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MarkMK - 1/15/2019 1:48:48 PM

Hi Rob

As a basic rule of thumb, you want to choose the locations with the shortest distance between your inlet and outlet hoses. On something like a bathtub shape, that looks like it would be halfway down each of the long straight sides. Even then, there's likely to be a fair distance between the two, so running your infusion spiral so it runs along the inlet straight edge and halfway around the curve at each end will help spread the resin fairly evenly.

It might also help to lay down some additional strips of infusion mesh at the most distant points from the inlet to help things flow better. By doing so, you'll create channels where there's a double layer of mesh and this will help the flow keep up with the shorter section at the middle. It'll mean using a little more resin but it should, hopefully, help to ensure all areas are thoroughly wetted-out by the time the resin reaches the exit port. I'd probably apply the same principals to both moulds. It looks like you'll need some fairly big pleats on the main tub mould also, to overcome the sheer height of the it so don't skimp on the bagging film, as it will increase the chances of leaks occurring if the bag is overly stretched when pulled down. Assuming that your bag has plenty of slack in it, pull things down fairly slowly, to help avoid the fabric becoming crimped are the highest extremes where the mould curves down. If necessary, put relief cuts in the mesh to help it lay down fairly flat, as crimps and creases here can transfer to your fabric and leave visible signs on the surface of the laminated part. Cut the mesh from the exit side, though, as you don't want to create zones around the inlet where the mesh is no longer joined together, as this will choke the flow of resin and slow things down in places. 

Another option is to place the inlet in the very centre of the tub and run the spiral to both ends, but there's always a chance of 'print-through' from the connector and spiral to the surface of the part unless you've got access to resin runners that are made for this type of approach. You'd also need to install two vacuum ports, one at each side that are both connected to your pump. This might feel a bit complicated if it's your initial project, though.  

I'm not overly certain regarding your connectors. The white one looks like it'll work okay on the inlet side, but the black might only work well for the vacuum line.. Perhaps putting a few layers of breather fabric underneath it before placing it on your strip of infusion mesh (for your resin break) will help make sure it pulls air okay without restriction.