Hey Folks:

With the Dora all done, it looks like I will have to get crackin on my silver plane for next year, a World Models Hawker Tempest. With that coupon for 1/2 off on that motor, it looks like I will be putting a 115 instead of a 110. It Should make things interesting. Rather than typing I just did a video segment with questions about the build. So any help from the racing crowd is greatly appreciated. So here we go....

http://www.youtube.com/watch?v=IpmHmwp7QxY

Hi Jake!

Congrats on finishingthe Dora; I'm looking forward to seeing her fly.

I'm hearing some reports in the forum threads that the YS 115 vibrates the airframe heavily. I think you'll needadditional reinforcement. Beings you are already planning on putting thinned epoxy inside anyway, why not put some 3.5 - 4 oz. fiberglass cloth in that area while you're at it? The addition of cloth will add significant strength, but next to nothing as far asany additional weight.

For Silver, some will tell you thatyou could probably get away without fiberglassing the center section of the wing. But personally, I wouldn't risk it. I recommend fiberglassing the centersection anyway, and never having to worry about<u>IF</u> it will hold. It is cheap insurance and makes for one less thing going through your mind come race day. Furthermore, you not only have to worry about whether it will hold in the near future, but more importantly . . . will it hold without the reinforcement after those less than perfect landings, season after season?

(I just got done fixing the wing on the purple and yellow Mustang before the last race,because I had noticed the wing was flexing more than it used to. I found thatseveral ofthe glue bonds between the sheeting and ribs had weakened and were beginning to fail from all the repeated stresses of multiple hard landings, flip-overs at the end of the runway, vibration, etc., over the last 4 years and 2 fuses it was attached to. Many racers don't reinforce, and then don't notice the minor fractures that weaken the joint until it's too late as they're going through the remnants in their crash buckets. I say, FGthe center once and be done with it.)

I would soft mount the 115.
I just installed mine in a new stiletto. When I grabbed the needle to start the breaking in, I couldnt believe the shaking. I could hardly hold onto the needle wire extension. In fact it ended up cutting my finger. Soft mount is a must for longevity- period.
I saw one of these hawkers fly at Speedworld with a YS140 and it was Gold Fast.
Should be a good set up for Silver with that 115.

Good advice folks, thanks.

Ollie: With FB the center section are you talking both top and bottom? What is the simplist process for this? Do I cut off the covering off at the glue joint and reapply new covering on the bottom or what?

MFlood: I am a little unfamiliar with the sof mounts, which one would you suggest?

Without a doubt the hyde mount along with the nose ring. The nose ring is what makes it work. With out it the motor mounts have broken even with alumn mounts. These lil power houses make some shake for certain. I just cant imagine what the fuse and wing joints in a basic arf would be like after a few races with this engine. It reminds me of my Harley with a 96" stroked shovel head in a small FX frame. It shoke everything loose.

If you are going to invest in that WM plane and that awesome YS engine spend the extra and ensure the life of the set up as well as the humans in that area. Get a soft mount with a nose ring (not just the mount).

On another note:
I just tached my new 115 with a 14x14 N on the ground (first run up) on heli (30%), and it hit 8900 with a good setting at 8500-8600. I cant wait to get this broke in and then turn up the nitro, it should hit 9500. I have switched to a 14x13N for now to keep the RPM's up so my cylinder walls will accpet the higher RPMS once it is broke in.

I hope to come up there for a race in the near future, as it sounds like you Sac guys really love racing like I do. Plus I can put faces to all these names.

Why not wait for the new YS125 where the shaking has been eliminated and bhp has been increased beyond a reworked YS 120SC?

Well the best reason would be cause they aint out, and the 115's are, and we be watin to race.

That 115 is a monster and pretty small.
As of now it is the engine to have, not that the 120's are anything less, just heavier.

I built a Tempest with a 140 in it. It really hauled the mail. The wing really turns. You are going to like it. I got it a little low trying to catch Marty at the Utah race and plowed it into a hillside. I did have a problem getting the plane to roll. It tended to nose over on the ground. I had to hold full up on take off or it would rotate forward and strike the prop. Just something to watch for.

Blessings, Terry

I fiberglass both top and bottom. This ishow I do it:

I measure out about 2 1/2" from each side of the center joint, and use a straight edge to cut away the covering. (Obviously you need to be very careful/delicate and cut through the covering, without cutting into the wood. Otherwise, you'll weaken the area just outside the area ofreinforcement work you are about to complete.)

