See full version: How much epoxy does it take to fill fiberglass cloth
Some epoxy create a water soluble blush after hardening. This somewhat waxy coating needs to be washed or sanded off before re-coating if you have waited for more than a few hours. Barely set epoxy can be re-coated without removing amine blush. [links]
Blushing epoxy are just as strong as non blushing types. You just have to remember to remove the blush. [links]
Once the glass has been properly coated with epoxy it is fine to sand the surface. IF you have not filled the weave enough and you sand, you risk cutting the higher threads of the weave seriously weakening your glassed surface. [links]
I was running out of epoxy resin and wanted to know if I needed to get more or if I had enough. This is what I found out.
A more accurate range would be 2 or 3, to 1 depending on how you apply the resin and on how thick your laminate is. Several layers of cloth will take up more resin than just one layer. On the other hand, carefully squeegeed coats of resin can fill the cloth with only 2 to 1 ratio. more
This is a quicker method and is a great option when time is an issue. [links]
First, pour your initial coat of epoxy resin and wait 24 hours until the resin has cured. At this point, it will no longer feel sticky: it will feel smooth and dry to the touch so you'll need to rough up the surface with coarse sandpaper to create some tooth for the second coat. After you've wiped away the sanding debris, pour the next coat overtop.
💡TIP: Remember: whenever your resin is dry, you need to sand before you apply a second coat to ensure the two layers bond together. If you don't sand, you run the risk of the two layers eventually delaminating. Use a coarse sandpaper to really rough up the dried resin surface - we use an 80 grit sandpaper here at ArtResin. Don't worry - once you pour on your fresh resin layer, the scratch marks from sanding will disappear. [links]
After you’ve applied your first coat of ArtResin, wait about 3-5 hours until it starts to thicken and reaches a gel like state. At this point, you can pour the next coat on top. T he stickiness of the resin will provide the tooth and the two layers will cure simultaneously, creating a very strong bond.
💡TIP: If your resin room is warm, you may be able to pour your next coat of ArtResin at the 2-3 hour mark. [links]
As long as you pour in 1/8" layers, you can get as thick an ArtResin coat as you'd like. There are two methods for applying additional epoxy resin coats: sanding down your first layer after having let it dry for 24 hrs or, if you're in a hurry, you can pour a new resin layer every 3-5 hrs. Either of these methods work very well, allowing for a very strong bond between resin layers.
Let's take a closer look at each method: more
To calculate the number of layers of fiberglass cloth needed to build a specific laminate thickness, divide the desired thickness by the thickness of a single layer of the type of fiberglass fabric you want to use. here
There are several different types of fiberglass cloth available, such as woven, biaxial, etc. In the United States, fiberglass cloth is specified by its weight per square yard. For example, 6 oz. fiberglass cloth weighs 6 oz. per square yard. In addition, each fabric weight will have a different thickness. Some of the more common types of fiberglass cloth are shown in the table below.
The examples below indicate how much biaxial fiberglass cloth is needed to build a 1/4" thickness of glass. Note that biaxial cloth or biax is available with or without mat backing, and each type has a different weight.
That can work very well and is the quickest way to do it, too, but there is risk of bubbles forming. I've had it happen when the wood underneath outgassed and the gas was trapped as bubbles between the layers of glass. Fortunately I noticed this happening before the epoxy had finished curing and was able to work the bubbles out. here
RE: Multiple layers of fiberglass cloth
RE: Multiple layers of fiberglass cloth
Stack everything up and epoxy it all at once.
If you are going to use multiple layers of fiberglass cloth, is better to let the first layer cure before adding the second layer of cloth, or can you apply resin to the first layer, then put the second layer of cloth over the first layer and let them both cure together? My goal is to minimize the chance of bubbles between the layers.