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View Full Version : bad day at the ramp . . .



Bill Huson
08-15-2011, 08:22 PM
involving my only frozen snot boat (one aluminum, three wood). My frozen snot boat is a 23' walk around cabin Parker with a 250 hp Yamaha on the stern. Rough guesstamite goes around 5,000 lbs plus. So we're hauling it out on the Road King trailer to take her in for a well baby check up. All is well, boat slid up on trailer and bow chain hooked up. I slowly drag boat/trailer up ramp onto the hard . . . and then *PAWANG* the bow chain expodes in itty bitty pieces.

I'm going WTF! That's the safety device to keep the boat on the trailer should the winch strap fail? Then I examine the Road King version of a bow chain which I hadn't checked out before - my bad - it is a 3/16" link chain. A powder puff chain for a 5K boat. The one on my old Cox trailer which hauls my less than 1,500 pound aluminum boat has bigger links. Road King claims that's all they carry in parts - 3/16" chains.

Parker went back in the water and back to the slip, dragged trailer home for some serious modifications. I will say the Road King is a nice trailer, tows well, brakes work well, 2-speed crank winch does the job, but I doubt I buy another one from a company which cheaps out on a critical safety item like a bow chain, considering they cost pocket change compared to the overall trailer cost.

Breakaway
08-15-2011, 11:38 PM
What about the winch cable? Did that let go also?

Bill Huson
08-16-2011, 08:03 AM
What about the winch cable? Did that let go also?

Nope. The 2" wide nylon(?) winch strap held.

Tom Lathrop
08-16-2011, 08:35 AM
Bill,

Maybe the chain didn't break because it is too small. Maybe is is just inferior stuff made in some Chinese back yard like much of the stuff on trailers these days. Some of that metal is so bad it flakes off if you breathe on it. I have some of it on a Magic Tilt Trailer.

Canoez
08-16-2011, 08:43 AM
When sizing a new safety chain, don't forget dynamic load on that 5000 pounds... That could be a big issue.

floatingkiwi
08-16-2011, 09:19 AM
You were blessed to have this not hurt or kill anybody. I would say it was a fortunate thing that happened at the ramp. Cripes, my towball, get that, the actual towball, snapped off my trailer with my dory on it, at the top of a hill on the 101 just before the GG bridge before the tunnel. I heard a series of heavy clunks, then nothing. I looked in the rear view and could see my boat with smoke and sparks flyin around where water does when she is on the water, getting smaller and smaller. I stayed in front of it to protect it from running away down the hill at all and found myself following it slowly toward a dirt bank on the side of the road, where finally, the scraped up hitch found solid ground and she came to a solid thump in a solid manner. Whew. Safe. Great. Right, now what. I backed up and went to the trailer and to my surprise saw a guy getting out of his car who had done the same protective move I had with using his vehicle as a shield, but in the rear. We exchanged a few friendly words, shook hands and I was back on the road in like, two minutes as I had another ball and the tools I needed right there.I think of that guy often. It could easily have been someone less onto it and done something silly or worse.
You know, there has been one time in my life, one time only, I have ever neglected to fit the safety chains to connect the trailer to my truck, should this event take place. And it was then.

Canoeyawl
08-16-2011, 11:04 AM
Proof coil 3/16" PC Chain, 750lb. SWL, (safe working load), Breaking Strength, 3000lb.

Look carefully at the welds on your chain. As a rule of thumb the larger the weld, the stronger the chain.

(You can get 3/16 chain in a 10,000 pound breaking strength. That would be grade 100 -designed for overhead lifting.)

Link (http://www.truckntow.com/productspecs/NACM_Welded_Specs.pdf)

MiddleAgesMan
08-16-2011, 12:35 PM
I don't understand how the chain ever came under stress. The nylon web strap had all the tension, right?

My MagicTilt (bought used) didn't have a chain--just a partial link welded to the tongue to attach something to. Currently I'm just using a doubled length of Spectra braid, intending to upgrade to something or other at some point.

Canoez
08-16-2011, 01:54 PM
Proof coil 3/16" PC Chain, 750lb. SWL, (safe working load), Breaking Strength, 3000lb.

Look carefully at the welds on your chain. As a rule of thumb the larger the weld, the stronger the chain.

(You can get 3/16 chain in a 10,000 pound breaking strength. That would be grade 100 -designed for overhead lifting.)

Link (http://www.truckntow.com/productspecs/NACM_Welded_Specs.pdf)

+1 on the proofed or lifting chain - they're rated. Generally available chain is not.

Bill Huson
08-16-2011, 04:20 PM
I don't understand how the chain ever came under stress. The nylon web strap had all the tension, right?

My MagicTilt (bought used) didn't have a chain--just a partial link welded to the tongue to attach something to. Currently I'm just using a doubled length of Spectra braid, intending to upgrade to something or other at some point.

