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What is the most accurate way to cut 2 inch foam?

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  • Member since
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  • From: "Steel, Steam and Thunder"Fort Wayne, Indiana
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Posted by TheK4Kid on Sunday, January 17, 2021 9:39 PM

Cutting foam on a band saw will dull the blade quickly!

I also build and fly RC model airplanes, and can easily replicate some kit built airplanes out of foam quickly

All I need are the plans.

I do have a gravity operated foam cutter called "Feather cut" by Teko, with six bows and a power supply using nichrome wire, or very then welding wire.

I use templates made from formica.

I purchase my pink foam in varrying thicknesess from a local Menards store.

In the warmer weather I cut most of my foam outside, but using a hot wire setup, I can do it all insidebecuse a hot wire doesn't produce any dust particles.

If sanding is required, this is done outside!

Scraps of foam can be used tomake foilage for trees, etc chopped up in a second hand blender. Hpowever less than a mile from my home in the country is an Amish sawmill that makes pallets for industry.

I take a couple empty heavy duty trash bages and they simply shovel them full of sawdust for free.

 

My HO layout uses a 2 inch thick pink foam base laid inside a bed lattice type of framework. THree tables joined end to end forming a 6 foot wide by 24 foot long layout base.

I use Woodland Scenics foam for my track base.

My reasoning for doing this is if I ever relocate, I can unbolt the three tables, after removing all loose items, then unbolt the legs  turn them up on their side and easily carry them up my basement staircase with one guy on each end, as they are fairly lightweight.Then later easily reassemble them in a new location.

 

After seeing several friends have to destroy their layouts with saws and chainsaws to move them, I decided on making mine with a foam base.

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Posted by mrrdad on Sunday, January 10, 2021 12:52 PM

Not that this is practical for what the OP is trying to do, but I've had good success cutting it with a fine tooth blade on a table saw

 

Ed

Semi newbie HO scale modeler coming from the O scale world

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Posted by The Milwaukee Road Warrior on Sunday, January 10, 2021 9:22 AM

I failed to mention that in my case I had already glued down my sheets to my plywood benchwork, so when it came time to cut with the jig saw nothing moved or bounced around.  That may not be practical for others depending on how/where they plan to use the foam: they may have to cut first and glue later.

Andy

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Posted by BigDaddy on Sunday, January 10, 2021 8:11 AM

Follow up:    I got the Bosch blades.  6" was all I could find.  It has rounded serrations and they wanted to grab the foam and bounce it up and down.  That's easily overcome by putting more pressure on the jig saw, but my B&D jig saw would tilt from being perpendicular. 

The cut was as smooth as it could be and no dust at all.

Henry

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Posted by The Milwaukee Road Warrior on Friday, January 1, 2021 10:30 AM

Henry, I don't know if its the BEST way, but the only way I've ever done this is using a jig saw.  I had the same thing happen with small areas of foam overlapping.  I didn't get any special kind of blade, I just used the same blade I was cutting plywood with, and I carefully ran along the edge.  It worked fine for me but I don't know how wide your tolerance is.  

In some of the larger overlaps I glued the entire sheet down, then measured in from the edge of the foam to the edge of the benchwork on the underside and transferred that to the top side in enough places that I could draw an accurate line to cut along.  It worked pretty good overall.  I will have some small areas to fill in later.

Andy

--------------------------------------------------------------------------------------------

Milwaukee native modeling the Milwaukee Road in 1950's Milwaukee.

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Posted by rrinker on Monday, December 28, 2020 2:22 PM

 For cutting the long way for my previous layouts (I had sections less than 2' wide), I used a long straightedge to hold a straight line, and I used a large putty knofe (like a 6" one) that I sharpened on one side and corner to score the foam. Multiple passes, not pressing hard, so I could follow the straight edge, until it was almost through along the entire length, then it snapped off cleanly. No foam dust - which was important, since I was working inside, in an apartment.

                                     --Randy

 


Modeling the Reading Railroad in the 1950's

 

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Posted by SeeYou190 on Sunday, December 27, 2020 10:38 PM

BigDaddy
Found my Foam Factory Hot Wire.  The thing that looks like a skinny ice pick is of no use at all cutting 2" foam. 

My youngest daughter "stole" my Hot Wire Foam Factory when she moved out.

I bought a foam knife on Amazon from China, but I seriously doubt it would cut 2 inch foam any better. It was a lot less expensive.

-Kevin

Living the dream.

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Posted by wvg_ca on Sunday, December 27, 2020 9:46 PM

BigDaddy

Found my Foam Factory Hot Wire.  The thing that looks like a skinny ice pick is of no use at all cutting 2" foam. The ice pick bogs down and bends after about 6"  In retrospect I didn't need to trim this 1" half lap, but it proved it wouldn't cut 2" if it wouldn't do 1"

 

can you turn up the heat a little, or is it preset ??

