New member with a Stearman PT-17 build

[MikeCallender]

Hello All,
I am returning to Balsa Wood Airplanes after a 45 year break. I just completed two aircraft (Corsair and SE5a) and learned a lot of lessons. Mostly, I learned I have so much more to learn. I am starting on a Stearman PT-17. Unfortunately, it is not a laser cut model, so removing the parts from the balsa wood panels is taking a long time. I am looking for any hints or tips. My intention is to fly this model with the rubber band (not ready to upgrade to anything else). My other two models flew poorly, but it was fun none the less. I hope everyone is staying away from COVID-19 and look forward to hearing from you.

Mike Callender

[kittyfritters]

Mike,

Welcome back to the dark side!

Been a long time since I did a die cut model, but if I remember correctly the best way to get the parts out is to sand the back side of the sheets before trying to remove the parts.

Hope this helps,

KF

[MikeCallender]

Thank you, I did but not follow the recommendation by Guillows (sand to 1/2 the thickness). I was a little afraid to sand that much, what do you recommend?

Michael

[kittyfritters]

Thank you, I did but not follow the recommendation by Guillows (sand to 1/2 the thickness). I was a little afraid to sand that much, what do you recommend?

Michael

Michael,

Is that what they said? I don't think you should have to go that far. The only time I have had to go that far was with a 500 Series Bf109 that had 27 lb/cubic foot balsa. (The low end of the red oak range!) I had to run that through between a drum sander and a fence on my drill press. Needless to say the parts came out of the sheets with no trouble. It was interesting building a Guillow's kit with 1/32 inch balsa.

Any way, you only have to sand until the parts come loose. Sometimes you have to give them a little nudge with an Exacto knife.

Again, hope this helps,

Howard

[MikeCallender]

Howard & KT,
Thanks, I resanded the panels that were left and I had a much easier time getting the framers and other pieces out, but I was not even close to "popping" them out. (N.B. yeah no belt sander here, basically I have few tools or experience, so this effort is a distraction from good wine). While it is mostly likely my ineptitude, I am not so sure. Is there a technique you could share? I had to trace each one with an Exacto knife, especially the 3/32 panels. Particularly the notches for the stringers. How do you make sure you are even and consistent with depth? I have used a small file to try and ensure I have the right depth, but I must admit, it feels like more work than I should be doing.
However, pressing ahead, I have the pieces out and have started the build, I am working slow and re-read the instructions, but it goes without saying the instructions are perfect for those who know what they are doing. First try at posting photos. Since it seems Corona Covid-19 will go on for a while, therefore this a good diversion to focus on construction, not depression.

Start of Stearman PT-17 Build.JPG

[heywooood]

Don't over think it - the notches don't need to be perfect..only sufficient.
I would never attempt to use a belt sander on balsa model part sheets whether the are die crushed or not.
Use a sanding block instead and use 180 grit with minimal downward pressure. Just lightly sand the backs of the sheets and then cut them free with your exacto knife. Then using the plan illustrations of each former or wing rib place the part over the drawing to cut the stringer notches. You should also use a block to sand the edges of each part carefully to remove the fuzz etc

[MikeCallender]

Heywood,
Good advice, thank you. I am progressing slowly. 45 hours (according to the Guillow's web site) may not be enough. I am going slow and always going over the instructions. I will attach the landing struts and the stringers next. I am concerned about the "L" parts as with my other model I installed them backwards

Michael

[heywooood]

no worries, Michael - you've a good clean build started here based on the photo's you have posted. Nice Work.

If you want to look at a few built up examples of this kit you can look at the link below - Virtual Aerodrome (I've linked my build)
http://www.virtualaerodrome.com/image_b ... er_id=1322
And you can see all of the Stearman PT-17 builds by looking to the left of that screen and selecting 'View by Aircraft' and selecting 'View All' from that list.
there are a lot of them to view and all of them are inspiring

[MikeCallender]

heywooood,
You are in a different league then me. My goal is to make this one fly using a simple rubber band. I am not into the decals or the paint, although that might come later. If I can get the airworthiness right, I will be satisfied. Any pictures of the earlier build?

