How to remove a foamboard channel cleanly?

[paulcurtis]

I am fine at making the cuts for a 5mm channel without going through the bottom layer of paper. I can cleanly 'crack' open the parallel cuts. But when I use my fingers to ease away the foam to be discarded, sometimes it comes away cleanly, and sometimes it leaves a shallow layer of foam on the paper. I can clean it up with a knife of course, but am I doing something wrong, or, is there foamboard, and foamboard ... Any hints for the technique of removing the channel cleanly please?

 

[AIRFORGE]

I am fine at making the cuts for a 5mm channel without going through the bottom layer of paper. I can cleanly 'crack' open the parallel cuts. But when I use my fingers to ease away the foam to be discarded, sometimes it comes away cleanly, and sometimes it leaves a shallow layer of foam on the paper. I can clean it up with a knife of course, but am I doing something wrong, or, is there foamboard, and foamboard ... Any hints for the technique of removing the channel cleanly please?

You're doing it right. Every FB sheet is different. Sometimes it works, sometimes you need to clean the leftovers. It's more of an art than a science. Just find what works for you.

 

[Mr NCT]

I am fine at making the cuts for a 5mm channel without going through the bottom layer of paper. I can cleanly 'crack' open the parallel cuts. But when I use my fingers to ease away the foam to be discarded, sometimes it comes away cleanly, and sometimes it leaves a shallow layer of foam on the paper. I can clean it up with a knife of course, but am I doing something wrong, or, is there foamboard, and foamboard ... Any hints for the technique of removing the channel cleanly please?

I'm with @AIRFORGE, every very foam board is different. You might try making a chiseled edge on a barbecue skewer, that's what I use to clean out the foam boogers.

 

[Houndpup Rc]

I am fine at making the cuts for a 5mm channel without going through the bottom layer of paper. I can cleanly 'crack' open the parallel cuts. But when I use my fingers to ease away the foam to be discarded, sometimes it comes away cleanly, and sometimes it leaves a shallow layer of foam on the paper. I can clean it up with a knife of course, but am I doing something wrong, or, is there foamboard, and foamboard ... Any hints for the technique of removing the channel cleanly please?

Are you using DTFB? I have found that the paper on the side with the sticker (Or is it the other side...You remember @Mr Man?) comes off easier...could be sometimes you cut on one side, other times on the side that's harder to remove....I also find that if I didn't cut deep enough on the score, I will get the little bit left over.

 

[Mr Man]

The side with the sticker 👍

 

[Houndpup Rc]

The side with the sticker 👍

That's what i thought 👍

 

[paulcurtis]

Hi, thanks for the replies, very helpful.

I don't know what DTFB is (I am in the UK). I have assumed - probably erroneously - that foamboard is much of a muchness, but perhaps quality does vary. I have only used the cheap stuff from Amazon that comes in packs of ten A1 sheets, and by and large in model durability it has been fine. I think I am cutting deep enough as I can open the cut and fold it back on itself. So I have wondered if the foam itself does not have a completely uniform density, and sometimes where the foam may have a seam of a less density near the bottom of the cut, then it will break along that seam rather than cleanly away from the bottom. Dunno?

I like the BBQ stick idea to clean off though, thanks. I've used a knife until now, probably unnecessarily abrasive

 

[AIRFORGE]

Hi, thanks for the replies, very helpful.

I don't know what DTFB is (I am in the UK). I have assumed - probably erroneously - that foamboard is much of a muchness, but perhaps quality does vary. I have only used the cheap stuff from Amazon that comes in packs of ten A1 sheets, and by and large in model durability it has been fine. I think I am cutting deep enough as I can open the cut and fold it back on itself. So I have wondered if the foam itself does not have a completely uniform density, and sometimes where the foam may have a seam of a less density near the bottom of the cut, then it will break along that seam rather than cleanly away from the bottom. Dunno?

I like the BBQ stick idea to clean off though, thanks. I've used a knife until now, probably unnecessarily abrasive

DTFB (Dollar Tree Foam Board) is a bit of a misnomer. It's actually Adams Readi-Board that is sold at Dollar Tree stores in the states.
Adams also makes Flite Test Foam Board (brown, white) and Flite Test Maker Foam (white).
Other brands are heavier and can sometimes be more difficult to peel the paper or remove the foam from cavities but will still work.

 

[paulcurtis]

Thanks AIRFORGE. I tried to find the same brown board Josh Bixler uses here in the UK, with no success. I think one advantage of the brown board is that it is waterproof, whereas the normal stuff delaminates when wet, unless it's been waterproofed.

I use that thin plastic parcel tape in various colours to cover all the foamboard after gluing and installing servos. Not only does it colour it, it waterproofs it, and adds strength to the joints too. And it is pretty light.

 

[Foamforce]

What works well for me is to first make sure that your cut goes all the way to the other side. I used Josh’s dulled knife technique. I run the dulled knife through the cut a couple times until I can feel that it’s cleanly on the paper on the other side. After that, I fold over (180 degrees) the foam board at the outer edge of the channel, so that one side of the fold is on the bottom, and the other side is on top along with the foam that you want to remove. With everything held down flat, I get all four of my fingernails between the top side and the foam that I’m removing and pull the channel foam straight away. In most cases, it will pop away cleanly with this technique.

 

[Houndpup Rc]

Thanks AIRFORGE. I tried to find the same brown board Josh Bixler uses here in the UK, with no success. I think one advantage of the brown board is that it is waterproof, whereas the normal stuff delaminates when wet, unless it's been waterproofed.

I use that thin plastic parcel tape in various colours to cover all the foamboard after gluing and installing servos. Not only does it colour it, it waterproofs it, and adds strength to the joints too. And it is pretty light.

DTFB (Dollar Tree Foam Board) is a bit of a misnomer. It's actually Adams Readi-Board that is sold at Dollar Tree stores in the states.
Adams also makes Flite Test Foam Board (brown, white) and Flite Test Maker Foam (white).
Other brands are heavier and can sometimes be more difficult to peel the paper or remove the foam from cavities but will still work.

Oops, sorry! I guess I should have mentioned that! 👍