Beyond The Sprues

Current and Finished Projects => Physical Models => Aero-space => Topic started by: Tophe on January 13, 2018, 11:14:29 PM

Title: MiG-3Y Utka
Post by: Tophe on January 13, 2018, 11:14:29 PM
I got from Unicraft a Mig-3 model, that I plan to build in a canard layout (YTKA in Russian, pronounced Utka). ;)
I thought it was a Novo injection kit but it is a vacform... ???
Title: Re: MiG-3Y Utka
Post by: Tophe on January 13, 2018, 11:16:34 PM
Here is the project, but what glue to use? how cutting, how holding? solid?
Title: Re: MiG-3Y Utka
Post by: Frank3k on January 14, 2018, 04:28:14 AM
Tophe, vacuforms are usually made from styrene or (less likely) ABS so your average model glue will work. Clear parts for vauform kits are usually made of Buterate; you can us PVA  (polyvinyl acetate) to hold it in place.

Here's a good primer (there is no part 2): http://www.clubhyper.com/reference/vacformbg_1.htm (http://www.clubhyper.com/reference/vacformbg_1.htm)

 
Title: Re: MiG-3Y Utka
Post by: Tophe on January 14, 2018, 12:50:45 PM
Thanks a lot for these directions, very helpful! :smiley:
Title: Re: MiG-3Y Utka
Post by: Tophe on January 14, 2018, 05:14:36 PM
Of course I may imagine a Zwilling version, I may draw it, but I will not build it.
Title: Re: MiG-3Y Utka
Post by: Tophe on January 14, 2018, 07:30:59 PM
I have started separating parts. I love the presence of 4 (half) tailplanes. As I am never building a perfect model for every side including from below, just acceptable on some photographs from precise angles, I consider this model will have 2 set of tailplanes: foreplanes and T-tail planes.
Title: Re: MiG-3Y Utka
Post by: Tophe on January 14, 2018, 10:49:47 PM
I consider this model will have 2 set of tailplanes: foreplanes and T-tail planes.
Like this (and I think I will not use the fragile propeller):
Title: Re: MiG-3Y Utka
Post by: Brian da Basher on January 15, 2018, 02:32:36 AM
I really like that last concept, mon ami!

I can imagine it in WW II 1940 Armée de l'Air camouflage.

Frank has given you some rock-solid advice on glues. One thing I usually do with vacforms is insert a bit of sprue running through the fuselage wing root to hold the wings on. This will give you a stronger attachment than just butt joining them.

Best of luck and I know I'll enjoy watching this one come together!

Brian da Basher
Title: Re: MiG-3Y Utka
Post by: elmayerle on January 15, 2018, 01:24:51 PM
Going for a second-stage experimental to follow the MiG-8?
Title: Re: MiG-3Y Utka
Post by: Tophe on January 15, 2018, 11:38:54 PM
Yes, maybe this is the Historical/technical explanation (in our dreams) ;)
Title: Re: MiG-3Y Utka
Post by: Tophe on January 20, 2018, 06:09:50 PM
Even cutting the parts separate is not easy... The best tool I have found is scissors...
Title: Re: MiG-3Y Utka
Post by: ericr on January 20, 2018, 08:55:38 PM

vacform is not easy, but with patience you can do it  ;)
Title: Re: MiG-3Y Utka
Post by: Frank3k on January 21, 2018, 02:00:22 AM
If you can build - and finish a Unicraft kit, then a vacuform should be easy. Just think of it as a plastic model with far too much flash on the parts.
Title: Re: MiG-3Y Utka
Post by: Tophe on January 21, 2018, 11:06:15 AM
(With my poor standards in quality) I love Unicraft kits, yes I do.
Simply, vacform seems a new learning for me and I fear I may fail, I will see.

One of my major failures in the past was the handling of thermoformed clear canopies, and I keep that strongly in my mind. Even if the white thermorformed parts here may be a success at last, I will not use the thermoformed canopy of the MiG-3, just painting black the "canopy", and this is a reason to invent further, like this:
Title: Re: MiG-3Y Utka
Post by: Tophe on February 01, 2018, 02:40:46 AM
One thing I usually do with vacforms is insert a bit of sprue running through the fuselage wing root to hold the wings on. This will give you a stronger attachment than just butt joining them.
Do you mean a vacform model is intermediate between an injected plastic model and a paper model?
Title: Re: MiG-3Y Utka
Post by: Tophe on February 03, 2018, 05:24:23 PM
The parts are now separated/cut, ready to build, but I fear this will not be easy, maybe with adhesive tape holding parts during glue drying?
Title: Re: MiG-3Y Utka
Post by: Tophe on February 03, 2018, 11:07:45 PM
My adhesive tape try is not very good but it shows the project:
Title: Re: MiG-3Y Utka
Post by: perttime on February 04, 2018, 12:15:02 AM
I recall some articles mention reinforcing fuselage and/or wings. I've been wondering if polyurethane glue and water can be used to fill a vacform component.... I think it takes just a little water to start it foaming.
https://www.youtube.com/watch?v=QOB87l-r6Io (https://www.youtube.com/watch?v=QOB87l-r6Io)
Title: Re: MiG-3Y Utka
Post by: Tophe on February 04, 2018, 05:08:12 PM
I have not this product. I just started to glue, holding it with tape while drying, solidifying... (I hope):
Title: Re: MiG-3Y Utka
Post by: Brian da Basher on February 06, 2018, 10:52:47 PM
One thing I usually do with vacforms is insert a bit of sprue running through the fuselage wing root to hold the wings on. This will give you a stronger attachment than just butt joining them.
Do you mean a vacform model is intermediate between an injected plastic model and a paper model?