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Posted by BigDaddy on Sunday, December 27, 2020 5:32 PM

Found my Foam Factory Hot Wire.  The thing that looks like a skinny ice pick is of no use at all cutting 2" foam. 

The local foam has a half lap joint on the sides.  The ice pick bogs down and bends after about 6"  In retrospect I didn't need to trim this 1" half lap, but it proved it wouldn't cut 2" if it wouldn't do 1"

Henry

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Posted by BigDaddy on Saturday, December 26, 2020 11:30 AM

9 moving boxes later, my Hot Wire is still MIA, unless it at the very bottom of one of the boxes.  I found my electric kitchen knife but no cord and similar cords I have don't fit.

I guess it will be the jig saw. 

Henry

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Posted by SeeYou190 on Saturday, December 26, 2020 11:05 AM

BigDaddy
How do I cut the curves and the straight lines to have minimum touch up work?

Track fiddler
I have found the smoothest most accurate way to cut foam is a fine-tooth blade in a jigsaw Henry.

I went through a lot of foam with the girls making CosPlay props.

The method described by Track Fiddler is the best way we found. We used a drywall square clamped to the foam to guide the jigsaw for straight cuts. Use a fine tooth blade intended for metal cutting. I think the one we used most was 28 teeth per inch. Go slow so you do not melt the foam.

It makes less dust than you will expect. This was a welcome surprise. Do not have a ceiling fan turned on while you cut, and wear an N95 mask and safety GOGGLES!

We also used a detail sander to polish the cut foam, but there is no need to do this for model railroading purposes.

-Kevin

Living the dream.

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Posted by wvg_ca on Friday, December 25, 2020 9:17 PM

freehanding the hot wire cutter is not really a problem at all... i just use two straight edges bedide each other ,     one on each side of the workpiece, that way i can wiggle the hot wire cutter and i still get 90 degress, as long as i run the wire against the guides , 

it takes longer to type this than making the actual cut, lol                                          

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Posted by Track fiddler on Friday, December 25, 2020 6:33 PM

BigDaddy

Experience.  If you sand foam outside, not only are you and the shop vac hose covered by small blue or pink particles, the grass and mulch is too.  And the later doesn't vacuum up easily.

It also give me flashbacks to my drywall hanging adventures. 

 

Okay I got this Henry!

Never mind the grass and the mulch.  That can stay outside.

It's a wet-dry Shop-Vac isn't it?  Spray it off with the hose. 

Run inside quick.  Throw your clothes in the laundry Basket and your wife will wash them for you.

Jump in the shower as the same principle as the Shop-Vac, same after hanging or sanding drywall.

 

Lather rinse repeat.  Kids don't try this at home and only follow directions with adult supervisionStick out tongue

 

 

LaughI'm sorry but I just had to, ...TF

 

S.O.S.  You're probably right!  I've been working with pink foam for so many years I probably don't even sense that it is there anymore.  I hope it isn't toxic because I was cutting it on the kitchen counter again today before I made Christmas Dinner.

For all I know, ...Perhaps it is like pepper and ads a distinctive flavor to the foodLaughWhistlingWink

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Posted by Pruitt on Friday, December 25, 2020 5:55 PM

I use a serrated knife to cut the foam. Not as neat as TrackFiddler's work by a long shot, but it does the job well enough, and any gaps or holes (and the occasional blob of foam does rip out) can be filled with Celluclay or Sculptamold during the scenery building process.

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Posted by BigDaddy on Friday, December 25, 2020 5:47 PM

Track fiddler
Where did this big fuss and phobia come from about the static and mess from foam?

Experience.  If you sand foam outside, not only are you and the shop vac hose covered by small blue or pink particles, the grass and mulch is too.  And the later doesn't vacuum up easily.

It also give me flashbacks to my drywall hanging adventures. 

Henry

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Posted by Track fiddler on Friday, December 25, 2020 12:04 PM

Respectfully speaking no matter what you do there's always a mess.  Even when you eat you have to do the dishes. 

Where did this big fuss and phobia come from about the static and mess from foam?  Does foam have radiation in it or something I don't know about?

It's never nothing a vacuum cleaner can't take care of.  When you cut the stuff with an ultra fine-tooth jigsaw blade you can barely even see the micro particles of pink dust in the carpet fibers or on the floor.  I've even cut the stuff on the kitchen counter as a work bench and probably had some in my sandwichLaugh

 

Please read and follow these simple directions:

Dish soap for the dishes - vacuum cleaner for the foam.  Lather-rinse-repeat.  Kids Don't Try This At Home!  Follow directions with adult supervision onlyLaughWhistling

 

I'm just hoping everyone can find some humor today, after all it is Christmas!

