Bad start to season: Broken mast

[mastreb]

I'm satisfied with your original estimate, with your math, and with the successful experiment. Clearly for the conditions you had to deal with, the transport was safe. As with any time one travels on a road, a fair modicum of risk was inherent.

Before engaging in any kind of argument (and I mean merely difference of opinion, not angry rant) I ask myself, and occasionally the other person this simple question: "What evidence can you imagine that could convince you that you are not correct?"

If they can't come up with an answer to that question, then there's literally no point in engaging in a discussion.

[DaveB]

Bob,
You manage to get the job done, all I am saying is for the avarage person not to try this. Sorry this went this far and hope others that may consider doing this has the knowledge to do so.I might add that at the beginning there was no mention of your Enginnering degree and the detail discription on how you did it.
I designing and stabilizing structures for buildings, stageing on a tempory support structures. Why I mentioned your Mast Travel.
In Florida the overhang of the car would have well exceded the Limits and you would have been stoped and ticketed and told you cannnot go further.
Safe Sailing,
Dave

Really guys???

My Rav 4 is equipped with pneumatic tires, springs, and shock absorbers. These do a pretty good job of smoothing out the bumps in the road and keep the dynamic forces on the sprung mass of the vehicle usually well under 1 extra g, easily under 3 g's. If I were to hit a bump capable to transmit 5 g's to the sprung mass, the suspension would likely bottom out. 10-20 g's we would be talking about popping tires, passengers getting injured, breaking the engine mounts etc.

Interstate 90 is a pretty smooth ride between Seattle and Moses Lake. The way you gus are talking, you would think that I was suggesting taking the mast on a cross country race in Baja California.

if you are worried about road forces on your masts while towing your boats, look at installing an extra mast crutch to help support the 20' unsupported span.

Yes, I did not calculate the stresses prior to hauling the mast. Knowing that Seapup was successful I believed that I could do this also.

Prior to leaving BWY I applied practical engineering judgment. I looked at the deflection prior to strapping it, I tightened it enough so it was tight, but not too tight. Rotation was restrained by lines (hard to see in pic) that go from the front of the roof rack to the mast in the same plane as the mast. I tugged here and there and felt comfortable that it was rigged well enough.

I have never suggested that this is the best possible way to transport a mast, only that it is good enough.

Calculations were done only after it was suggested that this was reckless or otherwise unsafe. I stand by my decision. Looks like we are going to have to agree to disagree.

Bottom line: tune your rigging so that your mast is properly supported to prevent breakge while sailing with strong winds.

Happy Sailing,

Bob

[Catigale]

Thanks to both of you for keeping the discussion civil engineering.....

[RJG 26S]

A few more comments/unanswered questions from previous posts:

1. The mast was mostly pre-drilled, for the larger bolts. The smaller ones for the main halyard block, spreader bar base and a few other things are not.

2. Ikea trip: no major purchases, just a few small items for the kitchen. Not a whole lot of money to spare after dropping over a grand at BWY. The Admiral was not too thrilled about the 6 hours in the car just to purchase parts for my "mistress" so I offered her the side trip. Moses Lake is very limited for shopping. If anyone out there wants to open a Target here, my wife would do her share to support it.

3. Dave, no hard feelings. I understand your point.

4. Interesting that we passed no fewer than 4 Washington State Troopers and they did not seem to be concerned with the projection on my Toyota. No doubt they were looking for someone going 6 over the speed limit or someone talking on their cell phone.

5. And finally, this is me:



Bob