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Re: do the forms have to be lined up? STEMS?
By:Greg Steeves
Date: 3/8/2001, 1:44 am
In Response To: Re: do the forms have to be lined up? STEMS? (Pete Rudie)

: I agree, and would add that when the strips go on they will tend to
: straighten, exerting thereby a force upward at the stems. They have quite
: a lot of leverage out there, and can rack the end forms even if they are
: 3/4" plywood and nailed down tight. If you're using an external
: strongback you can build the stem form oversize on the deck side,
: extending all the way to the strongback and fastened to it temporarily.
: This is less likely to be a problem with Nick's internal strongback,
: depending on the length of the taper - longer is better.

Short of using a metal internal strongback I could figure out how to base alignments on the strongback. I didn't trust a wooden strongback to be close enough so I clamped the strongback down and got it close to plumb. Then I

attached the end forms and made them perfectly plumb or as close as I could. I checked that they were on the same line by

attaching two 12" steel rulers on each endform and sighting down them, any error in alignment shows up quite

well. Then I attached the rest of the forms and adjusted the height and level. This is about a two to three hour

job. The biggest problem is devising a system to fine tune the leveling. I clamped a 4' level across the form

being aligned with a 2"x2" on the opposite side. The 2"x2" was modified with two "T" nuts on the side facing the

mounting cleat. Alignment became a simple matter of sliding the form to center it, then with bolts through the

"T" nuts, adjust the level, recheck the centering then screw it to the cleat. When they are all mounted, a final

alignment check is preformed by eyeballing the gridlines that I leave on the paper when I print the forms . This

allows for checking both horizontal and vertical alignment, half the forms can be viewed in this manner from

each end. Its simply amazing how even a small misalignment jumps right out using this approach.

Greg

Messages In This Thread

How precisely lined up do the forms have to be?
Allison -- 3/6/2001, 8:23 pm
Re: do the forms have to be lined up?
Geo. Cushing -- 3/7/2001, 3:20 pm
Re: do the forms have to be lined up? STEMS?
Paul -- 3/7/2001, 7:55 pm
Re: do the forms have to be lined up? STEMS?
Stan Snapp -- 3/7/2001, 11:19 pm
Re: do the forms have to be lined up? STEMS?
Pete Rudie -- 3/8/2001, 12:24 am
Re: do the forms have to be lined up? STEMS?
Greg Steeves -- 3/8/2001, 1:44 am
Re: do the forms have to be lined up? STEMS?
Greg Steeves -- 3/8/2001, 1:38 am
Re: How precisely lined up do the forms have to be
Don Campbell -- 3/6/2001, 10:22 pm
Re: How precisely lined up do the forms have to be
Al Gunther -- 3/7/2001, 10:36 am
Re: How precisely lined up do the forms have to be
Andreas Albat -- 3/7/2001, 12:02 pm