rigging question

OK so pulled the trigger and got a downrigger, weight, etc. Built a mount like one nangusdog did for my OK trident 13 now my question is I still need a platform of some kind to mount the mount for the rigger on and I'm probably gonna use plywood how thick should I use?  Was thinking of using 3/4inch and of course using large area washers, nylocks, and bolts for hardware... Thoughts?

I saw one where a guy used a piece of plastic cut from what he stated was a  cheap plastic cutting board.   I think he claimed it was made from Delrin though not certain he was correct as that material tends to be expensive.    Even the plastic PE cutting boards are surprisingly stiff and tough.  Never have to worry about getting water logged or warping also.

I suggest that you use high density polyethylene ("HDPE") or Ultra High Molecular Weight Polyethylene ("UHMW") for the base for your downrigger. Both kinds of plastic drill and machine easily. HDPE isn't quite as strong as UHMW, but will work just fine.  You can easily find HDPE at plastic fabricators, which use it for making cutting boards for restaurants and other food processors.  One brand name for HDPE is Starboard.  Figure out a design for your base, and then buy some appropriately sized scraps from a fabricator.

if you have a Harbor Freight in your area they have the small cheap cutting boards, Walmart if not.

An advantage of buying HDPE from a plastic fabricator is that you can buy pieces of plastic any size you want in a variety of thicknesses, and it'll be flat on both sides.  A disadvantage of buying discount store cutting boards is that they often have depressions like gutters around their edges, so you may need to cut the edges off to get a flat piece of plastic.  But if you need a fairly small and thin piece of plastic, you may be able to find a suitably sized cutting board at Walmart or some other discount store.

I'll definitely look into the hdpe or uhmw or a cheap putting board since that will last longer with fewer headaches than my wood idea... But I am a little redneckish so I'll figure out something that works for sure...

Do you guys have Tap Plastics up there? They have big bins of scraps that they give away for free or cheap. Should be able to find whatever you need.

Here's my DR mount using 3/8" Starboard for the base:

UHMW is great stuff ... you can fabricate anything out of it. We use it all the time in the seafood plant.