Need Assistance with Langmuir Crossfire Pro Assembly – Length of Lower Cross Tubes

I am currently in the process of assembling my Langmuir Crossfire Pro, and I have run into an issue that I hope someone in this forum could assist me with.

My main difficulty lies in aligning the Lower Rail Tubes perpendicular to the Lower Cross Tubes. When I measured the lengths of the Lower Cross Tubes, I found a discrepancy between the two tubes. One tube measures approximately 61.7 inches (156.7 cm) while the other is about 62.64 inches (159.1 cm). I’m under the impression that these tubes should be of the same length. I have tried mounting them both ways - with each tube at the front and the back - but I continue to see misalignment.

I am wondering if this discrepancy in length might be the root cause of my issue. Can anyone advise me on what the correct length of the Lower Cross Tube should be? Also, in the case that the tubes are of differing lengths, which one should be installed where?

Any help or advice on this would be greatly appreciated! I’m eager to get my equipment assembled correctly and put it to use.

Thank you in advance for your assistance.

Welcome to the forum!

Yes, the lower cross tubes are the same length and as best as I can remember from when I assembled mine they should be interchangeable. I remember reading of at least one instance where tubes were shipped that were the wrong length, although for the life of me I can’t remember which tubes that person was having problems with.

Contact @langmuirsystems, they should be able to give a definitive answer as well as assist you in rectifying any problems.

1 Like

The holes should look like this when placed side by side and the distance between them consistent:

And the four holes need to create a perfect parallelogram (eventually a perfect rectangle):

If that is not possible, something is wrong.

1 Like