Rather than just using one layer of heavyweight FG cloth, I use two pieces of slightly lighter weight 3" fiberglass tape. Or you can use standardcloth, cut into 3" strips. Each has its advantages and disadvantages. The tape is already cut and its edges won't unravel on you; but the woven edges of the tape tend to be thicker, can sometimestend to curl up slightly,and due to both of these factors leave a moreobvious raised line. The cloth takes an extra step to cut, and can unravel on you; but you may already have it on hand, and the edges tend to lay flatter and seem to sand out a little smoother with a little less work.

I lay one piece primarily on the left wing panel so that 2" are two the left of the wing center joint, and the remaining 1" overlaps this joint, extending about 1" onto the right wing panel. Then I lay out the piece on the right panel similarly, but with oppositeparameters. (See the primitive drawing I made for you, below.) When completed, this arrangement gives two overlapping layers where it is needed most . . . at the very center; and 1 layer extends another inch to each side where there is still significant pressure being applied by the G forces in the turns. This arrangement also makes sanding it relatively smooth much easier than just one extremely thick piece that more abruptly announces where the reinforcement ends, and therfore would make recovering this section more difficult, and far less attractive.

After curing, give a quick rough sand to remove high spots and those potentially flesh-piercing FG "needles". Fill with balsa filler, and sand relatively smooth, but don't get counterproductive by cuttingintomuch of the cloth. Sand it just well enough to get the covering to lay over it reasonably well when you re-cover this section. (Don't worry: the top is hidden by the fuse, and most people don't get a close or prolongedlook at the bottom.)

Recover with compatible piece(s) of iron-on covering (overlapping as is usual), and you are done.

Hope this helps.

Thanks Ollie! Very descript and being the visual learner that I am, the diagram is very helpful. What about the factory installed hinges? Should I worry about them or are they good to go?

Man, those soft mounts with the ring are expensive!!! I don't know if I am looking at the right ones but they are pushing 200 clams. I had no idea that the 115 were known for bad vibration. Should I just stay with the 110 route?

From what I have seen the 140 is a great match for that plane. I dont know if there was any added weight or if it balanced perfectly. But they do move out. I am sure a 120 would be a good engine as well.

Yes $200 is on spot for that soft mount. Maybe look at a Hayes soft mount but be sure to get a nose ring.

I just think a 110 would be "Ok" for silver, but may force you to have stick it on the poles everytime and leave no room for error.

I asked Richard Verano about the reports of excessive vibration in the 1.15 and he said it is not true. He did say that with more power, you will get more stress on the airframe. Richard runs a Hyde mount with the nose ring but he says it is so he can build his plane lighter.

The Tempest looks draggy but it didn't seem to be in the air. I bet a 1.10 would be fine for Silver. The Tempest comes out very light for it's size. That big cowl looks draggy but it is wide open in the back so I don't think that was an issue either. I would recommend not hooking up the flaps. I did, and I think that gave me a lot of grief the last time I flew it. I had the plane all dialed in for a full pull on the elevator. I had flown it at least 50 flights without a problem. Then I get to Utah and the first heat against Marty, it is snapping in the turns. Freaked me out. After that heat I dialed out a bunch of elevator in hopes of fixing it. Then just before the next heat I noticed that I had inadvertently bumped the flap switch and the flaps had dropped to the mid setting and I hadn't noticed it until then. I'm sure that is what caused the tendency to snap but it was too late to change the elevator setting back because the countdown was already started. Trying to horse the plane around the pylons with too little elevator was a contributing factor in my dumb-thumbing the plane into the hillside.

As for the hinges, I didn't do anything extra to mine and they held up just fine. I would strengthen the firewall. Mine held but it just looks like a place that could use some attention. If I build another one I will glass the box before installing the mount.

I sure loved the way it flew. Especially the way it would crank around the pylons. Yee-haw!!

The point is well made there Terry. The YS115 doesnt have "Excessive" vibration, but it certainly has more than the 110. But it is a 4 stroker, pumped up with 60% and its gonna make some power. And that is one big piston pony pokin power makin piece of perfection.



Terrys hawker was fast, but we were no where near Gold speeds, especially for those of you to the north with new break out times. Of course if he had that thing turning like he wanted, it wouldve easily wiped 10 seconds off his time and pushed me to run tighter bringing all of our times down. I dont think I even broke into the 30's that day.

Wow, Marty . . . that was an altogether acute alliterative articulation aimed at your audience about its arrow-like agility in action! Impressive, sir. Those YS enginesare poetry in action, though, aren't they!?

exactly sir!!

