How to Fix and Fill Seams in Foam Props & Armor

One of the most frequent questions we get is how to fix and fill in seams when making props and costumes out of EVA foam. In this video, Bill shows you how to tidy up your work using Kwik Seal!
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Patterning a Foam Helmet
• Basic EVA Foam Costume...
Detailing a Foam Helmet
• Adding Details to the ...
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#PunishedProps

[@paulpethers4234]

i mean this respectfully its nice to know someone as skilled as yourself has to fix seams seeing flawless builds is off putting, its nice to know how to repair mistakes because we all make them

[@punishedprops]

+Paul Pethers Yup! Nobody is perfect.

[@mndandrews]

As someone who usually crafts in fabrics I took on the challenge of making a foam helmet. I downloaded a pattern and cut all the pieces out. The difference that I just learned between fabric crafts and foam crafts is that in foam you DO NOT cut out the registration marks of your foam (only on the paper). Guess who needed this video VERY badly after gluing up the foam pieces and having 12 holes in her helmet! Next stop the hardware store for a lot of Kwik Seal!!! thanks for having a solution to fixing my goof up!!

[@punishedprops]

Great job sticking with it!

[@SanzuFabrications]

Thank you! I was worried my gross seams weren't salvageable.

[@punishedprops]

It's OK, you've got this. =)

[@MaskofFayt]

This video is a life saver. I've got loads of that stuff laying around the house never thought to use it for seam filling.

[@punishedprops]

We're so glad it helped!

[@imdaveybuds]

damn as someone who worked in trades for years i never thought plastering would be something i would use in prop making thanks for the amazing video! love your books! you really have helped me out alot starting out as a cosplayer making armor this was super useful i thought my chest piece was toast till i discovered all your stuff!

[@punishedprops]

That's fantastic! =D

[@SuicideNeil]

4:20 "The bigger the gob, the better the job" - AVE.

[@punishedprops]

+SuicideNeil YES!

[@palsh]

Bill, thanks for all your help. This video helped me out a lot. I've been filling without using water to smooth out afterwards, so I'll be trying this next.

[@liamwarren3086]

This video is waaaay more in depth than Evil Ted's seam-filling video. Many thanks.

[@scp-09698]

So I bought that Foamsmithing Book from you guys and let me tell you, I am NO professional but HOLY, I swear it was like a 90% improvement on my patterns, cuts, glueing. Everything just looks so clean. It amazes me what you people teach!!!!!!!!!!!!!!!!!!!!!!

[@punishedprops]

+Charity Fleites That’s Splendid!

[@BoomTownTTV]

The I depth tutorial will really help me with my cosplay, thank you.

[@ian3314]

Thanks Bill and Brit, your videos are priceless. I just started building with foam and inevitably if I have a problem I type in KZbin the problem and punished props and you guys have a video about it. Can't thank ya enough!

[@punishedprops]

+ian3314 That's great! =)

[@StarsetFlight]

Your channel is by far my favorite channel for being informative, entertaining, and descriptive while displaying the desired information. Getting me hyped for this next cosplay!

[@punishedprops]

That's really great to hear, thanks so much!

[@StarsetFlight]

@@punishedprops hell yeah. Keep the great content comin! 🤘😄

[@marcdoland170]

Thanks, Bill! I'd asked about seams on your last Q&A and now this! Your answer was to just start over, so I did. My cuts on the second attempt were much improved. This is really helpful for those little, glaring parts. Between you and Evil Ted, someday I may be halfway decent at making things out of foam.

[@punishedprops]

+Marc Doland Super cool!

[@videoactif]

If you have access to a bandsaw, use it. It makes clean cut.

[@Tia_Mimis]

Thanks for all your videos, it has been very helpful.

[@MrSmokinjayes]

Thank you,..Ive been working on a foam armour & this is exactly what I needed to know to help clean it up .

[@punishedprops]

Fantastic! We're super happy to help :)

[@TheShozumi]

Saw you make this at SVCC. It was so cool. Thanks for answering the questions we had while you were building.

[@punishedprops]

You're most welcome! =D

[@Morna777]

Kwickseal doesn't seem to like acrylic paint much, I find a thin layer of a matte nail polish or topcoat helps.

[@GraceWillow]

I LOVE QUICK SEAL!!! Also this looks great

[@punishedprops]

+ZonZonZonbi Thank you!

[@superkalelman]

Awesome video. Thank you for sharing.

[@n3propmaking153]

Looks like a useful material, I'll have to use it in the future!

