Frequently Asked Questions
Q: How much tension do I need? A:
Johnson Architectural Hardware recommends 350 lbs. of tension on each cable assembly for a cable railing. 350 lbs. of tension is based on following the guidelines in our Basic Framework section for railing framework (please see page 9). If one follows Johnson's guidelines, Johnson knows through in-field experience and through the Modulus of Elasticity formula that code will be satisfied.
Q: Can I take 90 corners? A:
No. A true 90 corner will tweak the cable no matter what construction of cable is used. The physics of the cable does not allow the tension to be equally transmitted from one side of a corner to the other side. Tension has to be maintained throughout the entire length of the cable run to meet code. Tension in a cable is not like electricity in a wire. An end fitting should be used to make the corner transition and keep the cable tension in a straight line.
Q: What end attachments do I use? A:
End attachments are the designer's personal choice. There are many ways to accomplish the same thing with different fittings. End posts and aesthetics are the most important factors in determining end attachments. See page 26 for end fittings.
Q: Why is Johnson so strict with cable spacing, tension and framework? A:
Johnson is strict with our specifications because we want you to meet code. Cable railing is not a new business to Johnson. Johnson has been manufacturing cable fittings since 1958. Other so-called "cable experts" may tell you that you can get away with this and that, but Johnson has the experience and wants you to meet code the first time. If you follow what we prescribe in this catalog, you can be confident you will meet code.
Q: What are the after swage dimensions? A:
The table below shows the After Swage Dimensions for machine swage fittings.
TERMINAL WIRE SIZE 1/8" 5/32" 3/16" 7/32" 1/4"* 1/4" 5/16" 3/8" * with 7/32" die THREAD DIAMETER 10-32, 1/4" 1/4", 5/16" 1/4", 5/16", 3/8" 5/16" 5/16" 3/8" 1/2", 5/8" 5/8" BEFORE SWAGE DIMENSION .250 .297 .359 .427 .427 .494 .635 .703 AFTER SWAGE DIMENSION .219 .250 .313 .375 .375 .438 .563 .625
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Johnson Architectural * Tel 800.874.7455 * Fax 860.873.8589 * www.csjohnson.com
Q: Can I make my framework out of aluminum? A:
Generally, aluminum is too soft for cable railings. Aluminum and stainless can react and cause electrolysis. If properly insulated and structurally equivalent to the framework described on page 9, an aluminum framework can be used.
Q: What grade of stainless steel does Johnson use? A:
For all major components Johnson uses Type 316 stainless steel. Type 316 is low-carbon "18-8" chromium-nickel stainless steel modified by the addition of molybdenum, which greatly increases its corrosion resistance.
Q: Does Johnson offer fittings in steel or galvanized? A:
No
Q: What are the after crimp dimensions for the Johnson 53-215 tool? A:
1/8" cable = .185; 3/16" cable = .260 Cross-Section of Hand Crimp Terminal
Caliper
Q: How can I tell right hand thread from left hand thread? A:
Threads slope up to right when the stud is held vertically for right hand thread or slope up to the left for left hand thread.
Right hand thread
Left hand thread
Q: What is the minimum hole size to pass a stud through an intermediate post? A:
1/8" and 3/16" cable - 3/8" hole 1/4" cable - 1/2" hole
Johnson Architectural * Tel 800.874.7455 * Fax 860.873.8589 * www.csjohnson.com
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