Bevel Cut

[Big John]

I all I am looking around the site trying to get as much information as I can. :wacko

I have a question when making a bevelled cut 45 30 degree on EVA foam

Once you have drawn around your template do you cut the bevel were needed as you cut the shape out or do you cut the shape out using straight cuts and then cut the bevel??? :confused

Hope this makes sense.

 

[Lazarus215]

I haven't worked with Foam, but from my time as a welder I'd imagine you could do either. Personally, I'd cut the foam first, then cut the bevel so that the angle lined up perfectly with the bottom edge. (It'd just be easier to see the bottom edge after you removed the piece from the chunk of foam)

 

[RobTC]

EVA foam can largely be worked like any other solid material. You cut out the materials straight, then sand down the bevels. Just like you would with MDF or steel. Most people use a Dremel, I assume it's possible to use a disc sander though. It requires a very light touch, and the fluff will go away when you heat-seal the foam.

 

[Big John]

I'd cut the foam first, then cut the bevel so that the angle lined up perfectly with the bottom edge. (It'd just be easier to see the bottom edge after you removed the piece from the chunk of foam)

Thanks Lazarus215, That what I was thinking because if you cut the bevel when using the template it would make the foam piece that you have cut out bigger than the template, if there is any one that can confirm this I would be most greatful.

 

[Deleted member 19386]

Once you have drawn around your template do you cut the bevel were needed as you cut the shape out or do you cut the shape out using straight cuts and then cut the bevel??? :confused

From all the research i've done on eva foam costume making, your best bet is to cur your peices out straight then do your bevel

 

[Corweena]

I do a combination of both. Before even cutting pieces, I figure out which edges need to be straight cut, and which need to be beveled (and in which direction, in or out). It doesn't change the size of your pieces, if you do it right. So you trace the piece out. Then lightly score the line to have a cutting base. From there, you angle your blade either in or out. and slowly slice the angle away. It may take a couple times. Having a sharp blade is key. I'd recommend buying a 100-pack of scalpel blades. After I cut the foam, I will then pull out the dremel and smooth the bevel and/or change the angle if needed. I've found that with a grinding bit on the dremel, it wants to bite too hard on straight cuts, and you end up with a lumpy and bumpy line. If you cut first, you then have a straight top line (aka the visible portion), and can sand the lower portion to increase the angle if needed.

So planning is really key. I print and cut out my paper templates, then work in sections and tape them together to verify the fitment. In some cases I'll modify things here or there, especially if you need certain pieces to fit a bit better.

ANd if you have a belt sander, use that. 10x easier having a solid sanding base, and moving the piece as needed, than trying to hold both a dremel and piece steady to get a straight line. I'll probably be grabbing a cheap one soon, just for ease of use and convenience.

 

[FlyinPhil]

X2 on what Corweena said.


Personally I like to cut my bevels as I'm cutting the part out of my sheet of foam, as it leaves a nice consistent angle right to the edge. I occasionally make the mistake of cutting some edges straight, though, and have to go back and bevel them with a blade. It doesn't make quite as clean of an angle, due to foam being rather pliable and fighting against the cut, but you can clean up the edge with power tools as others have mentioned.

 

[Big John]

Thank everyone for you advice, I think I know what I am doing now. :wacko

 

[Skoopa92]

If you're using a hot knife it's best to cut the shape out first, then bevel cut. Because the barrel of the hot knife will burn against the foam while cutting at an angle. I think if you're using a regular knife, cutting the bevel with the shape would be handy

 

[Dirtdives2424]

you could also use the hot knife to "stamp" down the inside edge to get the bevel right in the front. this way you can check the seam first before you move on to the next piece. if you cut, sometimes the cut is too deep and the straight edge you had will be gone. Take it slow and easy and the seam will line up just right.

 

[mandoman247]

I haven't started my foam armor yet but from what I've read cutting straight first then cutting the bevel after seems the way to go. Using a dremel tool is something that alot of the people on here suggest also.

 

[FlyinPhil]

I haven't started my foam armor yet but from what I've read cutting straight first then cutting the bevel after seems the way to go. Using a dremel tool is something that alot of the people on here suggest also.

If possible, I'd advise against this. From my experiences in building my suit/ weapons, you get a far cleaner angle and edge when you bevel as you cut the part out.

 

[mandoman247]

If possible, I'd advise against this. From my experiences in building my suit/ weapons, you get a far cleaner angle and edge when you bevel as you cut the part out.

Thanks for the input FlyinPhil. How do you know where to bevel though? By looking at the pepakura model on the computer? Actually I think I just answered my own question.

 

[FlyinPhil]

Thanks for the input FlyinPhil. How do you know where to bevel though? By looking at the pepakura model on the computer? Actually I think I just answered my own question.

Haha that works for sure! It just takes a little planning ahead. I completely scratch built all my foam parts, and didn't have the luxury of seeing where all the parts meshed beforehand, so pepakura designer will definitely be able to help you out in that regard!