Fouga magister 1/4.5 moulded from scratch

[dirk tinck]

Hi guys...and.....ladies !

 

With the main gear in the right position and the wings in place it's time to mesure the nose height. If you look at the real fouga's you'll see that they ''sit''on their nose quite a lot ! That means that i need a much shorter nose leg than the one i have...You could say that's an easy fix by placing the retract higher but then the gear door gets to big and the wheel goes to deep in the fuse.  I searched the net for a shorter leg but couldnt find a suitable one. My last chance for luck was the website of Mr. Philip Avonds (Avonds jets ) His business has ended production but...He ha just one nose strut left in stock !!😉 We agreed that i pay him a visit saturday to pick up the nose leg and nose wheel. They are real beauty's and 100% scale ! So is the price tag...🤑

 

My shop is getting way too small for this model !!

 

 

So , i have to wait for the nose leg , but there's no time to rest !!

I started to make the mould flanges for the nose gear door , a little bigger than needed but that's better than too small !!

 

 

 

Tomorrow the circus begins again !!

 

Stay tuned and good night !

[alan p]

Beginning to spread it's wings👍

[dirk tinck]

Hi all !

 

finished the mould for the nose gear door. This had to be done before i make the opening for the gear strut.

 

 

When the epoxy is hard , the mould can be removed from the fuse.

Next thing will be the fitting of the nose gear retract and its support.

Thanks for watching !

 

[McG 6969]

Heya Dirk,

 

If I may ask, what kind of grammage are you using for that mould ?

It looks like 100gr/m², but most importantly, how many layers are you using to get it right ?

 

Thanks in advance

 

Chris

[dirk tinck]

Hi Chris , all together i used around 800gr . The flanges make it strong so i think it will be enough. Time will tell !

[dirk tinck]

I used a few layers of 100gr and the rest was 200gr

[McG 6969]

Hi again Dirk,

 

I guess 800gr will be more than enough with those 'flanges'.

In fact it will not even be a very 'stressed' part to produce, will it ?

 

Thx for your fast answer

 

Chris

[Nigel Dell]

Dirk, I had been following this thread at the start then life got in the way and I hadn’t been on here much, now I have re aquatinted myself with your project I shall not stray again! You are a true master my friend, I am in awe of your skills.

[dirk tinck]

Thanks Nigel , glad you're back , the best part is yet to come !

 

Got the nose strut and nose wheel from Mr Avonds saturday , some piece of art !

 

 

I immydiately started to draw the formers and the retract tray on cardboard and copied them on poplar plywood (formers ) and aircraft ply (tray ).

After some fitting i came up with this :

 

 

 

 

 

 

I know the wood-nuts are upside down but it's temporary. (I dont want to weaken the retract tray with their pins )

After a dry fit , the next thing is open-up the fuse and check the height onder the nose when the plane is on its wheels (for the very first time !!)

Note the shape of the scale tire ! Just like the real stuff !!

[dirk tinck]

Find the differences 🧐

 

 

 

This is the kind of wheel and strut on the Avonds fouga that won JET WORLD MASTERS...Twice!! As did many others on other competitions.

[GrumpyGnome]

Your 'work of art' airframe deserves such a great undercarriage!

[dirk tinck]

Hi all !

 

After a fabuless pss weekend at the Orme , i'm back at work on the fouga. With the nose retract support ready to glue in i want to make the gear door first.

The nose gear door mould is free from the fuse and after a clean-up i waxed it six times and gave it a coat of pva mould release agent , followed by 50gr cloth , and 6 layers 100 gr cloth. In between i laminated some strings of carbon for strenght

Everything is hardened out and ready to fit on the fuse. First i opened up the opening in the fuse to the correct mesures so that the retract can move freely.

 

 

The new retract door

 

fitted in the right position , i can see through to mark the door outlines

 

 

I have to wait a day to cut out the door with the grinder because the epoxy would still melt with to much heat (not hard enough)

I gave it a shot to make the right door hinges from a aluminium T profile scrap

 

 

Because of the round shape of the gear door , the hinges must bring the door a little ''out'' of the fuse so the strut and wheel does not tuch the door when opened.

It's just a try-out so the shape can change during fitting.

More tomorrow !!

 

 

 

[Danny Fenton]

On 02/10/2020 at 19:48, dirk tinck said:

Hi, Alan P,

Sorry it was unclear,

The tube i made is nothing but glass cloth,glass-fiber.The one i used was 136gr m².

It's a very easy and effective way to make the tube for wing joiners or in my case now ,rudder -fuse joiners.

If you worry that the tube might be to big (inner diameter)for the joiner they are made on , because of the plastic in between , i can assure you ,that is NOT the case. It is still a perfect fit !! If you hold the combo vertical , the tube does NOT slide off !I just tryed it .The protective plastic is easy to pull out of the tube.

/sites/3/images/member_albums/149787/877394.jpg

If you want to try it , i recommend you look for a cloth tube close to the joiner diameter. You can stretch the tube but then the meshes get bigger

I purchase mine at the webshop of HP textiles , Schapen , Germany. Great service !!

