My Shoestring Stunter is RTF

Hmmm, maybe I misunderstood him then. Perhaps it comes that way. Or, maybe it was a popular mod. Who knows, when my kit arrives I will looks at the plans.

Ron, the cowl is non functional. The reasoning that Joe and others do that mod is that in Fox racing, you want quick restarts. The main problem with a Fox is that the case becomes quickly heat soaked once the engine quits. This is what separates a so-so Fox from a good Fox. The steel liner quickly expands away from the piston when hot allowing for little to no compression. When the plane comes in for a re start, I pour water or fuel all over the engine and quench it immediately and quickly fuel and fire it up. Out of 10 Fox .35's, you just may receive one that is superior to the others in terms of power and re starts.

The Fox has a very poor thermal exchange rate due to the eggshell thin case. Some Fox's are better than others for this and that is typically due to the fit of the liner into the sleeve. It's been said that a tighter fitting sleeve in the case can allow for better cooling due to the conduction of heat from the liner to the case. I find that once the engine is pushed hard with engines with tight liners, the engine doesn't allow for the thermal expansion of the liner quick enough therefore I lap the liner into the case allowing a looser fit. Ken

Could you apply thermal paste to the liner to give it better heat transfer? If it's like the few liners I've seen there should be no blow-by to wash it out. There are non-metallic compounds if glow plug contamination is a possibility. It takes only a sub-micron thin layer to work.

When filling gaps in balsa, what's your preferred sawdust for epoxy filler, balsa, pine, hardwood...?

micro balloons or if i just need to fill a low spot or crack repair after glued, DAP light weight spackle.

This is for structural integrity. I have gaps on the fuse on the Shoestring that need packing. Last night I only glued the sticks in one side and put it together to check the alignment. I want to seal the deal tonight and move on to the wing repair.

Use full strength epoxy on break, then after it sets fill low spots with spackle or spackle/epoxy mix or spot putty if needed.

Or you can use Aliphatic Resin Wood Glue, it’s probably not as strong as epoxy but for that repair (I’d spray a little water on the break first to help bond) and use wood glue, still stronger then balsa itself. Then fill low spots with wood glue/spackle mix or whatever.

Whenever I have a break like that, I use West Systems T-88. This particular epoxy has approx 1 hr open time and full set takes place in about 24 hours. This epoxy is slightly thicker than your hobby store brand but the strength is quite impressive. Hitting it with a heat gun once in place allows it to run into areas and really soak in. Something I noticed with the hobby store brand epoxy is that the faster setting epoxy tends to become very rubbery over the course of time while the slower set has a tendency to become hard and brittle. T-88 has a long open time which allows for good penetration. I've also had success on oil soaked areas. On larger gapped areas, I mix milled fiberglass into it which works as a structural binder. This epoxy while at first glance seems expensive, it makes up for it in performance and shelf life as it lasts a fairly long time. Like any epoxy, you shouldn't be having skin contact while using it. This stuff is no different and safety measures should seriously be used. Ken

I am rather liking this cotton flocking. It is strong, and fairly lightweight, stays put.

Phil

T88 is a System Three product.

I believe the G-flex is the comparable West System product.

I am currently using Locktite Professional which seems comparable, and available inland (otherwise I would have West System)

Phil

I was out there gluing while y'all were replying. Last night I had glued the bamboo dowels into the tail section and test fit it before taking those pictures. Tonight I practiced aligning everything, and then mixed some Loctite Pro 60 minute epoxy and filled the three dowel holes in the front end and covered all the surrounding wood on both sides with the plain glue. A few minutes later I stirred in a thick dose of pine 2x4 sawdust and covered it with that making sure all the ill fitting gaps were covered. I pressed it together and braced it with a straight edge and measured the distance from the TE to the hinge line, and got it exactly the same on both sides. The stab is perfectly parallel with the wing. It appears the fuse may have had a slight twist to it. It does not now. I babysat it for an hour making sure the glue stayed in the gaps, and must have checked the alignment 20 times.

I bolted my small vice to an old brake rotor so I could put it on the floor to hold the nose of the plane. That allowed me to stand and gaze over the stab and eyeball the wing. I feel pretty good about it. The Loctite has been my friend, though it is more brittle than 30 minute. But I'm glad I used 60 this time, because it was not a quick job. It's been polymerizing for an hour and fifty minutes now, I'll check it after I eat supper and watch Gold Rush.

Here are some more cell phone pictures for your viewing entertainment.

very nice! looks great!

I stopped watching the gold miners, but still watch (DVR) Ax Men and now Duck Dynasty!

Man Rusty, you don't do anything on a small scale. I used 5 min epoxy and 2 clamps today to fix the same problem.

Looks good. Can't wait.

cribbs74 wrote:Man Rusty, you don't do anything on a small scale....

Sure I do. I use 30 and 5 minute, though 30 is my most used. It was just difficult to work with something this size, my first time, anyway. So I needed the extra time to get it right. I usually don't bother with skewers on the small ones either. Now I patch the elevator, paint the repair, and cover the wing. My engine should get here Monday. Tracking shows it's been here in Columbia since Friday morning.

18mph winds are forecast for tomorrow.

I hit the jackpot on Shoestring pieces last night at the club meeting. The previous owner gave me a new fuse, maple bearers and doublers, new landing gear of the wide metal plate variety, and all of the tail feathers. I'm going to the HS today to get a piece of LE stock and spare wood. Meanwhile it might be ready to fly in its pre-rebuild, epoxy slathered form by this weekend... if I ever intercept my engine, which is aimlessly bouncing around somewhere in the US postal system. I'll cover the wing with whatever leftover Monokote I have, red or Navy blue left over from the Flite Streak.

