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PLANK TAPERING JIG

Greg Meyer
greg7118@uneedspeed.net
Last Update: 3/17/2005

TAPERING DECK PLANKS

In the process of laying deck planking, essentially all the planks on the Constitution deck, all the planks had to be tapered. Since there are a lot of planks necessary to cover the Constitution deck, I thought it imperative to make a jig to help me taper these deck planks, which numbered close to 50 planks to completely cover the deck.

Here is my jig for tapering planks - not sophisticated, still needs a lot of work but works. I'll explain below how I use it in a minute - but first - it is essentially a square board (about 12"x12"), two metal (brass in my case) straight pieces (12" long, 3/4" wide and 1/16" thick), a couple of Quick-Grip clamps, a straight-edge ruler and a #11 X-acto blade to cut the plank taper by dragging it along the straight-edge ruler.

I place the plank to be tapered between the two brass strips (guides); close the brass strips tight against the plank and clamp with a pair of Quick-Grip clamps. This secures the strip to be tapered. Then I align a straight-edge ruler along a line on the plank that I drew (actually I used indented points I made with my proportional dividers) that represents the required taper and slowly cut the plank along the straight-edge ruler edge with a #11 X-acto blade. The plank to be tapered will have very narrow and thin pieces of wood removed (just lots of short straight cuts) - so - it is imperative to clamp the plank tight, such that it doesn't move/slip in the process. I like to work with planks of significant length (about 24" or so, which will require sliding the plank between the brass guides and retightening); the overall planks should be just long enough so it can span the entire length of the deck. I then cut the tapered plank into required lengths (or mark cut lines on the long plank to represent shorter plank lengths) before gluing to the deck.

Now the process of tapering the deck planks (Constitution):

- I first cut the plank to the correct length; in my case, such that it fits between the last plank layed and the stern of the ship (or wherever it ends); some deck lengths are greater than the deck planking material;

- then using a Sharpie marking pen, I blacken one edge to similate cauking. The blackened line will be on the outside edge - toward the bulwarks - when glued to the deck flooring. You do not have to blacken both sides;

- using proportional dividers, I find out at what bulkhead the area to be planked starts to get smaller (this is the start of the taper)

- place the plank on the deck and annotate with a pencil this bulkhead and the remaining bulkhead positions on the plank to be tapered;

- using a gang of planks (small pieces of the recommended planking placed side by side at the widest area), determine how many planks it will take to plank the whole area (this assumes that the planking material used is given/provided - which it is on the Constitution);

- set the proportional dividers to this number (I like to keep the planking area small - 8 or under - for this reason - if larger, then break into two or more bands); the Constitution planks were very narrow and it took almost 50 planks to cover the entire deck, side to side;

- measure using dividers at each annotated bulkhead and annotate the amount to be tapered along the deck plank, using the small end of the dividers. I like to push the small end point into the wood for the mark and not use a pencil; obviously, the material removed from the plank is on the side opposite to the blackened side;

- place the plank into the tapering jig as described above;

- line the straight edge along the points impressed along the plank. I like to use my Optivisor (magnifying glasses that fit on the head - frees up both hands) to see better. If there is a change in width, several short cuts will have to be made, then moving the straight edge to the next fairly linear row of points;

- cut along the line of points very slowly and lightly, going back over the line several times until the cut is completely through the plank (you don't want the plank to split or the blade to go off on some tangent);

- sand the edge using the True-Sander sanding block by dragging the plank over the sanding block;

- check the plank by putting it in position and eye-ing along the plank to see if it looks right (too wide in places, etc) and continue sanding until satisfied.

- also, check the fairness of the plank along the line it will lay. It is best to try to temporary anchor the plank in place with your hands by holding both ends in place. If a gap appears or it just doesn't lay right or appears to weave in and out - find out where the problem is and go back and sand out the problem. When this plank is glued and if you still has a gap that would require you to push the next strake to fit snuggly against the plank next to it other than at the end points - an unwanted curve or waviness will occur - and I call these places in the curve "inflection points" - where the curve changes direction from clockwise to counter-clockwise or vise versa. Eyeballing along the plank will show these unwanted curves in the plank; sand these unwanted areas;

- when ready to glue, put glue on non-blackened plank edge and on any hull structure (bulkhead floor) that the plank will be fastened to. I use Weldbond wood glue in a glass bowl and a small brush to apply the glue; a little water added to the brush helps thin out the glue and makes it easier to apply to the edge. Let the glue (Weldbond) set for a minute or so to become tacky before setting it up against the adjoining plank. Have a damp paper towel close at hand to clean up any glue spill that gets on the planks. Make sure glue is cleaned away from the outer plank edge so that the next plank will fit snuggle against it. Deck planking is fairly level and without any difficult bends - so little to no holding is required for any extended time.

I got the following input from a fellow modeler:

Looks like a great method and setup for a temporary jig. Have you given some thought yet to how you could make it into a permanent assembly?

- Iím thinking about one stationary brass piece with a second sliding brass piece which could be tightened with thumbscrews into blind nuts for the clamping piece.

- How about making the straight-edge part of the jig by attaching one end of it to the stationary brass piece, and let the other end be free to move? You would accommodate the angle of the cut by the position of the plank between the two brass plates as well as the angle made by the swiveling ruler.

- Iíd incorporate some kind of friction mechanism in the stationary end so that the swinging ruler had some more rigidity to it, and wasnít flopping around loosy-goosy.

- The 1/16Ē brass clamping plates seem awfully thin for a rigid, permanent setup, yet you donít want a piece so thick that it interferes with the cutting process.