Hey Marty,

You're right about our times that day but that is a tough course to turn fast times on. With all the hills and valleys you are flying over the air is a bit dirty and the pylons are hard to judge with all the beautiful countryside behind them. I know I didn't push you much. You can easily lose a second recovering from a plane that snapped out of a turn. Just screws up your whole game plan. The course only affects the times though since everyone is dealing with the same things. The racing is still fierce and every bit as fun.

I only wish I could have pushed you a little more so we could see what that Stiletto could turn. Are you planning to go to Prescott in August?

Blessings, Terry

Terry,

I will miss that race. I will be Giant Scale Racing in Kansas that same weekend.

I took that stock 110 out of that plane from SG, and put my slightly modified 110 in it, which is good for another 300-500 rpms.

In fact I liked this plane so much I went ahead and got another one and stuck a 115 in it. I just copied my other model over and went out today and maidened it and it is a rocket. I still have it fat at 3 1/2 and 30% heli and a 14x13N.

It sure flies great.
I will be ready for one of these upcoming races. I am quite certain either plane can break out, especially with a good caller.
Looking forward to racing with all of you guys when we meet up again.

Jake
I'd run some more thin CA in them and put a strip of clear monacote across all of the hinge joins underneath sealing up the air flow through the gaps and and call it good. (plus it adds strenght)

Oh I forgot, I'd use a Dave Brown 90 Glass mount it gives some flex. That would be fine for silver.

Jake, now you know why I stay the 2 stroke route. I think that if I take off the engine and electronics, it costs me less then that to build my whole airframe! LOL. Will be looking forward to doing battle with you in silver. Now if I could just figure out how to compete with the break out time and not other pilots.

I can't give much advice on the longevity of the WM hinges, as I've only used their wood fuses, and make all my own wings and tail surfaces; and therefore do all the hinging myself.ButI've seen the "grey dust" from their metal hinges, and always been worried about whether the wear would cause enough slopfor there to bean issue with flutter. I call for Casey, and harass him constantly about this dust all over his control surfaces. It's all in fun, but these surfaces DO concern me with how much play they have,yet he's never had an issue. I remember seing a thread about thisissue quite awhile back. Read it and see what you think:
http://www.rcuniverse.com/forum/m_9123809/tm.htm

If you do replace the hinges, I personally have have better luck with Robart hinge points and the heavier duty pinned hinges, over the long haul . . . compared to CA hinges. If fact, Sullivan just had one of his aileronsfail at the last race. He said it caused a snap and that's what caused his "Panama Jack" P-47 to go in at the last race. He told me he's never using CA hinges again. The Robarts and pinned hinges add another benefit: More free-moving, with no resistance to control inputs. CA hinges always seem to be pretty stiff and resist being flexed. I'm no expert, but common sensewould make me suspect this makes your servos work harder, and therefore causes additional draw on your battery.

Thanks for the thread Ollie. Good info on hinge wear and tear. If there is not a universal consensus on switching them out I think I will just leave them in and just keep a mindful eye on them.

Well, I removed the covering from the top and bottom of the wing and glued the sections together. Pretty smooth with no issues. I will be in Sac on Tuesday so I will go to R/C Country and grab a bunch of goodies that I need, including the fiberglass to reinforce the wing and and firewall. After working on the TF kit, going back to an ARF is so simple it's ridiculous. Here are a few pics of what I have done. There is also some pics of the stock wing screws. I am used to the larger nylon bolts. Do most pilots replace these screws with the nylon bolts or do they just use the stock ones? Just wondering what the standard is here.

Also what servos do you silver folks rec for the control surfaces?

Jake,

For what my opinion is worth, I prefer the 1/4-20 nylon screws, for afew reasons:

1. They are still plenty strong to hold up even at gold speeds, yet they will sometimes still snap off when the airframe makes those unauthorized contacts with the ground, andoccasionally save the airframe from quite as extensive damage (when you are really lucky).
2. Being a bigger diameter, there is more wood that would have to be "compressed" in order to enlarge the holes. This makes the area around the bolts slightly more resistant to eventually enlarging the holes through vibration, "hanger rash" dings, and tweaking the wings on bad landings and flipsat the end of the runway.
3. When I've cartwheeled planes with the smaller diameter metal bolts, the sheer just pulls them right through the wood and out the back at the trailing edge, making a repair to this area much more difficult, and weakening the structure so much that even when repairable, I find it hard to trust that it will hold over the long-haul. Similar to what I said in an earlier post, that isjust onemore thing going on inthe back of your mind, potentially worrying/distracting you when you want tohave fullconcentration on the competition.
4. When one falls out, and you can't find it, someone always has a 1/4-20 nylon bolt. Will they happen to have that <u>metric</u> size that comes standard with the kit?

Have you decided on a 115 or a 110S, yet?</p>