/sites/3/images/member_albums/149787/877395.jpg

/sites/3/images/member_albums/149787/877396.jpg

Hope this helps ! If not , shoot !!

 

Hi Dirk, I know this is going back a little bit, but I have a 32mm OD carbon tube, and I need to make the outer glass sleeve as you have for a wing tube. I can only get 25mm or 50mm glass sleeving, so have a couple of meters of each coming, I presume I can either stretch the diameter of the 25mm a little? or stretch (length) of the 50mm to fit

 

Anyway about the plastic you used as a release layer, what sort of plastic, I was thinking cellophane?

 

Cheers

Danny

[dirk tinck]

Hi Danny,

 

I would try the 25mm sleeve and stretch it .Be carefull when you slide in the tube not to disturb the fibers. Maybe try to fit a ball in the tube for easy access in the sleeve.

 

Wax the tube a few times just in case some resin gets in between plastic and tube.

 

As for the plastic , i use the kind that florists use to wrap flowers , it's very thin but don't know the name ...

 

How long are the tubes you want ? If you need to make ,for example ,3pieces of 30 cm : don't try to make it in one piece of 90 cm !  The longer they are , the harder it is to wrap the plastic around the tube without wrinkels !

IMO the best way to wrap the plastic around the tube :  Calculate the circumference of the tube and prepare your plastic a little bigger (0.5cm) and 5cm longer on each side.

Make everything dustfree and lay the plastic on the table with the curls up.  Place the tube on the plastic , let it overlap and carefully tape (as small as pos ) the plastic without wrinkels . This is the hard part and if you're not happy , try again.

Turn the plastic at the ends and tape.

Place the tube into the sleeve and let it ''hang''.  I put a tie wrap around the end and add some weight to pull the sleeve for a good fit

 

Succes !! 

[Danny Fenton]

Thanks Dirk thats great, yes probably three sections of 250mm

I think the florist plastic is Cellophane, i have some funnily enough for laminating depron, makes it shiny 🙂

 

Cheers

Danny

[dirk tinck]

Hi again !

 

After 4 try's i got the shape of the door hinges right . I made a set of 2 , one with a hole for the actuator and one without . There is possibly some trimming needed but they will do for now.

 

 

I tried them out with a piece of door offcut to find out if the door lifts enough.

 

 

 

Good to go !!

 

Next i bolted them on a piece of 3mm rod because the hinges must be inline for smooth operation

 

 

Glued them on the gear door in the right position , taped the gear door onto the fuse in the right position , and glued the other side of the hinges onto the inside of the fuse. Then removed the rod and replaced the little M3 bolts with locknuts .

Job done !!

 

 

 

 

 

The hinges will be secured to the door and fuse later with tiny sunken screws. The holes are already drilled.

[dirk tinck]

I still have to make the servo mount for the door operation but need to order a little servo first...

 

Next task is the fitting of the rudders on the fuse.

 

Before i glued the fuse halves together i made templates of the different fuse formers wich come in handy now !! I taped a stick to the template to check the fit in the fuse.

 

 

Then copied the template onto 5mm birch ply . This will be dubbled up to take the stress of the rudders.

 

I glued 3 temporary blocks inside the fuse as a guide for the former.The rod in the double former is for easy fitting in the fuse...

 

 

 

???Two for the price of one ??

 

More later ! greetz , Dirk

[dirk tinck]

Hi again !

 

With the double former ready , its time to glue it in. To get it in the right place , i made a jig that holds the rudder/fuse joiners at axactly 110 deg. and perfect horizontal. I used it to test fit the rudders on the fuse plug so that should not give problems.

 

 

 

 

 

The former fits perfect but the openings for the tubes are a little off.  This is no problem as they are still to small to accept the rudder tubes.

These tubes are nessecary because the rudder former is to small to hold those big rudders (50cm).

Tomorrow i will make the tubes around the rudder joiner with cloth and epoxy

 

 

 

 

View from the front of the fuse. After curing i can clean up the former and remove the fitting blocks.

 

 

[dirk tinck]

Hi guys ,and girls...

 

I cleaned up the back part of the fuse and started to adjust the openings in the former for the rudder tubes

I can hear you thinking , why the extra tubes ? Wel ,as you can imagine , the former only gives me around 4.5 cm to support the rudders (50cm lenght) This would (IMO)never be strong enough...That's where the tubes come in ! I made a 20mm diameter tube around the carbon rudder joiner , 22cm long. Enough for L and R. The carbon rod is 14 mm diameter so the wall thickness is round 3mm . That should do the trick.

 

 

 

 

 

Dry fitted the tubes and checked the position in the jig before glue was applyd : All good !!  Then fitted the rudders and tail cone , i love it when a plan comes together !!

 

 

With the rudders in the right position  i made two aluminium braces to secure the rudders to the fuse former. nothing left to do than dril the holes and place  two wood-nuts in the former (inside the fuse )The braces are bolted to the rudders via the back side , for the moment with long bolts but they will be replaced by short ones , hidden in the rudders (allen screws )

 

 

 

[Danny Fenton]

I hadn't seen these pics until just now, and wish I had as it explains how you are putting tension on the glass sock.

