How to Make A Fiberglass Mold from a Plug - Part 1 

Fantastic video. Thanks, Stephan! For all those asking about the foam, Stephan clearly states that it's EPS (expanded polystyrene). I'm not sure if XPS (extruded polystyrene) would work the same. You can find pink Corning EPS in different thicknesses in the insulation aisle of Home Depot. At Lowes its colored green or blue. Glidden "gripper" primer paint works well to bond EPS. It's cheaper, more forgiving when lining the parts up, easier to clean up, and the fumes won't scramble your brains. Lots of videos on YT about cutting ad shaping and gluing EPS. EPS is really popular with RC drones builders and Halloween tombstones artists. Check out their vids, too. Great suggestions in other comments about using a template on both sides of the plug and letting gravity do the work. Also an excellent suggestion to use a spring to keep tension on the wire. The suggestions to put the wire cutter in a vise and working the plug around it works okay with small pieces. But it's quite awkward with something this large. At least it is in my uncoordinated ants :-) Thanks to all for the input and questions. This is what community thinking is all about.

Be sure to use Polystyrene foam when using a hot-wire cutter. If you cut Urethane foam (from craft store) with a hot-wire, burning urethane creates Cyanide gas, which is deadly. Good video!

Спасибо тебе добрый человек)!

You are doing it wrong. Use template on both sides and let the gravity cut your hot wire cutter thru the foam. Will get perfect clean surface and that that jaggy potato ;)

I understand it's pink panther foam just curious does,it matter if its,formula 250 or 150 r5 r2 I know there are diffrent types I'm just wondering will this change the results of making a mold this exact way you do this in all 4 videos cause I hear somevresin melts foam

I used to cut model airplane wings, I put copper foil tape (the kind used on stained glass) to keep the wire from hanging up on the wood templates.

Put aluminum tape over the pink, then one layer of fiberglass over it, let harden and fill in perfections with body filler pull a plug from that

Done this b/4 back when kevlar first hit composite supply shops. Point plotted my own design racing canoe in sucessive stacked layers glued to each other layed out on a 30ft. weld/fitters ground flat precision slab. Sanded the foam steps between layers then used epoxy and kevlar inside an out. Ther are many ways to make molds and good old Home Depo foam works!

I tune my cutter to an 'E' but a D still works. Does anyone have the TAB for this? But seriously... Lovely work, BRAVO I am going to now re-purpose all my old insulation off-cuts.

hey, I really like your demonstration. What kind of glue do you use to glue the pink foam together?

(facepalm) I've used pink (ore Lowe's green) foam and hot wire to make R/C planes for years. I was looking at my bike last weekend and thinking, " I want to make a cafe racer seat, but there's no way I'm buying sheetmetal tools just for that." GREAT IDEA.

Hey bud, great idea and video. For better control make the cutter stationary using a bench vice and work the form around the blade.

If you put spring on one side of hotwire it will automatically stretch the wire and save you some nerves ;). i work with hotwire cutter every day and that simple mod helped a lot.

Thanks, love the videos!

This video was worth watching for the hot wire tension tip alone. Brilliant

I've made several hot-wire foam cutters and even owned a CNC hot-wire cutter, but I never thought of using a guitar tuner for tensioning the wire. I always used a spring at one end to keep the tension as the wire heats up (a must-have IMO) but getting the tension just right was a pain. Using both a spring and the tuner would be perfect.

Best Video about models Resine show

Could have attached a small bubble level on the cutter to give you a better idea of level. Maybe it wouldn’t have helped much but this was very helpful for me. Thank you good sir

What "KIND" of wire did you use? A guitar string? 316 steel or resistance wire?

It will work with several D cell batteries too. Harbor freight sells (or did) one of these that is on a much smaller scale with a 6 inch wire cutter. In fact it looks like a coping saw which would be a good tool to repurpose. Hmmm.

youtube put you thru 45 sec on adds to see this video.

Hello i am making a plug from clay (Plasticine) as it is easier to work with for the project i am doing , i am wondering what you would recommend to seal the clay to prevent it from affecting the gel coat or resin.

What kind of foam is that? You use the brand name (Pink Panther insulation foam) but I'm in UK and we don;t get that here. Is it polystyrene or polyurethane or what? Once I know the material, I can find some. Thanks.

What aerosol glue is that? I tried the 3m headliner adhesive and it melted my foam board (i had the green version of that stuff.

What kind of glue did you use to glue the foams together?

I use an old electric carving knife. No toxic fumes to inhale; no fire/burn hazard to be wary of.

