Scratch building methods

[mash3d]

Scratch building methods


Hi, I'm planning on doing some scratch building. Mostly of hardsurface objects like ships etc.
My current plan it to draw out the cross sections, then cut themout of sheet styrene or bass wood.
Connect the cross sections with tubes or fill in the space betweeneach cross section with Pink insulation foam board.
Then cover it with Styrene sheets and build up exterior detailsfrom there.


One of my main questions is how to you attach the Sheet Styrene tothe foam board? I'm trying to find a glue that will not eat away andthe foam board leaving a hollow space.


Also lets say I was to skip the foam board all together and justattach the sheet styrene to the cross sections. How to you get thesheets to stay attached to the cross sections, especially if they arecurved.
I'm worried that just the cross sections will not have enoughsurface space to hold good weld.


Thanks,

 

[IEDBOUNTYHUNTER]

I would skip attaching styrene to foam board. wont last long. Not sure how curved the hull is your doing . One way is to get your cross sections, fill with foam fiberglass and bondo. pull a mold and make a glass Hull.

Another way is to get your cross sections and glue wood planks on. thin balsa and glue that to the stations. better than styrene.

then depending on the curve again. you can always make a good plug and Vac form it. again this depends on the shape of the hull.

if post some pics of what your making would be better to figure out the best way to make it.

 

[mash3d]

Hi, thanks for the info. I'm working out of a small apartment so working with fiberglass could be a bit of a problem.
I'd need to make a vacumfoming machine also. I'm just doing smaller scale models. Maybe 24 inches or so.
At the moment I'm just starting out with simple designs, more planar and not to many drastic curves.
http://babylon5.wikia.com/wiki/Raider_fighter
If you use thin balsa wood planks what would be a good way to seal them?

 

[rbeach84]

Aye, different projects may demand different strategies & there is usually more than one way to get a good result (sorry if stating the obvious...) Given what you are doing, you may want to investigate some of the techniques used by paper modelers. PAPERMODELERS.COM is a fine PM forum to visit and check out just what is possible with that medium.

Regards, Robert

 

[mash3d]

Thanks,I've built a few paper models over the years.
Myoriginal plan was to make the model similar to some of the betterpaper models that have internal cross sections for support.
Thehard part is getting the original design unfolded.
That'swhy I'm starting with a simple design without a lot of complex shapesin it.
Ihave pepakura and Modo so I can build a 3d prototype and get thecross sections from that.

 

[Gattaca]

If you don't have a vacuum former I would recommend you just cut the shapes you need and glue them together using methylene chloride solvent glue. You can add ribs and triangle braces where ever you need. I've used paper craft as blueprints to build my models. As for curved parts you can bend the styrene over a shape then laminate more layers over using the solvent glue, when you have a few layers it should hold it's shape.
Check out my blog, I've done just what you are planning on doing and I've made several tutorials on scratch building..

http://gattaca67.blogspot.ca/2012/09/yt-1000-part-1-shaping-yt-1000.html

 

[crackerjazz]

Hi mash3D, you can probably use styrene planks such as Roback did on his build. I was thinking about doing something similar on a build I'm planning.

http://www.therpf.com/showthread.php?t=173853

One guy did the same and used CA glue in between the planking and it looked really smooth after sanding.

 

[mash3d]

Thank you, Those posts are exactly what I needed to see. It's very helpful to see someone elses model from start to finish.
Gattaca, it was nice to see how your YT-1000 was made and the posts you made on resin casting were very helpful.
I've seen other posts were people were using foam in between cross sections.
I'm now assuming they were doing that to just to make the Buck, or base part to be vacum formed over?

 

[crackerjazz]

Excellent stuff, Gattaca! Hi mash3d, I think if you aren't going to vacuform you won't really need to fill the spaces. The styrene planks will follow the ribs and can be sanded to shape. I'm planning to use thicker styrene on mine -- maybe 0.75mm.