62.5 Inch Tony Nijhuis Spitfire Build Log.

[GrahamC]

Hi Edward. The rib sections on this build would be missing the leading edge, and you would have to guess, so not very helpful I'm afraid.

 

A quick Google found this though, which might be more helpful.

 

Just a few minutes fiddling with the retracts to check the position of the bearers. I'm fairly happy with the results. See what you think.

 

 

[Edward smith 2]

Guessing on the leading edge wouldn't be so bad, I have a pretty good idea of what it should look like, it's the twist in the wings that is confusing me so much.

[GrahamC]

Right. Today I've glued in the retract bearers and fitted the plate for the wing bolts. Just the flaps to sort out before I cover the bottom of the wing.

I thought I ought to beef up the joint between the plates and the ribs, so I cut these fillets from scrap ply. The plans specified 4mm poly for the plate, but there only seems to be 3mm in the wood kit. I decided to beef up the front of the plate with some offcuts of spar

Having got both wings to this stage I couldn't resist popping it all together to see how it looked!

 

I made a card template for the flaps.

I'm now scratching my head and working out how to make a hinge. I think the servo's will go under the radiators. A few more pictures of where the flaps need to go.

 

 

 

[Myron Beaumont]

GrahamC

Just wondering what flap angle you're intending to achieve ie for TO and landing .I've watched loads of videos which show the real thing with the sort of angle you have in your pics for landing -about 75 to 80 degrees I guess .My kit shows no more than about 15 degrees .For TO no doubt . I'll alter my hinges "pointy things" to accomodate the extra movement if you think more than 15 degrees would be useful for landing,otherwise I would use mylar jobs .

Myron YO 13 -Gets more complicated dept..

[GrahamC]

I'm certainly hoping to be able to get them down past 45 degrees. It's part of the look isn't it? A Spitfire on finals with the wheels and flaps down.

 

I've no idea as to what effect various anglesmight have on flying characterisitics. It might be worth starting a thread?

 

Anyway here is my sketch of the most promising idea that I have had so far. I plan to use 3 SLEC hinges that I have in stock per flap. I will fit spruce flap bearers between the wing ribs and notch them ready for a hinge to fit between the bearer and the wing skin.

 

I will then pin through the skin and flap into the respective substrate. I think I would pin between glassing and painting, so the pin would become almost invisible.

 

The flap servos will go in the wing under the radiators.

 

I certainly works in my head. I'm away this week, so I'll have a go when I get back. Hope you are happy with your servos. You don't hang around do you!

 

[GrahamC]

Having been away for half term, it's nice to get back to the build. Monday is my day off, and it wasn't really flying weather so the shed beckoned!

I've been giving some thought to the covering of the wings. I'm planning to use light glass cloth (25g) and Eze-Kote on the wings. Eze-Kote is a WBPU type product sold by Delux Materials and seems similar to Poly-C.

I've read horror stories on forums of warping when using water based products on sheeted wings. The instructions for the Eze-Kote say nothing about using a sanding sealer, and just recommend applying a thin coat to the substrate, followed by a light sanding before applying the cloth and brushing the resin through the cloth.

I decided to build a quick test piece from scrap balsa so see what happened if I did not use a sanding sealer.

Well here is the test piece. I have applied one coat lightly as per the instructions, and it has dried without warping. I'm planning to glass the test piece and see how it goes. Having never applied glass before, it will serve as a practice piece.

I have purchased a tin of sanding sealer anyway, and will probably seal the wings before covering.

[GrahamC]

The next job was to tackle the flaps. I used 2mm Ply and balsa framing in accordance with the sketch in a previous post. Here is the first flap completed.

And here is a close up of the hinge. The balsa held in place with a clamp is just a piece of scrap. Eventually the hinges will pass between the flap spar and the lower wing sheeting. I dropped a 5mm spruce spar into the ribs and rebated it to take the hinges as per the sketch in the previous post.

Here is the flap open. It will need a little fiddling once the wing is completed to open and close smoothly, but I am hopeful that the system should work.

Sorting out and dry fitting the first flap took a good couple of hours and the second one took about twenty minutes!

I have fitted servo rails for the flap servo which will be hidden under the radiator.

Finally I fitted paper tubes for the servo leads, and took a reference photo in case I need to do anything to the wing once it is sheeted.

