After Lurking, started my own armor; I can't cut 45 degree or bevel correctly..?

Hi there,

I've been lurking here for a while and finally made the commitment to cosplay this year for NYCC. I got all the tools, a sharpener, a cutting mat, EVA Foam, Blades, X-Acto Knives, Etc Etc.

I started working on my ODST cosplay armor from DaFrontLineTrooper's tutorials. I've spent a few hours just sizing the shins until I got it all figured out.

I first printed it out on paper, then transferred it to cardboard for some measurements.

Finally, when I was happy, I started to cut the foam.

In my first cut, I thought it was kind of weird. I used a fresh, out of the box knife, and got a rough edge. However, most of my other cuts were fine.

I noticed that, long, straight or curved cuts can be flawless; but close and cornered cuts are jagged and rough.

Part of the tutorial requires bevels and 45 degree angles, which I just can't do. I tried everything, sharpnening, new blade, x-acto, and can't seem to cut the details in.

For example, If I'm trying to cut a bevel, I can cut the 90 degree half way fine, but when I cut into it with a 45 degree, it is almost spongelike and mush, won't cut.

As for 45 degree angles, if I'm doing it on a small piece, it'll keep mushing together too. As for corners. Below are some images of mine.

This is my attempt at a 45 degree angle.



This is my attempt to bevel, the 90 degree is fine.





45 degree isn't...



Progress So far...




Thanks everyone, it looks like Andrew Cook in the videos can cut through these things like butter. I just can't seem to do it.

EVA Foam I'm using:

http://www.amazon.com/gp/product/B001E4XL3E?&redirect=true&ref_=oh_aui_detailpage_o03_s01

try and do multiple passes on the corners, only taking a little at a time, it should help with the roughness of the cuts

tahu653 said:

try and do multiple passes on the corners, only taking a little at a time, it should help with the roughness of the cuts

Click to expand...

The problem is I feel like the foam is just too bouncy for it to cut detail. I can cut large lines quite fine but the detailing like bevel is impossible.

multiple passes will make a finer cut, as you arent trying to go through as much material. just a bit of patience and repitition will get those nice details to shine through

tahu653 said:

multiple passes will make a finer cut, as you arent trying to go through as much material. just a bit of patience and repitition will get those nice details to shine through

Click to expand...

I know, but as for the beveling and the 45 degree angles, the main issue is that it won't cut at all. As in, for a 45 degree bevel affect after half 90 degree cut, it doesn't pierce the foam and the blade is sharp enough.

do oyu have the plade basically level with it, so thyere is barely any angle, or up >45 degrees from the foam?

tahu653 said:

do oyu have the plade basically level with it, so thyere is barely any angle, or up >45 degrees from the foam?

Click to expand...

I'm doing a direct 45 degree cut after the 90 degree cut to make a bevel affect, the 45 degree cut turns to mush because it won't piece such a small area. As in, the only way to get clean cuts is by cutting large,curved or straight lines, not details.

this is what im asking, if you are doing it the first way, your gonna get a bad cut, other than the second one, which will get a smoother cut. a sharper angle than that can be used for better results, in my opinion

tahu653 said:

View attachment 14089

View attachment 14090

this is what im asking, if you are doing it the first way, your gonna get a bad cut, other than the second one, which will get a smoother cut. a sharper angle than that can be used for better results, in my opinion

Click to expand...

I tried the second way holding; the problem is it gets a mush affect because it keeps sinking into the first cut. When I start the angled cut for the bevel affect, it automatically sinks into the first cut making it really messy.

y

i cant see the photo, making it kind of hard to give feedback

tahu653 said:

i cant see the photo, making it kind of hard to give feedback

Click to expand...

Dang, thanks anyway. I can cut clean lines through larger cuts; but it's just those small ones... I read about wood burners...maybe I'll use those for detailing.

Thanks for your help though!!

Hey beyonddead, it looks like you're linking to photos that are stored privately as an e-mail attachment (or in some other method via gmail). Since they're stored privately, they won't show up for anyone on the forums; I just tried going to the link manually and was given a '403: Forbidden' error. You need to rehost the images publicly on a site like imgur for us to see them.

Without seeing the images, the first thing that comes to mind is that foam dulls the blade quickly (moreso than you might expect), so you need to keep a file/sharpener of some sort to hand when cutting foam and make sure to sharpen the blade regularly, otherwise you start coming up against unnecessary resistance and the foam begins to tear rather than cut when you drag the blade through it. It's easy to see when this is the case: here is an example of what it looks like on a straight (90 degree) cut:



You can see that, rather than a nice clean cut, there is an uneven surface created by lots of mini-tears created by dragging a dull blade through the foam. If this looks anything like your results, this may be the problem. I know you put on your first post that you felt that blade sharpness wasn't a factor, but I thought I'd include it anyway, since it's often pretty easy to see when this is the case from the result of the cut on the foam. The fact that you highlighted 45 degree cuts and non-linear cuts as particular problems also made me think this because of the extra surface area in a 45 degree cut and the stresses exerted on the foam/blade changing throughout the cut on non-linear cuts often exacerbates the damage caused by a dull blade.

It could also be, as tahu653 suggested, an issue with the cutting technique, making an otherwise sharp blade act dull. If you have a look on YouTube for in-depth tutorials on foam armour, they will often include footage of themselves cutting the foam (example with a 45 degree curved cut (starts at 2:12)). Although they don't explicitly address cutting form, it should be easy to see if there are any major differences between their technique and your own.

Hope this helps! If not, rehost the images and repost them here, and we'll have another go at diagnosing the problem.

You mention that you cut at 90 degrees first, then try to bevel it to 45*. While this can work, I personally try to think ahead, and cut at an angle on my first pass (occasionally I'll do more than one pass for very tight detailed areas, but I find it looks far cleaner to cut just once).

In this pic, my cuts were all done in one pass, with a fresh blade. Granted I use flat razor blades with no handle, not an x acto. Also realize I cut from the other side... this is underside.

I do the same as FlyingPhil, always cut angles on the first pass.
I use scalpel blades though.

When I know I'm going to have issues with a cut or if I know I'll need to clean it up (because I tend to use blades slightly longer than I should), I go ahead and start with a 90 degree angle, then, based on the thickness of my foam, I mark where I want the angle to start to where I want it to end and use my Dremel to get the angle I want.
What I mean is, good luck trying to get a 30-degree angle only using a blade. For 1/2'' Foam, I mark 0.87'' away from where the edge I want the angle to meet up to, and then I dremel that angle from the bottom edge to the line at the top.

A Dremel is a $40 investment (+$15 for an engraving kit), though Harbor Freight has a nameless one for $10-15 that comes with a good set of accessories.
It was a struggle for me to use at first, but it is a skill you have to develop and recognize you might screw up a few pieces accidentally, and sometimes I just call it "battle damage" when I slip to the wrong side and cut.
You have to be careful when you make it to the end of the line because the last edge of the foam likes to get pulled up, making it easy to mark up the opposite side when it happens.
Kinda sucks that rotary tools only rotate in one direction, but you get used to it.