[@Shadicats]

Typo in the description: "Paterning a Foam Helmet" Patterning Thanks so much for this. I was trying to find a good way to fill in seams. BONDO made the helmet heavy. This seems like less work, faster, better, and less toxic.

[@punishedprops]

Good catch!

[@Shadicats]

Any chance at a free pattern swag as an reward?

[@tjruggiero5537]

Thank you Bill. You are a god among men

[@Dabura911]

I was looking for a good sealer for seams, thanks mate :)

[@punishedprops]

You're welcome!

[@rasmus2705]

This was actually VERY helpful ! Thanks

[@punishedprops]

You're welcome!

[@cosplayking5242]

best eva tutorials on youtube

[@sauronsrighthandman301]

Very nice video I will have to look into seam filler for some new additions to my foam halo armor. Personally I sand down the Seams of my armor to make them flush, with larger pieces like a rifle I use modeling clay from Italy. It has a bit of give to it but since it's I. Italian I have no idea if or when it expires.

[@neeneemartin5867]

What are the advantages to using Quickseal as opposed to something that can be sanded, like PlasticWood?

[@EightBitBella]

Do you have to seal the seams with a different sealant than what you use for the rest of your prop? Or would going over the whole thing in say PlasticDip work?

[@mexicansuperman123]

Oh looky, a paladin helmet from Voltron... I'm pretty stoked, not gonna lie. In the other videos i was looking to see how i could make it into a paladin helmet. And now this! You and the wifes videos ate always a treat. Now I'm gotta wait and see which paladin you're gonna do. Money is on Pidge, closest related to you guys imo. Close second is Keith, just 'cause bright red might catch your fancy.

[@punishedprops]

+mexicansuperman The build video for my paladin helmet will be on Tested's channel soon.

[@samdrummond9847]

I am loving your videos and patterns. I have printed out your Lego sword and shield pattern and I am having a go at making them with foam rubber. I will send you a picture or video of the finished product. It’s my first attempt at making anything, besides floor, with foam rubber. Keeping everything crossed I don’t hash it up!

[@punishedprops]

That's fantastic! Have fun :)

[@hasbi1300]

do you think fox glue can be used as an alternative seal ?

[@SionnachStudios]

I know of a pretty nice bayard that would go well with that paladin helmet ;) Does this mean you guys are doing full paladin armor builds?!

[@Fuzzyfire]

I cannot wait till my order of foam shows up...i want to create!!

[@Tia_Mimis]

Could I refill areas in my armor, even after it has been painted? Just wondering if it wouldn't stick do to the paint.???

[@owhiskers898]

Is the construction and installation of the paladin face shield in the future for this build? So many questions about how to do that.

[@punishedprops]

+O' Whiskers Yes indeed!

[@Geeksmithing]

Hey! I spotted my sticker! 😁😁😁 Thanks for the tutorial Bill, I am finally gonna give this stuff a shot!

[@punishedprops]

Hurray! =D

[@Geeksmithing]

@@punishedprops Mega Man X for my son's Halloween costume seems like a good place to start! 😆

[@Sierrebrarc]

Kwik Seal Plus, or can I use regular Kwik Seal? All I can find online indicates the only difference is the Plus has a better anti mold/fungal additive.

[@IdkMyDude]

Quick seal is great

[@LonelyWolfJ]

We don't have kwik seal here in our country so I am currious is it much different than windows seal caulk.. I've been using this for foam.

[@jackkuehneman9300]

hey Bill! wondering if you could do another mold making video but with plaster? Getting into mold making, it can be really expensive but plaster is a really cheap alternative, plus it's at most stores like Walmart and home depot etc. So maybe using plaster would be a learning tool before putting money into silicon. what do you think?

[@punishedprops]

A rigid material like plaster is useful for making molds for anything that will be cast in a flexible material. Most of what we do requires a flexible mold, like silicone.

[@charcoal386]

What is quick seal normally used on?

[@Raeinok]

is this post or pre sealing? can i go back an correct a seam after i used plasti dip on the foam?

[@DouggieDaDucker]

Can you still heat gun it afterwards or is that it?

[@jameseliot1134]

Kwik seal vs Kwik seal plus. Which do you prefer???

[@an7d7y]

Is quick seal able to flex or will it crack?

[@IrethOronar]

hey Bill! thank you for this video! I live in Italy, and I couldn't find Kwik seal anywhere :/ can you tell me what it basically is, so I could look for a valid alternative? is it some kind of quick drying silicon perhaps?