Michael

[heywooood]

Yes - I get that. Building for flight diverges from what I do only after the frame structures (wings, fuselage, tail etc) are built. To see more of that wrt to my Stearman just scroll through all of the pages in the link I provided. Pages 1-4 I think are where the bones of my build are found. As to the other builders and examples at VA, some build for flight (rubberband or electric RC as well as for display. The Guillow Stearman is actually meant to be a display model and therefore incorporates a rather heavy structure compared to kits designed specifically for flight. You might look at the Herr Engineering or Dumas Stearman kits if you want to build a flying rubberband powered PT-17

[MikeCallender]

I built the upper wing and the lower wing, although I still need to put on the stringers on the lower wing. Not easy and this has been a tough build for me. The challenge is harder with the work I need to do, it is hard to be motivated after I come home from work (or get done with a long day teleworking). I hope to get more down tomorrow. I am using a quick settling "crazy glue", but it is Polish and I am not sure I am doing it right. My goal is to build a flyable airplane, but who knows. The fun is trying to make it work. After I get down with the wings, I will finish the rudder and stabiliser in orde to complete the frame of the model. I have not decided if I want to detach the ailerons, but they are in place. While I love the model, not easy to do.

[MikeCallender]

Well, got to a point where I want to stop. This was a very complicated build for me, even though I steered clear of the plastic molds. I found the instructions were assumed too much for a new modeler. Some parts such as B5, needed to be sanded in order to attach the lower wing. I also had problems with the vinyl pieces, they were not labelled. It took me a while to figure out which ones to use and how to put them together. Additionally, support the nose cone with additional spars for support was a bit a challenge, the size depended on how much I sanded the nose cone and the depth of the support spars behind piece B1. Once I found a solution and after assembly, I tried to balance the plane. I am about 30 grams to heavy in the tail section. Of course, that is not exact, but a few test glides proved the model would go into a nose stall also immediately.
Regardless, nice hobby and I am excited about trying another model, but this time NOT an 800 series. I have one more 200 series I will attempt. Thank you to Don, KT, and Heywoood for the hints.

Michael

[Arlo DiPasquale]

Awesome first build! Starting with an 800 Series model was certainly ambitious, and I'm sure you'll now find other models a bit less daunting. If you build one of the 200 series kits next, feel free to message me with any questions, I've built almost all of them, and might be able to answer any questions you may have. You'll love working with the laser cut parts!

[VUCA]

Your Stearman is looking good, Mike. Congratulations. I just bought the same kit, and am having some trouble understanding the stacking of parts to build the leading edge of the upper wing and how they merge to the wing tips.

It appears the leading edge itself is stacked on small blocks of balsa, but the tips are flat against the board. Also unclear as to how the front of the ribs align to a leading edge that is up off the plan.

How are those pieces supposed to be joined?

[MikeCallender]

VUCA,
Thank you, yes that part had me stymied for a while. If you look at the "building instruction" Step2, at the top left and just under the Botton Wing, there is a small diagram of the a side view of the rib and the leading edge. Para 3 in the written instructions gives a little more evidence of what you should do, but this too is not very clear.
Once I had the outline of the wings completed (the "G" parts) and dried, I removed the pins and raised it with an extra stringer as depicted in the "Bottom Wing" section of the instructions. I never could picture what this looked like until I was finished and started sanding the leading edge.
When I glued the spars to the leading edge, I would align the spars with the top of the leading edge (same as the small diagram). It took time to hold the spar in place while the glue dried (it was fast drying so not that bad). It seemed to work, but it never really made sense to me. My guess is that this engineers an "angle of attack" into the wing. This is also what made me skip the dihedral int he lower wing and making the flaps. What is your approach?

Michael