Mounting Stringers to Building Form - Jackknife

Outboard designs up to 14'

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Mounting Stringers to Building Form - Jackknife

Postby AndrewS » Mon Oct 24, 2016 6:57 pm

Dear Gentlemen,

What is the best way to mount stringers to the building form?

Many thanks,

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Re: Mounting Stringers to Building Form - Jackknife

Postby JimmY » Tue Oct 25, 2016 9:25 am

Hi Andrew,

I'm not sure I understand your question. If you mean the sheer and chine, then these are typically epoxied and screwed to each frame. If you mean the motor stringers that will be part of the boat, then you need to make them removable (screws and/or clamps) such that you can get to them once the boat hull is framed and sheeted.

I hope this helps.
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Re: Mounting Stringers to Building Form - Jackknife

Postby BarnacleMike » Tue Oct 25, 2016 10:13 am


I'm not very familiar with the Jackknife design, but from this photo


it looks like the stringers help to form the supports for the floor. Take a close look at your plans & instructions. From the looks of this photo, it would almost appear that the longitudinal supports of the building form ARE the stringers.

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Re: Mounting Stringers to Building Form - Jackknife

Postby chugalug » Tue Oct 25, 2016 10:18 am

:roll: Or are you talking about the boards screwed to frames at the set up level line and screwed to the build form? I fastened mine down with screws and using framing square from level build form,fastened an angled piece on each side to help hold in place. :D
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Re: Mounting Stringers to Building Form - Jackknife

Postby Roberta » Tue Oct 25, 2016 10:53 am

Not real familiar with the Jackknife. It appears that it is a smaller outboard cruiser. Typically stringers are used on larger inboards for motor mounting or larger outboards. Stringers are used as a setup level for framing where the floor timbers are in some way positioned on them to set the level of the framing to ensure that the keel, chines and shears are in alignment. Stringer clips are used to fasten the framing to the stringers once the proper location and height are established. C clamps and/or Erwin clamps can be used to secure the stringers to the uprights on the build form. The temporary clamps are used until the stringers are set level both longitudinally and athwart ship. Then a drywall screw or two can be place to ensure the setup remains in place. Clamps and screws need to be placed so that they can be removed later so the hull can be removed from the form and the hull righted.

Here are some pics of my Torpedo build form with the stringers set and framing being set in place. Use diagonals and other bracing to ensure that the form is secure and stable. A large level is helpful in getting the form perfectly level from side to side, front to back, and diagonally. Use clamps when constructing the form and, when level, secure with screws.

build frame 002.JPG
setup 3 003.JPG
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Re: Mounting Stringers to Building Form - Jackknife

Postby AndrewS » Tue Oct 25, 2016 10:37 pm

Dear Jimmy, Chugalug, Barnacle Mike and Queen Roberta,

Thank you very much for your replies. I understand now:)

My teak arrives on Saturday!


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