Goldberg Utimate Bipe Kit--changes?

I've been out of the hobby for about 10 years. I bought one of these kits about as long ago. I got as far as the tail feathers, then at one point the box fell into a basement junk heap, scattering parts. I'm not sure what is missing.

So I'm thinking of buying a new kit. The question is what changes have taken place over the years? I understand they now laser cut instead of die cut, so I assume the kit is of higher quality due to that. Any changes to the landing gear structure, notorious for being poor, etc.?

Engines: I'd always thought I'd install the largest 2 stroke I can fit--something in the 1.0 class; but I see, for example that Saito has a new 1.20 4 stroke gasoline engine. Maybe a 60 2-stroke is adequate, but I've always insisted on over-powering my planes.

Finally, it's been a long time since I've flown. I'm guessing I shouldn't try the maiden flight solo. Probably should get a little trainer time in. Any other experiences flying again after a long lay-off? I also logged about 100 hrs full scale time in the mean time and wonder how that will effect my RC flying. Dave

Reply to
DaveH
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On Mon, 26 Mar 2007 11:51:14 -0500, DaveH wrote in :

I haven't heard anything about changes.

You may have to be our guinea pig and let us know what you find out.

Saito 1.80?

Some things to think about:

When the plane is coming toward you, push the aileron stick to the side of the low wing to level out.

If you get into trouble upside down, help is just a half-roll away.

Don't be a hero. If you are afraid you have started a figure 9, do not complete the maneuver. Push, half-roll, pull and you've got the first half of a Cuban 8 to admire rather than repairs to do.

Spin recovery: first line of defense is to let go and wait, wait, wait. If it comes out, don't honk too hard on the up elevator too soon. You might just restart the spin.

Bipes are draggy. If you lose power, do NOT try to extend the glide. "Dead stick, stick down." Push the nose down a little bit to keep up airspeed.

Maybe try to get some time on a flight simulator? They're fantastic for limbering up your fingers.

You'll have to tell us that after you get back from your first day at the field. I've found a few full-scale pilots a little hard to teach, but you flew RC before full-scale, so it may not make any difference to you.

Marty

Reply to
Martin X. Moleski, SJ

.....snip

Thanks for all the suggestions Marty. Bipes are draggy and that's something I may have forgotten.

I was actually thinking of this engine, not Saito:

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20cc/1.20. Which engine is always the perennial question.

Flight sims. I'm sure a search will yield some answers, but the only sim I've tried years ago was MS's full scale app--"FlightSim"?. I think I've read that there are sims available that allow for interfacing an R/C transmitter with a PC. That would be excellent if the physics aren't too bad.

Also, I've got figure to out if my old Airtronics stuff is still useable. I know a narrow band restriction was implemented at some point--forget when and the details. I've forgotten a lot!

Oh yes--Interesting about full scale flying. I found that there definitely was some carry-over from R/C to full scale, and eventually concluded that there would be much less carry-over from full scale to R/C, as is frequently seen, consistent with your observation. Regards, Dave

Reply to
DaveH

I have that eng.(zen 20) on a 60 size bipe(GP Super Skybolt). It's a heavy engine but the slybolt needed it to balance. The Ultimate shouldn't and it's not got the power to weight you will expect if you like to over power planes. It is a neat engine. My first gasser. I also have the ultimate in a kit. I have an MVVS 90 and an Evolution 1.0 that could go on it. A 120 or 125 4 stroke would be really cool. Golly, you just can't beat a good

2cycle for power to weight without all those moving parts to deal with on a 4 stroke. Well, you've prompted me to go to the shop and clean and ponder building that Ultimate kit, but then I do NEED a fun fly plane, maybe a bashed Uproar with trike gear(got 40 and 60 kits), or I do have one of Paul McIntosh's Ballisticks I could get to.............. BBL mk
Reply to
MJKolodziej

I flew on on a Saito 1.20 4 stroke alcohol/nitro engine at sea level and it was great. Not quite unlimited vertical, but close. I moved to about

1500 feet elevation and a hotter climate and it was a little light. I put a Saito 1.50 4 stroke alcohol burner on it and it was a rocket.

They are REALLY nice flying planes.

Regards, Bob

Reply to
BobH

On Mon, 26 Mar 2007 18:03:28 -0500, DaveH wrote in :

Yep.

It'd probably be lots of fun. A couple of guys in my club fly them with YS 1.20s. It's a nice match. I'm planning to try a YS .91 AC some day in a used CG Ultimate. I need the courage of my convictions to mate the engine to the airframe and go learn how to run it.

The physics keep getting better. Even bad physics lets you practice hand-eye coordination. You can wring the planes out and not worry about the cost of the crashes. If you have a club nearby, I'll bet that someone has a sim and would let you use it for an hour or so.

If you flew after 1991, you're probably OK. Look for the "gold sticker." Get new batteries, do a range test, have fun!

Marty

Reply to
Martin X. Moleski, SJ

ROFLOL!

I am glad to see that *I* am not the only crazy around here! Mine started out with a Saito 120 and I ran it until it carboned up so badly we did a tear down at a fly in 200 miles away just to clean it up enough to have fun. I replaced the 120 with the 150 when they cam out and was IMPRESSED!

