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Yuppy Love


Levanter
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My girlfriend is an enthusiastic supporter of my hobby and thoroughly approves of the growing fleet adorning the ceiling in our flat.

I have a growing collection of Peter Miller plans so one evening, completely without any need for a new project, I gave her the pile of plans and choose one. Very quickly she narrowed it down to Yuppy Love. So here I am, committed.

A quick search on Ebay got me the 1992 magazine with the instructions and off we go.

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Here is what the model looks like although I have a very different colour scheme in mind.

yuppy-01.jpg

And here are the rib blanks cut out

p1110272.jpg

It will be powered by a Magnum 15. Using Peter's own words, it is quite slippery but now with the availability of small servos I can follow his suggestion to have ailerons on both wings as well as having flaps on the lower wing. This will make it an interesting challenge. Supposed to be a quickie before the 2015 Mass Build. We'll see!

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Hi Levantor3.

IT is a nice model. So nice that I did bigger version called Toot Sweet and at the moment I am building a similar aircraft for a .40 FS.

A little story. Many years ago I was looking round a DIY store and spotted a folding decorating table. The box showed a model aircraft and I thought "That is a pretty looking little biplane....That is a familair looking biplane....THAT'S YUPPY LOVE!!! and it was a painting of the model including sections of the plan.

Now if the commercial artist had asked if he could use I would have said "Yes" but can I have the artwork when they have finished with it. But he had not. so I am afraid it cost him some cash!

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Good progress today. Here are the ribs ganged up for final shaping and sorting out the spar slots.

p1110274.jpg

The thinner sectioned ribs are where the centre sheeting will be.

p1110275.jpg

Here is the complete rib set. I have gone away from the square leading edge set on the diagonal. I think Peter has moved away from this now. I prefer to use a false leading edge for building and fit the leading edge later. The thick end ribs will allow me to do some wing tip shaping if I want to.

Peter. I have tried but I am faiing to understand the tapered trebler in the left hand side of the nose. I am not sure what to do. I am thinking of putting the engine inverted and leaving the bottom of the cowl open. Is the taper anything to do with side thrust I which case I will build it into F1.

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All that tapered trebbler is for is to provide material to shape the nose the match the spinner The sides are straight so you would not be able to carve them down to the spinner size. The trebler makes the front thick enough to shape

NOTE. I never use side thrust. I get a swing on take off which I corect with rudder. In flight txhe model flies straight.

I have never seen a full size aircraft with side thrust. If they need anything like that they use an offset fin.

As a point of interest Yuppy Love was nice and fast and aerobatic on a PAW .15 cce engine. that is an 09.

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  • 3 weeks later...

Turning out to be reasonably quick build for me and a real pleasure. Decided on inverted in the end. The wings are covered and now working on the nose. Here are some points of interest along the way.

p1110302.jpg

Another small mod was to use wing bolts instead of rubber bands. This was partly due to keeping the number of servos down. I have outboard ailerons on the lower wing and these are driven with a link from the top ailerons. I thought it would be important for the wings to have a register and fixing so that the link dimensions will remain the same. Working on the assumption that all dimensions will change drastically in a proper crash.

The block supports the wing bolt and is glued securely onto the top and bottom spars. The black cord is braided spectra (fishing line variety) It is very strong, very stable, extremely light. The plan has no shear webs between the spars and although the wingspan is quite small there was quite a bit of deflection and with the front section sheeted this induced a noticeable twist. Again I wanted the relationship between the wings to stay constant for the linkages. I know that the covering stiffens everything up but I wanted to do a little experiment. See next photo.

p1110414.jpg

The thread sits in a very shallow knife cut in the ribs where they meet the sheeting. Just enough to make sure the thread is deep enough not to get rubbed out when doing the final sanding. The thread is pulled just taught and cyanoed into the slot, where it lies along the spars and at the intersections. The result was really noticeable and I am certainly going to try it again on a thermal type glider or similar. It was very easy to do and much quicker than fitting webs.

