SHORT SOLENT MARK IV – 2014 WINTER BUILD

[wollins]

Nothing to report guys, this is just for my future reference. There's a honking torque rod inside each one now hence the relatively big increase in weight from the non covered weight. 

C.

[piker]

What?!  You're covering already?  You're not supposed to do that!  How will you get your pre-covering, finished construction, framed up photo?!

That's Sacrilege!

but it DOES look good   

[wollins]

What?!  You're covering already?  You're not supposed to do that!  How will you get your pre-covering, finished construction, framed up photo?!

That's Sacrilege!

but it DOES look good   

It's a habit I guess ... but in all seriousness, I had to do it cause since I'm now making the stabs permanent I have to glue them on in order to finish the sheeting on the tail portion (cause the sheeting merges with the stabs) and they'll be much harder to cover on the plane.


C

[wollins]

Well, I'm pleased to announce that I made some successful canopy pulls! Whoo hoo!  I am stoked about this cause it was a big learning curve for me since I had never done vacuum forming before.  Here's a couple of pics showing my first attempt way back in the build ... with the wrong tool, a heat gun. lol!

Colin

[piker]

So where is the final product?  Keeping us in suspense?

[wollins]

And here are my canopies with the right tool. A DIY vacuum former! I even have a "formula" for success now.  For anyone who has questions about the actual vacuum former itself I can share details no probs. Suffice to say its a unihole version (much less common than the perforated hole ones that people tend to make) which is MUCH simpler and as you can see just as effective.

Colin

[battlestu]

very nice!!

[Papa]

Way to go Colin. What dimensions did you use?


Jack.

[piker]

That is so cool.  I am SO gonna copy you!

[gmcnic]

Wonderful work, Colin!!  That's friggin' brilliant.
I can see it now, "Colin's Custom Canopies"

Graham

[wollins]

I can see it now, "Colin's Custom Canopies"
Graham

No, no, no!  I hope not to ever have to use my oven again for this purpose. I was really torn cause I really wasn't comfortable with the idea of potentially toxic (?) fumes in a place where my wife cooks! Anyway I really needed to get this done and was in a pinch so I decided to chance it. Maybe I'll rig up another heat source for the future.    

Anyways ... I've been asked for vacuum former "details" so I figured I'd post them here in case anyone else can benefit for the info.

"One hole" platen vs Perforated platen.

Went with the one hole version cause it's simple! Just a board with a hole in the middle. As opposed to a vacuum "box" covered with a platen, perforated with potentially hundreds of holes.

My platen/board was made of some MDF from Home depot and I lined its border with some 1/2" x 1/2" weather stripping from Home depot to create a seal between it and the plastic holder frame when the vacuum did its thing. I drilled my hole (to fit my vacuum's hose) in the middle of it with a hole saw.  Stuck my vacuum hose in there and it was a great tight fit. 

I then made my separate 1" wide frame (that holds the plastic) by cutting out the inside of another MDF board that was the exact same size as my platen.    To hold my plastic within the frame I just used my heavy duty stapler and stapled the plastic to the frame. You'll notice on one of the pics that I markered a border on the frame ... this represents where the seal (weather stripping) from the platen would contact the frame. I did this so that I would know where to put my staples ... I stapled inside that area so that the staples wouldn't contact the seal of the platen when they are pressed together. 

Using the stapler just happened to have another benefit.  The MDF was so dense that the staples would only go in halfway. However this turned out to be a benefit cause when it was time to remove the plastic it was very easy to just pop off the staples with a screwdriver!

I also used some metal shelving "L" brackets as "guides" for my frame so that in the rush of putting the frame with the hot plastic onto the platen these guides ensure that I get them to fit exactly together to get a proper seal. That's it as far as construction of the vacuum former is concerned.  Very simple.

As far as sizing is concerned I calculated that I needed a piece of plastic about 9.5" x 11" for my 4.5x6x2.5" plug.  I then added an inch extra (for stapling to my frame) so the actual plastic needed was 10.5" x 12", however I ended up with my platen being 15x12.

Another thing that I thought was a big factor in a successful pull was the fact that I raised my plug up on 2cm standoffs (drywall screws! lol) so that it was standing over the hole as opposed to sitting on top of the hole.  Obviously if it were sitting directly on the hole that would create a seal and the plastic would not be pulled.

However some people put a mesh screen over the hole and then the plug sits on top of that.  What this does is (apparently) create a more even pull by diffusing the suction.  However I wanted mine so tight that it would tuck under ... hence my standoffs. This allowed the plastic to not only be tightly pulled but tucked under the plug.  I couldn't get a tighter pull than that!

As far as the actually heating of the plastic. I put my frame sitting on two pieces of 2x4 lumber as a "stand", about six inches under the broiler. (which is at the top of ovens) I had my platen hooked up to my vacuum next to the oven.  I preheated the oven on "Hi" (my oven does not go by degrees in broil mode so I don't even know what temp "hi" is!) for 2.5 minutes.  I then turned on my vacuum (I knew things would potentially happen fast once I popped the frame in!) popped the frame onto my "stand" in the oven and it then took another 1.25 minutes to droop to my desired 2 to 3 inches. I then whipped it out and onto the platen and wham, it was pretty much done in a second of so!

That's it!

Colin

[wollins]

Employed Mya to prepare the "passengers" and boy what a good job she did!   The first four guys are going to a "Beats" Electronics  sales convention (notice the headphones!  ) but frankly I don't know where the heck the lumberjack is headed! lol!

Colin   

[sihinch]

That's fabulous! I need 1/7 WW1 pilot, can Maya help with that?

[wollins]

That's fabulous! I need 1/7 WW1 pilot, can Maya help with that?

She charges by the hour.    

BTW, I forgot a few shots. First one is of the elevator setup I finally settled on ... simple torque rods short coupled to a servo. Simple but proven and effective ... downside? H Stabs are now not removable.  Real tight back there so it was a royal PITA to get everything set up just so.

I even forgot to make an adjustment to the servo before I glued it in (its permanent!) and had to go through the top of the fuse with a homemade screwdriver to get to the servo arm screw! (second pic) Third pic you can just see the end of the "screwdriver" doing its job.

Last two was just before I started working on the nose.

Colin

[Papa]

Hi Colin, here's a wrench that may help.


http://www.lowes.ca/hand-tool-sets/kobalt-35-piece-standardmetric-right-angle-driver-set_g1185051.html?ProductSlot=5


Jack.