cockpit alligator effect

[seaviper]

I have alligatored two cockpits. One on my T-28 last year and today my T-45. If I re-paint the Goshawk in the future then I will fix this cockpit. In the meantime I bought another one to replace it.
I have some thoughts on how to prevent this. But I would like to know what others do to prevent this from happening.


BTW when you fly a full scale plane with a clear canopy you quickly realize how hot they can get inside. Especially if you come from the Cessna community.

[Grossman56]

I have the same trouble with every one piece canopy, but my retractable canopies, such as the ones on my P-51D's don't 'gator up' so I'm thinking it has more to do with ventilation and the color of the cockpit itself.
There has been some mention of drilling an inconspicuous hole in the canopy, but I'm not sure how much ventilation that would add. The FMS P-51 is open to a large extent, on the bottom so there is an air flow through there. That may be a better way to ventilate.

Grossman56

[T-CAT]

I have alligatored two cockpits. One on my T-28 last year and today my T-45. If I re-paint the Goshawk in the future then I will fix this cockpit. In the meantime I bought another one to replace it.
I have some thoughts on how to prevent this. But I would like to know what others do to prevent this from happening.


BTW when you fly a full scale plane with a clear canopy you quickly realize how hot they can get inside. Especially if you come from the Cessna community.

The primary thing I do to help prevent the foam gator effect is keep the plane in the shade when I'm not flying, since shade is available at the field I fly at most times. That works well, but the cockpit can even get the gator effect from sun exposure during the short flights and taxi backs depending on the days temperature.

Most often, I'll still take the canopy off when I get the plane, strip the paint off of the cockpit area, brush on coats of 30-60 min epoxy (I'll sand it when fully dry if the epoxy is too uneven in spots), and paint it when fully dry. I'll make sure not to epoxy or paint the area where the canopy would glue to the foam. It seems to be holding up so far, at least better than not having that coating on it. Then again, I still keep a conscious effort not to have my planes in the sun for too long, so I may not be the best example of whether this works perfectly or not.

Sometimes I also cut part of the cockpit foam floor (or other areas that aren't easily visible) out near the pilot in hopes of getting some ventilation and reduce the temperature within the canopy.

[seaviper]

Yeah I do all that stuff too. I know that a good coat of lightweight spackle (drywall patch and primer ) works well. I also used to drill small holes in the canopy. That is more to keep the canopy from popping a glue joint or expanding.
Today I had the T-45 outside under cloudy skies. Then, the sun came out for just a few minutes. Next thing you know the cockpit is baked.

When I go to the field and others are there (like the weekend), I take my 12x12 easy-up. I also take care not to put the bird in the sun for long. Otherwise during the week I can use our little metal shelter for shade. Just trying to see what everybody else does to curb the gator effect.

I may try a combination of sanding, drywall patch, and paint. I may use some paper also on the dash and seats. This T-45 will get a repaint into the Marines scheme unless Motion comes out with one of their own. At any rate, It's not getting painted till winter sets in.

[agedflier]

There are two options I have used.... 1. thin plastic card (model railway supplies) and 2. used cardboard cartons(cereal packs)... Method.....sand the surface to make a good bond... Cut the part/parts you need...test fit and the glue and paint....Result....Gator no more....Hope that helps.

[seaviper]

thanks agedflier...I think I am going to use that method when I get to re-painting again this winter.

[wrongroad]

G'day seaviper,
I have done something similar to the idea of agedflier only I use 1mm balsa.
The turtle deck area on the FMS 1400mm series Mustangs [D's] is prone o the gatoring effect and I simply made a new deck and boxes from the 1mm balsa, filled it with light weight filler and painted it the appropriate colour. It simply glues on top of the existing deck after you remove the boxes. Sand around the edges to flush fit and the canopy will fit like a glove.
No more dramas.
I have done the same with my FMS 1400mm T-28 Trojans in between the cockpit areas and the dash area in the front cockpit. This is a little harder as the compound curves and angles make the sheeting harder to get right in one piece. This is when I use cardboard to make templates until I am happy with the fit and then make the final item. Throw away all the 'dud' templates and keep the one that is right. For later of course. You know, the next model you buy!!
It is a project that take some time but it is well worth it. I fly in temperatures of plus 38*C all through summer and now have no drama in the cockpit.
Hope this gives you at least, one more idea!
Regards and respect
Daryl

[seaviper]

Thanks Daryl. I have repainted birds before and also know that simply using drywall putty and painting it also works. Thanks for the ideas. I will be repainting a couple birds this winter and I will probably use all the ideas listed above. Mostly I use the putty or card stock solution. But I have tons of balsa and I do use it for various things. It works great for stiffening a foam control surface. And it adds very little weight. Anyway, thanks guys.

[Pauly]

Seaviper, instead of using a cereal box you may be able to a playing card. Just a thought! I have never used one for that, but have for many other things. I know you could paint it the color of your choice.