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Old Apr 07, 2009, 11:09 AM
It was a GLITCH! Honestly!
SafeLandings's Avatar
Stourport on Severn ,Worcestershire, United Kingdom
Joined Dec 2007
4,822 Posts
Next I made up some tip weights using plumbers solder, each weight weighs 9 grammes and is then folded in half and squashed up in vice jaws (the jaw marks will help the lead adhere to the balsa )
I then measured 15mm (on the underside)from the tip and marked out the position of the lead tip weight, making absolutly sure its centre line lies on the blade CG. Its just a case of cutting out a slot for the weights making sure they are a nice snug fit, they were then epoxied into place.
I then measured 580mm from the tip and mark my mounting hole, again along the cordwise balance point, hopefully this hole will match up with the hardwood blocks!!
The blade tips were then hardened up with CA and balanced in the normal way!!...easy!!

Just follow Mike tips on his web page for covering instructions here

http://www.aerobalsa.com/finishing.php

Hope this helps

Regards Rich
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Old Apr 07, 2009, 11:16 AM
It was a GLITCH! Honestly!
SafeLandings's Avatar
Stourport on Severn ,Worcestershire, United Kingdom
Joined Dec 2007
4,822 Posts
RPG Mk I now repaired and covered and MKII to the left uncovered, red is all I have left and is the left overs from the DAG ic build just completed ....yes ...I m tight!!
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Old Apr 07, 2009, 02:44 PM
autogyro andy
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South UK
Joined Feb 2007
725 Posts
A work of art Rich, well done.

Andy
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Old Apr 07, 2009, 04:30 PM
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Joined Nov 2004
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A minor point...

A minor point. Finding the blades CG, and applying weights at that point (for and aft chordwise that is) and putting the attachment bolt at the same point, doesn't automatically make the blades stable. I believe that you may be better off putting the bolt hole at 25% of the chord and putting the tip weight in the leading edge. Doing these things will tend to make the blade be nose heavy and be more stable.
Just food for thought.
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Old Apr 07, 2009, 05:25 PM
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DeRidder LA.
Joined Nov 2008
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Rich,
That's incredibly helpful, thanks so much. My AB blades are already enroute from AB! I presume this is the same method you used for the prototype two blade build; if so, the performance is exactly what I hope to have with my RPG.
Do you make the top and bottom plates just as you would the three blade plates in the plans?
Regards,
-Mike
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Old Apr 07, 2009, 11:15 PM
AND FOR MY NEXT TRICK....!
jodini's Avatar
Omaha Millard, Nebraska, United States
Joined Sep 2004
4,061 Posts
Thanks Rich,
When my new blades come in I'll follow the steps! In the mean time, I'm going to try my aerobalsa blades with 12 oz of weight and hope to have some luck. Suppose to be a nice day tomorrow!
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Old Apr 08, 2009, 10:47 PM
Flyin Low
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Simi Valley, Calif
Joined Nov 2007
229 Posts
RPG Plans

Quote:
Originally Posted by thebrown
OK. Was hopeing it might happen! Where can I find plans to at least make up some Dag blades and three blade head up while I'm waiting. Any help would be much appreciated.
This might help http://home.att.net/~imsofaman/wba.htm
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Old Apr 09, 2009, 06:44 AM
It was a GLITCH! Honestly!
SafeLandings's Avatar
Stourport on Severn ,Worcestershire, United Kingdom
Joined Dec 2007
4,822 Posts
The plans wont be available for a while due to a few problems people are having..we just need to get over these obstacles first..I want to get it right so that it is successful for everyone



So I have finished repairing the Prototype and she is now ready to fly again but the weather is not so good over here ..This 'minor' glitch that I have had has given me time to strip down the RPG and check for any weakness or wear in the stressed parts, I had a little bit of wear in the front wheel bearer but I have epoxied a brass insert into the hole so this should help. Apart from that the RPG seems to be very durable (unless you hit the ground at full speed from inverted!! )

Here are a few pictures


Regards Rich
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Old Apr 09, 2009, 06:54 AM
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Nowhere
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She looks great Rich!!!

Dave
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Old Apr 09, 2009, 07:00 AM
AND FOR MY NEXT TRICK....!
jodini's Avatar
Omaha Millard, Nebraska, United States
Joined Sep 2004
4,061 Posts
The RPG looks great!
However Barbie looks like a beaten up house wife.....her hairs a mess, brusies from the last crash and her clothes... ! MAN...send her out to the beauty salon Rich!
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Old Apr 09, 2009, 10:12 AM
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DeRidder LA.
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Hello Rich,
She looks good as new man! I like the balsa filler at the top mast too, cleans it up very nicely. When we have pilots that bang up our full scale aircraft in the Army, they get a review board to see if they should continue flying or not. Are you quite certain Barbie should keep flying?

Regards,
-Mike
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Old Apr 09, 2009, 03:04 PM
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Joined May 2008
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Wow!!!! that RPG MK2 looks just about ready for the next crash (ahem!! close encounter with the earth)

See you at the field Heli is primed and ready, heli is also very pleased to have a new play mate, but could Barbie have her hair colour changed as heli is now not so sure about having any faith in a blonde being in control of the new RPG.

P.S. As usual all sympathy will be left at the entry gate



Andy
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Old Apr 09, 2009, 03:36 PM
It was a GLITCH! Honestly!
SafeLandings's Avatar
Stourport on Severn ,Worcestershire, United Kingdom
Joined Dec 2007
4,822 Posts
LOL...hopefully see you tomorrow for round 3!!...weather looks like it will be crap


So...I have been up North today and delivered Steve Webbs R1..a very nice chap who is a very ill man ..but he loved his new Gyro and will hopfully fly it if and when he feels better.
On the way up I diverted across to meet up with Richard Bavin, a keen modeller who has built 2 DAG's and 1 RPG..I took along my RPG for a 'photo shoot'..its supprising how the wire UC makes the plan built RPG look bigger!
Dont worry ..Barbie is still in a very fit state to fly!..even though she now only has one arm and no legs..LOL


Regards Rich
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Old Apr 10, 2009, 05:20 PM
It was a GLITCH! Honestly!
SafeLandings's Avatar
Stourport on Severn ,Worcestershire, United Kingdom
Joined Dec 2007
4,822 Posts
Well the first flight after the rebuild didnt quite go to plan..infact it lasted around 20 seconds!!
It took alot longer to take off this time and I had to hold alot of rearward tilt..it didnt feel right as soon as it was off the ground? very sluggish in roll
It did climb away but felt very heavy so I tried a left hand turn ..it turned but the nose dipped down and there was nothing I could do to recover!!...SPLAT..it went in real hard.

So my feeling is ..I know the blades were heavier than the orginal set but I still used the same amount of tip weight, they are also a lot stiffer than the last set.
I think that my servos were struggling to pull the rotor disc over, I also had more hang angle by moving the battery even more forwards in the fuz than before.


Conclusion:

It looks like the 2 blade head for the RPG is very critical to get correct...anyone who is thinking of doing this head..please stop!!..go with the 3 blader until I have found the cause of this smash..Im thinking that it is the blades total weight and not the tip weight mass.


Its a good job someone sent me some CA!!


The original head was just lucky I guess


Regards Rich
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Old Apr 10, 2009, 06:00 PM
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Rich, so sorry to read that the two bladed RPG hit the deck really hard. I hate when I crash a gyro.

So....what will you do now? Can you fix it? Going to make another set of 2 blades?

Hang in there man!!!

Dave
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