 

I have just made wing tube sheaths and very pleased, put a couple of areas where the tube lifted a little.

 

 

 

I sprayed a release film over the carbon tube, then wrapped the cellophane around it. I wrapped it without any tape as I didn't want the tape to stick to the resin.

 

I used a 100g glass tube and West Systems Epoxy. It slid off with zero effort!

 

Thanks Dirk, brilliant, and don't be surprised if I include this in my column, of course I will give you credit.

 

Next ones I will try pulling the end of the tube while it sets.

 

Do you uses sellotape to attach the cellophane?

 

Cheers

Danny

Edited November 5, 2022 by Danny Fenton

[McG 6969]

Hi Danny,

 

Allow me to answer a few of your points.

 

I'm also making a wing tube for a self-designed high wing bushplane.

I'm using Dirk's method as well, but with an aluminium wing joiner tube instead of a carbon one as you have.

It is 22mm in diameter and I'm using a 'sock' of 30mm diameter. Mine is 300gr glassfibre with HP Textiles epoxy (same as Dirk).

 

In order to have the 'sock' following the tube closely over its length, I made my sock a few cm longer than the tube, then I bind it with a tie wrap under the tube end and add a 500gr weight to the underside. Mine is simply a 1/2 liter mineral water from Spa, but I guess the brand isn't of any strategic importance...  😉

 

The other side of the tube is just hanging from the workbench. Of course you have to work/apply the epoxy 'vertically', but that isn't a real problem.

 

Regarding the cellophane, I did the same as Dirk, i.e. taping it with a strip of Sellotape to keep it without wrinkles.

No probs as the epoxy will not stick to the Sellotape.

The main concern is to have the cellophane being able to 'slide' on its own after curing. Not sticking to the tube joiner nor sticking to the 'sock'.

When you slide the sock out, the cellophane will remain in the sock but can be extracted effortless.

 

Hope this helps a bit...

 

I wasn't aware that you were building another model after the Auster.

I could be wrong, but the fuselage fairings on your picture look a bit like those on the underside of a Chipmunk... ??? ...

 

Cheers

 

Chris

 

 

[Danny Fenton]

Hi Chris, thanks for filling in the gaps, I was tempted to use some sellotape to secure the cellophane, but static worked at holding it with no adhesive.

Another question, I was going to use Polyester resin but thought it might dissolve the cellophane, so stuck with epoxy. Any thoughts?

I liked doing all this horizontally, so will think of using a bungee chord to apply a pulling tension.

 

The video of the process is here

 

Yes I am building a quarter scale Chipmunk, this one is based on the Jerry Bates plan with lots of modifications, including increasing the dihedral. The build is on RCSB under "poor Man's Spitfire 2"

 

Thanks again Dirk for the inspiration

 

Cheers

Danny

[McG 6969]

Hi Danny,

 

Great if statics gave you a helping hand, but I don't have a great brand new roll of cellophane.

I have to use some second-hand one and taping a strip of Sellotape really helps...

 

Regarding the Polyester resin, it has been ages since I last used it due to fumes/smell.

It was NOT safe on most tapes but I don't know about cellophane? 

Having a test-piece would very probably give you the right answer.

 

Cheers

 

Chris

 

Edit > ... apologies to Dirk for clogging his Fouga build blog...

Edited November 5, 2022 by McG 6969

[dirk tinck]

Hi Danny,

 

glad it worked out well for you !

Dont be afraid to use clear tape , it won't stick to the epoxy and it's only some microns thick , just be sure the tape does not touch the joiner . As for polyester resin ,last time i used it is 30 years ago...

Note : Cut your sock a few inches too long on each side and grab the ends to stretch it.It will crimp nicely around the joiner.

Your tube looks good ! Glad i could help

Greetings , Dirk

[dirk tinck]

Hello again,

 

As you can see in the last pic , the rudder former holding the rudder tubes (glued in )got 3 layers of glass cloth (100gr)front and rear side. The front side was a real pain to do !!  With the fuse hanging upside down i had to look at the former trough the motor hatch. But when your head is inthere , it's not possible to bring your arm in the fuse with a 60cm long brush !! After trying some aerobatic manouvers for two hours i got the job done 😏

 

 

 

 

 

Next on the list of rudder-related things-to-do is open up the rudder skins to let the servo horns out ! No servo hatches here so the trick is to slide-in the servo with the horn flat lenghtwise . Once the servo is mounted , the servo has to be operated to bring the horn ''out'' in position . I drew the correct position on the rudders , drilled trough the skin and enlarged the opening with a file.

 

 

 

 

This ends the rudder chapter for now untill i have all the right bits like screws , servo couplers , etc... and i can fix all the details.

 

Almost forgot : the rudder hinges (robart)are also fixed !

 

On with the whistling hart of the beast ! The Schubeler 128 mm EDF ! What a fine piece of engineering !🤩