July 2, 2020

Steam Launch Blog #27

July 2018 - Sept 2018 with summer break in between - Onto the Sheer

July 2018 - Sept 2018 with summer break in between

On to the sheer! We used battens to visualize this strake; the lower one being placed on our sheer marks from lofting process. The overall plan (#2-11) indicates the gradual, constant tapering width of the sheer at the ends. You'll note that middle ten or so frames are pretty much the same - the middle propulsion compartment.

Interestingly, the sheer batten naturally twisted into place as it twisted at the ends to follow hull contour; hence a natural rise at both ends without much effort to force a straight batten into shape. Much like we found on Reliance.

Since our crew had fallen in love with tongue depressors, we did that again. And as seen in the third photo, the batten curves when laid flat. This template was very useful navigating around knots and staying in heart wood of our bargain basement lumber.

Fortunately our neighbor Dan Shea had a profiling machine with which to get the standard HMCo bulb profiled. In fourth photo Dan is introducing his high-school boat builders to the process of making a sheer strake. I'll note that Dan asked if we could remove as much excess wood from our blank. We did this with table saw cutting kerfs almost down to the profile marks.

After this it was back to our shop to lay out stations and make the tapers at each end  - the standard process of marking the taper on stations and bending a batten to shape. Unfortunately, neither Bill nor I could convince our team to use a HMCo long wooden plane. I guess our motto "Make mistakes faster with power tools!"  ;>)  We then notched the rabbet out - 1/4" deep for the mahogany plank, and half its width so that mahogany planks would overlap cedar strakes by half.