Starting supplies for casting a hold
We're so close!
It's time to begin the final stages of creating a homemade climbing hold. In the photo above, you can see the supplies you'll need (minus the sand). You can find the fiberglass resin at any hardware store. It is a liquid that when mixed with the fixer (included with the resin) hardens. It is typically used in boat or car body repair in layers on top of fiberglass sheets. The can above cost us 36 dollars and cast about 30 holds. Of course your mileage will differ based on the size of your holds.
Next to the resin we have acrylic paint. This is one method of adding color to the holds. Another way is by using dyed sand.
Adding about a teaspoon of acrylic paint will give you some pretty good color. We have found that different colors have different drying times. So when using mixed colors- better just leave it to set for extra long to be safe.
For a more vibrant color, you can use dyed sand. This is usually finer and we like the finish of these holds better. It is more costly. A bag of colored sand (found at a hobby store) will be about 5 bucks for a pound. The other fine silica sand we have used on the majority of our holds was 6 bucks for 80 pounds. We have not been able to find white fine grade silica sand locally. This is used in pool filtration systems and may be the best option.
We have also had success adding glitter to make "fancy" holds. Pretty!
Which ever sand you are using get about 2.5oz in a 5oz Dixie cup. You can measure how much sand a hold will need by filling the mold with sand and then pouring it into the cups. If you follow this method you will end up with a little too much (because of the added volume of resin). You can sort of cheat the amount down maybe 20%. None of this is an exact science, so don't sweat over the measurements. We typically have extra small foot holds that we use any left over mixture in so we don't waste it. Hopefully our pictures will help.
Now you can add the resin into the cup. We try to add 50:50 sand and resin. We use the artwork on the cups as measurements to stay consistent from cup to cup.
Note: the sand is actually not giving the hold its texture. It is merely a filler for the resin.This saves on the cost of resin and can give color if dyed.