This is the underside of the top wing with the torques rods for the strip ailerons.

p1110416.jpg

This is the top of the lower wing with the arrangement for the one piece flap that straddles the underside of the fuselage.

p1110418.jpg

This is the fabrication of the two main formers and the servo tray. It is self-jigging and just need the rake to be set up over the plan. I try and get as much of the fiddly bits done before putting the two halves together.

p1110412.jpg

Here is my favourite way of bringing side sheeting together with ensures getting it correct to the centreline (over offset if you want to). Two rigid pine beams are clamped to the parallel section of the fuselage. Dowels of a suitable diameter are rolled into the gap until the correct shape or dimension is reached. Two dowels can be used in tandem to spread the load and vary the curve. The arrangement is completely stable and the dowels are easily rolled in or out. Normally their position can be set by eye but for real precision they can be measured against a reference mark placed on the beams. Any former or firewall is easily dry fitted to get good matching tapers and when ready, the whole thing acts as a clamp. The method works just as well on fuselages that are tapered or if you want more clamping pressure on the top or bottom. Simply roll the top or bottom further in and there you have it. It is much quicker than jigging off a board and a doddle to use.

p1110419.jpg

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Progress a bit quicker than the blog work slowing things down a bit.

p1110437.jpg

Trial fit of the engine (inverted). There is not much room in there! The nose of the aircraft is not detachable, not in normal flight anyway. I did not have any dowels or round bits large enough to follow my own methods so made do with bits of balsa to squash the nose into shape.

p1110440.jpg

Here you can see there is just clearance on the engine mount after some removal of the nylon. The nose ring is epoxied into place. I use very little epoxy (mainly aliphatic and cyano) but here it is ideal because I can select the cure time I want and it works well bonding the end grain of the balsa onto the plywood.

On the sides you can see the 0.8 mm plywood doublers. In the early stages of the construction I only bonded them as far as the former at the front of the parallel section of the fuselage. Try to make these tight curves is very hard and builds in lots of unwanted stress. This was very easy to bend as the doubler just slips along the balsa. In this photo you can see a slight gap.

p1110445.jpg

Now is the time to lock the shape in. First I opened the gap slightly using flat toothpicks and then drizzled a small amount of medium cyano into the space. Quickly taking out the picks and clamping with clothes pegs has the job done in seconds. Minimal stress and effectively a very strong curved laminate.

p1110439.jpg

Here is another view of the engine fitting procedure. I am trying to make the engine removable once the model is fully complete. I think I might just do it with any luck. Here you can see the hole in the nose ring is a snug fit on the prop driver. That has given me the accurate position of the engine for drill the holes in the mounts and leaving a nice neat gap at the front for the spinner.

p1110444.jpg

The nose ring is then bored out to the biggest size I can reasonably get. This just allows me to get to the machine screws hold the mount to the fire-wall past the crankcase.

p1110448.jpg

The top sheeting is now glued in place and roughly shaped. This stabilises the whole front end and the hard part is over. Yuppy Love is starting to develop her very distinctive front.

p1110450.jpg

p1110451.jpg

The last two photos show the top and bottom wing seats along with the servo tray built between the two main formers. Fuel proofing is now in progress.

Next job to fit the tank and the plumbing. Peter warns this is a bit space challenged!

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Thank you Peter.

The top wing has strip ailerons

p1110530.jpg

And the bottom wing has outboard ailerons spanning the last two rib bays. The one piece flap runs right across the centre section of the wing. The chord of the lower ailerons and flap is 6mm more than on the top wing. I am hoping I have not killed the response.

Oops - I've given the colour away but the actual colour is much more lurid! After I had finished covering when I looked at something white ie WC it turned green in my peripheral vision.

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Oh Help!

It's lovely I want one.

1. Its balsa.

2. Its a biplane.

3. Its cute.

4. It looks like it would be great fun to fly.

5. I have a suitable engine

So many models so little time. Sigh, I think I need therapy. But building is therapeutic..... But first I must finish the Spacewalker and what about the .. and the.. and the ....... oh yes once I was building a Sparrowhawk...

It really is cute. Help!

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You won't regret it Charles. It is very very endearing.

Looks like I forgot to show a picture of the bottom wing.

p1110529.jpg

With the outboard ailerons controlled by links from the top wing ailerons. The one piece central flap is controlled by a servo concealed in the fuselage on the top surface of the wing. The linkages for the flap are internal so it is very clean.

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