The Pitts Special 48" Edition Printer Settings.

Filament:

I originally designed this model to be printed from standard PETG filament. This is what I used for my prototype. I have since then have available to me the newer style Bambu Labs printers with an enclosed build volume. If you happen to have access to a printer like this, then I would suggest taking a look at ABS. The reason for this is that ABS is simply far more heat tolerant, and stronger overall in my opinion. I used to avoid ABS like the plague because I found it difficult to work with and admittedly stinky, but the Bambu printers have surprised me with flawless and easy results.

What I don't recommend for this model is PLA. Unfortunately, for traditional iron on covering you will need a filament with a higher melting point. I also find PLA to sometimes be a bit brittle.

Print Settings:

Most of the parts are designed to be printed at 100 percent infill. They are designed to be very thin, and only have printed material where it is needed for strength. The parts mostly lay flat on the build plate as well. In only a few cases you may have to add support material.

Lightweight PLA:

I only used lightweight PLA when printing the wheel pants and cowling. I subsequently reinforced them with a very lightweight weave of fiberglass cloth from the inside. 4 ounce cloth is what is typically sold at auto parts stores. It will work, but you can get much lighter weight cloth than this at boat stores. Alternately you can check out aircraft spruce and supply for anything composite related that you would ever want. I impregnated the glass with a UV curable fiberglass polyester resin. The product of my choice is Solarez. Make sure that you are choosing a sanding or finishing resin and not a laminating resin. Laminating resins will remain tacky at the finish for the purpose of accepting another coat. You wont be able to sand and finish this unless you use a wax or styrene additive. Here's an amazon link: https://amzn.to/4lvbKHy

The great thing about this resin is that you can work with it all you want until you are ready for it to start curing. Paint the weave carefully and ensure that the weave is fully filled, but try not to leave any standing puddles of resin. It only adds weight. When you are happy with your results, they claim this can be curable by the Sun, but I always just carefully hit it with a UV light. It sets up incredibly fast - like in a few seconds fast. One suggestion is to only very briefly hit it with a UV light at first as the resin heats when curing. If you go for full cure immediately, you could end up with a warped lightweight PLA part.

For finishing the outsides, I paint the parts with a coat of ABS like resin designed for SLA printers. This resin is ideal for filling layer lines. Again, you can paint to your hearts content until you are absolutely happy with what you have done. I then hit it with the UV light again, and it hardens almost immediately. I will then wipe the part with an alcohol soaked paper towel, and check the part. If it needs another coat then simply reapply. Finally the finish is highly sand able with 220 grit paper to make a perfect substrate for painting. The finish I used on my prototype was simply a rattle can of red spray paint. . It came out beautiful and matched the Ultracote covering color perfectly.

Conclusion:

That's pretty much it for printing.