Building a built-up pattern stab and wing
#52
Thanks Bob.
I thought since there is some down time waiting for glue to set I'd show the jig construction for this wing. This jig is slighlty different from past jigs, typically the jigs leading and trailing edge pieces are a solid straight piece from the table to the rib/leading edge. This jig has a horizontal former/spacer, a spine, that aligns the jig ribs to the elliptical leading edge shape, and then has 1/2" tall longerons top and bottom to prevent the jig ribs twisting when everything is pressing. Usually there’s some racking of the jig with the other jigs but this one is very stable and any future jigs may be built this way. The jigs are cut from 1/8" balsa to make them more durable.
Dave
I thought since there is some down time waiting for glue to set I'd show the jig construction for this wing. This jig is slighlty different from past jigs, typically the jigs leading and trailing edge pieces are a solid straight piece from the table to the rib/leading edge. This jig has a horizontal former/spacer, a spine, that aligns the jig ribs to the elliptical leading edge shape, and then has 1/2" tall longerons top and bottom to prevent the jig ribs twisting when everything is pressing. Usually there’s some racking of the jig with the other jigs but this one is very stable and any future jigs may be built this way. The jigs are cut from 1/8" balsa to make them more durable.
Dave
#53
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From: LiegeLiege, BELGIUM
Hello Dave,
It's a nice wood construction!
Keep posting pictures and descriptions.
Geoffroy
[link=http://www.lumay.be]my personal website[/link]
It's a nice wood construction!
Keep posting pictures and descriptions.
Geoffroy
[link=http://www.lumay.be]my personal website[/link]
#54
It appears the poly-u glue is the thing to use for a wood wing to attach the sheeting. I have a 42 inch wing panel to do on a scale Zlin 526. I'm assuming the open time is of no or very little consequence for attaching the skin? Any tricks to using the poly-u glue for this procedure? I've used poly-u on foam wings and like it very much for that.
Ken
Ken
#55
Hi Ken, I just use it direct from the bottle and put a small bead on the ribs and a larger bead on the spars, generally there is enough humidity in the air to activate the glue so I do not wet the wood. There's usually about 15 minutes of time to do the one side if the humidity in the house is not too hi but if the glue starts to foam slightly your time is very short to get it pressed. I do only one side of the panel at a time, by placing the skin being glued on the bottom gravity will hold the glue in position at the skin / rib joint.
Dave
Dave
#56
Both bottom skins glued on, trimming leading edge, installing aileron hinge doublers, installing servo box, installing solid balsa blocking for aileron stud and applying glue to attach top skin.
Dave
Dave
#58

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This is the fuse that Dave's new wing and stab will be attached to. It's the Mystic by Todd Schmidt. The weight of the fuse with the chin cowl and canopy are 28 ounces. I look forward to this an all American plane. There aren't many of those anymore!!! Thanks Dave it looks great. Mike Mueller
#59
Mike, it should be a good plane after it gets all trimmed out.
I had other things going today but was able to sand the leading edge and tip, match the panels and glue the leading edge balsa on.
Dave
I had other things going today but was able to sand the leading edge and tip, match the panels and glue the leading edge balsa on.
Dave
#61
This thread has been a real inspiration for me. I've been out of the hobby for 10 years or so and building techniques have change a bit! My Zlin has a near symmetrical airfoil at the root and and is under cambered at the tip with a good amount of washout. Seeing the building jig has inspired me to use the outside of the ribs (the part you throw away) to build a jig and then use the poly-u glue to bond the skin to the ribs. I was worried about how to go about this. Not anymore!
Thanks![sm=thumbup.gif]
Ken
Thanks![sm=thumbup.gif]
Ken
#62