Three changes I made to my aircraft may or may not interest you. The wingspan is only 54 IIRC, but I stretched my to 60 (IMAA legal ) and built the tail feathers outside the plans to help compensate. I also shortened the nose 1 inch to make up for the heaver engine. After the lower spars got broken by the wheelpants, I took them off [:(] When I finally got tired of fixing the lower wing, I put Halco gear on it.

I miss that aircraft and just might break out the Ohio RC kit (64"?) and hang a 3.7 gasser on it.

Jim Branaum AMA 1428

Reply to
Six_O'Clock_High

"DaveH" wrote

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The Zenoah 20cc engine will be fine.

I can't remember if you are building the kit or buying the ARF, so I'll yak anyway.

The kit of the CGM Ultimate Bipe was designed for a .60. But even with only a .60 in the model, which hardly anyone ever used, you would do well not to duplicate the wimpy elevator and rudder linkages. They show the designer using soft S-bend in the linkage where the pushrods exit the fuselage. This is bad engineering and will lose you an airplane, assuming that you have enough control after flexing to control the model at all. It's one of the few goof-ups I've seen by CGM, who used to design and kit some really good model airplanes.

I'm not familiar with the ARF version, but there is one sitting in the garage awaiting unpacking, so I'll know soon enough.

Ed Cregger

Reply to
Ed Cregger

It's a kit Ed. I'm a mod nut and inadequate linkage/servo issues I always address is necessary. Thanks for the heads-up. Dave

Reply to
DaveH

MK, I'm building an Uproar 60 right now. Tail feathers and one wing is done, no covering yet. What changes would you (or anyone else) recommend?

I had a miserable time with the sheeting on the top leading edge of the first wing. Must be old balsa. Guess I'm going to have to wet the sheet to keep it from cracking. . I've never done that before. I understand vinegar and water is the normal wetting agent. What is the mixture? This is my first build in 47 years, and all things considered its going well. I'm learning that I don't like thin CA, I'm impatient with Titebond II, and I'm experimenting with a combination of the two.

Harlan

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Reply to
H Davis

On Tue, 27 Mar 2007 14:47:14 -0500, "H Davis" wrote in :

I think the old recommendaton was ammonia and water. Googling a bit, I see:

  1. Folks disagree that adding ammonia is any help. They recommend a long soak instead (4 hours for 1/16" balsa sheets).
  2. Some folks say add a drop or two to the water. They don't say how much water is being used.
  3. Industrial processes use anhydrous ammonia (free from water). The gas is poisonous and the material has to be sealed in a container with the gas. Not something that's of any use to us hobbyists at home.
  4. Steam the wood to make it a little more pliable.

Here's the google search:

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Let us know what works best for you!

Marty

Reply to
Martin X. Moleski, SJ

Harlan,

Ammonia is your friend!

I keep a quart at the building bench.... less than a buck to buy. I dab it on liberally with a piece of sponge. After that, you can have your way with the balsa sheeting. :-) (CA will stick to balsa still wet with it.)

Good flying, desmobob

Reply to
Robert Scott

I've just read the man. today and have been surfing the web for mods and tips. I'm considering taller gear in trike setup.(one fun fly has lots of taxiing events) I'm thinking about not tapering the Ail. at the root. The Ail. is prob wide enough but it might be good to have more in the prop wash. I have a canopy that would make it look a bit less "Towerish".

I'm going to wet the LE sheeting. Just water would work, or a bit of vinegar, or ammonia, or alcohol, I feel like it dries faster.(shrug) Med. CA gives you more time, or thick CA. I have some Ambroid to assemble the sides with, maybe other parts. I'm willing to hear about advice and mods. If I put that Evolution 1.00 NX on front, will I need to shorten the nose to Bal.? Maybe you or I should start a new thread Harlan. mk

Reply to
MJKolodziej

"H Davis" wrote in news:05GdnVi4PaZT6ZTbnZ2dnUVZ snipped-for-privacy@wideopenwest.com:

First & foremost - don't rule out buying a few sheets of balsa! If your LHS has some nice A-grain, it'll make your life a lot easier.

But barring that, I prefer alcohol (rubbing alcohol) over ammonia, partly because the smell is so much less irritating to me. Rubbing alcohol also seems to evaporate faster.

Just my $0.02, and probably not a bargain at that.

Reply to
Mark Miller

Yeah, mk, I guess I need a little lesson in etiquette. I think I did what is called "high-jacking a thread". I wouldn't appreciate it if it happened to me, so I will apologize to the original poster.

I'll start another thread on mods to the Uproar.

Harlan

Reply to
H Davis

Balsa covering problems are interesting. No problem here. Dave - OP

Reply to
DaveH

If the wood won't bend to a simple airfoil shape using just water, get some good balsa from Lonestar, Sig, or Balsa USA. I have never had the need for ammonia -- it stinks! However, for your wing sheeting, try just wetting ONE SIDE of your sheet -- the outside. Use a wet sponge; let it soak for a few minutes, then wipe off with a paper towel. The sheeting should be nice and curved and almost a match for the airfoil.

Cheers -- \_________Lyman Slack________/ \_______Flying Gators R/C___/ \_____AMA 6430 LM____ / \___Gainesville FL_____/ Visit my Web Site at

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">> I had a miserable time with the sheeting on the top leading edge of

Reply to
Lyman Slack

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