Good Day Brian
I've just finished the funnel for my Bathurst Class, the funnel dimensions are 91mm in height, 32.5mm long and 29.5mm wide. I found the easiest method was to plank, then sand the ridges flat.
I started the funnel by photocoping the plans, cutting out the picture and sticking it onto some scrap 1.5mm ply, and sanding to shape (remembering to take into account the plank thickness). I then marked the centre line and drilled two holes (1/8") into my funnel template (to take the bolts that will hold the plastic pieces in place).
Five pieces of 1.5mm plastic were then cut to the vague shape of the template. Next, I marked the holes from the template onto the plastic, and drilled the holes through all five pieces. These were then numbered and the front marked and then bolted onto the template. The plastic was then filed/sanded down to the same shape as the template. With the pieces sanded to shape, the bolts were removed.
Using the template, I then drilled two more holes into some scrap MDF. Two pieces of 1/8" tube were then placed into the holes in the MDF. The No.1 plastic piece was then slid over the plastic rods, down to the MDF (the base of the funnel), the rods were then checked for squareness, and these pieces were then glued into place. When this had dried, the other four pieces were slid on to the rods. The top was marked and glued into place. The others were then placed equally between the top and bottom and glue onto the rods.
After this frame work had dried, I glued .70mm x 1mm plastic strips around the outside, this was then left to dry. Once dry the planks were trimmed to size. At present, I'm sanding down the ridges on the strips to get a smooth, flat finish.
Richard
