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Old Feb 16, 2008, 11:29 AM
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Holden , Massachusettes
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9 GRAMS....I'm not quite that bad...it is .9 grams. No that rubber was just for the picture. It's 3/16" and I've cut up some 1/16" and even a small 1/32" or so piece. But I'm not sure how to go about making a loop WITHOUT using a knot of some kind?

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Old Feb 16, 2008, 08:25 PM
B for Bruce
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The 'Wack, BC, Canada
Joined Oct 2002
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LOL No, no, the knot is fine. It's just that the picture looks like it has a knot in the motor already and a knot generally implies that it's done and ready to mount to the model....

Looking forward to reading about the flight testing. Actually I'm looking forward to reading your comments about the NEXT model that is about 1/2 or less the weight and the epiphany like unvieling of the Awareness it brings.....
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Old Feb 16, 2008, 09:10 PM
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Holden , Massachusettes
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BMatthews

Can't wait for that out of body experience. Actually have already felt what you're talking about, to some degree, in a 1/32" prop I made up (for next ezb). Have it hanging from a small wire above my bench and every now and then give it a spin, just to see it come to rest, almost perfectly balanced.

Well..to get on with the building:

Oh boy..fun time. Gonna try to add the wing mounts. Hard to believe the wing is going to be held on, by only 2 small sticks, of 1/16" balsa. Harder yet, that I'm the one who has to do make this happen. Well here goes.

Made the jig (mostly a drawing on the build board) as described in Ron's book. A straight, 18" or so, line, with a 3" line set at 90 deg. from midpoint of longer line.
LIned up and pinned down wing (onto TE) using small scraps of balsa (no did not pin through the wing LE or TE edges), on larger line. Made up the wing mounts using 1/16" sq. balsa and sanding till it resembled a round thoothpick. Had the paper tubes already made up, so used them to get just the right amount of roundness on the mounts. Flattened out about 1/16" at one end and glued to center of wing. Did the same with forward mount, except glued it to wing 1/16" off center. Am finding it hard to believe these mounts won't break off the first time I try to push em in the little round paper tubes. Well, I'll find out soon enough. Did some tappering on the forward and rear motor sticks (guess that's what you call em). Will glue the 2 together next.

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Old Feb 16, 2008, 09:45 PM
Free Flight rubber flyer
South Carolina
Joined Mar 2005
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Nice job, Eric. Oh how I wish competitive EZB's were as strong as that thing. I was flying a .6 g EZB in competition today...got a best flight of 8:29 under a 30' ceiling, but I'm here to tell you, that plane is not fun to work with, and with the prop spinning at sub-60 rpm, any imbalance in pitch (there's always some there) makes the model look like a sick duck in flight. End result, it's really nice how slow they fly, but they look pathetic while doing so. I guess I have to prefer 1.2 g EZB (F1L) as they are much smoother flying machines more akin to what you've got there.
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Old Feb 16, 2008, 10:49 PM
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Back in the day the wing posts were a push fit into some short tube sockets glued to the fuselage. It was normal to make the sockets out of jap tissue using a solvent glue like Ambroid or Sigment and roll the paper and glue around a 1/16 music wire mandrel. To make them I applied glue to the wire and then stuck that to the tissue. The tissue then being rolled around the wire so that the line of glue "surfed" along in the joint of the paper rolling onto the wire and paper already on the wire. About 3 turns was enough. Once the end was reached I'd roll it between my fingers to spread the glue around the outside and then as it got tacky I'd hold the tissue tube in my fingers and roll the wire inside the paper and pull it out while continuing to spin it. The wet glue on the inside being slippery enough to allow this. Usually the last little bit got pinched by my fingers. But since I'd usually make it about an inch long there was still lots of good "tubing" to allow making 3 socket tubes.

Once dry cut the tubes to length with a very fresh single edged razor blade. The advantage to using the paper and glue is that the glue is easy to remelt and makes for a very strong joint to the fuselage tube.

With these socket tubes you can then round the ends of the posts before glueing them on so that they are a snug but sliding fit in teh tubes. Once mounted to the wing the sliding fit allows you to alter the wing incedence at will as well as remove the wing for transport.
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Old Feb 16, 2008, 11:42 PM
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jwfinn

You just got to be kidding about a .6 gram ezb. That's less then my prop. While I do like the slow flight of these planes, personally, I too prefer watching a plane that doesn't fly like a propoise. Will be happy if I ever get a whole plane to weigh under 2 gram. Got a feeling this ones going to be up near 6 grams. Heck, YOU could make 10 planes with that much wood. Got to say it again .6 grams That's INCREDIBLE. You wouldn't have a photo of that plane would ya?

