the from mesh of the oil cooler assembly is now clearly the rear of it and the whole assembly bolts on the front of the firewall. Looking at it, that has to be the case as, on closer inspection, that strut across the cooler grille appears on the Airfix kit as the rear face of the cooler but they put the whole assembly BEHIND the firewall. A mistake, For ease maybe?.. In a kit of this complexity with over 500 parts, I'd have thought they could've been more accurate.

 

More studying needed, just when I thought I could crack on.

Thanks for the new pics Chuck, really helpful

Having had a few minutes to look at the "new evidence" LOL! (I got the post at 5:45am and knee jerked, oh the joys of the international date line!)

I'm back at my original theory, with evidence to back it up I hope. Work calls but i'll spill the beans on my return

 

[CraigH]

3 hours ago, CraigH said:

Having had a few minutes to look at the "new evidence" LOL! (I got the post at 5:45am and knee jerked, oh the joys of the international date line!)

I'm back at my original theory, with evidence to back it up I hope. Work calls but i'll spill the beans on my return

 

Right, work over for a while, let's get down to business!

• So, looking at the new picture Chuck posted
•  

Looking at the header on the page scan suggests this is taken from an actual un crating and maintenance manual the number AN 01-85FB-4 suggests it is. So, it should be accurate

Where I've got issues is that the black jagged edge around the oil cooler assembly suggests this is a cutaway diagram ie the firewall is cut away to expose the oil cooler assembly sitting behind it. The connections are transparent further suggesting that the oil cooler sits behind them.

 

• The picture of the firewall actually shows the oil cooler assembly front. The cooling cannister is a complete assembly, you can't take the top and bottom off it as here. 

 

What Chuck refers to as the picture (PIC. 2)with the front cannister assembly missing is actually showing the front OF the cannister in it's proper position

The fittings Chuck says might be for electrics can't be true as there is clearly a drain of some sort coming off of the lower one. Moreover a similar setup shows in this diagram (PIC. 1) and is marked as a drain.

My belief is that the two right hand connections painted in primer on PIC. 2 are the return pipes for the oil to go back to the tank after having been through the cooler, one to feed the cooler oil to the bottom of the tank and the other to the top as shown in this diagram with a cutaway of the oil tank interior

 

The dark inlet pipe to the left of these two is for the hot oil from the engine to enter the oil cooler.

 

• From a suppositional point of view, Airfix have produced a superb kit. It's very accurate. They've even included the oil cooler assembly if not the thermostatic valve assembly, F37. I cn't believe they'd then locate it wrongly.

 

• Lastly, Where the hell does it fit if it's in front of the firewall? The supercharger air intake runs right to the front of the firewall, there's nowhere for it to go if, as Chuck believes, PIC. 2 shows the firewall with the oil cooler missing.

 

 

 

[chuck540z3]

2 hours ago, CraigH said:

My belief is that the two right hand connections painted in primer on PIC. 2 are the return pipes for the oil to go back to the tank after having been through the cooler, one to feed the cooler oil to the bottom of the tank and the other to the top as shown in this diagram with a cutaway of the oil tank interior

 

The dark inlet pipe to the left of these two is for the hot oil from the engine to enter the oil cooler.

 

• From a suppositional point of view, Airfix have produced a superb kit. It's very accurate. They've even included the oil cooler assembly if not the thermostatic valve assembly, F37. I cn't believe they'd then locate it wrongly.

 

• Lastly, Where the hell does it fit if it's in front of the firewall? The supercharger air intake runs right to the front of the firewall, there's nowhere for it to go if, as Chuck believes, PIC. 2 shows the firewall with the oil cooler missing.

 

LOL, now you've got me second guessing myself, but I am equally convinced- although a bit shakier this time- that I am right with these thoughts:

 

• Forget about Part F37 being the Front Assembly (FA).  It's just there to provide the detail required when you view the cooler radiator from the back, with the bottom door in the open position.  The FA is within the "supercharger air intake", which is not a supercharger intake at all, but merely a cooling duct to the oil cooler radiator.
• Note that the 2 pipes on the right of the Oil Cooler Shutter (OCS) are literally on top of each other (touching each other?) and bend directly over the top of the OCS and tight to it, not beside it like the pipes to the right on the real deal, which are too far apart.  This is what caused me all the grief of trying to replicate something similar, because I ran out of room to fit the pipes between the FA and the engine support.
• The OCS appears to be directly beside the FA and likely attached to it.  The entire OCS, including pipes, is approximately 1/3 of the size of the FA.  If those pipes to the right of the FA on the real deal are part of the OCS, the OCS would be huge- maybe 2/3's the size as the FA or more and there's no room for such a thing right of the FA.

 

You may be right Craig while I believe I'm right, but without pics I don't think either of us will know for sure.  It's also possible that there were 2 types of oil cooling canisters, one in front of and one behind the wall.  The pic of the real deal strongly suggests that those pipes are possibly oil lines, but they don't match the schematics at all, because they are too far apart.

 

There is a pic of the real deal out there somewhere that can put this debate to rest.  We just need to find it.

