IMAC Double Build, Carden Pro 124" Extra 300 40%
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thank you! We had those as left over when we built a deck in our back yard. It is Coral Stone from the Dominican Republic. In the summer, it does not get hot, and it is a non slippery surface.
Here we are, some more good news, my plan worked!
Now, you can see, how that slot in foam (at the end of the wing tube phenolic) is totally filled with balsa, and the grains of the balsa, I placed it, so they are perpendicular to the surface of the wing.
I also filled that small gap with balsa.
Here we are, some more good news, my plan worked!
Now, you can see, how that slot in foam (at the end of the wing tube phenolic) is totally filled with balsa, and the grains of the balsa, I placed it, so they are perpendicular to the surface of the wing.
I also filled that small gap with balsa.
Next step, is to glue on the root caps. here is my technique. I do it, one by one, so it will take a while. No need to post pictures of the other ones, just the 1st one. However, if anyone wants me to show any more, I sure can.
I should digress and make a short explanation as to the method for the phenolic support.
I have read, and heard pilots, discuss the phenomenon of the foam core wings that fatigue fail, during flight, and with usually a catastrophic result. I have also seen some pictures on the forums, and usually, this failure occurs at the tip of the wing tube.
In general, the closer to the fuselage, the higher the forces on the wing, however, from the fuselage to the end of the wing tube, this area is reinforced by the wing tube.
In other builds, attempts have been made to address this, including different options: 1. reinforcing the wing with carbon fiber tow. 2. reinforce the wing with square carbon fiber rod from root towards the tip, on bottom and top of the wing, or 3. reinforce same way, but with a spruce square rod.
The manual for the Carden has this idea, of using a balsa spar extension, that overlies the "stress riser" area.
I probably did not have to fill that hole with balsa, but felt obliged, as the extensions will span that "stress riser" area.
wings #1, root of the wings, with hard points and phenolic glued on
root cap with wax paper
wax paper over the fuselage, to protect it and prevent it from being glued
wing is now on the root cap and on the fuselage side.
reason for this, is so that the wing root, presses down on the root cap, and this helps to minimize gaps between the wing root cap and the fuselage sides.
I should digress and make a short explanation as to the method for the phenolic support.
I have read, and heard pilots, discuss the phenomenon of the foam core wings that fatigue fail, during flight, and with usually a catastrophic result. I have also seen some pictures on the forums, and usually, this failure occurs at the tip of the wing tube.
In general, the closer to the fuselage, the higher the forces on the wing, however, from the fuselage to the end of the wing tube, this area is reinforced by the wing tube.
In other builds, attempts have been made to address this, including different options: 1. reinforcing the wing with carbon fiber tow. 2. reinforce the wing with square carbon fiber rod from root towards the tip, on bottom and top of the wing, or 3. reinforce same way, but with a spruce square rod.
The manual for the Carden has this idea, of using a balsa spar extension, that overlies the "stress riser" area.
I probably did not have to fill that hole with balsa, but felt obliged, as the extensions will span that "stress riser" area.
wings #1, root of the wings, with hard points and phenolic glued on
root cap with wax paper
wax paper over the fuselage, to protect it and prevent it from being glued
wing is now on the root cap and on the fuselage side.
reason for this, is so that the wing root, presses down on the root cap, and this helps to minimize gaps between the wing root cap and the fuselage sides.
Just finished with sanding the wing root caps flush with the foam wing surface. (recall, I will do the sheeting so that it locks the root cap in.) For wings #1, next step is sheeting.
I will do the step prior to this to the next set of wings (Carden #2) , and then to the Dalton wings (once the phenolic arrives), and then I can sheet all 3 wings at once.
I will do the step prior to this to the next set of wings (Carden #2) , and then to the Dalton wings (once the phenolic arrives), and then I can sheet all 3 wings at once.
Rusty 73
100cc
Your one busy builder , I like how the wing is taking shape . Getting back to reinforcing , using a carbon fibre spar you would have to have one that is tapered smaller to the tip to reduce the stress is at the tip as compared to having it thicker at the root closer into the fuselage . Like you said there's more load near the root section of the fuselage than at the tip ,so the spar has to be tapered making it smaller at the tip , just like a really aircraft this allows the wing to flex . If it's too stiff then then wing tip near the end could just compress and partly fail !! It needs to flex but not break like a birds wing.
That stone from the Dominion Republic sound like the same stone at our resort in Dreams LaRomano we visited , not slippery and stayed cool in the heat
That stone from the Dominion Republic sound like the same stone at our resort in Dreams LaRomano we visited , not slippery and stayed cool in the heat
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I have 28 flights and 6.4 hrs on my PRO! I have the trimming out done! Last weekend we adjusted my throttle curve. The curve makes me feel very comfortable flying the PRO. Makes throttle control much easier than it was!!
In fact, my flying buddies liked my throttle curve so well that did one on their TXs too!!
got a little bit more done today.
Both sets of wings have the root caps glued on, and they are contoured to the fuselage sides.
I also found the directions or recipe, as you may, to cut out the ailerons:
the next step, will be to start planning on the location of the servo lead tunnel, servo boxes, and where to cut out the ailerons, and place the hard points.
Both sets of wings have the root caps glued on, and they are contoured to the fuselage sides.
I also found the directions or recipe, as you may, to cut out the ailerons:
the next step, will be to start planning on the location of the servo lead tunnel, servo boxes, and where to cut out the ailerons, and place the hard points.
Need to give a bit of credit to Dave Dixon for having shared with us his template for the stab root cap.
Very nice indeed.
I printed it out at 35% magnification, and it was dead on for the 2" reference line.
I will be making 4 of these caps...
I drilled the location for the spar (stab tube phenolic hole) and the tab holes.
hole was made with a circular saw.
capping the phenolics with 1/16th balsa
trial fitting of the phenolic with the root cap, and then I checked, to make sure, the tab holes will be in line with the hard points there.
over the next few days, I will be gluing in the phenolics into the stabs, with the hard point for the anti-rotation pin in the stab root. Soon, I will be sheeting all the wings and the stabs, then I will set the incidence on both, before I proceed.
Very nice indeed.
I printed it out at 35% magnification, and it was dead on for the 2" reference line.
I will be making 4 of these caps...
I drilled the location for the spar (stab tube phenolic hole) and the tab holes.
hole was made with a circular saw.
capping the phenolics with 1/16th balsa
trial fitting of the phenolic with the root cap, and then I checked, to make sure, the tab holes will be in line with the hard points there.
over the next few days, I will be gluing in the phenolics into the stabs, with the hard point for the anti-rotation pin in the stab root. Soon, I will be sheeting all the wings and the stabs, then I will set the incidence on both, before I proceed.