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FT What Did You Do RC Today : Caution Offtopic At All Times

Do you have a link?
I don't remember if I have a build thread on it, I'll check. I know that I don't have any plans because I used the TLAR(that looks about right) method of design. It started out as an aleron elevator but the wing design was terrible so I built a new one and beefed up the boom with unidirectional carbon, hardwood and 1/32 plywood. Here are some picture of it.
Before mods
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After
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mrjdstewart

Legendary member
biggest issue with replacing firewall on xr-61 was making sure all was straight and when the new one was installed, the motor would be centered. i did some careful measurements and then made a template to transfer to plywood. pretty happy...

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it will sit farther back once i clean up the epoxy on the face of the old firewall. i will now hand fit to make sure all is good.

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we will win! :LOL:

laters,

me :cool:
 

mrjdstewart

Legendary member
so far so good...

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motor fits with firewall and all clearances are good. will pull back out and epoxy and fiberglass it all in. then clean up the center and motor bolt holes and we should be golden.

cross fingers,

me :cool:
 

mrjdstewart

Legendary member
Any holes going in to allow some air to get at it?
nope, don't think so. i am already worried that the ply is not thick enough to begin with, i don't want to weaken it anymore.

i just got the firewall epoxied into the motor box. cutting my fiberglass pieces now, then will mix up some more epoxy and go to town. the plan is 3 full layers, then strips running along each edge for added strength. well, that's the plan at least.

cross fingers,

me :cool:
 
Does anyone have any idea how to stop stray engines from following you home from swap meets?

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In my defense, it was 120 bucks, and came with a spare set of bearings and TWO spare mufflers/headers. It's also pretty low-time. The guy I bought it from said he broke it in and then flew it a couple times but ultimately decided it wasn't strong enough for the plane it was on.

I especially like that it's the later Surpass II variant, with the little tube that eliminates the breather nipple normally on the bottom of the case; instead the case oil goes back into the intake header and gets ejected overboard out the exhaust which gives you one less trail of schmoo to deal with at the end of the day. I think I'll add a T-fitting to this tube, so I can put after run into both the bearings and chamber.

Did I mention it also runs extremely damn good?


The high speed tach reading is obviously bogus. My tach sucks in direct sunlight and with dark colored props. Speaking of that, the MAS 14x6 on it is probably a little much in terms of load but I'd estimate it was getting right around 9k rpm running very much on the rich side, so maybe I'll just leave it. It was the only prop I had that wouldn't let it overrev while also not being way too much load.

It's also up there in terms of docility. I did not use the electric starter a single time. It just doesn't need it. One and seldom two strong back flips against compression was all it ever took to get it going. My Saito 91s are the only other motors I have that will do that with any degree of regularity.
 
Does anyone have any idea how to stop stray engines from following you home from swap meets?

View attachment 202025

In my defense, it was 120 bucks, and came with a spare set of bearings and TWO spare mufflers/headers. It's also pretty low-time. The guy I bought it from said he broke it in and then flew it a couple times but ultimately decided it wasn't strong enough for the plane it was on.

I especially like that it's the later Surpass II variant, with the little tube that eliminates the breather nipple normally on the bottom of the case; instead the case oil goes back into the intake header and gets ejected overboard out the exhaust which gives you one less trail of schmoo to deal with at the end of the day. I think I'll add a T-fitting to this tube, so I can put after run into both the bearings and chamber.

Did I mention it also runs extremely damn good?


The high speed tach reading is obviously bogus. My tach sucks in direct sunlight and with dark colored props. Speaking of that, the MAS 14x6 on it is probably a little much in terms of load but I'd estimate it was getting right around 9k rpm running very much on the rich side, so maybe I'll just leave it. It was the only prop I had that wouldn't let it overrev while also not being way too much load.

It's also up there in terms of docility. I did not use the electric starter a single time. It just doesn't need it. One and seldom two strong back flips against compression was all it ever took to get it going. My Saito 91s are the only other motors I have that will do that with any degree of regularity.
Ye I have an FS-70 Surpass and it's the same story. Put it on a 4-star 64 and it's an absolute dreamboat in flight. Yours runs just like mine!
 

FoamyDM

Building Fool-Flying Noob
I Have been busy

Friday
I went out and Tested an idea about what has been causing a Plane (The FB version of the Reptile, Dragon II) to behave strangely.
This Video Represents a typical Day of the field for me.


Usually started with a Failure, or some malfunction. Sometimes it's fixable. Then I get some fly time. The 1st go is to check on trims, bring it in, make adjustments. then to verify the adjustments are helpful, if so, fly and enjoy. Then if I am lucky... change the battery and fly some more.
BTW - if you rubber band your planes, be sure you have enough bands to keep the fuse tight. I went with too few, and notice pitchy-ness during the flight... the Fuse or wing shifted and would make the plane Tail heavy. (a shift of 1/4" was enough.) the extra rubber band did the trick. She now flies well. Now I have to figure out why 1 motor wants to hit100% at random spots during flight.

Just before the build-night Hosted by the Aviation RC Noob podcast I built the FliteTest Style build version of the wing. With that I filmed a build video.

Saturday
I took this back out with the Prandlt-D Modified Wing (see here) to test the spar reinforcements, and to fly with it. Along with the FoamBoard Reptile Dragon II @BATTLEAXE put together. As with my luck... As storm was rolling past a mile out. and the winds just started kicking up, 10 knots gusting to 23. Perfect time for a flight right? (most would have sense, and stay grounded.)

I decided it was time to see how they performed in the wind. Both did well.
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Note the wind sock

Prandlt-D - After trying to launch with a different (heavier) battery without success earlier in the week, I just put on what worked at the marks I had. It launched just fine, and I began flying. I caught a few thermals, but I noticed the pockets of Rising air were aggressive, and the Gusting would take the wing time and try to bat the plane around. The roll is slow and the coupled Yaw is on pace. This made battling the frequent violent upsets slow and a bit scary. There were many buffets that looked like the end of the Video above. but this time the wing stayed put. It was the violent motion that loosed a battery and caused it to become tailheavy and come down (guided). She will Fly again.

the Foam Board Reptile Dragon II @BATTLEAXE flew Great All around. now that the wing wasn't shifting around. on 3S it was gentle with some pick-up, and on 4S it was a ballistic missile. I hope to get the chance with the 5s.

Later I calculated out exactly where to place the LARGE 5Ah 3S battery for the Prandlt wing.

Started a Sub Nautica Submarine project - WTC ends, and bulkheads are printed along with fins, and the impeller. Perfectly.

Sunday - Fathers day and rainy. tried to figure out 3d printing failure... First big hull section. Looks like Under extruded from Skipping. Finished Black Sail (Starz) and I want to build a Man O' War Class RC Sailing Ship. :)
 
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A friend of mine found these three older foamies at a barn sale, no servos or batteries, but otherwise complete; $4 each.
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They run a 10x4.5 prop on a GWS brushed gearbox. Originally these would have run an 8cell NiMh battery (9.6v), but I'm running them on a 2s LiPo (7.4v). With that power combo the biplane just barely flies. I need to up the prop pitch to get a little more speed out of it
The planes came with some 72mhz mini recievers; wish they made a module for my Taranis to use them. Alas, I ordered some new FrSky Rx4R receivers instead.

I would love to identify the original plans for some of these planes. They all come in under 250g with a 480mah LiPo and should fly for about 12 minutes on that battery.

When my friend bought them all the seller threw in this guy: a Wattage Crazy Max. Apparently it was quite the performer in its day.
Same deal, no batteries, no servos, and this one had no ESC.
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