I'm sorry I missed this, Tophe. I've been ill with flu which is less fun than PSR.

I didn't mean to suggest that but now that you mention it, one could think of vacforms as intermediate in structural strength when compared to paper and plastic models. Whether or not you want to reinforce the wing joint might depend on the plastic. I've had some vacs where the sheet was so thick it didn't need any reinforcement. I often use scissors myself on these kinds of kits. The ones from the former Eastern Bloc countries are especially tough.

I really like where you're going with this model and I think you will soon have us delighting in your latest marvel, mon ami!

Brian da Basher
Title: Re: MiG-3Y Utka
Post by: Tophe on February 07, 2018, 12:57:35 AM
Thanks for these details!
I have used your sprues recipe, thanks for that too!
And I have put a thin layer of putty, not to dissolve the fragile plastic. There will be more and more later. :smiley:
Good recovery from the flue, Brian.
Title: Re: MiG-3Y Utka
Post by: Tophe on February 08, 2018, 02:34:47 AM
And, as well, a first little layer of putty on the underside, reinforcing the spars:
Title: Re: MiG-3Y Utka
Post by: Tophe on February 10, 2018, 07:07:09 PM
The silhouette is more attractive with the spinner glued in place. I will have putty work to operate there also.
Title: Re: MiG-3Y Utka
Post by: Tophe on February 11, 2018, 06:41:36 PM
4 half wings will be biplane or tandem wings
Title: Re: MiG-3Y Utka
Post by: Brian da Basher on February 12, 2018, 04:00:48 AM
That's coming along quite nicely, mon ami!

You have some serious vac skills!

Glad I could help a little, Tophe.

Brian da Basher
Title: Re: MiG-3Y Utka
Post by: Tophe on February 25, 2018, 01:29:35 PM
Thanks again.

Well, I went on a little, sanding the propeller basis bulbs on the spinner, alas that produced holes (see below, left), thus more and more putty (below, right):
Title: Re: MiG-3Y Utka
Post by: Tophe on March 02, 2018, 01:07:51 AM
After the first sanding, it takes shape, but lot remains to be done...
(http://www.kristofmeunier.fr/011-mig3-sanfing1.jpg)
Title: Re: MiG-3Y Utka
Post by: Tophe on March 11, 2018, 01:53:10 AM
Now that the paint work of the other model (Gee-Bee Zwilling) is finished, I have been authorised (by myself) to continue the sanding of the MiG-3, then starting to glue the lifting areas...
Title: Re: MiG-3Y Utka
Post by: Brian da Basher on March 11, 2018, 02:41:59 AM
It looks like you're having a wonderfully productive weekend, mon ami.

There is something meditative about sanding. I've been doing a fair bit of it myself lately.

Watching with interest,

Brian da Basher
Title: Re: MiG-3Y Utka
Post by: Tophe on March 11, 2018, 08:13:36 PM
Continuing to glue and support with pieces of sprues. This is impossible this way for most of you, serious modellers, but as I ignore the underside, it is all right for me... ???
Title: Re: MiG-3Y Utka
Post by: ericr on March 11, 2018, 09:00:47 PM
Continuing to glue and support with pieces of sprues. This is impossible this way for most of you, serious modellers, but as I ignore the underside, it is all right for me... ???

that is an interesting method  ;) you are right, it makes it possible to strengthen the things from below
Title: Re: MiG-3Y Utka
Post by: Tophe on March 11, 2018, 11:17:16 PM
Thanks!
And this is less shocking with a few drops of paint making the extra parts and "normal" parts look like each others:
Title: Re: MiG-3Y Utka
Post by: Tophe on March 12, 2018, 12:57:49 PM
Painting the main side now, like a normal (solid) model:
Title: Re: MiG-3Y Utka
Post by: Tophe on March 13, 2018, 12:23:08 PM
The model is finished! The first vacform of all my life! Almost a success (according to my poor standards)!
Title: Re: MiG-3Y Utka
Post by: ericr on March 13, 2018, 03:21:36 PM
 :smiley:

the cockpit is very streamlined

Title: Re: MiG-3Y Utka
Post by: Brian da Basher on March 13, 2018, 05:28:11 PM
That really finished up nice, Tophe!

It has a very fast, sleek look, like a racing plane.

Well done, mon ami!

Brian da Basher
Title: Re: MiG-3Y Utka
Post by: Tophe on March 14, 2018, 02:29:54 AM
Thanks!

the cockpit is very streamlined
In fact, the cockpit is flat, like on a few racer prototypes of the 1930s...
Title: Re: MiG-3Y Utka
Post by: Robomog on March 16, 2018, 05:49:03 AM
I tend to treat vacforms as a scratch build project, good luck with this on Tophe, it's looking good so far.


Mog
>^-.-^<
Title: Re: MiG-3Y Utka
Post by: Tophe on March 17, 2018, 10:21:19 PM
good luck with this on Tophe, it's looking good so far.
Sorry, there will be nothing further for me: my models have no landing gear, no roundels, no engine exhausts, seldom propellers... ??? ;)