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From: South Plainfield,
NJ
Hi All!
This is great stuff. For a slight twist on the technique, you might look up Bob Hunt's Lost Foam technique of building built-up wings and tails.
There is a video as well at Robins View.
http://www.airbornemedia.com/store/rv-lostfoam.htm
There is also a killer on how to mold compound curve balsa shells.
http://www.airbornemedia.com/store/rv-balsamold1.htm
Regards,
Dean Pappas.
This is great stuff. For a slight twist on the technique, you might look up Bob Hunt's Lost Foam technique of building built-up wings and tails.
There is a video as well at Robins View.
http://www.airbornemedia.com/store/rv-lostfoam.htm
There is also a killer on how to mold compound curve balsa shells.
http://www.airbornemedia.com/store/rv-balsamold1.htm
Regards,
Dean Pappas.
#63
I wish you luck Ken, it should be a blast to fly when done.
Thanks Dean, I think some of the fliers used a similar or that method around here in the early 90's, it worked really well. The nice thing about the laser cut parts is the repeatability and for lazy people like me no cutting of ribs or trying to cut foam.
Dave
Thanks Dean, I think some of the fliers used a similar or that method around here in the early 90's, it worked really well. The nice thing about the laser cut parts is the repeatability and for lazy people like me no cutting of ribs or trying to cut foam.
Dave
#64

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From: Mt. Pleasant,
OH
I'm enjoying the heck out of this thread. The jig looks like an improved version of the ones my dad used to build control line stunt wings about 60 years ago.
I'm also enjoying seeing a shop that looks like a shop and not an operating room!
I'm also enjoying seeing a shop that looks like a shop and not an operating room!
#65
Yes, a small messy shop.
Tip rough shape, rounding leading edge and tip, cutting aileron off / sanding and gluing aileron leading edge.
Dave
Tip rough shape, rounding leading edge and tip, cutting aileron off / sanding and gluing aileron leading edge.
Dave
#70
My part of the build is finished, sorry Mike I could not get you panels as lite as mine and I messed up somewhere in matching weights. Here is the finished wing on the messy table and the finished panels weights.
Dave
Dave
#72
Hey, Mike, you probably don't want to accept those panels. They are 2 gr different in weight. That's terrible..... VBG!!! Dave, that is fantastic, thank you for showing how you build the built up structures. Very, very nice. As far as your messy work space, mine looks like that all the time, I can't get anything accomplished if my tools are all put away in the right drawers and the glue is stored up in the cabinets.
Woodie
Woodie
#73

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Christmas is coming early boys!!!!! Wooo hoooo. That's really nice Dave. Thanks for living so near to me too. You've been so helpful over the years and I feel I and the whole Chicago Patterngroup benefits from your skills and innovative ideas. This is too cool. I'm very excited about having a new unique plane for next season.
One of these days I hope to beat you in a round or two just to make you feel a sense of accomplishment!!! Thanks, Mike Mueller
One of these days I hope to beat you in a round or two just to make you feel a sense of accomplishment!!! Thanks, Mike Mueller
#74

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ORIGINAL: mups53
Christmas is coming early boys!!!!! Wooo hoooo. That's really nice Dave. Thanks for living so near to me too. You've been so helpful over the years and I feel I and the whole Chicago Pattern group benefits from your skills and innovative ideas. This is too cool. I'm very excited about having a new unique plane for next season.
One of these days I hope to beat you in a round or two just to make you feel a sense of accomplishment!!! Thanks, Mike Mueller
Christmas is coming early boys!!!!! Wooo hoooo. That's really nice Dave. Thanks for living so near to me too. You've been so helpful over the years and I feel I and the whole Chicago Pattern group benefits from your skills and innovative ideas. This is too cool. I'm very excited about having a new unique plane for next season.
One of these days I hope to beat you in a round or two just to make you feel a sense of accomplishment!!! Thanks, Mike Mueller
Great job Dave. Can't wait to see the finished product!!Arch
#75

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From: Tracy,
CA
When was that scale last calibrated though Don A? haha.. 2 grams.. U R funny... Very nice work Dave and thank you for sharing this info with us!
Chris
Chris


