Help Please! Loose Foam Pit

[bluefeet]

As president of our booster club, I'm getting ready to purchase new foam for our loose foam pit. This will be the first complete re-fill in years.

We actually have an "L" shaped pit, but for the sake of discussion we'll stick to 1/2 of the L.

The dimensions of this section are 8' wide, 16' long, and 5' deep. The bottom two feet of the pit is covered by tramp (leaving 3" between the tramp and the surface edge).

I've found on the net that the required number of foam squares is calculated as follows:

6" cubes - W x L x D x .70 x 8.00 = # of cubes
8" cubes - W x L x D x .70 x 3.37 = # of cubes

First Question: Do you know if the formula already takes into account perhaps an 'industry standard', the tramp space at the bottom of the pit? Would my depth in this equation be the physical 5' depth, or just the 3' that I need to fill on top of the tramp?

Second Question: I understand that it is ideal to have a slightly rounded filling on top. Regardless of the actual depth to use in this equation, would this resulting # of cubes provide for this rounding...or would you get extra?

------------------------------------------------------------

Types & Sizes of Foam: The foam I'm looking at comes in 6" cubes or 8" cubes. I've gotten a couple conflicting recommendations as to what is best to use.

I've heard that larger is better, creating more 'empty space' between cubes to better absorb the landings.

I've also heard that for smaller children, the smaller cubes are better to keep them from getting to the bottom too quickly (slipping through basically).

Our pit (like most I gather) is used by 1 year olds, and full grown competitive gymnasts. I guess it's not uncommon to have a mix of sizes to best accommodate the variety of shapes, sizes, and weights of the gymnasts.

Third Question: If a mix for us is a given, would you have any experience in guesstimating what this mix might be? 1/2 and 1/2? 60/40?

I've found the following descriptions of the product foam:

ex: CC44140...

...where the CC designates the Combustion Modified (flame retardant), the "44" being the Load Deflection Rate, and the "140" being the pounds per sq" (i.e. 1.40).

From the suppliers I've limited it down to, I have available:

CC33145 @ $0.91 (per 6")
CC44140 @ $1.00 (per 6")
CC44170 @ $1.19 (per 6")

We're of course talking about thousands of pieces of foam, so I'm wondering if you have an opinion regarding the LDI. If we were comparing the middle-of-the-road price to the "33" LDI cheaper product, would the differences be significant? I'm hearing answers to this question ranging between "better, safer, more comfortable" to a more simple suggestion regarding the durability of the product.

If it's strictly durability, we DO have a healthy future budget for annual top-offs. These immediate savings for the mass re-fill would be much better for us. Of course if it's more performance related, I would then lean toward the more expensive.

"pantpant" ...ok, I guess that covers it.

I really appreciate anyone with experience in loose foam building/restocking, sharing their experiences.

-Dave

Ps. I'm also open to supplier suggestions as well, if you have a recommendation.

[bogwoppit]

Can't help at all. We have no pit!!! But I'd love to have your problem.

Good luck in finding the perfect fit for your pit. Ah, so poetic.

[JBS]

Great questions. Here are some answers from my experience.

1. Just order for a 3' depth (the part above the tramp).

2. You would have to order extra. You must also take into account the curve of the trampoline bed. The more foam you put on the bed, the lower it will sag.

3. I would go with the large for safety. Young children can be amused with anything....don't worry about them. I worked and ran an all rec. gym for 8 years...I never even thought about the small blocks.

My preference is firm blocks that hold their shape. It is durability and performance. Soft foam will mush down and become very hard to fluff back up.

[Geoffrey Taucer]

I prefer small blocks. My gym used to have large blocks, then had to replace all the foam, and we went with small ones. I find that with the small ones, I don't get to the bottom of the pit as easily; there were times with the large blocks where I'd tumble into the pit and feel my feet hit the concrete under the trampoline with the large blocks. This has yet to happen with the small ones.

I've also found that the small ones are easier to move around in, so its easier to climb out of the pit, especially for small kids.

[JBS]

The third question is really just a matter of preference. The pit will be looser with larger blocks and a bit tighter with smaller blocks. Ask your coaches what they are looking for. Just stay away from cheap foam that crumbles right away.

[bogwoppit]

Bluefeet, check under gymnastics on ebay. There is a seller with huge quantities of new blocks for sale. The prices are good, I think. Might be worth checking out.

