Single vs. Double Plank Studs

[DNewbie]

Uno mas preguntas, por favor. Proceeding from my position of almost complete DN ignorance, I’m weighing options for plank attachment. I see that plank studs and plates can be either single or double. My hull was built to the Goodwin template and calls for four 1” holes in the attachment area. I've not yet drilled them. I’m confused about the spacing. Starting from the bow, the spacing between the holes are 2”, 1 ¾” and 1 ¾”. I think this is a standard layout but I’m not sure why there is a difference in the spacing. Obviously, a single stud arrangement will work in any hole but I’m having a harder time visualizing a double stud arrangement. Can anyone shed some light on the differences between the two arrangements and explain the merits of each?

[Geoff Sobering]

... the spacing between the holes are 2”, 1 ¾” and 1 ¾”. I think this is a standard layout but I’m not sure why there is a difference in the spacing. Obviously, a single stud arrangement will work in any hole but I’m having a harder time visualizing a double stud arrangement.

That pattern is driven by the hole-spacing in the standard Sarns attachment plate (for use with a single-stud plate).  I don't know why the forward hole is further forward, but I assume it's there for super-light wind.

You should drill the holes in the floor of your boat to match whatever hardware you decide to use (I've always used the plate as a template for locating the holes).

For far as I know, the advantage of the double stud system is that the plank loads are distributed over four studs instead of two, so it should be stronger/more reliable.
FWIW, I've always used single-stud plates and never had one fail in-use.

Cheers,

Geoff S.

[Bob Rast DN1313]

I have been using the double studs since I started .Lou Loennecke  used to get them from Sarns  special order. they are not difficult to make .The hull attachenebt plate I use has 10 holes 2" on center to accommodate the double stud plates. The reason i like them is double the protection of a stud breaking from bumpy ice and fatigue. the main advantage i see is leveling the runner plank to the ice.
There are a number of schools on runner alignment but the idea is to have the chocks level to the ice when  the boat is under load.  as you start to load the boat as if sailing block to block, the plank goes down in reletaion to the front runner and will tilt up changing your runner alignment. with 1 stud you have to shim the stud plate to desired angle to keep side runners parallel to  the ice.
With double studs you can add a rubber washer or 2 t fron or rear stud to get desired adjustment.We load up the boat as if sailing sheet in and put a small level under outside edge of chock.
Either way works
Bob Rast 1313