Frequently Asked Questions

Marine faqs Architectural FAQs

Marine FAQ’s

What is a Turnbuckle?

A Turnbuckle is a metal coupling device consisting of right and left threaded members screwed into an internally threaded body which when rotated expands or contracts.

What is a Machine Swage Fitting?

A Machine Swage Fitting is attached to the cable by a swage machine which cold forms the fitting directly to the cable. A swage fitting should not be confused with Hand Crimp fittings or other hand tool applied fittings. A specialized swaging machine is the only way to attach swage fittings to cable. Swage fittings cannot be Hand Crimped, welded, glued, hammered, or attached to a cable by any means other than a swage machine.

What is a Hand Crimp Fitting?

Hand Crimp fittings were first designed and manufactured by C. Sherman Johnson Co., Inc. in 1969. Hand Crimp fittings are attached to the cable with a Johnson-made Hand Crimp Tool model #53-210 or #53-215. Hand Crimp fittings should not be confused with Nicopress fittings. Nicopress fittings have sleeves that are made from soft copper alloy and compress very easily. All Johnson Hand Crimp fittings are made from stainless steel and cannot be swaged, welded, glued, pressed in a vise or with vise grips, or attached to the cable by any means other than the Johnson tool #53-210, #53-215.

What is a Mechanical Fitting?

A mechanical fitting is attached to the cable by the fitting compressing the cable with a cone inside the fitting or the cable. Mechanical fittings are assembled to the cable with simple hand tools. Mechanical fittings are larger in diameter than Swage and Hand Crimp fittings and can be reused with a new cone, but carry a hefty price tag.

What type of cable do I use?

Generally, 1×19 cable should be used for all railing applications. 1×19 cable is stiff and low stretch, perfect for railings with runs up to 50 feet. 7×7 cable is more flexible with more stretch, and can be used for railings with very short runs. 7×19 cable is very flexible and should never be used for cable rails.

Do I need a turnbuckle in my cable assembly?

Yes. In order to achieve proper tension in the lifeline and to remove any stretch in the cable, a turnbuckle is required.

Does Johnson make cable assemblies?

No. Johnson manufactures the fittings but does not make complete cable assemblies. Our 45+ year history enables Johnson to provide you with a rigger near you. Please call us for the information you need.

How much tension do I need?

Offshore regulations require that lifelines deflect no more than 50mm (2”) when a force of 11.2lbf is applied midway between stanchions. This is a good guideline for the cruising sailor as well.

What end attachments do I use?

Normally a turnbuckle on one end and a toggle jaw on the other. If you are terminating the lifeline on the deck, use a deck toggle. If a gate is involved – see below.

What are the After Swage dimensions?

The table below shows the After Swage dimensions for machine swage fittings:

Terminal Wire SizeThread DiameterAfter Swage Dimension
1/8"10-32, 1/4".219
5/32"1/4", 5/16".250
3/16"1/4", 5/16", 3/8".313
7/32"3/8".375
1/4"5/16", 3/8".375 or .438
5/16"1/2", 5/8".563
3/8"5/8".625
When do I know when it is time to replace my lifelines?

Lifelines should be inspected yearly.  Vinyl coated lifelines are particularly prone to corrosion where the wire meets the swage fitting.  If the vinyl turns rusty in this area, it may be time to replace the lifelines.

What is the best way to duplicate my present lifelines?

If your present lifelines fit correctly, the easiest and best way to replace the lifelines is to mark the position of the turnbuckles, remove the lifelines from the boat and bring them to a qualified rigger who can make up a new set.  Existing turnbuckles and pelican hooks should be able to be reused.  If this is not possible or if you are putting new lifelines on a boat, download our lifeline measurement form.

If I want to do it myself, what tools are required?

As swaging machines are very expensive, most do-it-yourselfers use our Hand Crimp fittings.  When using these fittings YOU MUST USE our tool 53-215 or 53-210.  The only other acceptable tool is the National Telephone Supply Company “Nicro Press” tool 64CGMP.  Is you use this tool, use the “C” die for 1/8” cable and the “G” die for 3/16” cable.  All other tools are designed to crimp copper fittings – not Stainless Steel.

What is the easiest way to add a second lifeline?

If your stanchions are not drilled for a lower lifeline, the easiest solution is to use our pulpit anchor (part #29-501) and stanchion eye (part #29-502).

What parts do I need if I want to add a gate?

Along with an additional stanchion you will need a couple of stanchion braces (our part # 40-200).  In addition you will need one swivel single gate eye, one swivel interlocking gate eye and a pelican hook.  To tension the short span of wire between the gate and the stern rail, a short adjuster is used.

What grade of stainless steel does Johnson Use?

