Rescue 42 Offers a Best Practice Tip for Strut Tube Overlap
Chico, CA -- People often ask us if the struts are any stronger if you start pulling out the white tube before the blue section is completely extended? The answer is no, and doing this could cause you some headaches during an extrication.
The struts are designed to be deployed in the following manner: after removing the yellow pins, pull up on the combi-head, exposing the blue tube. Continue pulling the blue tube out until a) you have enough strut to stabilize your vehicle or b) the interlock on the blue tube engages and begins to pull the white tube out of the red. When the first white tube hole emerges from the red tube, place a yellow strut pin through it to lock the blue and white sections. Continue pulling out the white until a) you have enough strut to stabilize or b) the interlock on the white tube engages and you've reached the maximum extension of the strut. Do not pull too hard or the white tube interlock will bend (by design) to protect the strut. When you have extended enough strut, place the second yellow strut pin through the top hole in the red section.
All of our load testing is based off of the blue coming out first, then the white. You can of course "out think" the system by pushing the blue tube back inside the extended white, however, there are some very good reasons not to do this. First off, it doesn't give the struts any added strength (we could get into the physics of this one, but please just trust our math) however, the biggest problem is that you may not be able to use the Strut Jack and we'll explain why.
The holes on the TeleCrib system are approximately 1" in diameter, and so are the pins (both yellow composite and steel base pins). There is very little 'slop' in the system. When the struts are engaged with a load, any section of the strut with tube overlap will have a little bit of compression overlap on the holes (as seen in the photo). Though slight, it's just enough that you will not be able to force a pin through those holes. So if you're hoping to use a Strut Jack, you will not be able to pin the jack to the strut sections with overlap. If deployed correctly, this is only going to be a problem with the top 6" section (the top three holes) on the white tube (the safety overlap). By using the pinned manual extension on the strut jack you can easily work around these three holes. If you force the blue strut section back into the white, you've eliminated ALL the holes on the white once it's under load.
For more information on using the TeleCrib Strut System, please review the FREE instructional DVD and your TeleCrib Owner's Manual. If you have any questions, give us a ring, toll free at (888) 427-3728.