Layup is the process of actually building together all the component parts of the snowboard and laminating them together with epoxy resin. This is a time critical part of the build - good preparation is essential, along with a clean and organised working area. Once you mix your epoxy you only have limited time to finish the job !
^ Epoxy resin and hardener
Position the base on a steel sheet very accurately so the centerline of the base corresponds to the centerline of the steel sheet. The steel sheet has been thoroughly waxed with mould release wax (slipwax) on both sides to enable an easy cleanup after pressing. Use thin double-sided tape to hold the base down - two tiny strips at the very tips seems to work well for us.
^ Base lined up on the bottom steel sheet
^ Measure out the resin to hardener ratio accurately
^ Stir the resin mixture until thoroughly mixed
Pour a line of resin down the centre of the base, and use a squeegee to spread it all about until the entire base is well covered in epoxy, put extra over the edges. Using dyed epoxy makes it easier to see spots that have been missed. Also, put epoxy off the board in a 25mm border surrounding the base. This is for the overhanging layers of glass to stick down to, and prevents bubbles forming close to the edge / sidewall. If you use rubber VDS strips now is the time to wet them out by immersing them in epoxy. Position them accurately over the steel edges.
^ Wetting out the base with Epoxy
At this point you can add rubber strips (often referred to as VDS). These are wet out in a pool of epoxy on the base, and laid into position above and overlapping all steelwork.
^ Wetting out the rubber strips
^ Fitting rubber strips above the steel edge
^ Fitting rubber strips above the steel edge
^ Rolling out the first layer of triaxial glassfibre
The lower layer of triaxial glassfibre is rolled into position. On the photo above you notice a stray insert - two inserts are superglued to the base in the correct locations. These will help the core to align perfectly with the base and not shift during pressing. A small cross must be cut in the fibres at that point to allow the insert to pop through.
^ Wetting out the first layer of reinforcement
Pour epoxy onto the glassfibre and use a squeegee or fingertips (in gloves) if you prefer to work it into the fibres. The reinforcement is wet out when it has gone transparent. Ensure that it is thoroughly wet out especially along the sidewalls and around the tip area. You do not want to leave great pools of resin, as much of it will get squeezed out and wasted during the pressing stage.
^ The first layer is almost completely wet out
^ Fitting inserts into the wet out insert holes
We do not usually paint the underside of the core with resin, but rely on the resin contained in the lower reinforcement layer to squeeze out and adequately cover the core. Roll the inserts around in a pool of epoxy to thoroughly coat them. Use your fingertips to wet out the holes in the core and then fit the inserts into the core.
^ The core in place above the lower reinforcement layer
The core is then positioned accurately over the base so that the sidewalls are correctly `exposed` over the edges and no wood overhangs. Using the glued insert trick, alignment is very easy to achieve.
Wet out the top of the core and the tipspacers and position the tipspacers accurately at the ends of the core. They will most likely want to curl up and misbehave - your upper reinforcement layer will hold them down once wet out with epoxy. You will probably need to adjust the alignment once the upper layer is wet out.
^ Fitting the tip spacer
^ Rolling out the upper reinforcement layer
^ The upper reinforcement layer is wet out
^ Adding the topsheet
Lay the topsheet carefully onto the snowboard. Remember your orientation - hopefully you have been keeping track of which end is nose and which end the tail ! Once the topsheet is in position, use a dry cloth to buff it down - the buffing serves two purposes - it cleans off any dust or particles above the topsheet (which make really huge dents even for tiny particles) and it helps you to push any air bubbles out. During the buffing process, be vigilant not to allow the topsheet to slide out of your carefully aligned position.
^ The topsheet - protected with a masking layer - is positioned accurately over the laminated board
^ Apply the upper steel sheet and tape together
Add a second steel sheet above the topsheet. This steel sheet should be thoroughly waxed with mould release, and before placing over the board the inside should be checked for any contaminating particles. Little bits of sawdust etc should be removed as they will dent the top of the board.
The top steel sheet can be taped to the lower sheet using masking tape around the tips. We place our board and steel sheets inside a plastic sleeve to protect the press from dripping epoxy - saves a lot of cleaning up ! Carefully mark the whole piece with a centerline to enable you to accurately position it in the press.
^ Into the press it goes - bake at 95 degrees C for 60 minutes and cool to 60 degrees C for demoulding
The pressing cycle depends on your epoxy. We pre-heat the press under pressure to 95 degrees Celsius during the layup. Once we are ready to load the press, we depressurise it and then carefully insert the packaged board into the mould. This can be a bit tricky - it is pretty essential that you check beforehand that everything is going to fit. You should also mark the mould on the press with a centreline corresponding to the board you are building - you can align it with the centreline you marked on the board package.
The press is then pressurised and allowed to ramp up in heat to the final temperature. The opening and loading process cools the press slightly (and for safety during loading we isolate the press from the mains electricity). So it takes a little time to resume the curing temperature. The cure temperature is maintained for as long as required by your epoxy. For us using R&G Resin L, 60 minutes at 95 degrees Celsius works beautifully - any hotter and our plastic sleeve melts ! Once the curing phase is over, we switch off the heating system and monitor the cooling process while keeping the board under pressure. If you demould too hot, or depressurise during cooling there is a risk of warping the board. We demould once the board has cooled below 60 degrees Celsius.