Paracord is a form of kernmantle cord that was originally developed for use with parachutes. Paracord is typically made of nylon and true parachute paracord is made to a very specific set of standards. However, these days paracord is used for a wide range of applications and made from a variety of synthetic materials. Paracord has become a name for a type of rope made in a certain style, and does not necessarily mean that any given variety of paracord is suitable for use with a parachute!
There is great debate about which types of paracord are suitable for whipmaking; genuine (commercial spec) 550 paracord and MIL SPEC 550 paracord and 650 paracord and PET paracord. It can be very confusing (this blog may help, there is lots of info). There are a great many fibres that used for different varieties of paracord, but this discussion centres around what are probably the two most well known forms – nylon and polyethylene terephthalte (PET).
Always bare in mind that paracord was originally designed to keep people alive when using a parachute! Some of the features necessary for reliable parachute paracord are not needed for whipmaking, and so one shouldn’t fall into the trap of assuming that the best parachute cord makes the best whipmaking paracord.
The main differences:
- 550 MIL SPEC paracord – 550 lbs breaking strain, nylon, 7 strand core with each strand made of 3 twisted strands (made to a precise military specification)
- 550 Commercial paracord – 550 lbs breaking strain, nylon, 7 strand core, designed for non-critical applications
- 650 paracord – 350 lbs breaking strain, nylon, 4 strand core
- PET (polyethylene terephthalte) commercial paracord – breaking strain varies (but remains high), polyester, 7 strand core, designed for non-critical applications
The main difference between the construction of these cords is with the inner strands; the number of strands, the weight (denier) of the strands, the way they are twisted together and the construction of the strands…
These differences in the core are irrelevant when making whips as you are hardly going to throw yourself out of a plane, with a whip between you and a grisly end, hoping your whip doesn’t break… and anyway, all the inner strands are removed before plaiting most whips (our coyote whip retains the inner core).
PET is widely used to make commercial grade paracord, and is a polyester (as opposed to nylon) thermoplastic. While we wouldn’t make a parachute with it, it is still a very strong cord that in our view is more than suitable for whipmaking. The product can vary by manufacturer and there are some very shoddy cords available but there are also some excellent PET cords out there – it’s all about finding a reliable supplier of quality cord.
While both nylon and polyethylene terephthalte are plastics, there are some key differences between them in terms of how suitable they are for various applications.
- good chemical resistance (except alkalis)
- excellent ultra-violet light resistance
- less elastic than nylon
- extremely low water absorption
- excellent dimensional stability
- very low creep (i.e. permanent deformation when under stress)
- excellent abrasion resistance and very good wear properties
- high strength
- relatively high density
- rot and mildew resistant
- moderate UV resistance (degrades if left in direct sunlight)
- higher elasticity than PET
- hygroscopic (attracts and absorbs water) leading to degradation
- good chemical resistance (except acids & alcohols)
- good resistance to greases and oils
- higher creep than PET
- good abrasion resistance
- excellent strength
- relatively high density
Some applications for PET ropes and fibres – helicopter lifting slings, sailing halyards, antenna support ropes, static climbing ropes, guy ropes, tow ropes, seatbelts, sails, Dacron cord (also used for whipmaking)
Some applications for nylon ropes and fibres – dynamic climbing ropes, parachutes and parachute cords, mooring lines (small vessels), ropes in pulleys and winches, musical instrument strings
We feel that PET paracord is great for use in synthetic whip construction. It is a strong, light cord that doesn’t unduly ‘creep’ under stress, and which is excellent for use outdoors due to it’s high chemical, UV and water resistance. PET is not as strong as nylon, but is plenty strong enough for use in a whip and has excellent wear and abrasion resistance. As PET is less stretchy than nylon, there is more energy transfer from the pommel of the whip to the cracker, giving a cleaner throw. Nylon cords are also great for synthetic whipmaking but are arguably not as suited to outdoor use and while stronger than PET, nylon cords (and thus nylon whips) are more likely to permanently stretch with use.
And PET paracord is available in a great many colours including glow-in-the-dark variants, camouflage colours, multi-coloured and reflective, compared to nylon 550/650 paracord which have more limited colour availability (especially compared to MIL SPEC 550). We also find PET is a softer cord that is less likely to cause friction burns so it doesn’t chafe your hands as much when using a whip for extended periods (also helps while making them!).