Web strap fabric will stretch, and under a load as in boat attempting to slide back the coil of web on the drum will tighten. That is what happened, and the dinky little dog chain suitable for medium size dogs only let go.

Bill Huson
08-16-2011, 04:24 PM
Good info. Methinks I'll be going to my fav hardware store and pick up about 5/16" galv chain and the biggest shackles that will fit thru chain. Might it pick up more chain and rig a straight down to the frame bow eye tie down as well. Chain may be involved in transom tie downs as well since none of the ready made ratchet strap transom tie downs I can find are long enough. When I get done if that beast decides to move it will take the trailer with it.

Canoeyawl
08-16-2011, 06:37 PM
Hardware store chain is not very good.
(I'll send you a piece of grade 70 chain if you can't find a short piece - or you can order from mcmaster carr the right stuff)

Bill Huson
08-16-2011, 07:51 PM
Hardware store chain is not very good.
(I'll send you a piece of grade 70 chain if you can't find a short piece - or you can order from mcmaster carr the right stuff)

Depends on the hardware store. I'll check the specs on the stock, but this is a farm, logging, and serious commercial fishing burg so I figure tough chain should be findable.

floatingkiwi
08-17-2011, 11:08 PM
[QUOTE=Canoeyawl;
Look carefully at the welds on your chain. As a rule of thumb the larger the weld, the stronger the chain.

Link (http://www.truckntow.com/productspecs/NACM_Welded_Specs.pdf)[/QUOTE]
Why is this mate? Because the steel is tougher and just needs more welding for a longer time or what?

Canoeyawl
08-18-2011, 12:04 PM
I don't know that the weld is significant by itself, perhaps it may help prevent elongation but it may be just an identifier.
Working with rigging some years back we could usually identify at a glance a "good" chain from a "junk" chain. After a few exciting and costly failures I trained my eye to look at chain very warily. The very best chain had rather elaborate finished welds but I suspect this has changed since Chinese manufacturing prominence. Most chain that I see today will have the grade stamped every few links. The highway patrol insists on grade 70 chain for transport and they will occasionally look and look very carefully if there is an "incident".
Perhaps the weld identifier was only a "branding" technique among manufacturers and now it is mandated that it be stamped with the grade?

The best lifting chain available today is welded from square wire and distinguishable at a glance.

http://www.mcmaster.com/catalog/117/gfx/small/5478tc1s.gif

Canoez
08-18-2011, 12:21 PM
I don't know that the weld is significant by itself, perhaps it may help prevent elongation but it may be just an identifier.
Working with rigging some years back we could usually identify at a glance a "good" chain from a "junk" chain. After a few exciting and costly failures I trained my eye to look at chain very warily. The very best chain had rather elaborate finished welds but I suspect this has changed since Chinese manufacturing prominence. Most chain that I see today will have the grade stamped every few links. The highway patrol insists on grade 70 chain for transport and they will occasionally look and look very carefully if there is an "incident".
Perhaps the weld identifier was only a "branding" technique among manufacturers and now it is mandated that it be stamped with the grade?

The best lifting chain available today is welded from square wire and distinguishable at a glance.

http://www.mcmaster.com/catalog/117/gfx/small/5478tc1s.gif

Grade 120 chain, I believe, no?

Canoeyawl
08-18-2011, 01:55 PM
Yes, grade 120.
We have men working under rigging all the time. It is always a scary deal after you have seen a few failures. Humans are so fragile...
(I like a safety margin of 10x when working under rigging)

Bill Huson
08-18-2011, 08:00 PM
grade 120 or 100 is probably overkill for my purpose, but the 3/16" Road King used is bogus. I think Class I tow safety chains are bigger. I use Class II on my other rig, an aluminum outboard that goes less than 2K with full gas and including trailer, and those links are way bigger. Which reminds me - must replace the "safety" chain on the Road King. RK uses those vinyl coated curly things. A) I do not trust them B) the curly feature is rather annoying when hooking up.

I believe I was the first racer on the east coast to use Arymid (sp?) rope for steering cable on my outboard race boat - yes, race boats still use pulley/cable. The Inspector questioned it `cause the usual cable was vinyl coated stranded steel, and this was OMIGOD! rope. Break strength about 4X steel. Proven by actual test that included the loop thimbles and rope clamps. Maybe I should lash the Parker on with Dyneema !

Canoez
08-18-2011, 10:53 PM
Well, it may be overkill, but remember that the only real difference between using grade 120, 100, 70 or whatever is that you can use smaller chain when using the 120 than with the lower grades.

Gold Rock
08-19-2011, 12:37 AM
Hey Bill, read my comments in this thread: http://forum.woodenboat.com/showthread.php?19757-anchor-chain-quality The number one arbiter of chain quality is it's origin of manufacture. You get what you pay for, but as you've seen, value is relative. There's lots of good info in this thread. I sold welded chain product for many years and know whereof I speak. Enjoy.