For all major components, Johnson uses Type 316 stainless steel. Type 316 is low-carbon “18-* chromium-nickel stainless steel modified by the addition of molybdeenum, which greatly increases its corrosion resistance.

Architectural FAQ’s

Cable has become an excellent railing material because of Johnson Architectural Hardware.

When the natural beauty surrounding a home or building is too precious to block with an ordinary railing, Johnson’s cable railings create an unblocked view and satisfies code. Cable will take any path you make for it, but there are some rules to follow in order to satisfy code for railings.

Below is a guideline to commonly asked questions.

What is a Turnbuckle?

A Turnbuckle is a metal coupling device consisting of right and left threaded members screwed into an internally threaded body which when rotated expands or contracts.

What is a Machine Swage Fitting?

A Machine Swage Fitting is attached to the cable by a swage machine which cold forms the fitting directly to the cable. A swage fitting should not be confused with Hand Crimp fittings or other hand tool applied fittings. A specialized swaging machine is the only way to attach swage fittings to cable. Swage fittings cannot be Hand Crimped, welded, glued, hammered, or attached to a cable by any means other than a swage machine.

What is a Hand Crimp Fitting?

Hand Crimp fittings were first designed and manufactured by C. Sherman Johnson Co., Inc. in 1969. Hand Crimp fittings are attached to the cable with a Johnson-made Hand Crimp Tool model #53-210 or #53-215. Hand Crimp fittings should not be confused with Nicopress fittings. Nicopress fittings have sleeves that are made from soft copper alloy and compress very easily. All Johnson Hand Crimp fittings are made from stainless steel and cannot be swaged, welded, glued, pressed in a vise or with vise grips, or attached to the cable by any means other than the Johnson tool #53-210, #53-215.

What is a Mechanical Fitting?

A mechanical fitting is attached to the cable by the fitting compressing the cable with a cone inside the fitting or the cable. Mechanical fittings are assembled to the cable with simple hand tools. Mechanical fittings are larger in diameter than Swage and Hand Crimp fittings and can be reused with a new cone, but carry a hefty price tag.

What end attachments do I use?

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 21 for end fittings.

What type of cable do I use?

Traditionally lifelines have been made of 7X7 white vinyl coated cable.  This smooth cable is easy to grab onto and gives a traditional look.  Boats racing under ISAF or ORC regulations must use uncoated stainless steel cable. 12 Strand Spectra or Dyneema line is becoming more popular for cruising boats and boats not racing under offshore regulations as it is very strong, UV resistant, easily installed (no tools required) and does not rust.

Does Johnson make cable assemblies?

No. Johnson manufactures the fittings but does not make complete cable assemblies. Our 45+ year history enables Johnson to provide you with a cable fabricator near you from across the country. Please call us for the information you need.

What size cable do I use?

3/16″ cable is the most popular size and good for most railing applications. In high traffic applications such as airports, stadiums, or amusement parks, 1/4″ cable is strongly recommended. For residential applications where view and unobtrusiveness are paramount, 1/8″ cable works well.

Do I need a turnbuckle in my cable assembly?

Yes. Cable works great for railing but only if you have the ability to tighten it with a turnbuckle or with a through-bolted threaded terminal. Even if you had some way of pre-tensioning the cable and attaching it without a turnbuckle or threaded terminal, the cable would eventually stretch through people leaning against it, children climbing, the building settling, etc… You want the ability to go back six months later and tighten up the cable.

How much tension do I need?

Johnson Architectural Hardware recommends 350lbs. of tension on each cable assembly for a cable railing. 350lbs. of tension is based on following the guidelines in our Basic Framework section for railing framework (please see page 7). If one follows Johnson’s guidelines, Johnson knows through in-field experience and through the Modulus of Elasticity formula that code will be satisfied.

Can I take 90° corners?

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 throught 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.

What end attachments do I use?

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 21 for end fittings.

Why is Johnson so strict with cable spacing, tension, and framework?

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.

What are the After Swage dimensions?

The table below shows the After Swage dimensions for machine swage fittings:

Terminal Wire SizeThread DiameterAfter Swage Dimension
1/8"10-32, 1/4".219
5/32"1/4", 5/16".250
3/16"1/4", 5/16", 3/8".313
7/32"3/8".375
1/4"5/16", 3/8".375 or .438
5/16"1/2", 5/8".563
3/8"5/8".625
Can I make my framework out of aluminum?

Generally, aluminum is too soft for cable railings. Aluminum and stainless can react and cause electrolysis. If properly insulated and structurally equivelent to the framework described on pg 7 of the catalog, an aluminum framework can be used.

What grade of stainless steel does Johnson Use?

For all major components, Johnson uses Type 316 stainless steel. Type 316 is low-carbon “18-* chromium-nickel stainless steel modified by the addition of molybdeenum, which greatly increases its corrosion resistance.