Item number: 110133641758

[Rick McCharles]

Quote:
Originally Posted by bluefeet As president of our booster club, I'm getting ready to purchase new foam for our loose foam pit. This will be the first complete re-fill in years. We actually have an "L" shaped pit, but for the sake of discussion we'll stick to 1/2 of the L. The dimensions of this section are 8' wide, 16' long, and 5' deep. The bottom two feet of the pit is covered by tramp (leaving 3" between the tramp and the surface edge). I've found on the net that the required number of foam squares is calculated as follows: 6" cubes - W x L x D x .70 x 8.00 = # of cubes 8" cubes - W x L x D x .70 x 3.37 = # of cubes First Question: Do you know if the formula already takes into account perhaps an 'industry standard', the tramp space at the bottom of the pit? Would my depth in this equation be the physical 5' depth, or just the 3' that I need to fill on top of the tramp? Second Question: I understand that it is ideal to have a slightly rounded filling on top. Regardless of the actual depth to use in this equation, would this resulting # of cubes provide for this rounding...or would you get extra? ------------------------------------------------------------ Types & Sizes of Foam: The foam I'm looking at comes in 6" cubes or 8" cubes. I've gotten a couple conflicting recommendations as to what is best to use. I've heard that larger is better, creating more 'empty space' between cubes to better absorb the landings. I've also heard that for smaller children, the smaller cubes are better to keep them from getting to the bottom too quickly (slipping through basically). Our pit (like most I gather) is used by 1 year olds, and full grown competitive gymnasts. I guess it's not uncommon to have a mix of sizes to best accommodate the variety of shapes, sizes, and weights of the gymnasts. Third Question: If a mix for us is a given, would you have any experience in guesstimating what this mix might be? 1/2 and 1/2? 60/40? I've found the following descriptions of the product foam: ex: CC44140... ...where the CC designates the Combustion Modified (flame retardant), the "44" being the Load Deflection Rate, and the "140" being the pounds per sq" (i.e. 1.40). From the suppliers I've limited it down to, I have available: CC33145 @ $0.91 (per 6") CC44140 @ $1.00 (per 6") CC44170 @ $1.19 (per 6") We're of course talking about thousands of pieces of foam, so I'm wondering if you have an opinion regarding the LDI. If we were comparing the middle-of-the-road price to the "33" LDI cheaper product, would the differences be significant? I'm hearing answers to this question ranging between "better, safer, more comfortable" to a more simple suggestion regarding the durability of the product. If it's strictly durability, we DO have a healthy future budget for annual top-offs. These immediate savings for the mass re-fill would be much better for us. Of course if it's more performance related, I would then lean toward the more expensive. "pantpant" ...ok, I guess that covers it. I really appreciate anyone with experience in loose foam building/restocking, sharing their experiences. -Dave Ps. I'm also open to supplier suggestions as well, if you have a recommendation.

I posted your question on the Gymnastics Coaching blog:

http://gymnasticscoaching.com/?p=1855

My own opinion is to ask about how long each kind of foam will last. Recently, blocks seem to hold up better than those in the past.

The rule-of-thumb in quantity is to buy the same volume of foam as space in the pit. (i.e. if space above the trampoline is 600 cubic feet, buy 600 cubic feet of foam blocks. This will roughly bring the pit to level, when new. Needless to say, MORE IS BETTER.)

[bluefeet]

Thanks Rick, and thanks to all of you for replying.

I have since gotten a lot of help from Mike Rainey at GMR. I've come to learn that our gym has done business with Mike in the past & he's a well respected pit builder himself.

Regarding the formula I posted, Mike noted that the 70% factor against the area is potentially outdated. It depends largely on how the pit was created. Older pits typically have tighter tramps, mounted lower (closer to the floor). He prefers to see much looser tramps, mounted closer to the surface (2' from the surface vs. 2' from the floor).

He went on to describe that with a loose tramp, he's found that the factor in actuality could be as much as 115% of the area.

With our budget, I'm shooting for closer to 100%...I'm thinking this should be enough (with enough salvageable foam to fill if needed).

Regarding the LDI and Weight, I'm confident now that the 35 LDI is quite standard (gyms using this foam including Woodward, and other popular gyms/camps).

I'll be placing my order this week. The kids are pretty excited about getting some pretty new blue foam