[@originaltrilogy1]

I'm still hoping someone will answer this

[@paulwegener7380]

Neat tip. I may have to make a helmet now :)

[@punishedprops]

Yeah you do! =D

[@dollmakershazbot900]

Awesome video, but I was wondering. After applying the Kwik Seal, I usually go straight to Plasti Dip 3 or so coats before paiting. Would you reccomend sealing with something else beforehand or it's acceptable as is ! Keep it up. your videos are super informative.

[@punishedprops]

We coated this helmet with Creature Cast after cleaning up our seams but PlastiDip works just as well. You probably can paint right over the Kwik Seal but having those extra few layers on top will definitely help your surface quality even more. - Paige

[@kshatriya1414]

Omg I so didn't understand that it was a voltron paladin helmet :D

[@SharkKid42]

Nice to know I'm not the only person who uses stuff like that to fill cracks and holes.

[@BadWolf666]

while you're im the helmet making mood you should make a boba fett helmet

[@skywardsaint1253]

Is it sandable? Making my sword prop smooth to paint is my number one priority

[@DarthLeefer]

does Plasti-dip cause the kwik-seal to shrink? i thought my seams were all filled correctly but as soon as i put a coat of plasti-dip on the seam i was trying to repair pulled away from the edges and opened back up just as bad as it was before. i let the kwik-seal cure for about 20 hours, i thought that was good enough, but its the only other thing i could imagine caused it

[@ancatdubh43]

I happened to watch this for fun the night before my cat gouged a divot out of some armor I'm working on, so this is a lifesaver! I'm assuming it's still ok to do this after plastidip has been applied and then spraying another coat?

[@punishedprops]

+Andrea Michaud That would probably work.

[@kayteekc]

hi I am wondering if after sealing it and wanting to paint it does Mod Podge work?

[@punishedprops]

+Kaytee Kc Sure!

[@arklanuthoslin]

so, something about EVA foam armor i've been wondering - is it good practice to keep it flexible, including seams and putty and such? i ask as a big fan of Apoxie Sculpt, which gets rock hard.

[@punishedprops]

I prefer to keep my EVA foam builds flexible.

[@TheRogueCosplayer]

Can you suggest and alternate product to do this for people with allergies to latex...?

[@punishedprops]

Hmmm I am not sure as I've primarily only used this product. But if you look for a silicone-based caulk/adhesive you should be fine

[@aj.taulbee]

I really like this general helm layout but they seem to bow out too much around the bottom. Do you think bending them in and heatgunning them for a bit could fix that?

[@punishedprops]

+Anthony Taulbee Sure!

[@MalinOfSweden]

Is Quick seal acrylic based?

[@punishedprops]

+Mats Larsson It might be.

[@billghli]

Does anyone know if you can use cut up paper and pva/woodglue to fill seams in foam? I know Dali-Lomo uses it for paper helmets/props but I was wondering if anyone knows of it working for foam helmets, I plan on using PVA for a sealer too before painting. Might work better if it's all done with PVA glue so I was wondering if anyone had tried it, if not I guess I'll try on some scraps. Any info would be much appreciated!

[@gayemarianesfox2405]

My daughter is making things with foam and has been a little sloppy with the hot glue. Any tips for her to get it off?

[@muffyy01]

Does regular glue work too I don't have access to this stuff

[@codynewcomb3819]

Could kwik seal be used,in Lou of bondo? I bought a helmet from a prop builder that needs love

[@punishedprops]

If the helmet you bought is a rigid material, I would go with Bondo so that it can be sanded smooth.

[@epiendless1128]

Can you glue stuff on top of the sealant? I used anoither brand of sealant, then found contact adhestive wouldn't stick to it. Update: I got some Kwik Seal even though Amazon had to import it, and yeah, it's a LOT better than generic sealant from B&Q.

[@EricFaries]

Ok is there like a special putty or cure time? Cause i literally used Kwik Seal, the same kinda from what i read on your container, and it's just not working. It's not sandable at all, it just peals off like dead skin after sun burn. I even let it sit overnight. Could i just use foam clay to fill gaps? Sorry if i sound agitated, i've been trying my best to follow these guides and tricks and being careful but my foam mask just looks so bad. Even sanding the foam it just sorta leaves fibrous texture that even when i try to use heat to smooth out doesn't help. I'm trying to hard to do everything right but getting bad results. :(

[@punishedprops]

No worries! You may be using sandpaper that is a little too rough, so it's worth trying something a bit higher in grit.