 

I’ve noticed that there is a product for sale on ebay which seems to be aimed at the RC car builders. Its 1.6mm thick fibre glass sheet. I’ve read about something similar on Danny Fenton’s Spitfire build log. [I think it may have been called Pro-Skin] The stuff on ebay is available quite cheaply in fairly small quantities. I may give it a go next time I build flaps as it would be light an resistant to warping.

[GrahamC]

I chose to sheet the wing one sheet at a time. I did this partly becasue I don't have anywhere big enough and clear to glue the sheets together. I have read horror stories about wings warping after being covered and having fitted individual sheets, can understand why. Especially on the top of the wing, the taper and curve mean that I had to do quite a bit of work with a sanding block to get the sheets to butt neatly together.

Anyway, the bottom sheet going on. It took quite a while to mark and cut all the apertures on the bottom of the wing.

Anyway I had to try those flaps now the sheeting is on. Its looks like they should work quite well.

The wing covered and ready for the leading edge. It is such a thing of beauty, it almost seems like a shame to cover it!

Just about everything heavy going spare in the shed being used to hold the leading edge down! From right to left... clamp, grind stone, box of allen keys, box of spanners, box of screwdriver bits, solder, monster elastic bands and.... the bit of apron that fell off... with a sanding block to protect the trailing edge and a clamp to stop them sliding off!

The ailerons were marked as I covered the wing. It was still a relief to cut them out and find the cuts were spot on!

I'm currently working on what I think is my least favourite job during a build. I'm shaping the leading edges and wing tips. I've started with the razor plane, but am now working with the perma grit block. Even cleaning up every few minutes with the cheap vacuum cleaner I have there is still too much dust and it just seems to take for ever. Anyone got any tips for getting this right?

[GrahamC]

Well the wing is now covered with glass. I have to say having looked forwards to this part of the build with some degree of trepidation, having never attempted to use this method of finishing before.

I treated the wing to a good coat of JP Sanding sealer, to stop the balsa from soaking up the moisture and then covered the wing with 25g cloth and Eze-Kote finishing resin. This looks and smells like a polyurethane product similar to Poly-c.

Not that much to see by way of photographs but...

The cloth going on to the top of the wing. A good tip from a fellow club member (Thanks Richard!) was to use pegs or clips just to weight down the overhang and hellp it to stay tidy.

I glassed over the apertures on the bottom of the wing. It was easy to trim them back out again with a scalpel when the Exe-Kote had dried.

 

Another club member rang up as I was covering the first bit and said - try using a roller. Now Richard had mentioned this so I did have a cheap 4inch roller to hand. Having brushed the resin through the weave I used the roller to eaven up the first coat and lift off the excess. I was delighted with the finish. A second coat for the top of the wing is drying even as I speak.

 

Its always good to learn new techniques. I had been nervous about glassing, which seemed like a dark art! Now I'm wondering what I was worried about! It was a lot easier than covering with shrink film!

[Hugh Coleman]

That wing looks lovely Graham. Very neat job indeed.

 

As well as using the roller, you can also use a Spackle scraper to get rid of the excess resin.

And if you add micro balloons to the resin for a finish coat, you will have very little sanding to do to smooth it all out.

 

Hugh

[GrahamC]

Time to get up to date with the build.

 

Ailerons ready to sand to shape. I had thught about using Danny Fenton's technique of rounding and then using 1/64 ply strips to hide the hinge line, but I nealy fell over at the price of a sheet o ply in the model shop!

 

Shaping with sanding block

Hinge slots cut and ready to be covered with glass cloth

The wing is now sat upstairs in the house while I carry on with the fuselage. One of the flaps has taken on a shape I didn't want, and may have to be re-made.

 

This ASP 61 turned up with the postman, so Its time to have a go at the cowl'

 

Don't worry the right thrust is no-where near as severe as it looks in the photo!

The front ring of the cowl help in place with some spacers

 

By this stage I was getting frustrated! I've actually found this the hardest bit of the build so far. I made a 2mm ply plate, and am hoping that the cowl will be removeable and tidy...

After much head scratching it is getting closer....

 

Holes and gaps in the cowl can be filled, but the line between the cowl and the fuselage is critical....

 

 

I'm waiting for the glue to dry now before I attempt any further shaping. I can get to the four bolts through the nose ring. It won't be easy to remove at the field, but I'm currently planning to make the bottom of the cowl seperately removeable.

