Fiber glass

[Franklin]

Materials you need:


A mold, I used MDF but it’s possible to use many different materials like glass, clay and even polyester. The smoother the surface is the better it works. Some materials, like MDF, will have to be coated with a polyurethane resin to seal the pores of the material.
http://fjw-modding.nl/afbeeldingen/polyestertutorial/puhars1.jpg
Synthetic resin.
http://fjw-modding.nl/afbeeldingen/polyestertutorial/hars2.jpg
Catalyst.
http://fjw-modding.nl/afbeeldingen/polyestertutorial/harder3.jpg
Release agent.
http://fjw-modding.nl/afbeeldingen/polyestertutorial/was4.jpg
Surface tissue.
Glass fabric. There a many different types of glass fabric, just ask your supplier what is best for your job. Some fabrics are more suited for difficult shapes than others.
Cleaning fluid, to remove the release agent before painting the fiber glass.
Polyester filler, to fill up any imperfections.
Scissors, to shape the glass fabric.
Putty-knife, to apply the polyester filler onto the fiber glass part you’ve made.
Industrial mask, sanding the polyester gives a very nasty dust that is dangerous for your health!
http://fjw-modding.nl/afbeeldingen/polyestertutorial/masker5.jpg
Brush, not a soft one. To apply the resin.
http://fjw-modding.nl/afbeeldingen/polyestertutorial/kwast6.jpg
A measuring beaker
http://fjw-modding.nl/afbeeldingen/polyestertutorial/maatbeker7.jpg
Sanding paper grid 1200
Roller, to remove bubbles of air.
http://fjw-modding.nl/afbeeldingen/polyestertutorial/rollers8.jpg
Hypodermic syringe
http://fjw-modding.nl/afbeeldingen/polyestertutorial/spuit9.jpg
Latex gloves
http://fjw-modding.nl/afbeeldingen/polyestertutorial/handschoenen1_0.jpg


Step one: Preparing your mold

Apply release agent, I used mold release wax, onto the mold with a cloth.

http://fjw-modding.nl/afbeeldingen/polyestertutorial/was4.jpg

Leave it on for a couple of minutes and wipe it off in a circular motion with a clean cloth. Repeat this step about three times. This step is very important, because you don’t want the polyester to stick to your mold.

Step two: mixing the resin with the catalyst

Pour the resin in a beaker or jug.

http://fjw-modding.nl/afbeeldingen/polyestertutorial/inschenken1_1.jpg

Add ~1-3 % catalyst to the resin, use a hypodermic syringe to add the right amount of catalyst.

http://fjw-modding.nl/afbeeldingen/polyestertutorial/afmeten1_2.jpg

While adding the catalyst, stir the resin.

http://fjw-modding.nl/afbeeldingen/polyestertutorial/roeren1_3.jpg

BE WARE the catalyst is very corrosive and oxidizing so wear latex gloves!

http://fjw-modding.nl/afbeeldingen/polyestertutorial/mek1_4.jpg

Stir the resin about two to three minutes. This is very important for the process. The color of the resin changes from blue to yellow/brown.

Step three: applying glass fabric and resin to your mold

Use a brush to apply a thin layer of resin to your mold

http://fjw-modding.nl/afbeeldingen/polyestertutorial/instrijken1_5.jpg

Put a layer of surface tissue on the mold. Tap with your brush onto the fabric. You can see the resin come through the fabric.

http://fjw-modding.nl/afbeeldingen/polyestertutorial/insmeren1_6.jpg

Add some more resin with the brush if necessary. The resin should be visible all over the fabric.

http://fjw-modding.nl/afbeeldingen/polyestertutorial/uitrollen1_7.jpg

Sometimes bubbles of air get stuck underneath the fabric, use a roller to remove the air.

http://fjw-modding.nl/afbeeldingen/polyestertutorial/rollers8.jpg

When the resin covers the whole surface of the fabric, add a layer of glass fabric and repeat the previous procedure. The more layers of fabric you add. The thicker the polyester gets and the stronger and more rigid it gets. I used about three to four layers of glass fabric and one layer of surface tissue.

Don’t rush things, but you have to know the resin starts setting in about 10 to 15 minutes, depends on how much catalyst you have used, so make sure you are finished with a layer within that time. You can always add one or more layers if you need to, later on. Just wait a couple of hours, mix some new resin and start the process over for the new layer(s) you want to add.

Wait about one to two hours and cautiously remove the polyester from the mold. You can pull and push to get the polyester from the mold. Just take your time and don’t try to get it off by just pulling in one spot. Pull at several spots/areas to distribute the force evenly. It’s easy to see where the polyester releases from the mold. I found it easier to remove the polyester before it was completely cured. Now you will have to remove the glass fabric that sticks out.

http://fjw-modding.nl/afbeeldingen/polyestertutorial/rand1_8.jpg

Just use a saw or your Dremel to remove it and wear your industrial mask! And wear your latex gloves as well, because the dust is very itchy and dangerous. I found it out the hard way.

http://fjw-modding.nl/afbeeldingen/polyestertutorial/afzagen1_9.jpg

Step four: fixing any imperfections

Before giving the part a paintjob you will have to apply some bondo for polyester. It’s a paste. It comes with its own catalyst, also a paste. Add about 2% catalyst. Mix small amounts of bondo, because it cures very fast and use a putty knife to apply it. You only need to apply a very thin layer of this bondo. To get smooth finish wet sand the part with sandpaper, I used 1200 grit. Use water with some normal dishwashing detergent to get the best result. Everything smooth? Now wait some days for the polyester to get dry before painting it.

Step five: paintjob

It’s time to give the part a paintjob, but not before you cleaned the part with some cleaning fluid. This cleaning fluid will remove all of the release agent. Ask your paint supplier what paint is suitable for polyester, not every kind of paint can be used on polyester.

This tutorial will be improved as soon as I have some more and better pics.

[jdbnsn]

Awesome tutorial! Thanks Franklin!

[DETN8R]

for anything Corrosive I would have to recommend nitrile gloves. Great article BTW.

[Indybird]

Wait I didn't see where it got that round shape...
Also, would you recommend using Fiber-glass/this technique for making parts with somewhat complicated curves and shapes?

-Indybird

[jdbnsn]

He gets those shapes by making the object (usually out of wood) and draping the fabric over it, then coating it with resin. Check out his Evolutionary worklog in the featured section.

[D1337]

Could you take an object, paper mache it, then use this technique? Because i want to get the shape of an object i have, but not ruin the object in the process..

Or would it eat through the paper mache?

[Commando]

Awesome tut. Thanks. I love fiberglass. Messy as could be but really cool results.

+rep