 

Cheers,

Chuck

 

 

 

 

Edited February 4, 2022 by chuck540z3

[CraigH]

1 hour ago, chuck540z3 said:

 

LOL, now you've got me second guessing myself, but I am equally convinced- although a bit shakier this time- that I am right with these thoughts:

 

• Forget about Part F37 being the Front Assembly (FA).  It's just there to provide the detail required when you view the cooler radiator from the back, with the bottom door in the open position.  The FA is within the "supercharger air intake", which is not a supercharger intake at all, but merely a cooling duct to the oil cooler radiator.
• Note that the 2 pipes on the right of the Oil Cooler Shutter (OCS) are literally on top of each other (touching each other?) and bend directly over the top of the OCS and tight to it, not beside it like the pipes to the right on the real deal, which are too far apart.  This is what caused me all the grief of trying to replicate something similar, because I ran out of room to fit the pipes between the FA and the engine support.
• The OCS appears to be directly beside the FA and likely attached to it.  The entire OCS, including pipes, is approximately 1/3 of the size of the FA.  If those pipes to the right of the FA on the real deal are part of the OCS, the OCS would be huge- maybe 2/3's the size as the FA or more and there's no room for such a thing right of the FA.

 

You may be right Craig while I believe I'm right, but without pics I don't think either of us will know for sure.  It's also possible that there were 2 types of oil cooling canisters, one in front of and one behind the wall.  The pic of the real deal strongly suggests that those pipes are possibly oil lines, but they don't match the schematics at all, because they are too far apart.

 

There is a pic of the real deal out there somewhere that can put this debate to rest.  We just need to find it.

 

Cheers,

Chuck

 

 

 

 

Just arrived from a friend....case closed LOL. If only we'd had it weeks ago. Official US Navy pilots guide from 1946

We know now. It can only make life easier. Enjoy your holiday Chuck. I'm off the pub for a Friday night pint

[chuck540z3]

It doesn't get clearer than that Craig!  Thanks for finding this, because I was concerned for obvious reasons.  In my thread somebody pointed out a Hellcat build where the modeler went to great lengths to get everything as close to accurate as possible.  He put the cooler valve in front of the firewall as well, so I'm in good company.

 

Thankfully I can still make these changes easily, although I have some holes to fill before I create new ones.  With your pic of the real deal above, I replicate the pipes more easily.

 

Cheers and again thank you,

Chuck

[CraigH]

1 hour ago, chuck540z3 said:

It doesn't get clearer than that Craig!  Thanks for finding this, because I was concerned for obvious reasons.  In my thread somebody pointed out a Hellcat build where the modeler went to great lengths to get everything as close to accurate as possible.  He put the cooler valve in front of the firewall as well, so I'm in good company.

 

Thankfully I can still make these changes easily, although I have some holes to fill before I create new ones.  With your pic of the real deal above, I replicate the pipes more easily.

 

Cheers and again thank you,

Chuck

No probs Chuck. If you want a copy of the whole manual dm me and I'll fire it across. There's quite a bit of useful stuff in there that us Poirot type detectives can relate to

[CraigH]

So now the oil system quandry is sorted, I can get of with tarting up the firewall a bit. Bit of murk and dirt to start. Zinc chromate yellow base then some Tamiya clear orange heavily diluted with IPA about 9 :1 and sprayed to represent a bit of heat damage. Engine grime next again heavily diluted and lastly fresh engine oil a thin sheen covering most parts. Hopefully looks better already.

I also realised the interior section below the firewall also needs to be Zinc Chromate Yellow so that was sorted as well.

Next up are the wires for the control surfaces and the pipework going out from the firewall to the wings. One pair are to deliver fresh air to the cockpit, not sure on the other pair.

Anyway, I have a pathological hatred of kit plastic pipework and wiring.

 

My original thought were wo separate the horrid plastic pipes from the control surface wires underneath and use the control wires while making new pipes. But the wires looked messy and then when I got this image of the firewall I realised the lot had to go

 

So I fashioned new wires and spacers from sheet styrene and 0.6mm aluminium wire. Sprayed black, hopefully they look better than the kit plastic. The pipe work was easy. The thinner pipe from 1.2mm aluminium wire and the thicker from 2mm both sheathed with shrink tubing and dunked in boiling water for a few seconds then shaped and fitted. This picture also gave eb the colour of the little black box on the upper right and the fact that there's an electrical wire dropping out of it. In fact, this pic gives loads of wiring and pipework I hadn't seen which, with some other photos should mean i can get most of the important wires pipes and other gubbins needed and which Airfix don't include. I won't put it all in though, just enough to give it a busy feel. So, this is the firewall to date. As ever, thanks for looking

[airscale]

that looks amazing Craig - half the fun for me is finding out and learning about the airframe, so good job on all the research on the oil cooler

 

..by the end you will know every inch of the big Cat

 

Peter

[CraigH]

1 hour ago, airscale said:

that looks amazing Craig - half the fun for me is finding out and learning about the airframe, so good job on all the research on the oil cooler

 

..by the end you will know every inch of the big Cat

 

Peter

Thanks Peter. Got a nice camera now so will be posting some better pics of your awesome cockpit setup

[CraigH]

5 hours ago, airscale said:

that looks amazing Craig - half the fun for me is finding out and learning about the airframe, so good job on all the research on the oil cooler

 

..by the end you will know every inch of the big Cat

 

Peter

Thanks Peter. Have a better camera now hoping to get some better pictures of your awesome cockpit upgrade on soon

[CraigH]

On 2/6/2022 at 5:27 PM, CraigH said:

Thanks Peter. Got a nice camera now so will be posting some better pics of your awesome cockpit setup

As promised here are some better pics (although I'm no photographer) of the brilliant cockpit enhancements from Peter at Airscale. I'll be fitting the windshield tomorrow so wnted some pics for posterity while it's still relatively open 

I've just got a commission for a 1:32 Lanc and I'm hoping the Border model will be out before I buy one, although I'm not holding my breath on that one. If it is, I'll be banging on his door hoping he's producing one for that. Otherwise HK Models it is. Anyway, here's the pics: