Skypup95.10

Hi to anyone whose interested. I have made a little progress since I posted the last images in the 'Skypup' Photo gallery on this site somewhere, last year. The trailing edge stock has all been planed to a tirangular profile. I used some very nice straight Hoop pine in lieu of Douglas fir. I have also planed down most of the cap strip material 2.5mm from a flitch of imported Orford (?) pine. The remaining eight 1'' Dow foam sheets have been reduced to 3/4" for the ribs and fuselage sides. I used a hot wire mounted in a rigid 3/4 spacer over the bench and pushed each weighted sheet along under it; each cut taking about 25 minutes. The spars for the empanage group have been fabricated. ie. Fin post and LE. Stab LE and spar. Rudder LE. Elevator LEx2. I have also made tree control horns from 2024 t3 Alclad sheet. Having trouble understanding how to load images here. So they will be in the Skypup album. Cheers Dete

Hi there, Thanks Scotty for the contacts, may come in handy. and DJH for the web links. I read most of the my wooden airplane stuff. Interesting, especially the abandonment of the first plane parts due to poor wood selection. I've had to learn that too. I bought a lot of Douglas fir and only one flitch was usable. I had to re-saw it to get the grain vertical as required. Thankfully I didn't use the fire wood. Not a lot of progress lately. I found I was missing the correct washes from my hardware order (from last year), final assembly of the wing attach fittings has been delayed. I got the washes today. Cheers

Hi John, I went through a long period of evaluating and trying to choose a building subject. I nearly started building a Woodstock glider (Jim Maupin design) and I studied the plans for a long time. It wasn't that it was very difficult, but the number of parts to be fabricated and the difficulty of sourcing timber etc (for the newbie builder) combined with the lack of space took the gloss of it, at the time, for me. I feel comfortable using wood and foam. I have built many r/c models so maybe that's why. The actual parts count of the Skypup is quite low, in spite of the fact that is actually a very traditional design and build. The only 'novelty' being the use of the blue foam to take the compression loads. When I (you) follow the building manual, the skills are built upon as work progresses. I'll take a look at that blog, thanks. Cheers

Hi DJH, Thanks for the encouragement. I'll keep posting pictures from time to time if there is interest. If some day comes, you may choose to build a Skypup. There are many things to learn when building from plans rather than a kit. Cheers

Hi there all, I've made a little progress over the last two weeks, in spite of the cold temperatures here in Sunbury. Not to good for gluing. Still working on the spars. After making cardboard patterns for the webs and and tracing them onto the Birch ply, I then removed the bits that didn't look like a Skypup with the jigsaw. After gluing the webs on one side only, I trimmed them to size with a small plane. There are some new photos in my Skypup gallery which show better than words can say. The long reamer was an idea from a model engine friend. It was very useful in aligning and sizing the quarter inch holes exactly. Used at low speed and kept very sharp with a fine diamond ezi-lap stone. I'll repeat the gluing and match drilling for the webs on the opposite sides next. Building a plane is all consuming at times but I'm really enjoying it at the moment.:big_grin: Cheers

Hi Winsor68, Yes, there is a lot of Blue Foam (Dow TM extruded polystyrene - not expanded) and it is used in compression between the spar caps of the Wing, Fin post, Rudder and Elevator spars. Also, in the fuselage sides between the upper and lower longerons and for the wing ribs, which also have wooden cap strips. I have considered the large (210 cc) model engines but they offer no price advantage tho' they are very light. They tend to rev quite high and are not suited to turning a 50" prop at 2,500 rpm. I think the paraglider engines, that come with a reduction drive and designed for high thrust low speed applications are a better bet. The original 'blue light special' from which the Skypup evolved, was flown with 15HP. I estimate I will spend under $1200 on the finished airframe. $3500 for a new engine and $300 on instruments. This is using all new materials and parts. Cheers and thanks for your interest.

Hi Shane, I'm an ex hang glider pilot as well, so all I can say is hundreds of people fly this way each weekend. Its no better or worse , just different. By the way I had no trouble jumping from three axis to weight shift and back regularly. Keep an open mind and just fly any way you can. Cheers

Hi all again, Its raining so I'm back. Success with loading the pics I took today. They are in a "Skypup" album in the Gallery. Cheers

Hi all again, Thanks for the interest, I had no idea that anyone else would care. I've been spurred on a great deal by the comments made. I took some photos today to upload. Unfortunately they are too large to be sent so I'll try again tonight. In answer to some more questions raised above, yes Winsor68 they are the plans of the Skypup. They come with a construction manual of about 20 pages that you can't do without as the manual contains some vital details and information not drawn on the plans. Cheers

Hi Bandit12, From all accounts the lack of ailerons is of little concern. Like the early Eiper's and many model aircraft, they just don't realize that they have none. The dihedral of 6 degrees under each wing panel creates a strong secondary roll effect when the plane is yarwed using the rudder. Its like co-coordinating both controls together. Having said that, there are limitations off course there is no ability to use 'crossed' controls like side slipping and cross wing landings and take offs are a no no. Its a very stable flyer by all accounts but not for windy weather. No doubt I'll find out for myself in good time. Cheers

Hi John, Yes, its a lovely engine and I did have a look at it some time ago. You were right to identify it as a "perfect fit" with the Skypup but at 3500 stirling pounds (about $9000 Aussie) I don't think so.

Thanks to Guernsey (ah, its Alan) and Ed for the warm welcome and interest. You've put a smile on my face too. The engine choice is quite difficult for a lightweight (200lb empty) plane like this. Originally most were flown with cuyuna 210 single, 21hp and perfect. (now built by 2SI but unobtainable in Aus). Some have now got a rotax 277, 28hp and bit too heavy, vibrate, and also out of production. I think one of the best engines are the Hirth 313 or the MZ34. Both are similar 27-30hp and 17-23kg depending on options. I think I'll go for the MZ (lighter) but like the Hirth it has a radial mount and this will require some airframe modifications so that it can be mounted on a firewall. The Skypup is designed with a beam mount. At the moment I'm head scratching about that and the C of G because it will require moving the engine forward to preserve foot space. Change one thing and it has a domino effect. I'll deal with the details later, as there's plenty build in the meantime. David asks about steam bending. No, but the upper fuselage longerons are 2 peices and laminated in place to help ease the bend. They are douglas fir. I'm using West systems epoxy throughout. I will post some pictures from time to time when I work out how its done. I expect to be enjoying this for the next year or so. Cheers and Thanks

Hi all, Looks like a nice place to hang out. I am from Sunbury and I am building a Skypup. If you would like to know more do a google search as there is good builder support on the web. Try 'Machnone' or skypup yahoo group. I have the centre wing spar done and I am working on the main wing spars. All hardware and most materials are now bought. I don't think many people like to build in wood these days but I love it, it's just like a model plane only bigger. Anyhow Best wishes.