 

The side thrust may make getting a symetrical look to the fuselage tricky, but I have told myself that If I am not happy with the results this time, it doesn't represent too much of an investment in materials, and I can have another go.

 

 

[GrahamC]

And... I need to make some decisions about the scheme that I am going for. I'd like silver. It's a bit different to the many green and brown schemes, and I quite fancy attempting the Mark IX of the battle of Britain Memorial flight. MK356.

 

I wish this aircraft had invasion stripes! That would make orientation so much easier!

 

The reason for the urdency of decision is that I need to get on with the tail feathers next and MK356 has a pointed rudder.

Anyone know of any silver RAF Mk IX schemes with invasion stripes? I've had a look on Google, but not seen anything yet.

[Photo is creative commons and some rights reserved by Sandchem at Flickr]

[GrahamC]

Hmm... Seems to be problems with posting! I'll have another go!

 

Well I finally have somthing that looks like a cowl. Just plastered on some filler in an attempt to tidy around the front ring.

 

I've changed my thoughts about a scheme. A club member suggested a PR Spitfire, so I had a look and came up with G-MKXI

I think its a little different to the normal Mark IX. I won't have to fit canon barrels or bulges. The caowl is a little more bulbous, but it just so happens that...

So is mine!

She does have a pointy tail, but that is drying as I type.

 

I've decided to go for a compromise between plan and scale on the horizontal stabiliser, and I'm happy with how it looks so far.

 

So now I'm waiting for the canopy to arrive before I finish sanding and shaping the fuselage. Paypal says I've paid for it, but when I rang today the helpful lady in the myhobbyshop office told me that their computer didn't think I had.She was going to try and sort it out for me.

 

I can get on with covering the tail. I'm planning on grabbing some tissue from my LMS and using that with the EZE-Kote in an attempt to keep the weight down. I must try and remember to weigh the pieces before and after!

 

[Stephen Grigg]

Very impressive build to congratulations so far

[GrahamC]

Thakyou Stephen for your kind comments...

 

I think it must be time for an update on the build.

 

I decided to try and keep the weight of the tail down by covering the tail surfaces in tissue and Easy-Kote. I've used WBPU and tissue on foam before, and didn't see any reason not to try it on balsa. (And I didn't fancy the smell of dope!)

 

Anyway I thought it would be interesting to weigh the components before and after the covering. Here is before... 52g (sorry for the fuzzy photo)

 

And here is after tissue, three coats of varnish, and a coat of undercoat.

 

66g. Probably more than I expected, but I suspect lighter than I would achieve with Solar film .

 

I spent a while scratching my head over the tail before realising that one of the pieces in the wood pack is simply the wrong shape! The front of the fin is just too small. I have to say that this is the only piece that seems to be wrong to date. (And there is nothing else left to use!)

I decided to make some cutouts from scrap depron to help me get the fuselage shaping right. Appologies to those for whom this is obvious, but I thought I would show you how I cut pieces to shape.

 

I pop the plan in my printer scanner and make a copy of the pieces I need on some scrap paper. I then tape the paper on top of my material, and simply cut straight through the paper template and material in one go. A lot easier than pricking out! Technology is wonderful. (When it works!)

 

Ready to cut

Then I used the cut outs to judge where material needed to be removed.There is still quite a bit of material to be removed here in order to get the green marks down level with their respective balsa laminations.

 

A quick scribbble with a sharpie shows where material needs to be removed.

 

 

Back in a moment...

 

Edited By GrahamC on 06/12/2011 21:47:39

[GrahamC]

The other job I a tackled on Monday, was fitting the cowl around my engine. The first job was to take a hole saw to my lovely cowl. I have to confess to a few last minute doubts along the lines of "maybe it shuld be electric" but some of you will be gald to know that I told myself that it wouldn't be right and pressed on with the drill!

 

No turning back now! I don't have a great deal of building expereince, but I have learned to allow plenty of time for cowls!

 

This picture shows the "I think I'm nearly there, but actually if you are going to be able to get the cowl on and off with the engine in place and then fit the silencer you have loads more to do" stage!

 

I decided to take advantage of a little sun to reward myself and put the whole project together to see how it looks.

 

Starting to look the part isn't she? Encouragement to pres on indeed.

