Strand Chuck FAQs

Q. Is it ok to mix different brands of chucks?
A. Absolutely not, no way! Different brands should never be mixed. The different components may look like they will fit to the naked eye, however, differences in design of each piece can cause the assembled chuck to malfunction or fail. If your plant ever changes brands of chucks, it is very important that you remove all of the old brand chucks and components from your plant before you start using a new brand of chuck.

Q. Can I use PAUL Multiple Use Chucks on epoxy coated strand or carbon fiber rod?
A. No, PAUL chucks cannot be used on epoxy coated strand unless all of the epoxy coating is removed from the jaw biting area. Gripping carbon fiber rod with a multiple use chuck will not work. High strength glues or epoxies have been used to bond carbon fiber rod.

Q. Can I use PAUL ½” Multiple Use Chucks on ½” “Special” strand?
A. Yes, you can. “Special” means nominally oversized or undersized strand and the PAUL ½” strand chuck will grip up to .519” and as low as .492”. .

Q. How many uses can I get from my chucks and jaws?
A. That is hard to answer due to the great number of variables involved during the life of the chuck or jaw. Of course, maintaining your chucks is critical. Cleaning and lubricating will greatly increase the life of your chucks. Things like shock loading, uneven stressing surfaces, stressing without a cap and hitting the chuck with a hard object such as a hammer or rebar will, of course, decrease the life of your chucks and jaws. Depending on the type of stressing operation and the proper use of the strand chucks, you should expect over 300 uses from your jaws and several thousand from the bodies. Items such as retaining rings, springs and caps will also wear and have to be replaced as needed.

Q. Can I use a Multiple Use Anchor Chuck on the jacking end?
A. In most cases no. The chucks on the jacking end should have a cap and spring. The spring puts equal pressure on the 3 jaw segments while the strand is pulled through and the cap acts as a stressing plate. Without the spring, the jaw segments could seat unevenly causing a strand failure. Since the Multiple Use Anchor Chucks have no cap or spring , you would be jacking directly on the jaws which would end up breaking . They should only be used on the non-jacking end.

Q. Is it ok to stress against a chuck without a cap?
A. See above answer, Attempting to stress against a chuck without a cap could damage the chuck body making it impossible to attach a cap. You also increase your chances of having misaligned jaws.

Q. How often do I need to clean, inspect and lubricate my chucks?
A. After every use you should first clean the bodies and jaws of any contaminates such as form oil, concrete slurry, grease, dirt, etc. Next you should inspect the bodies for damage or deformation. Check the jaws for worn teeth or cracking. Check the cap attachment points for damage or deformation. Make sure the springs are good and not worn out. The retaining rings should be inspected for shredding or tears. Any worn out of damaged components should be thrown out and replaced. It is very important to lubricate the outside of the jaw assembly and the inside of the body before re-assembling. Note, some lubricants may require a drying period before re-assembly. Be sure to read the lubricant instructions before use.

Q. Why are my chucks sticking on the strand?
A. See Question #7. The most common reason chucks stick is lack of lubrication or the wrong kind of lubricant. If there is not enough lubricant, the bodies and jaws are compressed together metal-to-metal. If the wrong kind of lubricant is used, it may act like a glue under compressive force creating a bigger problem. Another reason chucks stick is damage. When the bodies have been stuck with a hard object, it can damage the body. Then under load, the jaws become lodged. The only remedy is to dispose of the damaged bodies and replace them.

Q. Is it safe to knock a chuck loose with a hard object?
A. No. Striking a strand chuck with a hard object such as a hammer, rebar or chunk of concrete could damage the chuck body or cap making it even harder to get off the strand the next time. This cycle will continue until the chuck is totally useless. We recommend that you cut the strand off with the chuck attached and place the strand in a vise. Using a chuck removal tool and sliding hammer, the jaws can be safely disengaged with no damage to the chuck.

Q. Is it safe to use a damaged chuck body?
A. It may not be! Small dings and scratches will cause no harm. If you have a body that has been deformed “mushroomed” or has deep dents and strike marks, there may be an accident waiting to happen. If the chuck body is struck with enough force to create a heavy dent, the metallurgical strength of the body could be compromised. Hit the chuck several times and you have the potential for that body to crack or explode. You just never know when! Would you ever strike a live hand grenade with a hammer?

Q. Can I use a tumbler to clean my bodies and jaws?
A. Yes you can. In fact, tumblers and vibratory cleaners make wonderful cleaning methods as long as you follow one simple rule. Never use a hard media such as ceramic beads, glass beads, sand, etc. The hard media will wear on your components. Use only natural media such as walnut or pecan shell or ground corn husk. While the chucks are cleaning, your chuck maintenance man can be tending to other tasks.

Q. What can I use to clean my chucks?
A. See Question #12. We offer jaw and body brushes. Brushes should be mounted in a stationary drill motor. The bodies and jaws can be pressed on to brushes as the drill runs. Soaking the chuck components in liquid solvents may also work, however, EPA regulations may not allow this method.

Q. Why are my jaws cracking?
A. If your jaws are old and had several hundred uses they may just be worn out. However, if your jaws are new or had very few uses, then there may be a problem during your stressing. Many times cracked jaws are a result of shock loading the chucks and jaw offset. Shock loading occurs when the strand is suddenly released by the jack and the chuck attempts to instantly grab. Using an ease-off function or slow load transfer will eliminate shock loading. Jaw offset occurs when 1 or 2 of the 3 jaw segments will move farther down into the body than the other jaw segments resulting in uneven loading in the chuck body. The most common reasons for jaw offset include missing brands of chuck components. Old or worn out springs, lack of lubrication, or stressing abutments that are not smooth and flat may be a factors as well.

Q. Can I use a splice chuck to connect different size strands?
A. Yes. We offer a reducer coupler allowing different size splice chuck bodies to be used.