I've got all the pieces cut out for the old T-28 too. I'm actually multitasking.

Score!

I should be done with my Ringmaster this week. If you get a chance to fly before me let me know how it goes. I am a little leery of all the extra pull and power.

cribbs74 wrote:Score!

I should be done with my Ringmaster this week. If you get a chance to fly before me let me know how it goes. I am a little leery of all the extra pull and power.

Meeeee too. I have the 60' wires and a Sullivan Insta-Just #2 handle. Not sure I like the feel in my hand, but I'll see how it does. And it has a lanyard. Don't forget that. When my friend lost the handle with no lanyard on the Shoestring, he said it was because when the wind slacked the lines, a line hit the grass and the plane came back tight and yanked it out of his hand. Sounds fishy to me at best, but still...

I better make a stooge for a rolling launch. If my engine comes, and I have the other things I mentioned done, Sunday will be the day, weather permitting, of course.

Even when I fly my old faithfuls, I'm always a bit nervous at first. It goes away as soon as I pick up the handle, but it's a slight nag up until then. When I get ready to fly this beast, I'll probably have a bit worse case of the uneasies. Do you ever get that? Someone here said they always approach the field with 100% confidence and calm. Not me though. I think that was SuperDave that made that claim. He probably does.

I bought three props today. Mark recommended a 9x4 or a 10x4. The book says a break-in with a 9x5 and fly with a 9x6. The LHS was prop challenged and I came away with a Master Airscrew GF 9x4, a wooden Top Flite 10x4, and an APC 9x6 scimitar. They didn't have any kind of 9x5. I was hoping for all MA props, but got what they had. They are all almost balanced, ut not quite. I'll treat the APC and MA like i always do, but I don't know about balancing a wooden prop.I suppose I have to re-seal anywhere I sand on it, but I don't know what to use. It's only slightly heavy on one blade, and it's very light, so I think I'll just leave it alone. I'll take input on that if anyone can guide me.

RknRusty wrote:

cribbs74 wrote:Score!

I should be done with my Ringmaster this week. If you get a chance to fly before me let me know how it goes. I am a little leery of all the extra pull and power.

Meeeee too. I have the 60' wires and a Sullivan Insta-Just #2 handle. Not sure I like the feel in my hand, but I'll see how it does. And it has a lanyard. Don't forget that. When my friend lost the handle with no lanyard on the Shoestring, he said it was because when the wind slacked the lines, a line hit the grass and the plane came back tight and yanked it out of his hand. Sounds fishy to me at best, but still...

I better make a stooge for a rolling launch. If my engine comes, and I have the other things I mentioned done, Sunday will be the day, weather permitting, of course.

Even when I fly my old faithfuls, I'm always a bit nervous at first. It goes away as soon as I pick up the handle, but it's a slight nag up until then. When I get ready to fly this beast, I'll probably have a bit worse case of the uneasies. Do you ever get that? Someone here said they always approach the field with 100% confidence and calm. Not me though. I think that was SuperDave that made that claim. He probably does.

I bought three props today. Mark recommended a 9x4 or a 10x4. The book says a break-in with a 9x5 and fly with a 9x6. The LHS was prop challenged and I came away with a Master Airscrew GF 9x4, a wooden Top Flite 10x4, and an APC 9x6 scimitar. They didn't have any kind of 9x5. I was hoping for all MA props, but got what they had. They are all almost balanced, ut not quite. I'll treat the APC and MA like i always do, but I don't know about balancing a wooden prop.I suppose I have to re-seal anywhere I sand on it, but I don't know what to use. It's only slightly heavy on one blade, and it's very light, so I think I'll just leave it alone. I'll take input on that if anyone can guide me.

I am always uneasy. At least until the first flight is under my belt. I wouldn't be surprised if the handle was pulled from his hand. I have seen guys lean way back while stunting. They have a good pull to them.

Thinned epoxy would work to balance without having to sand or seal.

[quote="cribbs74"]

RknRusty wrote:

cribbs74 wrote:I don't know about balancing a wooden prop.I suppose I have to re-seal anywhere I sand on it, but I don't know what to use. It's only slightly heavy on one blade, and it's very light, so I think I'll just leave it alone. I'll take input on that if anyone can guide me.

...Thinned epoxy would work to balance without having to sand or seal.

Good idea. And I think the wet weight is the same as the hardened weight, so it'll be easy to adjust as I paint it on.

an old trick for profile mount engines is, if the engine seems to vibrate more then normal, rotate the prop to the other side.

Mark Boesen wrote:an old trick for profile mount engines is, if the engine seems to vibrate more then normal, rotate the prop to the other side.

That's good to know. If it turns out to be a shaker like Ken discussed I'll try that.

RknRusty wrote:

cribbs74 wrote:Score!

I should be done with my Ringmaster this week. If you get a chance to fly before me let me know how it goes. I am a little leery of all the extra pull and power.

Meeeee too. I have the 60' wires and a Sullivan Insta-Just #2 handle. Not sure I like the feel in my hand, but I'll see how it does..

If you have the plane weight, estimated speed and line length, I can calculate the felt pull for you. Increasing the line length will reduce the felt weight on the handle.

andrew

andrew wrote:If you have the plane weight, estimated speed and line length, I can calculate the felt pull for you. Increasing the line length will reduce the felt weight on the handle.

andrew

Hey, Andrew. When I finish putting it back together I'll get the weight. Being my first non-half A, I have no idea about the speed though. It may be heavy as I'm only doing a repair for now. Later I'll completely rebuild it, as I have the fuse and most of the new parts cut out and will rebuild everything but the wing, which will be covered in modern Mono or Ultra.