We are going to start this particular build by gluing up the tail block area, then after that is affixed, we’ll move on and attach the rail material to this wake surf board project. Now we want to pay careful attention to the joint between the tail block and the rail material. Our “plan” is to stagger the layers so that each joint has at least one side covered or backed by a solid section of the high density foam material. That is probably easier said than done, but we’ll give it a go.
Now in order to create a staggered almost stair step looking joint at the tail block, we are going to cut each piece of the material used at the tail block the same length. In that way the first pieces down will actually extended further up the sides of the wake surf board, as the second and third pieces will have to traverse a larger radius. What that does, is each succeeding layer doesn’t extend as far up the sides of the wake surf board. It’ll be clear once we post the pictures.
We’ll start this tail block glue up by assembling all of the pieces and also our core. You’ll note that the deck side of the core is still unshaped at this time. We use a one pound density foam and it is very floppy when shaped down to the dimensions of our wake surf board. Once the rail material is attached we’ll gain some rigidity, but until then, it’s almost impossible to shape accurately. So, we’ll leave the deckside shaping until we have some added rigidity along the rails of the wakesurf board.
We use epoxy for all of the glue up work. The core is EPS and will melt with the exposure to styrene contained in many solvent based adhesives. Now there is some room for experimentation here, there are any number of different adhesives with different properties that can be used and MIGHT deliver different performance. We used the epoxy due to convience and we are striving to build up a stiffer rail line.
We don’t have a good picture of it, but we basically slather epoxy over all of the joining surfaces of the tail block material and also on the eposed part of the EPS where the tail block material will attach. We don’t attempt to bend the tail block material at this point, we’ll use the vacuum bag for that. Instead we just attached the tail block material to the flat area at the very back with tape and then very carefully slide the entire project into the bag.
In the following picture you can see the entire project is in the vacuum bag, but we haven’t pulled a vacuum yet.
We are able to clamp the hose that runs from the vacuum pump to the vacuum bag, which halts the pressure exterted on the project at that particular stage. In this way we can manipulate the materials inside the bag. What we’ll do here is bend the tail block materil in towards the core as teh vacuum is being pulled, thereby forming the tail block into the core. Here is what that process produced.
What we should explain is that after we “massage” the pieces inside, we unclamp the hose to allow the vacuum process to continue. This is repeated until we have everything in place like we want. Once it’s fully clamped we leave the pump and hose open until the epoxy has cured. Also, if you look carefully you can sorta see the staggered end of the tail block.
So that’s the process for attaching the tail block and we’ll pop this wake surf board out of the bag shortly and then attach the rail material. Thanks so much for following along.