 

Finally, Iv started to cover the fin and rudder in the same way as the elevator and horizontal stabiliser.

 

 

Best technique so far, is to brush the Eze-Kote through the tissue working quickly, then lift the tissue back off and using a finger and more varnish as neccessary work from one side and rub the tissue down onto the balsa to try and avoid wrinkles. Any wrinkes left can be sanded away when the Eze-Kote sets. I might do a quick video in a moment!

[GrahamC]

An update on the progress of the build. During the week, I tried to beef up the rocker box covers on the cowl. I'm not happy with the result, and may yet take the Perma-Grit to it and take most of it off!

 

Anyway, Monday is my main building day, and I fitted the wing dowl, and the wing mounting plate and decided to make a start on the wing faring.

 

First job, was to cover the wing in cling film and fit it to the fuselage.

 

Next I drew the line of the faring onto the wing and made a paper template for the plywood base of the faring.

The flight box was an ebay bargain. £1 for the box and £2 for the bolts to fit the model restraining arms!

 

 

 

[GrahamC]

I decided that getting the ply between the fuselage and the wing was going to pose problems, and that as the wing was a very good fit, the ply base should be fitted to the fusleage with a balsa fillet and foaming polyurethane glue.

I've never done this before!, I thought a few formers might be a good idea, and I've seen them on other build logs, so I added them.

 

The bases of both fillets done. Now the fun starts!

I've discovered that roling the 1/16th balsa tops of the fillets is going to be problematic! I got close having soaked the balsa in a fish kettle! But not close enough. (It even has a metal bit to hold the bits of balsa under water!)

 

The latest plan is to soak two laminations of 1/32 balsa and laminate them into position with watery PVA. I don't know if it will work, but it seems worth a try. I seem to remember reading somewhere on this forum that you could use cardboard. I have experimented with the EXE-Kote on card, and think that if I can't get the basla to bend enough that might be the way to go. When the glass cloth has been applied, I reckon it will be pretty stiff.

 

Sat on the ebay flight box.

 

[Myron Beaumont]

Should have bought the TopFlite Spit kit! Pricey but all the bits are there for perfect wing fillets.Thin ply and ABS plastic preformed mouldings

[GrahamC]

You might be right Myron! However the kit and plan were a real bargain. The whole lot only cost ?35, and I've enjoyed it and learned a lot.

Has your TF spitfire flown yet?

I do fancy a Top Flight Sea Fury at some point. I'm not sure that will be next though. I actually have a kit for a Royal /Marutaka Zero that someone gave me to build, and I think I might tackle that next. I have heard there is a lot of sanding involved in one of those too!

[Myron Beaumont]

Graham

Cost 'er indoors a lot more than that ! No its not flown .in fact I havn't worked on it since making the tail feathers & it is a Xmas pressy after all .I have lost enthusiasm for it and have been drawn to making a nice simple vintage type model recently thanks to the coverage in RCM&E recently (and a couple of scratch builds as well since I'm trying to use up my balsa stock before it goes off )

[GrahamC]

Finally the wing fillets are done, and sanded, and the fuselage is ready for the glass cloth. I found some 18g cloth on ebay and managed to lay it over the top of the fuselage in one piece!

 

I have been banished to the other corner of the shed as my Son has begun putting his Renegade together on my bench! He has no servos yet but hopes that might change come Sunday (Christmas Day!) He knows he has a nice used ASP 61FS coming. We just have to decide whether to fit it at angle as per the engine mount or attempt the fiddly process of mounting it upside down and getting new captive bolts on to the fire wall. Hmm!

 

Bottom of the fuselage showing the last piece of cloth going on.

I put the model together yesterday evening and checked the incedance of the wing and tail plane. I have +2Degrees on the man wing at the root with about .5 Degree of washout by the tip. and 0 Degrees on the tail which looks to be about right with the plan.

 

 

 

[Vecchio Austriaco]

nice building thread Graham! I am looking forward to see how you will proceed.

All the best VA

[Firstflight]

Yes, very nice build!

 

How have you solved the linkage to the elevator?

 

On my spit I`m trying to make a internal linkage (like Denny Fenton did) but my lack of silver soldering skills makes me looking for other solutions.

 

You can see my building thread here: http://www.svensktmodellflyg.se

/Mattias

[Phil 9]

nice build Firstflight no CNC packs for you