BMatthews

I used light weight writing paper as I had no Japanese tissue? I tried using the tissue I used to cover the wings with, but it just wouldn't glue up properly. I made em pretty much the way you describe, using elmers and rolling it up, sorta like making a cigarette (althought you may not be old enough to remember that). Only difference is, I used wood instead of metal to roll the tubes, around. The metal sounds a whole lot better, than using wood. Glued the first 2-3 tubes right to the wooden mandrel. Finally rubbed some candle wax on wood. Anywho got 2 reasonable long tubes, which I cut down to the right size.

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Old Feb 17, 2008, 09:12 AM
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Assembly

Made up a fuselage jig, to mount rear fuselage to front, and have it come out level, yet with the required, 1/2" offset. After that added rear motor hook, which was made by bending up some .015 wire and glued in with 5 min epoxy, used sparingly. Made up front bearing using some thin aluminum, and glued with same epoxy. Wound some kevlar tow, around rear hook and front bearing and glued with thin CA. After putting the now full fuselage back in jig added h. stab, with some tilt by propping up one side. Added lower fin making sure it was in the same plane as the fuselage (motor stick). Added prop and rubber band, then used string to find balance point. Mounted paper tubes according to Ron's book 7/8" to rear tube and 2 1/8" to front tube, from balance point. So it's pretty much done. Tossing it around the living room it seems to fly ok, nice and sloooow. So far have only the guts to give it about 50 turns or so. Will give it a real test Monday in a bigger space.

Came out a hefty 5.6 grams with a loop of 1/16" rubber. In the world of indoor planes, I would guess this to be sorta like a C130 carrying a load of tanks. With this kind of wing loading, maybe I can even fly it outside?? To be on the safe side I"ll wait till the wind is under 10 mph, though.

green air

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Old Feb 17, 2008, 11:32 AM
B for Bruce
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Oh, I definetly remember rollers. Not that I ever smoked. My own indoor days were back in the late 60's and early 70's when I was in my teens. So I pretty much qualify for "old curmudgeon" status these days....

It may take a while to get a model down to .6 grams but you'll be amazed at how quickly you will get to where you are down to under 1 gram. Oh, that's generally measured without the motor on the model just so we're all on the same page. Going to a covering film that isn't tissue will help a lot in that regard.

Writing paper is still pretty heavy. Look in the art or gift card store for some gift wrap tissue. It's not as crinkly as the stuff they call Jap tissue these days so it'll likely work pretty good. You won't be able to use Elmers though since the gift wrap tissue is like toilet paper and turns to mush around water.

What glue are you using for the joints on this model? That may be one place to save some weight depending on what you're using and how much of it.
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Old Feb 17, 2008, 07:58 PM
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Back in the 60's I use to work with a bunch of good ol southern boys, who all rolled there own. Some could roll a cigarette, with one hand, in 3 seconds. Smoked for a few years after High School, then gave it up, and took up skiing instead. A lot more fun.

Have been using elmers. Use Titebond mostly (RC stuff), but since very little sanding gets done on these planes (except maybe the prop) am using elmers, since it has no wood filler. The only other glues am familiar with is CA and 2 part epoxies. Got a feeling a lot of the excess weight is the tissue I've been using. Working on ezb #3 (mostly 1/32 stock for spars and ribs) the framed up wing weighed nothing on my scale, the tissue I cut to cover it with weighed .8 grams. When I finished the wing total weight of the wing, came to .8 grams. Have been using watered down elmers for the covering also. Yea I tried using tissue for the tubes, but using elmers it turned to mush like you say, that's why I went to the writing paper. So what glue do you suggest?

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Old Feb 17, 2008, 09:32 PM
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Ambroid if you can find it. Sigment if you can't. Then slip around to a plastics shop that does a lot of plexiglass work and buy a solvent bottle. It comes with a dulled off hypodermic needle for laying on solvent for glueing the acrylic. Squirt some Ambroid or Sigment into the bottle and add 1,5 times as much acetone to the glue. Stir it up and you're ready. You'll also want a syringe to clean out the needle at the end of each session. The syringe being filled with acetone and you remove the cap and squirt some through the needle to flush it clean. Then pull the syringe apart to let it dry so the rubber doesn't swell.

