# Making a cylinder



## Fozzie (May 25, 2009)

Any suggestions on how to make a cylinder out of sheet styrene that doesn't have a flat spot where you have glued the seam? Thanks.


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## kenlee (Feb 11, 2010)

First, cut the sheet about a half inch wider than the width required to produce your cylinder. Roll the plastic into a cylinder shape smaller than the one you want to produce and secure it by tightly winding it with string. Take a blow dryer and blow hot air through the cylinder, getting it hot, but not hot enough to melt the plastic. Dunk it into cold water (the cylinder, not the blow dryer). Depending on the thickness of the plastic you may have to do this several times to get it to hold the shape. Trim of the excess width to produce the size cylinder that you need, trim both edges. This usually works best on plastic stock .040 and thinner and on cylinder shapes larger than 1 inch. If the excess that is trimmed off has the same curve of the cylinder, it can be used to re-enforce the seam.


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## Dyonisis (Nov 11, 2009)

How big does it have to be? If you have an ink marker - the fat kind, you can cut the styrene to size. Wrap it in a circle to see where it ends for the circumference you need, then mark it. Cut the excess away. Wrap this carefully around the outside of the marker, then wrap rubber bands around it to secure it. You'll have to wrap all the way up, and down completely to keep it from bulging out in places. Then put it in a sauce pan of very hot water - as hot as you can stand it, or use hotdog tongs to remove it. Leave it in the water for fourty seconds. Remove it, then run cold water over it right away. If you leave it in too long, it'll leave lines from the rubber bands, but if the styrene is thick enough (0.40") thick you can sand them out. You just don't want to. It's hard to sand it evenly once the rubber band marks get into it. I filled mine with superglue - the purple Rob Smith stuff. I sanded it with 220 grit glued to a popcicle stick. Either way, if you can do this without getting lines in it, you can do this as many times as you need without complications. It depends on how big a cylinder you need.

The only other thing I can think of (if you need a bigger shape) is to get a PVC pipe a little smaller than the diameter you need, and put wax paper over it. Tape it to the pipe, then wrap your styrene around it. Mark where it joins the other edge, then cut off what you don't need. Tape it around many times to keep it from coming off. Take a hair dryer to it - get it hot enough to make the styrene conform to it. Then once you've got the shape you want, glue the edges together bound securely with tape. After the glue dries you should be able to remove the cylinder from the PVC pipe as long as you don't do it too tightly. If you have a deep broiler pan you can do the hot water thing if your cyliner isn't too long, but big around. I hope this will help somehow. :wave:

~ Chris 

Edit: Damn, Ken - I was writing this as you were posting. You beat me to it!​


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## Fozzie (May 25, 2009)

Thanks, guys. Your responses should prove to be very helpful. :thumbsup:


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## kdaracal (Jan 24, 2009)

> _(Dunk it into cold water (the cylinder, not the blow dryer)._


:lol:


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## steve123 (Feb 9, 2009)

I could tell my parents hated me. My bath toys were a toaster and a radio. 










Steve


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## Xenodyssey (Aug 27, 2008)

Thanks guys.

I have a project that requires both a large cylinder and and cone and will try these suggestions for it.


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## kdaracal (Jan 24, 2009)

Xenodyssey said:


> Thanks guys.
> 
> I have a project that requires both a large cylinder and and cone and will try these suggestions for it.


From the guy who scratched out the F-302. Awesome!


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## Fernando Mureb (Nov 12, 2006)

steve123 said:


> I could tell my parents hated me. My bath toys were a toaster and a radio.
> Steve


:lol::roll:


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## Dyonisis (Nov 11, 2009)

steve123 said:


> I could tell my parents hated me. My bath toys were a toaster and a radio.
> 
> 
> 
> ...


 Hey, Steve. You were my inspiration for the pyro shot I posted my X-wing thread. :wave: I just wanted to show that not everyone only posts their good work. I wanted everyone to see what true modeling stupidity looks like when you're not paying attention to what you're doing. Thanks again. ~ Chris


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## Xenodyssey (Aug 27, 2008)

kdaracal said:


> From the guy who scratched out the F-302. Awesome!


Doing round or curved shapes has always been hard for me. The Puddlejumper I did kinda cheat with using the planking method.

But I've got a couple of genre submarines I'd like to model and all of them have curved hulls in some way.


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## Fozzie (May 25, 2009)

Xenodyssey said:


> Doing round or curved shapes has always been hard for me. The Puddlejumper I did kinda cheat with using the planking method.


What is the planking method?


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## Xenodyssey (Aug 27, 2008)

Fozzie said:


> What is the planking method?


What I call the planking method (I don't know what it really might be called) is building a model like you would a wooden ship. Create the supporting structure, front end , back end and ribbing inbetween. Then lay down thin strips of plastic lengthwise. The smaller the scale, the thinner the strips. For the Puddlejumper I then overlaid plastic plates of thin plastic .020 I think it was which bent into a curve easily.

I'd imagine you could also just apply putty over the "planks" and then sand them back to get a better finish.

What gave me the idea was the Space Station One thread that was in the modelling forum I think a little while ago.


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## Dyonisis (Nov 11, 2009)

That's not cheating! It's a neccessity when you don't know of any other way to do something, or there's no other easy, or possible way to do the same thing. Remember, neccessity is the mother of invention, but the CAUSE of neccessity is the father of invention! ALWAYS. Cutting thin styrene strips to cover a frame is as old as the hills. This is only suggested when you can't make a cylindrical shape by normal means.


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## Xenodyssey (Aug 27, 2008)

Yes it is an old technidue. Also when you do it in multiple layers you end up with a very robust model. It feels very solid.


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## Dyonisis (Nov 11, 2009)

The only thing to remember is that the heavier something is, the easier it is fall off the shelf and break - in many pieces!  Multiple pieces gives it more rigidity as each one has more resistance in layers. The spaces between the strips being inhabited by the CA, or superglue helps to absorb the impact rather than forcing the plastic to take it. When the plastic is exposed to this it takes the force of the impact, and spreads it out in one piece - much worse outcome in any case. TENAX is for plastic welding where you don't want pieces to break easily such as small delicate parts. Another thing to remember is, superglue will break right at the seams - not completely through a part as it's so brittle that it cracks along the glue joint. There are advantages, and disadvantages to different construction techniques, but a solid object has the most resistance. Unfortunately, it also has the most weight! 

There are also foam shapes that you can buy at Jo-Ann fabrics. I was just there last night. It isn't just for women who want to sew - it has MANY things for crafts too! I was very inspired when I went into the wooden shapes, and supplies section. Maybe you could look up some of these shapes (cylinders, and cones) for your project to help make it go faster? 

~ Chris​


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## Fozzie (May 25, 2009)

All very interesting stuff, guys. Thanks. I'll likely be trying to make the cylinder this weekend. My experiments last night with some .30 styrene were a bit hit and miss, but I learned a lot. The cylinder I need to make has to be hollow, about 2" in diameter, and about 3" long.


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