Foam Filling Hole Spacing?

[76SeaRay]

Is there any kind of "rule of thumb" or maximum distance between holes for flotation foam filling stringer cavities? I have two cavities that are 12 inch wide by 42 inches long (front to back) and roughly 6 inches deep on one side and 8 inches deep on the other side (sloped bottom of the hull). I also have two cavities 12 inches wide by 96 inches long with roughly 6 inches deep on one side sloping up to the bottom of the decking on the other side.

So, would two 2 inch holes 30 inches apart (6 inches forward of the transom and 6 inches aft of the front engine bay bulkhead for the 12 x 42 seem reasonable? Would the 42 inch length fill properly and completely using this hole spacing and poured from the front with the bow raised? Would 4 holes seem about right for the smaller cavity that is 96 inches long or would 3 holes work?

 

[chevymaher]

that is what i did tilted the boat as much as I could. It fills like soap suds in a bucket would. Here was mine there are 2 rows of holes because 2 sides of a stringer. And the video is how it acts expanding. I had a little much in the side and it was pushing out.

 

[todhunter]

I had almost 96" between my two holes on my longest run. It filled fine.

 

[flashback]

Probably get some heat but I wouldn't put any foam in it.

 

[76SeaRay]

Looks like I will use two holes on the 12 x 42 and three holes on the 12 x 96. Thanks for the info.