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May 24, 2019, 08:47 AM
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whacker:

For the conventional tail on both versions of the Slite, the horizontal tail mount is almost identical. Both are a stack of balsa and thin ply; both fit down over 2mm carbon posts into pre-drilled holes for perfect alignment; both are contoured by means of CNC routing to suite the boom.

Most importantly, both are CNC-routed to fit the underside of the horizontal tail. However, the horizontal tail on the V1 Slite is FLAT, not contoured, so matching that profile is easy.

I believe that Gruener simply modified Josef's basic solution for the horizontal tail mount. It is elegant, simple, nearly fool-proof and combines light weight with low drag. I have used similar mounts many times over the years, while I was busy learning F3K.

Neither is as elegant, simple or light weight as the mounts for the V-tail: two, 2mm carbon rods that fit into 3mm carbon tubes that form the spars.

Yours, Greg
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May 24, 2019, 08:55 AM
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Both are Covered


It was very, very windy yesterday, and no one was around to assign other chores, so I was able to finish covering the Slite V1.

Enjoy the pictures. No comparative weights or CG, as the guts are not yet installed in the V1. It comes supplied with the materials necessary for pull/spring.

I have enjoyed this build very much. The folks that purchase the new Slite are in for a treat, I think. Every component (except the tail surfaces) come out a bit heavier, mostly due to materials choices. The Version 2 parts count is slightly reduced, and I think some of the design details are simpler than Josef's. Execution and fit-and-finish on both are simply marvelous.

There is a slim chance for a first flight on the V1 Slite tomorrow, plus more trimming on the V2 with new, adjusted CG (which may necessitate shimming the tail, maybe).

Greg
May 24, 2019, 09:02 AM
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whacker's Avatar
aah, OK thanks

adjusted CG (which may necessitate shimming the tail, maybe).
Should be interesting to see if your gonna try a shim here or there on the aft end of the tail where it meets the perch.



whacker

in cldy NS
May 24, 2019, 11:11 AM
Hates Palm Trees
Great looking planes as usual!

Steve
May 24, 2019, 11:06 PM
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Thread OP
I flew the Slite V2 again today, and the forward CG placement helped a lot - it showed lift well and stayed in thermals well - well enough that I scored three 1000s and a 993 in an informal contest this morning. Time to take the push rods out, and replace them with lighter pull/spring systems! The new weight and CG is a porky 17oz/476g, and the CG is at 76mm (right in the middle).

When I came home, I installed the guts into the Slite V1. It weighs a fire-breathing 13.4oz/375g, and that is with no lead in the nose at all. CG is 78mm, probably right at the normal aft limit. Tomorrow, I may have a chance to fly it, and I will drop a lucky quarter in the nose, and do just that.
May 25, 2019, 05:20 AM
FinnK
English is not my native language so I have to ask if you mean 476g is to much for this glider or what. Yes, I can see that the V1 is extremely light. :-)
May 25, 2019, 08:37 AM
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FinnK:

My experience with these airplanes is that 420g is what I have come to expect. More than that, and I feel disappointed. My initial professional experience in aeronautics was that ANY excess weight is bad, and that no airplane ever suffered from weight savings. I get obsessive about weight in airplanes.

Make no mistake: the Slite V2 performed well for me yesterday. I only wish it did not weight so much. There are a number of opportunities for weight savings. I intend to buy another and try some. In the meantime, I am very excited about this example (my last, most likely) of the Slite V1.

Yours, Greg
May 25, 2019, 04:19 PM
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Larry Jolly's Avatar
Dear Greg
I appreciate your observations very much, and admire your perception and analysis. However imho your conclusion is to general for those of us reading this to follow your thoughts. Since flight performance is not limited to a single maneuver, but instead a number of sequential steps perhaps you could compare the differences between the two Slites in a more complete format. Suggest starting with launch- circling- climb- covering ground- landing- and then apply a rating based on those aspects. What I have read so far is interesting, but to subjective for me to follow.
Thanks Larry
BTW of interest are the physicals comparable?
May 25, 2019, 04:33 PM
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Billh178's Avatar

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Ordered my Slite V2 last Sat from Hyperflight, it was dispatched on Monday and arrived on Thursday.
I was expecting at least 10 days or more. Canít wait to start on it. I have a question.. according to Hyperflight it is laser cut,
Upon inspection mine doesnít look laser cut but punched out, all parts have a small tabs connecting the part to the sheet of wood. Is this kit die cut or laser cut. I had just finished the YJ3M which was laser cut Iím curious if the Slite kit I have is correct?
Thank you,
Bill in Vegas
May 25, 2019, 06:39 PM
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Thread OP
Bill:

Your Slite is indeed laser cut. Unlike Corky, the Gruener crew leaves to parts in the carrier sheets for transport. Look close at the edges: they should appear dark and burnt. I use a box cutter to remove the parts from the plywood, and a razor blade to remove the balsa parts. A quick pass with a sanding block is all it takes to remove the nubs.