When I was doing this I didn't have the bottle so I used a syringe with glue and another that I'd flush out the needle with as per above except I'd just move the needle to the acetone syringe, flush and break down the acetone one and put the protective cap on the glue one until the next session.

What you're doing is using mostly solvent with just a hint of glue to build with. And that's truly all you need. For joints with significant gaps that you can't do anything about use a little dab of straight glue. This applies to things like the dihedral joints where you crack them and fill the crack with glue.

Even thinned elmers is very heavy as much of it will flow onto and into the wood instead of staying up where it needs to be. If you could actuall spread it thin enough you'd likely be better off with using it at full or near full strength. Keeping in mind you only need to use enough to wet the wood and not enough to actually soak into the paper. Now if that's what you're doing already then great. Another option I'd suggest is to try using one of the new style glue sticks. If you're careful to not let it blob it actually leaves a quite thin smear that stays on the surface where it's ready to receive the tissue.
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Old Feb 18, 2008, 01:37 AM
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Finished (more or less)

Am using thinned glue only on the covering. Have been double gluing (except on the covering) with the elmers. Will give ambroid and acetone a try. Is double gluing necessary with the ambroid? Don't know about the glue sticks, will probably stay away from them for the time being. Thanks for the help, appreciate it.

Found the wings, they were behind the TV. So here are a few shots of completed plane. Tried getting one in the air but the camera I got couldn't cope with the movements.


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Old Feb 18, 2008, 12:36 PM
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Joined Oct 2002
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She's looking pretty darn good from this angle. It'll be interesting to hear the flight reports and see some video.

There's so little stress in any indoor model that double gluing is just not needed and only adds weight for no purpose. Even a "starved" joint such as we get from using a thinned down cellulose glue such as the Ambroid or Sigment is more than strong enough to the point where the wood will break before the glue joint about 50% of the time and on the other occasions where the glue lets go it's a close thing. So don't fear to use a lot less glue. Test a few joints by glueing with amounts that you think won't work and a couple where there's a little more and so on. Then test break them. Keep in mind that the usual end to side grain joint will usually tear out a bit of the side grain on lighter wood. So use a magifying glass to study the end of the break. If you see wood fibers then the glue was strong enough. If you don't see torn out wood fibers then it was not enough. I think you'll be amazed at how little you need.
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Old Feb 18, 2008, 03:57 PM
Free Flight rubber flyer
South Carolina
Joined Mar 2005
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Eric, that's looking pretty good. I bet you can cut off close to a gram by switching to plastic covering. Even so, that plane should be capable of 3 minutes pretty easily under a 30' ceiling. With a little work, it'll fly ok in your living room, too.

And you asked about mine. Well here are some pictures. The one on the right is my 600 mg EZB, and the one on the left is an F1L (1.2 g EZB). The F1L will do about 9 minutes under a 30 ft ceiling if everything's in order. Something about that prop allows it to bump around obstructions without hanging up, so I can let it loose at pretty close to full power without worry of it getting stuck. The EZB would be able to do that, too, but the wing is too weak, and if it hits something, it can't seem to recover. I'm thinking of making a slightly stronger motorstick for it and a stiffer wing to see if that will allow me to bang it into stuff at will. One thing to note, my prop blades for the EZB are made from .006" C-grain balsa--that's so thin that you can read a newspaper through it. It's possible to sand wood down that thin, but I wouldn't recommend it. Go buy the stuff. And be warned that it's pretty challenging to work with. You need the sharpest razor blade you can get to cut it.

In the other photos, you can see the two models disassembled and then in the box with some of my other indoor ships. And I see that the wingtip is coming apart on my intermediate stick...
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Old Feb 18, 2008, 04:02 PM
Free Flight rubber flyer
South Carolina
Joined Mar 2005
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Eric, I just remembered that we had a cookup for EZB's over at SFA a while back. Have a look:
http://www.smallflyingarts.com/cgi-b...m=1164996610/0
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Old Feb 18, 2008, 06:55 PM
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Nice looking plane, erich!
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