Jump to content

Fouga magister 1/4.5 moulded from scratch


dirk tinck

Recommended Posts

Advert


Change of plans !

Instead of making the thrust tube plug the traditional way (foam and ply ) I asked our friend Andy Meade -3d print specialist-to print the tube and to use it as a plug. I'm very pleased he took on the challenge !!

This will sure speed things up ! this gives me the chance to start the next thing on the long list of things to do !

So , the canope it is !

The moulds for this 95 cm long canope made for the PSS fouga , sadly did no survive the first pull !The reason is that the gel coat i used in 2016 came loose from the mould...

20201124_212925.jpg

20201124_212938.jpg

Thank God the plug is still in perfect condition !

20201124_212911.jpg

This is the reason i don't use gelcoat anymore ! To much work is lost this way !

As it's not a complex shape , i'll have a new one in a week or so wink.

Are you joining ??

Let's go !

Link to comment
Share on other sites

Hi all !

The first step in the canope story is prepairing the plug to make the moulds. I decided to make it in four pieces : an upper and a bottom half. Both pieces are going to be split in the middle (lenghtwise)for easy demoulding.

I screwed a base to the bottom of the plug and made it follow the bottom curvature

20201127_232235.jpg

Added the marbels for a exact line-up. Six in total.

20201127_232251.jpg

At the back side , i need to place a wedge to make demoulding more simple. Without it , it would be impossible to remove the moulds .

20201127_232305.jpg

This little piece is going to covered with some epoxy to get a glossy surface.

I also prepaired the parting board to split the upper mould.

20201127_232549.jpg

The rest is for tomorrow !clockmoon

See you !!

Link to comment
Share on other sites

Not much building time as my tow-truck needed the radiator replaced !

Just fixated the upper parting board with epoxy and some scrap foam blocks. At the same time, I tryed some alternative to fill the gap this time . I covered the edge of the parting board with a fillet of car body filler , but mixed with a small amount of harder so that it cured much slower than normal. While slowly drying , i removed the filler that was sqeezed from between plug and parting board with a putty knife. Works fine !!The advantage here (relative to the plasticine method ) is that you don't push the plasticine deeper while waxing , so cleener edges on the mould !

20201128_225137.jpg

Ready to wax and PVA !!

Cheers , Dirk.

Link to comment
Share on other sites

That's looking good Andy !

This would take at least a few weeks to make it the traditional way ! Even then , getting the two sides identical , wich is crucial , would be very dificult !

Thank U very much for the effort !

Just a little note : The 14 mm dimention , that is the offset between the two diameters , right ?

Cheers , Dirk.

Link to comment
Share on other sites

Thanks a lot Andy , this is going to save me lots of time !

While the thrust tube is being printed som 500miles away from me , i made some progress on the canope .After the waxing and pva it's time for the first layer of the mould : the black moulding resin applied with a brush.

Second layer is 50gr cloth , then 100 gr and then 6 layers of 200gr. It's a very time consuming job and after the 4th layer of 200 gr it was way over midnight and called it a day .moon To get the following layer adhere to the last (wich will dry overnight )i sprinkled cloth snippers over the wet resin.

20201201_201346.jpg

20201201_220514.jpg

20201202_002738.jpg

The last two layers are a fact now and everything is left to dry overnight.

Tomorrow i can hopefully clean up the edges and remove the top parting board , clean up the other half and start waxing ! No time to waste !

Link to comment
Share on other sites

Hi peter , glad i cought your interest !

The epoxy cured well overnight so i could remove the overhang and clean up the edges with a disc grinder.

I carefully cutted between the new mould and the upper parting board , removing the last .No problems !

20201203_230926.jpg

This makes the other half ready to wax and to cover with pva .

20201203_230950.jpg

Another long night ahead !sad

Link to comment
Share on other sites

So, printing was progressing well, and with about 9 hours to go I get up in the morning to see this!

img_20201202_124744.jpg

Disaster! I thought maybe the filament had jammed or something else horrible. Turns out, the X carriage stepper motor wire had caught around the leg of the control box, then unplugged itself as the Z axis pulled it up. oops.

To the CAD machine, Batman!

img-20201202-wa0017.jpeg

A quick measure from the print bed told me how high the print had failed, so I cut the model and exported 2 noggins as shown above to fix the intake mould.

A quick print of two of those, stick on with thick cyano, rub some red spot in, sandy sandy sandy, and it's nearly ready.

img_20201204_125239.jpg

Link to comment
Share on other sites

Don't worry about the seam Andy ! The printed tube is only the plug , right . Once it is primered and painted , it will all be forgotten. Lucky you didn't have to print it all over !

It looks like the surface is much better than most prints i've seen ! Less work for me !

I'm overall impressed !!

Greetz , Dirk

Link to comment
Share on other sites

Posted by Bob Jennings 1 on 04/12/2020 09:09:05:

Great work Dirk, your shed time is amazing. Maintaining the drive to get it done is impressive.

Thanks Bob ! I DO feel blessed about my building possibilities like building time ,a nice warm shed , the tools , and a wife who let's me work on planes all these evenings !heart

Link to comment
Share on other sites

Hi all !

My last post ,the second half of the canope plug was ready to mould just up to the pva .

As you guy's know by now ,the following step is the black moulding resin applied with a brush. I forgot to take a picture but you all seen that more than once , right ? With the resin still sticky it was time for the first layer of glass cloth , however , first i fill the sharp corners with thickened resin (cotton flakes applied with a candy bag with the tip cut off )

20201205_195216.jpg

20201205_195221.jpg

Next is the first layer of 50gr glass and the second layer of 100gr

20201205_205415.jpg

the following 6 layers are 200 gr glass , all with a brush and spunge roller laminated.

20201206_204541.jpg

moonzzzzzzzzzzzz...

x

x

x

x

x

x

x

x

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...