[@EricFaries]

@@punishedprops Thanks for the reply! I watched more of your vids, or was it Evil Teds...anyway, in one it was specifically mentioned that Kwik Seal is not very sandable, sooooooo my bad XD I managed to get my mask finished following more of ya'lls videos and Ted's and it came out great! Should look good while up on stage playing loud music XD

[@ivor00]

cool but i am interested if there is a product the same thats available in Australia. does any one know of anything

[@liamwarren3086]

Kwik seal is great and pretty flexible, but spackling paste (also from dap) is sandable, so you can fix inconsistencies.

[@liamwarren3086]

If you mess up in the process

[@punishedprops]

I tend to err on the side of flexibility for my foam armor costumes.

[@c3diy]

Can you add heat sealing+ normal primer on using this?

[@punishedprops]

Sure. I'm going to seal mine with neoprene first.

[@c3diy]

Cool thanks alot!

[@danielospino3727]

I have a bad glue on a seem, (only 6th build) but I see it didn't stick well. How do you suggest fixing it?

[@punishedprops]

The main things I seem to encounter messing up seams is too much or too little adhesive, so it might be worth testing that.

[@BoomTownTTV]

Great video, where do you get that jacket from?

[@punishedprops]

The Bungie store had them for a while.

[@BoomTownTTV]

Punished Props, thanks for the info. If they make a new one for D2 then I might pick it up.

[@gregorthegregorian9155]

I've attempted this in the past with mix results. Sometimes I see the quick seal pulling away as it dries leaving the gaps there. recommendations?

[@punishedprops]

+Gregor The Gregorian Don't let it dry, work in small batches.

[@gregorthegregorian9155]

Thank you sir. Might have misstated the issue. Apply in small batches but as it dries/sets the quick seal shrinks somewhat, leaving gaps again. Maybe I am applying too much at once. I shall refine and move forward. Thank you sir.

[@xanderwallace9522]

Could you use flexseal

[@punishedprops]

That might work, but we haven't tried it ourselves yet.

[@theused0179]

Please tell me you're making a full paladin costume. I'm working on a Zarkon cosplay for dragon con. Would love to get pics with you.

[@punishedprops]

+Motive Props Right now I'm planning on just the helmet.

[@ape566]

Could I use the white Kwik seal ver? It's the only one I've got

[@punishedprops]

White Kwik seal is what we used for this video

[@R83TV]

Is it acrylic? Trying to figure out what yo buy. On a different country and don't have the product you are using

[@punishedprops]

Sorry I'm not exactly sure.

[@chubbchubbs620]

I was wondering can i use Wood Glue for filling in seams?

[@punishedprops]

Hmmm that's a great question! I haven't tried using wood glue on foam for anything beyond sealing. It could potentially work, since wood glue is somewhat flexible, but it might be hard to get the surface smooth, since wood glue requires sanding and is harder than foam.

[@apony6263]

when you can't catch any of the streams because of school... rip. is there any way i can access them at a later time?

[@marcdoland170]

The full stream should be available on twitch.tv. I was watching it last evening since the stream always happens while I'm at work.

[@alexmazurek18]

Do you find that the quick seal paints/finishes differently? I recently patched a few seams with some spot putty and when I painted the piece, those areas stuck out like a sore thumb.

[@punishedprops]

I do a few coats of primer or PlastiDip over the surface before painting

[@alexmazurek18]

Noted. Thanks!

[@ZynthCode]

What, exactly, is "Creature cast", and where to get it?

[@dillonhunt1743]

does creature cast dry smooth when brushed on?

[@punishedprops]

+Dillon Hunt We will find out soon.

[@bummer6]

I usually sand my foam and fill it with latex caulk. I wish I could get perfectly clean seams like Bill does. >:C

[@rjwohlman]

Does this work on all types of foam including phone that is Ridgid?

[@punishedprops]

No, rigid insulation foam reacts to materials differently than EVA foam

[@aeonsword]

one question im from chile and i have no idea if Kwik Seal exist in my country with anoter name you can sand it?? is not silicon right?

[@punishedprops]

You can sand it a little bit. Sorry I don't know what it would be called in your country.

[@REACH_khbk]

Does this work with craft foam also? Making my son a costume, and some of my seams are... eek! Being able to fill and smooth them would be REALLY helpful. Can Kwik Seal also salvage that sort of thing? And if so, before or after diluted glue coats?

[@punishedprops]

+Katrina K Yup! Craft foam is the same as EVA foam.

[@REACH_khbk]

Thanks!!

