Climb Hold Cost Breakdown
The specific cost to manufacture a hold depends greatly on the size, design, and volume of the hold itself. But we can get a very good estimate off of using the following calculations.
Lets start, take a medium sized hold that is approximately 3”x3”x1.5” that requires 7 fluid oz. For starters we need to calculate the amount of silicone rubber the hold will require. An ideal rubber mold will use as little silicone as possible. Using Dow Corning’s high tear strength silicone rubber (HS II or III – the III is just a little softer than the II which is a little better for removing extreme undercuts or negative drafts designed in your holds), you can get away with only ¼” wall thickness which will reduce the amount of rubber needed in making your mold. So if we add ¼” to each side of the hold and say ½” to the top to include a little as a fudge factor we will get a good idea of how much rubber will be required. So our mold box dimensions will be 3.5”x3.5”x2” deep. We then calculate the volume of this box and subtract the volume of our hold we will determine the amount of rubber needed to make the mold. So the mold box requires 24.5 cubic inches and the rock is 13.5 cubic inches. When you subtract the two you come up with 11 cubic inches of volume the rubber will need to fill.
So if our rubber required to make the mold is 11 cubic inches and the hold requires 7 oz, we can now begin calculating a close cost estimate for the hold.
There are 21 cubic inches per 1 lb of silicone rubber. So if we need 11 cubic inches of rubber we simply divide 11/21 to come up with .53 lbs of rubber. If we take a gallon kit price for the HS II of $165.00 for 10 lbs we come up with a cost per lb of $16.50. This is kind of a worse case scenario for many climbing hold manufacturers because the economy of scale is not with you purchasing only one 10 lb kit vs the 50 lb (5 gallon) or drum quantities but from this example you should learn how to calculate your cost per hold. So we then take $16.50 x .53 to calculate our mold cost of $8.75. If this mold yields 100 holds out of it before breaking down, you then need to divide the $8.75 cost by hundred to know the mold cost per hold. In this example it would be $0.0875 or basically 9 cents per hold you remove from the mold.
Now let’s calculate the resin cost per hold. A gallon kit of RC-3 (gallon of each side of our preferred rock climbing hold resin: 128 oz of A + 128 oz of B = 256 total oz) costs $90.00. Once again this is a worse case scenario because your economy of scale or price per gallon drops dramatically when purchasing larger 5 gallon kit and drum kit quantities but you will learn the process for accurately estimating your cost per hold. The cost per oz would then be $90.00/256 oz which equals .35 cents/oz. We then multiply that .35 cents by 7 oz required to fill the mold cavity (your hold) to come to a $2.45 total cost for the resin.
We then add the mold cost per hold of 9 cents to the $2.45 resin cost to come to a $2.54 per hold cost for a medium sized 7 oz shape.
Other cost factors that have not been included that will add to the cost per hold. Mold box materials, glue/clay for sealing the mold box down, foam to make the original shape/hold, dye if you choose to color it, washers, mold release to help extend your mold life (help make sure you get to a 100 pulls), and labor. All of these should be factored in to give you a more realistic idea of where your real cost per hold stands.
Mold box material is typically very inexpensive but should be factored into the equation. I personally recommend purchasing 4’x8’ sheets of corrugated plastics which you can cut to make quick and easy mold boxes with. It typically runs about $10 per sheet and will make a ton of mold boxes and bases. It can be cut or scored using a simple Exact-O type knife.
My other preference is to use hot melt glue to seal and bond the mold box walls to the base. Hot melt is an easy answer to making mold boxes very quickly. Inexpensive hot melt guns and glue sticks are found at a local craft store. Larger industrial sticks can be found online.
Our reactive dyes (meaning they actually chemically crosslink with the resin and will never bleed out) are very concentrated. To effectively color the resin you will only need approximately 6 oz per 5 gallon kit of RC-3 (preferred resin for making holds) which costs $19.20. 10 gallons of colored resin will make approximately 182, 7 oz holds. If you divide the $19.20 (cost of the 6 oz dye) by 182 you come up with a dye cost of $0.11. Add this $.11 dye cost to your $2.54 mold and resin cost and your new colored hold cost is $2.65.
Using a filler can dramatically decrease the cost of your holds. Using either dry playground sand, microballoons, calcium carbonate, or any other dry filler will reduce the cost per hold of your raw materials because it requires less resin and replaces that volume with a less expensive filler. Lets take a microballoons as our example. 5 lbs of microballoons costs $22.50. 5 lbs of microballoons is approximately 3 gallons of volume. To calculate a cost per oz of microballoons we take 3 gallons times 128 oz per gallon to get 384 oz. We now take our cost of $22.50/384 oz to come up with a cost of $0.06 per oz of microballoons which is much less expensive than our $0.35 cost per oz of resin. Now to fill that 7 oz of volume we can use 5 oz of resin and approximately 3 oz of microballoons to yield us a total of 7 oz. This would give us a 60% microballoon fill percentage. You can take this all the way up to 100% but would not recommend going over 100%. Physical properties will not be dramatically affected when using less than 50-60% microballoon fill in RC-3. In our 7 oz hold example we would then have 5 oz of resin at $.35 each plus 3 oz of microballoons at $.06 each. This gives us $1.75 worth of resin and $.18 worth of microballoons. Add these together and your new resin cost is $1.93 rather than $2.45 previous unfilled resin cost. You would then add in your $.09 mold allocation cost per hold as well as your $.11 dye cost for a total of $2.13 total cost for resin/filler, mold, and dye rather than your previous $2.65 when using straight resin. This is an approximate 25% savings in cost when using the micro balloons.
Once again these are price estimates off of small quantity list prices for starter size material kits. They do not include mold box material cost, glue cost, cost to create or purchase masters to make molds off of, or labor. This is a simple walk through on how to generate a cost estimate for making your own climbing holds. As you were to purchase larger quantities your pricing would decrease dramatically decreasing your cost per hold.
To discuss any of this information or if you would like help using larger volume pricing to accurately calculate your costs, please give us a call and we’d be more than happy to assist you.