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Precedent Stampe 1/4 Scale


cymaz

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So here is a question about aligning the top wing.

After mounting the cabanes and the top plates earlier in the build I noted that they were a bit out of alignment but figured I could deal with this later. Today I made up all the cross braces and also the additional braces going down to the top of the front turtle deck, as per full size and other models featured here, and then clamped up the top plates with a simple jig as per the photo. Today I soldered everything up and fitted the bolts down through the turtle deck. Once everything was set in place I released the jig and checked the top plates. Grrrr, not quite right!, as the top plates seemed to have some memory of their previous positions.

Now with the additional diagonals to the centre of the fus, things are super rigid and although I have yet to trial fit the top wing I reckon it s going to be a bit of a struggle. When I built my first Stampe I didn't bother with any additional cross bracing and this meant the top plates were flexible enough to give some leeway to any minor inaccuracies.

Back to my question...how have others managed with the super rigidity of the additional bracing? Is the flexibility of not having them a benefit? I am beginning to think the flexibility might be kinder to the airframe in a disorderly arrival with the ground.

b882872a-fcbc-4eb4-9b4d-4ae5c9fc5ecb.jpeg

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Regarding engines be careful if you fit a saito FG30. They run hotter than the pits of hell when cowled and the stampe cowling is less than stellar for airflow. Im not saying it wont work, just be careful.

If you opt for glow then 180 would be my choice as you can throw a nice big prop and just float about. You can also enter loops at scale speed and use the power to pull you round. With a smaller engine you have to gain excess speed and then throw it round the loop and that sort of ruins the look a bit.

The cross bracing struts on my model fail with alarming regularity and the wing gets a bit wobbly without them. I dont think it will fall off, but it can yaw quite a bit so i tend to replace them.

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I guess I was lucky, my cabane struts came out straight. I didn't line up the cross-bracing until I had lined up the bottom and top wings. Then I wrapped the cross-bracing to the struts with heavy copper wire and silver soldered it. even with all that I still have to resolder some of the joints occasionally.

I wish they made a big wheel collar with four lugs 2 clamp all the struts together instead of soldering

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There are various points of failure on mine but i think its because the grade of wire used was too brittle and bending it before soldering has not helped. I replaced some of the cross braces with softer wire and they are doing fine at the moment.

When i build another one of these i will bin this method of cabane strut and instead make struts that i can bolt on/off and have them adjustable to get incidences and things right. It might be more complicated in some respects but it will also save a bunch of hassle when it comes to rigging and covering

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f5d4ed39-a583-41cd-899b-2a8b1021869b.jpeg9b5a4e01-64b7-46c6-8298-333462fba22c.jpegThanks to all the UC posts on this thread I have almost completed my sprung version.4e8cea08-dbd1-4040-9e94-c2a4e4e8b3c8.jpeg I used 169mm oleos from Hobbyking (took an age for them to deliver) and as they were a tad long I removed 9mm from the piston rods. To make the connection to the alloy brackets I soldered a 5m bolt into a one of the screw holes in a brass 16amp connector and cut the head off and removed half of the connector. The fore strut was similarly dealt with but using a smaller brass connector bolted to the fus. Everything else made from the cut up original uc piano wire with brass tube ends. A bit of brass strip for the centre link and main leg brackets.

I haven’t forgotten the rear strut, which I will fit once I have finalised the wing seating.

not too far off the covering stage once the front end has been fuel proofed. Need to start thinking about rigging wires. I didn’t bother on my first stamp but guess they will improve the look no end. Any advice on what wire to use and where all the attachment points are.. I do have a reel of 100lb black plastic coated trace wire, which I bought for the rudder Closed loop... any good?

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Rather an impostor here, but just to say that sea fishing tackle shops are a good source of beefy pull pull wire, crimps, swivels (enable one end of aforesaid to be adjusted without kinking), small split rings to attach swivels to wire etc. Plastic coated 50 lb trace wire is strong enough to be confident, flexible enough to accommodate bends and to loop fairly tightly, and the plastic coating gives the crimps something to bite into without prejudicing the stranded wire core. It does however chafe if put through a tight exit radius.

BTC

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