[@coalakida]

How can you hide a seam of two pieces of EVA foam doubled up without having to prime and paint it. is there any other way to do it ?

[@punishedprops]

If you can sand that seam flush on something like a belt sander, that would do it.

[@reyrobles1323]

Newbie question. Do you do this before you use plastidip?or after? Thanks.

[@punishedprops]

+Rey Robles I would do it before.

[@mints3450]

are there any kwik seal alternatives?

[@punishedprops]

I'm sure there are, I just don't know what they would be called, sorry!

[@patrikarte]

Hi Bill. Here in Europe we can not find this product. Do you know any analog one that can be bought here and do the same work? Thanks

[@punishedprops]

I'm sorry I do not.

[@aumannm6587]

A latex caulk is what you are looking for. It can be painted, and is still flexible for your props.

[@ArtSurvivesArtist]

What do you do when the Dap peels right off once it's dry. I tried several times and every time it didn't stick. Also, not a advertisement for the bathroom/kitchen application, I guess.

[@punishedprops]

It's important that you use the Kwik Seal specifically and not a different DAP product. The dry product won't adhere to the foam. If your Kwik seal isn't working it might be because of the type of foam you're using, or maybe temperature. I'm not sure

[@charlesrestivo870]

What color does it dry

[@punishedprops]

White!

[@demondragoncosplay3615]

will this work on bigger seams? cause the contact cement I have to use isn't the best so it leaves big gaps and seams.

[@punishedprops]

Depends on the width of your gaps. I'm not quite sure what the limit is.

[@demondragoncosplay3615]

thank you for your help

[@beatlebeat3419]

👌

[@hendrasb5963]

What fuction of the water? Tks

[@punishedprops]

The water helps thin the Kwik Seal and makes it more smooth, like smoothing clay.

[@maube8007]

I don't like to use Quck Seal or caulking because paint and primer don't stick to it. Is there an alternative that is sandable and not waterproof?

[@punishedprops]

Hmm, I haven't ever had that issue. Foam clay might be a good option for you!

[@maube8007]

@@punishedprops Thanks I'll look. Been reading up, some say paint is more likely to stick to acrylic based caulking. There's also something called Rapid Fill that people seem to like. May I ask what that green stuff you were filling seams with in the Mandalorian Helmet video is?

[@oliviamah4908]

Does the kwic seal plus crack?

[@punishedprops]

Nope, it stays pretty flexible.

[@Randomd0g]

Would wood fill work as well? For a less flexible piece at least

[@punishedprops]

It might, but I wouldn't use it on EVA foam.

[@Randomd0g]

Aw, I have some wood fill I need to use up. Guess I could experiment and see how well it holds up on some scrap lol Thank you for responding!

[@ravonos]

With small seams like those would plastidip fill those in after a few coats?

[@punishedprops]

+Ryan McQuilkin Probably not.

[@liamwarren3086]

Ryan McQuilkin Plasti dip is REALLY thin, and it soaks into the pores, so it will actually bring out flaws on the surface. The texture has to be perfect before you seal it with plasti dip. Others, like mod podge and some latex, are thick enough to create a new texture on which to paint.

[@idrawbadly1015]

Does this stuff dry hard like bondo or soft and elastic like silicone?

[@punishedprops]

It's silicone-based so it's more flexible but less stretchy.

[@idrawbadly1015]

@@punishedprops Thanks for the reply! That's what I need. I'm doing my first ever cosplay build - Fallout power armor helmet - and I could drive a truck through the glue seams so I have some filling and fixing to do. Got another question. The shape of one of the pieces I clued up didn't come out quite the way I intended. Is it still possible to go at it with the head gun and adjust the shape or would that melt the contact cement and make the seams come undone? Thanks! Love your channel!

[@HorseHead1969]

Chowdery!!

[@moosefarms]

Where do you prefer to buy your EVA foam? I bought 36 2'x2' tiles on Amazon for $80, but the quality was a bit so-so. I could see a noticeable difference in thickness between some of the tiles and there were a lot of large air bubbles on the smooth side of each tile - which lead to more Kwik-seal work. I want to save money, but I also want to avoid unnecessary clean-up later.

[@punishedprops]

We like tntcosplaysupply.com

[@moosefarms]

Thanks! Oh, I've been there before! I'll definitely give them a try. Side note, a friend just gave me your book that I've been meaning to buy. Pretty excited!

[@Dami_Ka]

Super late to the party here, but if you have a Lowes hardware store in your area, they usually sell EVA floor mats there.