And... Having said all that, there are still some CNC-routed parts. mostly the nose blocks and other thick pieces. Those are also retained in their original thick balsa stock.

Yours, Greg
May 25, 2019, 06:43 PM
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Thread OP
Larry:

Point taken, and as a matter of fact, I was able to make the initial flights on my latest Slite V1 just this very morning. I threw it a few times, but then the wind rose too high to risk using the hi-start. My next opportunity to fly it will most likely be Tuesday.

I really want to directly (and objectively) compare the two airplanes.

Today, at the sod farm, I got to throw the V1 Slite, and it is pretty good. Of course, I have expectations for it, having flown more than my share.

I'll get there!

Yours, Greg
Last edited by glidermang; May 25, 2019 at 07:03 PM.
May 25, 2019, 07:02 PM
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And now, more flying experience with the V2 Slite.

We had an impromptu contest yesterday: everybody got four tries at a 6-minute flight, plus points for a simple target. I got pretty near six minutes each time, launching into soft and variable lift, with two launches actually down wind, but the airplane was still able to find, indicate and work the light lift. Very impressive, and much improved over the previous outing. I had the CG much closer to the design location, and it showed. At home, I weighed the airplane again, and here is where it was: 475g/17oz, at 76mm aft of the wing leading edge.

I took the airplane wit me today to the sod farm. The wind rose, but the hi-start was out, and I put it up. Launch was very good, and while the wind quickly rose past about 15mph, the airplane handled well enough that I never had to walk very far to pick it up. I am happy with how this airplane flies and handles, although I will still try a few changes. In the meanwhile, when I got home, I thought "Life is too short to fly a heavy airplane", so I replaced the rudder push rod with a pull/spring setup.

The pictures tell the story and show the process.

Removing the push rod and installing the pull/spring saved a whopping 4g. Yeah, I'm not impressed either. However, to get the CG back to the 76mm, I removed another 8g from the nose. If I can do the same for the elevator, we are now looking at a nice savings. The horizontal tail is made of many light pieces. I am looking at and think I can put in the torsion springs, but it will take a while before I try it.

Now, the current weight is 462g/16.5oz, and the CG is still at 76mm.

The other heavy component on the airplane are the wing joiner rods: 4mm steel rods. They weigh over an ounce together, so replacing those with composite is an attractive idea. Also, they are way out there in the wings, and a more responsive airplane is always nice, I think. They are embedded in epoxy, but my friend Kirby (a jeweler and metalsmith) says he can pull them out without damaging anything.
May 25, 2019, 07:28 PM
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Billh178's Avatar
Quote:
Originally Posted by glidermang
Bill:

Your Slite is indeed laser cut. Unlike Corky, the Gruener crew leaves to parts in the carrier sheets for transport. Look close at the edges: they should appear dark and burnt. I use a box cutter to remove the parts from the plywood, and a razor blade to remove the balsa parts. A quick pass with a sanding block is all it takes to remove the nubs.

And... Having said all that, there are still some CNC-routed parts. mostly the nose blocks and other thick pieces. Those are also retained in their original thick balsa stock.

Yours, Greg
Thanks Greg, now to clear of work area and get started!
May 25, 2019, 08:39 PM
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R.M. Gellart's Avatar
Quote:
Originally Posted by glidermang
The other heavy component on the airplane are the wing joiner rods: 4mm steel rods. They weigh over an ounce together, so replacing those with composite is an attractive idea. Also, they are way out there in the wings, and a more responsive airplane is always nice, I think. They are embedded in epoxy, but my friend Kirby (a jeweler and metalsmith) says he can pull them out without damaging anything.
That is why I went single piece wing, I looked at those joiners and just thought they were really not an advantage of any sort. Must admit that I have chased the absolute weight target on other sailplanes, and have never seen much advantage except breaking them, unless the ship was a total hog. In Ohio, the breeze is pretty normal except in early morning, so I am not worried about it, and string and springs IMO are just ways to wear out servos and drain batteries faster. We will see, maybe fly the ship this week if weather window happens.

Marc
May 29, 2019, 09:05 PM
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Thread OP
I have been having quite a time the V1 Slite.

I flew it last Saturday at the sod farm, giving it a few tosses before the main event (which was a club fund-raiser, to send two of our members off to FAI World Championship contests. Toby goes to the World's for F3K, Skyler to the World's for F5J). It flew fine (and I added a half ounce to the nose), but as I walked it in, the spoiler servo announced just how unhappy it was with the world, then all the smoke leaked out. The nest unflyable day, I removed it and replaced it with a D47.

So, the past Tuesday, I tried to get out before the wind came up too bad, threw it a couple of times to verify it was still working correctly, when a wind gust picked it up near the ground, and turned it on a wing tip. The wing joiner between the intermediate and tip panel broke, and I had to take it home once more. I pulled the covering off the right outer wing, and the repair was simple once the tip was separated from the intermediate panel..The repair is done, but now I'm waiting for a shipment of Transparent Red Ultracote!


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