If you ever plan to use a cockpit cover or spray skirt you will want 16-18 mm of space under the coaming. It's not much more trouble to build up the coaming with 4mm pieces than to use thicker pieces. -Wes

Hi David,

I used a 4 foot x 4 foot piece of 1/4 inch ply to get one cockpit apron and six cockpit coaming spacers.  The layout to cut the parts are shown on the blueprints.  That will give you a stack of three spacers for a total of 18 mm.

Lou

I am planning on a cover and spray skirt.  I used the width of my finger as the measure on my first boat for lip height... 18mm... hmmmm

Lou, after posting, I checked the plans for my C18 (the next project ;) and it also said 2x9mm, but also suggested the 3x6mm.  since I am not really keen on a 4mm lip, I am going to take your suggestion and buy a sheet of 6mm, make the spacers and lip out of that. 

Thanks all, sure is nice to have such a great support network :-D

I am looking at the coaming delema myself in the near future. I ordered my 4mm ply from CLC and the plans and full size templates as well. When I looked at the materials needed it said 3 sheets of 4mm Okume --which I ordered but when I recieved my plans and manual book it showed 2 sheets of 4mm and 1/2 sheet of some thing heavier.May be I looked in the WD 12 materials list instead of the WD 12 Hybrid matrials list-I don't know. The coaming spacer height is one of my concerns and the coaming lip thickness is the other. I have the lip cut from 4mm [no asssembly yet] is this to thin? Is 2 thicknesses of 4mm to thick ? Coaming spacer height of 16mm would take 4 layers of 4mm or 8 peices--any other ways of doing this?---Thanks--CZ

I agree that you need some space for a cover or spray skirt. On my WD12 I think the lip is 4 mm and then I added fiberglass to strengthen it and in case of rubbing with the paddle. However, it is more my knuckles that rub, not the paddle.

Ralph