Snaptie Spacing and Rate Placement:
The most common snap tie spacings being used with the Jahn Forming System are shown below. For different rates or pour and/or other tie spacing, contact Masons Supply. Refer to the back cover for addresses and phone numbers.
Plywood Used Strong Way (Face Grain Parallel to Spacing)
Notes: The above recommendations are based on the use of 3/4" Plyform Class I, and 2x4 S4S studs (Douglas Fir-Larch, Southern Pine or equal having a minimum allowable fibre stress of 1,200 psi). Design is based on all formwork members being continuous over four or more supports. Normal weight concrete made with type 1 cement, no admixtures or pozzolan, slump no more than 4 inches and vibration limited to 4 lineal feet or less.
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VIEW PDF (CATALOG PAGE 41)
Footing Plates:
Good forming practices require that a level footing be used as a starting point for all forming applications. Snap a chalk in back of the plywood thickness and nail down a 2x4 plate.
Plywood Panel Erection:
Erect, plumb, nail to plate and temporary brace the first sheet of plywood.
Erect additional sheets of plywood by nailing them to the 2x4 plate and temporary wood cleats at the top corners. Make sure the joints are tight. If panels are to be stacked, ensure that the panel tops are level.
Installation of Snapties and "A" Brackets:
Place the ends of the Snapties through the holes in the plywood. The 43/4" L&W Snaptie, Standard is recommended for use with the Jahn "A" Brackets, 5/8" or 3/4" plywood and 2x4 wales.
Two workmen can install the snap ties with speed and economy. One inserts the tie through the tie hole and the other attached the "A" bracket.
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Proper "A" Bracket Installation:
Installation of Wales:
Install the Walers into the brackets working from top to bottom of the panel and tightening the eccentric as you go. Waler joints should occur at a bracket or a scab should be utilized to reinforce the joint (see sketch).
(Without Waler In Place)
1. Place the "A" bracket on the tie end by slipping the tie end into the slots in the bracket.
2. Rotate the eccentric loosely over the tie end.
3. Drop 2x4 waler in place. Seat 2x4 with hammer, if neccessary.
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(With Waler In Place)
1. Slip the back slot in the bracket body over the tie directly behind the head.
2. Push the bracket toward the plywood until the tie head emerges through the front of the bracket.
3. Rotate the eccentric over the tie head and tighten.
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Inside Wall Panel Erection:
The inside panel sequence is the same as the outside panel described above except for the placement of the plywood panels over the tie ends. This can be accomplished by two workmen by starting at the bottom and moving the panel from side to side and up and down to align the snap ties with the holes in the plywood.
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Inside Corner Forming:
No special treatment is required for inside corners other than the alternating of the wales as shown in the sketch. It is advantageous to start the inside corners with full size plywood panels to facilitate forming the outside corners.
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Outside Corner Forming:
Install the first outside panel in line with the first inside panel. Filler panels, the same thickness as the wall plus the plywood thickness, are then used to fill out the exterior corner.
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Installation of Jahn® Cornerlock:
The cornerlock eliminates costly overlapping and blocking of the wales. Its cam action draws the wales securely together. Place one wale flush at the corner and let the other extend past the flush one. Slip the cornerlock into place with the handle perpendicular to the wale. Nail the cornerlock in place and rotate the handle 90° toward the wale. A snug, tight outside corner is a accomplished.
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Installation of Strongbacks:
Strongbacks are used to aid in form alignment and to tie stacked panels together. Loose 2x4's are used in conjunction with Jahn "C" Brackets and 81/4" L&W snap ties or 43/4" L&W snap ties with the Jahn Tie Extenders to strongback the forms. Normal strongback spacing is 8'-0" on center.
Forming + Accessories 