Easiest DIY Foam cutter here. Nice Job

What glue do you use, I use liquid nails and it does not to form well. Thanks

Hey fren. Did you just use copper wire for both the anode and the cathode on the battery charger? Or do you have to use a different type of wire for the cathode?

hallo there something i would like to ask you if you know if its possible i am making a sculpture from clay only and the clay i use a lot of is air drying clay and i want to learn how to use fiberglass but i dont know if i can make a plug from my clay master first do you think it is possible for me to make a plug from my clay statue i will be making in the next few days ok

Is this material used to build a mold for a fiberglass tub? Thanks.

Definitely using this on my 62 lone star👍🚢 SUBD

If you had two templates to sandwich the foam ..?

That Pink Panther Foam smoke is really healthy??

What gauge of ni-chrome wire did you use? Do you answer questions?

Never know which "part" to leave my comment(s) in :P THANK YOU very very much for this lil "making molds from plugs" series, I got my 1st bondo/polyester-resins and fiberglass-resins (both, using poly as 'structure' with waterproof fiberglass-resin outers, when making small pieces) earlier **this month** so am very very green here but thanks to youtubes like yours here I have learned SO much so quickly and am having a blast with it, however I didn't know if I could 'get away' with using foam as a structure for detailed, small-size, 1-off creations (am not even using it 'as a plug' as you're detailing here, the foam will just stay in-place and be 'skeleton' because the piece I'm making can-be, in fact *is better-as*, a hollow piece instead of me trying to free-form mold Bondo and then glass over that which is what my method *would've* been if I didn't think "....go check youtube 1st" lol, and this was the 1st vid --- I love the web&video-sharing but gotta say this is a great example of *why* I mean I didn't have to go to other youtubers' takes on the same thing just your vid (well, vidS, since you split it up -- going for higher #'s that way I presume? naughty! ;) ) and am now ready to go outside and work instead of watching more vids / googling more!) Thanks again, kickass video @TotalBoat am gonna 'scribe even though I probably don't need more glassing-instruction at this point (hmm maybe you have carbon-fiber work, that is my next 'venture' here!)

spray 3M adhesive lightly so as not to melt the foam

I've used the "G" string (from guitar) for best results, however, you want the lowest setting on your charger or it will quickly melt your wire ......it gets red hot and breaks apart. Or maybe a supply with multiple amp knob to adjust it perfectly .....maybe a model train power supply ? ? Anyone know ? Thanks.

great video

Turn power up...Not enough smoke Inhale for long life

Holy shit this is EXACTLY what I was looking for! Thank you!

Can u make a video on ,,how to make FRP Lip ?

Awesome video, I might use this method as we build our FSAE car next year!

Best cutting foam technique 👌

What kind of adhesive do you use for gluing the foam boards together?

Put a small level on the handle will help.

Can you make a vid on how to make the cutter??

Best solution frend ❤❤❤❤

whats it is name for this material

Good

Where to buy this foam

Thanks for the great, informative video!! Sir doe's this not burn the battery charger up or cause any problems with it? Also what do you set the charger on? Thank You!!!...

what glue did you use?

I thought when you glue foam together the spray adhesive would melt it.

Can i use epoxy resin for fibreglass mat..?

What type of glue did you use to bond the foam boards together. ..thanks

what foam you use?? XPS or EPP foam??

Can u plz tell us where u but this foam and how much it cost?

How to make a plug for a full size car?

I can smell the plastic smoke from here!

Where did you get that insulation foam?

Where did you buy the foam from?

Cutter is awesome..

Hello What material is the pink insulation? Styrofoam? Thank you in advance

can you give the link of the foam you are using?

I wanna make custom louvers for my rear side windows like the Mustangs have nut for my 1975 nova how would I go about doing this

Amazing guidelines... thanku

May I know what is the name of the foam you used? Thank you!

That was so satisfying to watch !!!

why type of foam is this??

Which foam have you used in this model?

what kind of wire do you use?

Can i use clay as an alternative to the foam for molding?

What did you used to glue the foam layers together and does it effect the cutting with wire ?!

This pink material is a styrofoam or foam ?

Awesome, I was planning on doing the same thing for my body fenders

Fricken love this video!! Thanks

super!

This guy needs to calm the hell down!

Nice!!!!

Protip on the cutter...its easier to put the hotknife in a vise and move the part.

Really helpful vid

is that epoxy for a boat used ??

That was a Great Presentation! It was Clear & Short! Those two aspects are Very Valuable!

Yooooo!!!!!! This is the best idea ever!!!!!!!

this was great! thank you!

Yeah... I'm going to be a critic and say that pink insulation foam is a crappy material to work with. The solvents and catalysts used in most fiberglass resin/gelcoats react with the pink foam, hot glue melts the foam, body filler does not stick to the stuff at all... Frankly it was a pretty bad suggestion. Just use clay and/or cardboard, then use body filler. It will save everyone the trouble.