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Re: Skin-on-Frame: Bjorn's Strongback alignment *PIC*
By:Björn Thomasson
Date: 7/2/2010, 1:04 pm

: Need to build a new strongback and I am seriously interested in the
: simple methods used by Bjorn Thomasson. I read that he pulls a
: string down the center and uses that to align the frames. That
: makes sense, but what I don't follow is how he aligns the frames
: at 90 degrees to the string. I can think of a couple ways you
: could do this but I have learned to ask. Someone probably has a
: super simple method to do this.

Kudzu: the method referred to is very simple, perhaps not the most accurate, but relevant in this context. I draw the waterline and centerline on both sides of the molds, align the largest mold very carefully over the string and with a water level to get the centerline vertically correct. From there I forward, and align one mold at the time – since every new mold going forward is slightly smaller, I can see the waterline end centerline aligning exactly with the one on the last mold, when watching from the stem. When all lines appear as one continous line all molds are in perfect alignment. Repeating the process going aft I have aligned the molds in short time. The method does not depend on a perfectly flat strongback.

On my later hulls I have simplified one step further: I drill a small hole (2-3 mm) in all molds in the intersection os the waterline and centerline and put a lamp on one end of the strongback. Then I adjust the molds so I can see the lamp through all the molds (using the light spot on the mold to quickly find the correct placement – dimming the light in the shop temporarily), and line up the waterlines and centerlines as described above.

I believe most of my plans customers now use a cross projecting laser tool to align the molds.

Messages In This Thread

Skin-on-Frame: Bjorn's Strongback alignment
Kudzu -- 7/2/2010, 8:35 am
Re: Skin-on-Frame: Bjorn's Strongback alignment *PIC*
Björn Thomasson -- 7/2/2010, 1:04 pm
Re: Skin-on-Frame: Bjorn's Strongback alignment
Kudzu -- 7/2/2010, 2:47 pm
Re: Skin-on-Frame: Bjorn's Strongback alignment
Björn Thomasson -- 7/2/2010, 3:28 pm
Re: Skin-on-Frame: Bjorn's Strongback alignment
Kudzu -- 7/2/2010, 6:56 pm
Re: Skin-on-Frame: Bjorn's Strongback alignment
yellowbelly -- 7/3/2010, 7:35 am
Re: Skin-on-Frame: Bjorn's Strongback alignment
Kudzu -- 7/3/2010, 10:38 pm
Re: Skin-on-Frame: Bjorn's Strongback alignment
Bill Hamm -- 7/6/2010, 7:36 am
Re: Skin-on-Frame: Bjorn's Strongback alignment
Bill Hamm -- 7/6/2010, 7:38 am
Re: Skin-on-Frame: Bjorn's Strongback alignment
Kudzu -- 7/7/2010, 8:56 am
Re: Skin-on-Frame: Bjorn's Strongback alignment
Dan Caouette (CSFW) -- 7/7/2010, 9:55 am
Re: Skin-on-Frame: Bjorn's Strongback alignment
Bill Hamm -- 7/7/2010, 11:26 am
Re: Skin-on-Frame: Bjorn's Strongback alignment *PIC*
yellowbelly -- 7/2/2010, 11:54 am
Re: Skin-on-Frame: Bjorn's Strongback alignment
Bill Hamm -- 7/2/2010, 8:40 am
Re: Skin-on-Frame: Bjorn's Strongback alignment
Rob Macks / Laughing Loon CC&K -- 7/2/2010, 10:16 am
Re: Skin-on-Frame: Bjorn's Strongback alignment
Etienne Muller -- 7/3/2010, 4:55 pm