Hi Richard, don't know if it's any help, but on my Parker 27, the keel is left in the initial "blank" thickness where the sliders are located, ie in my case nominally 60mm thick across the whole keel front to back, this means the sliders are just four oblongs of material the same dimensions front and back, after all, it makes sense not to make that area foil shaped as it is always encased in the keel box. Don't know where you are based but in Waterlooville near Portsmouth, there is a plastics supplier called Ensinger who you can walk into and ask to buy offcuts of various sizes and thicknesses of most types of plastic including Delrin, Acetal and PTFE for peanuts, often only a donation to the coffee fund. I doubt your keel would be any different so once you know the original thickness, you should be able to buy some offcuts of that thickness and trim to shape. I would be very surprised if they were wedge-shaped or different thicknesses, it would unnecessarily increase the production time and costs. regards Martin Watson P27-Frith
Ensinger,
Plastics Manufacturing
Waterberry Drive, Waterlooville, PO7 7XX · (023) 9224 5555