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Martin's i.c. Tucano


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A lightweight twill weave cloth is glassed over the waxed cowl then a heavy twill cloth on top of this and left to harden.

Much hammering and cursing later you should have a female mould as shown in an earlier pic. This is cleaned, filled as required, sanded and very well waxed ready to put the gel coat and the cloth on the inside, which is what I am doing right now so fingers crossed.

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Back to covering. I did the rear end under the tail next just to make life easier. The main piece for one side is then cut well oversize and taped to the top.

First pic is just a size comparison of the two models. The next is how you trim around the canopy using a ruler taped on.

Trim to the hidden side of the ruler with a new blade. This edge can now be tacked on.

The film is now trimmed around the canopy rear edge and tacked with a cool iron. Sorry about the striplamp reflections.

The rest is tacked on then trimmed and sealed with a medium iron heat. The firewall and wingseat parts are pulled round, slitting if required. The piece around the fairing needs to be cut as you gradually peel back the main side piece. Seal all the edges using higher heat then work towards the centre to avoid air bubbles. The film must adhere to the balsa-not a smooth shiny surface so whatever you do, do not try to use a heatgun.

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Hi Martin,

Sorry it's happened - you haven't had much luck with this thread, have you?crook

I am unaware of any 'timeout' function - character limit, yes, but the site gives you an opportunity to trim the post without loss if you exceed it. I've often had a post open for an hour or more without a problem.

I've asked the other mods if they are aware of this and we'll let you know.. Personally, when I'm creating a longish post, having had a lot of work disappear into the ether in the past, I always now frequently copy and paste the text to a Notepad file in case anything goes wrong, such as the connection going down etc.

Pete

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The site does log you out if you don't do anything for a while. Unfortunately typing into the box to create a post is not "seen" by the website until you click the "Add Posting" button, but in the mean time your login might have expired.

As Pete says it is a good idea to write long / complex posts into Notepad first and then paste them into a forum post then you have a backup copy if something does go wrong and you get logged out.

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I don't want to spoil this thread with protracted admin discussions but having trawled previous posts on the issue of unwanted log-outs I can only offer the following points at present:

1. Ensure you have accepted cookies from this site. Cookie policy here

2. Tick the 'Remember me' option in the login box.

3. If you are, for whatever reason, using two PC's, you'll be logged out if you change from one PC to another.

4. This thread may provide some answers to support the above suggestions.

I remain logged-in for many hours a day (only 'cos I'm at home) and finding myself having been logged-out automatically occurs once in a very, very occasional blue moon. I hope your solution is somewhere above, Martin....smile

Pete

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Thanks again Pete, I shall look into the above tomorrow. I do find that if I hop from thread to thread then I have to log in again each time even though I always tick the `remember me` box. This just seems to be a recent thing as I never used to have any trouble with it. I cannot blame the PC because it happens on any I use, home or work.

Martin

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Right, I think we may be over the problems so let`s look at the wing covering, bit by bit.

The inside corners are covered first as before.

The film is cut well oversize for the first lower piece. The remainder of this sheet is best suited to the upper surface of the opposite panel-you will see what I mean.

It is tacked all round the edges starting at the root and tip then the rest.

All the edges are sliced through and pulled round using medium heat.

Don`t be too fussy here about straight edges.

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The tips are much more tricky. Use the high setting for your type of film and pull firmly round, a bit at a time until well over halfway. Trim off with a knife.

Seal all round with high heat. Do not shrink the surface until the complete wing is covered and do about one third of each panel top and bottom at a time to avoid warps.

The cowl is at last born and popped out of the mould easily for a change.

The flange is linished off and thin birch ply epoxied on where the fixings will be.

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An update. As usual lots of work done but not a lot to show for it.

The wing and fus have had the yellow trim added and the tail and fin strakes laminated from 1/16 med. balsa and cross grained 1/64 birch ply using Wykes PVA and ironed together. The covering was done and they were finally cut and chamfered to fit.

Some film was cut away for glueing.

Not quite as to scale at the rear end as I would have liked but it will have to do.

Couple more shots of the two side by side showing the cowl painted ready for clear fuel proof laquer.

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The tail trim is added. This took only about 25min.

The fus. roundels are made from film using a compass cutter and ironed on as for trim a circle at a time, positioning the red wirh a pin.

The wing seat was sealed against fuel and rain by taping plan protector to the wing then running a bead of silicone sealant on the seat. The wing was then bolted on and left to set overnight.

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Your trim and roundels look great.

You might have mentioned this earlier in your post but what covering film are you using?I ask because I was wondering if you are using any extra adhesive to fasten the layers of roundel to the fus. covering and if so what is it?

Thanks
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Hi Ian, The black and yellow are Solarfilm Polyester and the roundels from Profilm, which is also polyester based. No adhesive is necessary, just wipe over both sides of each piece with a tissue dampened with water to which a few drops of washing up liquid have been added. You do not need a wet surface with polyester, more to do with removing dust.

With the iron set to very cool iron on each piece starting at the centre and working outwards to remove any air. Troublesome little bubbles can be pricked out. Set the iron to medium and seal round all edges.

This does not apply to the cheaper polycarbonate type of film which needs to be applied wet to prevent premature adhesion.

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Now comes the fun bit, getting the pull-pull and other linkages in.

The throttle arm is very close to the firewall and the snake just passes under the fuel tank.

The pre-made elevator carbon rod is fitted.

The rudder linkage is pull-pull from Teflon coated wire (control line wire) and commertial M2 ball links. The wire must pass through the brass tube three times and this can be crimped up when you are happy with it. Initially tension as much as possible since this will slacken later and and be adjusted. These can actually be quite slack when in use.

Ailerons and flaps next time.

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Very nearly there at last. Ailerons and flaps hooked up and the Tx programmed. Servo slow is employed on the flaps. A mock up assembly is done, really just awaiting some cowl fixings.

A CG check was done, and even with the battery as far back as possible that long nose made it about three feet too nose heavy so lots of church roof will be required in the tail. All up weight without that is a miserly 6lbs 13oz (3.1kg) so the 63 it will be test flown with will be rather more than enough.

Some pics, the shed debris and all.

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I have added some 5 1/2oz of lead to the tail.

The hatch was then filmed over.

This still only brings the cg to a point forward of where I think it should be but will be a safe starting place.

The choice of motor for test flying has been changed to a YS63S which should just about propel it into earth orbit.

Everything checked over and the only excuse now is the weather again.

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