Scale Build-Off- ParkflyerPlastics 95" span P-40
- Thread starter wilmracer
- Start date
Glass repairs continue. In this part the paint is sanded off down to the glass and the seam and any dents are filled with epoxy/micro-balloon slurry. These areas will be sanded smooth again, then roughed up and a layer of .75oz cloth will be laid down. Once trimmed that will be blended in and primer will be put down. I'll have to redo the panel lines and rivets in these areas but it will be easy to do.
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Kicking butt!
Thanks!
And thanks to Tench745 for that Keith Sparks quote. I needed something to write about for our club newsletter this month and that quote will do nicely
There's an idea... or put a few of those comical bandaids on it
If done right the repairs should be almost invisible.
There's an idea... or put a few of those comical bandaids on it
If done right the repairs should be almost invisible.
true. All depends on how you feel I guess.
One other little change that I'm working on... The original battery was 4 5s5000 mAh packs to make a 10s 10,000. This setup weighed in at 5lbs 12oz, plus the weight of the extra sets of heavy Y harnesses and the big battery tray. I like the idea of 10,000 mAh in the tank, but it is a bit overkill and it would be nice to save a bit of weight. So since I have to rebuild the battery box and I've already repurposed those packs for the Sbach I decided to pick up 2 5s 8000 mAh 30C packs. This setup weighs in at 4lbs 0.5oz and will also save a few oz by requiring only 1 "Y" harness. I'll be able to use a smaller battery tray as well. All told I'm hoping this will shave just shy of 2lbs off the AUW (assuming I can get everything to balance).
I was hoping to get some work done tonight but after problems in the office I just spent 13 hours at work and I'm calling it a night.
I was hoping to get some work done tonight but after problems in the office I just spent 13 hours at work and I'm calling it a night.
I'm super glad you put this plane back on the front burner, and look forward to a proper maiden flight (with some actual time in the air this time!).
Repairs continue, but I wanted to try something this evening. I ran to the hardware store for a pulley, some rope, and a plumb bob and put together a vanessa rig for balancing aircraft. I've never used one before but have seen others use them with success, and it seems to be a very convenient way to accurately find the CG for a model this size. I wanted this rig setup before I did any more work so I could determine placement for the new battery restraints and figure out how the "diet" was going. Another plus is that this will make weighing this (and other) aircraft a lot easier.
I also went back and read through some comments on the RC group thread for Spark's original build. He commented after my crash video that although he had been able to manage the torque effects he thought the design would benefit from a bit more right thrust. I'll add another degree or two before taxi testing, which I hope to get to in the next week or two. Of course the baby is due any day now, so... I guess we'll see
I also went back and read through some comments on the RC group thread for Spark's original build. He commented after my crash video that although he had been able to manage the torque effects he thought the design would benefit from a bit more right thrust. I'll add another degree or two before taxi testing, which I hope to get to in the next week or two. Of course the baby is due any day now, so... I guess we'll see
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That's a really neat rig! Haven't seen one of those before. I found a bit of a write up on how to use it over here http://www.rcuniverse.com/forum/tips-techniques-180/708060-vanessa-c-g-rig-how.html - think I'll be putting one together too.
I read through that thread before putting this together and basically copied that design. So far so good. I ended up using a lag bolt into a stud in the ceiling to hang the pulley from, and technically it shouldn't be used for lifting the way I'm doing it, but the bolt is rated for over 300lbs and I doubt I'd ever hang more than 25-30 from it, so I think I'll be fine
TexMechsRobot
Posted a thousand or more times
I read through that thread before putting this together and basically copied that design. So far so good. I ended up using a lag bolt into a stud in the ceiling to hang the pulley from, and technically it shouldn't be used for lifting the way I'm doing it, but the bolt is rated for over 300lbs and I doubt I'd ever hang more than 25-30 from it, so I think I'll be fine
I've seen these rigs and I just can't seem to figure out how they work from the images. Are there any diagrams or tutorials showing how to use the rig? I saw the one image in the thread you linked to that had the different wing orientations (low, high, bi) but it wasn't clear enough for me how the rig was balancing the CG.
I'm sure Carl can do a write-up for this but the idea is that the peg at the top can rotate to account for the weight of the airplane. The plum bob hangs down and points to where the current CG is. As you adjust the weight of the airplane the peg will rotate until your CG is pretty much dead on.
Its more complicated but in a nutshell, yeah.
Its more complicated but in a nutshell, yeah.
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TexMechsRobot
Posted a thousand or more times
That's actually more than I had pieced together lol. And that helps a lot. Maybe if I put one together the mechanics will make more sense
I have a 5 pound plane to balance and I wasn't sure how I was going to do it. I could probably use pegs but I'm just not sure.
I have a 5 pound plane to balance and I wasn't sure how I was going to do it. I could probably use pegs but I'm just not sure.
From the little bit I've done with it, it tends to work better on the bigger/heavier planes since it keeps the string tight. You'd want to be careful to protect the wings from the string cutting into them.
TexMechsRobot
Posted a thousand or more times
Thanks! Sorry to hijack the thread lol. Back to regularly scheduled programming?
So it has been a busy few weeks around here. Two weeks ago my wife and I had our first baby, Lily. She has been a lot of fun and has been keeping me out of the shop almost entirely. Last weekend my wife wanted us to do one of those newborn photoshoot things. I agreed but I had one condition... One shot had to be aviation themed. I think it worked out
As for work on the repairs... I built a new battery tray to accommodate the 5s 8000 mAh packs. Between the smaller packs and the lighter tray this is over a 2lb weight savings. With the other tweaks I'm hoping she is right at 20lbs AUW. I started tweaking the final location for the battery tray last night so as to properly balance with minimal extra weight. If I have to add an ounce to the tail I can live with that, but I REALLY want to keep the weight off.
Our new flying site is STILL not yet open, but I did get some great news about our existing site (Rockyboy... I don't think this has been shared with the club yet). The county is planning some additional cutting and burning around our field. The right approach has always been a little hairy because of a tree line about 200' or so before the approach. ALL of the trees on that end of the approach are to be removed and that area leveled. We don't know yet if we'll be allowed to extend the runway at all, but at the very least that approach will be MUCH more friendly for big stuff. It sounds like that won't start until early next month, but long term it does sound like our existing site will be friendly to the P-40.
As for work on the repairs... I built a new battery tray to accommodate the 5s 8000 mAh packs. Between the smaller packs and the lighter tray this is over a 2lb weight savings. With the other tweaks I'm hoping she is right at 20lbs AUW. I started tweaking the final location for the battery tray last night so as to properly balance with minimal extra weight. If I have to add an ounce to the tail I can live with that, but I REALLY want to keep the weight off.
Our new flying site is STILL not yet open, but I did get some great news about our existing site (Rockyboy... I don't think this has been shared with the club yet). The county is planning some additional cutting and burning around our field. The right approach has always been a little hairy because of a tree line about 200' or so before the approach. ALL of the trees on that end of the approach are to be removed and that area leveled. We don't know yet if we'll be allowed to extend the runway at all, but at the very least that approach will be MUCH more friendly for big stuff. It sounds like that won't start until early next month, but long term it does sound like our existing site will be friendly to the P-40.
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