View Full Version : Fixing A Hollow Board

25th October 2009, 04:39 PM
While sailing my board, I noticed that there was a 'soft' spot on the deck just in front of the forward right footstrap. My board is from 2005 and has been lying outside for possibly several years. When I opened the pressure valve a lot of pressure was released from the board, however, the soft spot still has not gone away.

Is it possible that lying in the sun the gas inside the board expanded enough to unglue the outter layer from the polystyrene inside?

I also noticed that the board has a ding repair, but I don't think the soft spot has anything to do with it.

I've heard about spray foams which expand quite powerfully. If I can get my hands on some I'm contemplating drilling a small hole in the center of the soft spot, inserting some explanding foam, and then sealing it with a regular repair kit.

Any advice for this sort of problem/using expanding foam?


25th October 2009, 09:55 PM
Hi Agrelon,
"Soft deck syndrome" most often results from heel dents/dings that indicate a board has been sailed very hard, or jumped and landed flat and the impact of the sailors heel has compressed the foam layer under the deck.
It can be fixed, but I do not think putting one hole in the dent and injecting foam will work as the foam needs to spread and expand. putting the foam in a central hole, with
several smaller holes around the periphery of the dent might work.
The best way to fix it is to open up the entire dent, remove the crushed foam, then add
the layers of foam and glass back in the same "build up" used to manufacture the board.
Check out


Eva takes you through all the steps to correctly repair "soft deck".
Hope this helps,

26th October 2009, 01:47 AM
It is possible to repair as you suggest but only if you know board to be dry and be VERY carefull with the foam; inject it through one hole but have another to let excess out. Do it in a warm room . (foam is lighter /expands more in warm) and be very carefull to not inject too much;it carries on expanding after leaving container. (unless you use 2 part; in which case be even more carefull !!! It will "blow" your board up beyond repair if you either inject too much or excess isn`t allowed out. (I know from experience !!!)

Other issue is to make sure foam you use does not corrode foam in board !!! Some foams will "eat" the board foam .(Especially if board foam is polystyrene based) (You end up filloing one hole and making another !! Dont ask why I know !!!) (Do a check first with a bit of foam from the holes)

I`ve got an old F2 (power glide) which was really soft under footstraps.Repaired as mentioned and its still going 3 years later. (Cover holes with epoxy putty; I didnt bother with glass etc; holes were small)

Good luck !!!

26th October 2009, 11:57 AM
Ok great, thanks for the advice and good to know I'm not alone on this one. I'll see if I can get my hands on some foam.

9th July 2010, 07:32 PM
How did it go agrelon? I also have a softdeck between the mast and front straps (on both sides) and I believe it comes from hitting the deck with my heel after I suddenly come to a lull and try to take out my foot out of the strap asap. It could also happen when my waterstart is not so good, so the wind pulls me quickly from the water. The deck is not yet peirced, in few days I am planning to replace the damaged PVC layer, insert some urethane foam to the EPS foam and put some new glass clothing. Not in the mentioned order, of course. :)
Based on this experience, I have changed my style of riding, paying a lot more attention to move in smooth and soft steps around the board. :)

10th July 2010, 03:40 PM
Hi Spinoutforever,

I never got round to doing the repair, as I later sold that board. The soft spot didnt ever crack or break so I guess in the short run it's not a big deal.

Hope you can solve it none the less,