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Mikeb52

Hi -phase CG needed.

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Mikeb52

I am installing 2.4 gear in my old lovely built up wing hi-phase. But I seem to have lost the CG! Anyone have an idea, what it is. 
thanks in anticipation. 
Mike. 

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SilentPilot

No idea what the actual CG is for that particular glider but do you still have the old (35mHz?) gear available to you?

I'd put all that back in as it was and measure the resulting CG then if it looks about right put in the 2.4 and arrange things to keep that same CG :) 

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Mikeb52
2 hours ago, SilentPilot said:

No idea what the actual CG is for that particular glider but do you still have the old (35mHz?) gear available to you?

I'd put all that back in as it was and measure the resulting CG then if it looks about right put in the 2.4 and arrange things to keep that same CG :) 

A nice idea, but the 35 meg gear went years ago. 😕

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Mikeb52

I’m waiting for Pete Beadle to see this post. I’m hopeful he will know. 🤔

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Stormeflyer

Hi Mike

Someone on RCgroups suggests he found the sweet spot to be 2 5/8",  He tried it as far back as 3" but described it as "interesting".  
Start at 2.5 inches to be safe!

 

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pete beadle

Hi Mikeb52

I am humbled by your confidence in my depth of knowledge on these matters:)

However.....in this instance, you're in luck! I usually describe the CG  on my Hi-Phase as "just in front of the rearmost wing joiner tube" viewed from the wing root - for those of you who wish me to be a bit more precise........ as 13 cm from the LE at the root, OK?:thumbsup:

Regards

Pete

BARCS1702

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pete beadle

Hi all

I've just seen Stormeflyer's post.....IMHO 2.5" from the LE  would make the Hi-Phase  hopelessly nose-heavy......are you sure that figure is for the Hi-Phase? It might work with a MultiPhase or a Phase 6 but the Hi-Phase wing has a very  distinctive sweep-back:yes:

Regards

Pete

BARCS1702 

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Stormeflyer

Hi Mike/Pete

Apologies for the duff info 😳

The thread I read was High Phase but you are right Pete, it did indeed refer to a middle phase 👍

 

22C4E6E3-49DB-4272-A96F-DDCF1CE7E5F1.jpeg

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Mikeb52

thank you Pete, I knew you would know! 

Mike. 

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Gary B

The CG varies slightly depending on the version, the 1982 plan above has the fin raked further back to give 2" more moment arm.

My Hi-Phase was built from scratch using a battered Centi-Phase fuselage, the CG is marked on the plan (1980) and I make it 127.5 mm or exactly 5".

Can't remember but I'm sure I set it up at this position, it could probably go back a tad as the elevator isn't very effective on landing, just about rounds out with the spoilers open.

I remember being puzzled when I finished building it that it was nose heavy, I had to move the Rx battery to under the wing joiners.

 Cheers

     Gary

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1915055949_PictureorVideo223.thumb.jpg.4869c9a3616e3fe6d2b943856cc88f2e.jpg

 

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pete beadle

Hi all

Back in the day, Chris Foss offered a built-up wing version of the (usually) foam winged  Hi-Phase, the plans were ENORMOUS and I just HAD to build one! So, as winter drew on that year (in the late 70s - early 80s) I cleared the building room (my bedroom and a base for a model railway layout in the hallway ) cut up the plans and settled down to some serious rib cutting and sanding to shape. Fortified most evenings by Mum's late night toasted cheese and pickle doorsteps, November, December and half of January passed into history. Then, one evening in mid-January I revealed the beautiful wing panels to the family and asked to borrow Mum's kitchen scales........I weighed these lovely creations and found that they weighed almost exactly what the foam wings weighed! Merde!

A few days later, on a crisp and cold morning, I launched the Hi-Phase on my EMP surgical rubber bungee to a quite respectable height and waited for the difference in flying qualities of the built-up wings to appear, to show me that all the blood, sweat and tears (great band!) of the winter hadn't been for naught!

NOTHING! No difference whatsoever! Ah well, at least I hadn't been wasting my money by going out all that time.........but, oh!, what a disappointment:(

Regards

Pete

BARCS1702 

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SilentPilot

Great job anyways, Pete!

I wish I had the patience (and skills) to make a built up wing. 
Alas, no I don't. My dad does most of my building and repairs but I don't like bothering him anymore. I'd much prefer to learn how to build and fix things myself, but please refer to the lack of skills mentioned earlier :(

Just as a side note...
I once had a Race Rat, Graupner if I remember correctly, which we just couldn't get to fly. This was back in the day of brushed motors and Nicads so the darn thing just got too heavy. In the end dad extended the wings and added some forward sweep to get it flyable.
One day we had to take it to our model shop, can't quite remember why, maybe to get some new batteries for it. The shop owner recoiled... WHAT HAVE YOU DONE - IT'S NOT A BLOODY MOTORGLIDER.
Sorry! But we needed to get it flying one way or another...

Now it has a brushless motor and LiPo setup. And needed a longer nose to balance properly :D 

Flies bloody well now too. Might have to clip the wings again!

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Tony
1 hour ago, pete beadle said:

Hi all

Back in the day, Chris Foss offered a built-up wing version of the (usually) foam winged  Hi-Phase, the plans were ENORMOUS and I just HAD to build one! So, as winter drew on that year (in the late 70s - early 80s) I cleared the building room (my bedroom and a base for a model railway layout in the hallway ) cut up the plans and settled down to some serious rib cutting and sanding to shape. Fortified most evenings by Mum's late night toasted cheese and pickle doorsteps, November, December and half of January passed into history. Then, one evening in mid-January I revealed the beautiful wing panels to the family and asked to borrow Mum's kitchen scales........I weighed these lovely creations and found that they weighed almost exactly what the foam wings weighed! Merde!

A few days later, on a crisp and cold morning, I launched the Hi-Phase on my EMP surgical rubber bungee to a quite respectable height and waited for the difference in flying qualities of the built-up wings to appear, to show me that all the blood, sweat and tears (great band!) of the winter hadn't been for naught!

NOTHING! No difference whatsoever! Ah well, at least I hadn't been wasting my money by going out all that time.........but, oh!, what a disappointment:(

Regards

Pete

BARCS1702 

But Pete toasted cheese and pickle doorstops by your Mum absolutely priceless and no doubt telling you not to strain your eyes nor stay up too late

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