 

 

WinkTF

 

 

 

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Posted by MisterBeasley on Friday, December 25, 2020 11:36 AM

Not terribly tidy or clean, but I used a drywall saw to cut a round hole for a turntable.  The edges were all hidden anyway.  Maybe it's not the right tool in this case, but if it's what you've got and you don't feel like going out, it's something to remember.

It takes an iron man to play with a toy iron horse. 

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Posted by mbinsewi on Friday, December 25, 2020 9:16 AM

I've used the fine tooth saw blade, works fine, not that much of a mess.  I've also used a serrated knife for carving and shaping.  Also works great.  A little less mess than the saw blade.

Merry Christmas!

Mike.

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Posted by rrebell on Thursday, December 24, 2020 11:25 AM

I clamp a straight edge to the foam and hot wire it, if you put in the work, it can look like a factory cut if that is needed.

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Posted by Track fiddler on Thursday, December 24, 2020 11:24 AM

Here ya go Henry

Hope this helps

 

 

TF

 

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Posted by BigDaddy on Thursday, December 24, 2020 10:53 AM

Thanks for the ideas.  I wish I had a bandsaw, but don't.

Bosch makes a wavy edge blade for less than those Festoon blades and I recall a video of someon grinding the teeth off a blade to make a knive edge.  Knife edge jig saw blades used to come in the assortment packs, but don't anymore.

I also saw a video were a guy made a horizontal cutter with nichrome? wire so he could make thin pieces of foam for tunnel portals.

I'll give the fine tooth blade I have a try and see what kind of mess it creates.

Henry

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Posted by wvg_ca on Thursday, December 24, 2020 8:42 AM

Lastspikemike

Did you set up the wire like a band saw blade and move the foam through the stationary wire?

yup, exactly ...

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Posted by BATMAN on Wednesday, December 23, 2020 9:55 PM

I have glued foam on the benchwork leaving a little overhang and cut it off to shape with a pistol grip hacksaw that worked great. When I put the hardboard fascia on a little spray foam or tape or something else fills the cracks depending on the place and size of the crack.

Brent

"All of the world's problems are the result of the difference between how we think and how the world works."

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Posted by wvg_ca on Wednesday, December 23, 2020 9:43 PM

i made a hot wire cutter that would cut to a foot high, and maybe a foot deep.. it was on a laminate table that held 90 degrees quite well ... het adjustment was through a light bulb dimmer to a transformer ..

i got the nichrome wire off ebay and just spring ensioned it ... the guide was adjustable and / or  removeable ..

i cut all the foam needed fr a layout 15 feet by 16 feet, and up to 9 inches high, and it was glued together with dap alex plus clear adhesive caulking ..

ps.. NO dust !

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Posted by ROBERT PETRICK on Wednesday, December 23, 2020 6:23 PM

Band saw. Some "sawdust", but not as much as you might think. Still, a good idea to have an assistant stand by running a vacuum nozzle.

Robert 

LINK to SNSR Blog


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Posted by Track fiddler on Wednesday, December 23, 2020 6:23 PM

Carolina Northern

TF,

 

Those are beautiful looking cuts, but that must have made one heck of a mess of pink dust.

 

Don

 

Nah, not really.  I live in a condo and cut it out in the living room with two saw horses.  Nothing too serious the vacuum cleaner didn't take care of.  But then again I'm not too scared of messes.  I've been making messes and cleaning them up all my lifeStick out tongue

 

The finer the better jigsaw blade you can get makes less mess than you think

 

 

TF

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Posted by Carolina Northern on Wednesday, December 23, 2020 6:14 PM

For the OP, I've been told that these do a really good job, but cannot tell you from experience. 

https://www.amazon.com/Festool-493656-Foam-cutting-Jigsaw-3-pack/dp/B0033LBOJY/ref=sr_1_22?dchild=1&keywords=foam+cutting+blade&qid=1608768662&sr=8-22

 

I'm a ways from the foam cutting stage on the current layout (past ones have used several different messy methods), but have a set on order. Always trying better ways to do things.

 

Don

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Posted by Carolina Northern on Wednesday, December 23, 2020 6:10 PM

TF,

 

Those are beautiful looking cuts, but that must have made one heck of a mess of pink dust.

 

Don

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Posted by Track fiddler on Wednesday, December 23, 2020 6:08 PM

I have found the smoothest most accurate way to cut foam is a fine-tooth blade in a jigsaw Henry.

This was one inch foam but they do sell long jigsaw blades.

 

 

TF

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