ParkLiner owners - how are your saftey chains attached?

[Raz]

Wrapped around the tongue jack and down under uses the tongue jack as a support. The bolt just keeps the chain in place. This let's you replace the chain if need be. Clever. Raz


Edit. Great minds think alike!

[Carol H]

Yes I figured that wrapping it was for additional strength but find it odd that other fiberglass trailers by other manufactures dont seem to do that. Most are like mine either attached under the tongue on one attachment point or attached to the tongue area or frame with two separate attachment points - some welded on some bolted with a single bolt others with u bolted attachements. Actually just went out and double checked my Scamp and sure enough the chains are attached to under the tongue area using one large through bolt but Scamp has welded across the underside of the tongue an extra metal plate thats separate from the top deck of the tongue area and its a little heavier than whats on the top side of the tongue and they have the bolt going through that plate only, not through the top of tongue area or the frame.

Perhaps PL used the wrap around system as you suggest to increase the strength because they didnt reinforce or install anything on the tongue strong enough to hold the bolt?

[Brian M. in NY]

Originally Posted by Carol H

Thanks Brain - as they say a picture is worth a thousand words.

It's actually Brian, but I'll take all the credit I can get.

[frank_a]

Originally Posted by P. Raz

For what it is worth there was a long discussion on drilling holes through trailer frames and the general consensus was that it was a bad idea as it can encourage cracks and eventual frame failure. My chains were simply welded on. I've used three different tow vehicles and have change the chain length using threaded links and more chain. Finally, Frank, a picture of your set up would make it not only clearer for those of us without Parkliners but also for future Parkliner owners reading this thread. Raz

For what it's worth Raz, having been a hobbyist welder for many decades, welding things changes metal characteristics as well. I've drilled lots of holes in trailer frames and never had a crack emanate from one (at least that I know ) or any kind of a failure. Welding something to a trailer frame can also cause problems down the road if not done right, i.e., amperage too high.

Right now a picture of the set-up on our ParkLiner is a no-go, as I have already cut the chain to mount it solidly, which it was not before.

Gee!

Frank

[frank_a]

Originally Posted by Carol H

Yes I figured that wrapping it was for additional strength but find it odd that other fiberglass trailers by other manufactures dont seem to do that. Most are like mine either attached under the tongue on one attachment point or attached to the tongue area or frame with two separate attachment points - some welded on some bolted with a single bolt others with u bolted attachements. Actually just went out and double checked my Scamp and sure enough the chains are attached to under the tongue area using one large through bolt but Scamp has welded across the underside of the tongue an extra metal plate thats separate from the top deck of the tongue area and its a little heavier than whats on the top side of the tongue and they have the bolt going through that plate only, not through the top of tongue area or the frame.

Perhaps PL used the wrap around system as you suggest to increase the strength because they didnt reinforce or install anything on the tongue strong enough to hold the bolt?

Well, by golly, apparently ParkLiner does this straight from the factory. For all the boat and utility trailers I have towed over the decades I have never before seen anything like this, which is why I asked about it. As Carol says, bolted, welded, yes, but wrapped loose around the tongue jack? Hmm.

Frank

[frank_a]

Originally Posted by Brian M. in NY

I went out and took a couple of photos on PL34. The safety chain is attached at the front of the tongue jack with a grade 7 bolt.
Attachment 66181

The chains pass around the back of the jack and cross underneath the "A" frame. If I pull the chain straight forward and measure from the end of the coupler it is about 22 inches.
Attachment 66182

Measuring from the bolt to the end of the chain gives me about 36 inches on each side.
Attachment 66183

I have plenty of slack to reach the attachment loops on the hitch on my Tacoma without having so much that the chain drags on the pavement.

Thanks Brian. Gee, maybe I should just get a longer chain? Mine were a bit too tight for comfort when bringing this trailer home from NJ. Without the slack in the chain around the jack it wouldn't have been a problem. I thought it was just peculiar to #006. I guess not. The other thing is the bolt wasn't holding it down; the chain simply slipped right off the top of the bolt as I unwound it.

Hmm.

Frank

[Carol H]

Originally Posted by Brian M. in NY

It's actually Brian, but I'll take all the credit I can get.

Good lord.... did I ever mention how I really struggle with my little phones screen and no glasses and auto type! At least I have never sent a text to my boss saying I cant come to work because I am at home in bed with a clown! instead of saying a cold!

[Carol H]

Originally Posted by frank_a

The other thing is the bolt wasn't holding it down; the chain simply slipped right off the top of the bolt as I unwound it.

Hmm.

Frank

Well now you know for sure why it was wrapped around everything - added strength
Are you really surprised ?

[Bob Miller]

I saw that, I hope that the jack is guaranteed forever.

"DO NOT DRILL" is a warning usually seen on OTR truck frames. On a trailer, two 3/8" holes, in the top web shouldn't compromise the frame. And welding leaves open the issue with spot heating, bad welds, rust, and the inability to easily change the chain in the future.

[deryk]

I'm at my moms and my setup is like Brian's but only 2 bolts...will post the photo when I get home.

[frank_a]

Originally Posted by Carol H

Well now you know for sure why it was wrapped around everything - added strength
Are you really surprised ?

As a matter of fact Carol, I WAS surprised!

Frank

[frank_a]

Originally Posted by Bob Miller

I saw that, I hope that the jack is guaranteed forever.

"DO NOT DRILL" is a warning usually seen on OTR truck frames. On a trailer, two 3/8" holes, in the top web shouldn't compromise the frame. And welding leaves open the issue with spot heating, bad welds, rust, and the inability to easily change the chain in the future.

Actually I think I will explore two holes per side. I like the idea of using u-bolts for chain attachment. I have not really looked at the frame closely yet, and may not have time before it gets dark on me tonight. I need to stop and see a man about a carport to park the trailer under, then hit the town office where they have left me a building permit application.

I won't be towing this baby anywhere for at least 6 months anyways!

Thanks all.

Frank

[deryk]

Just got home, so here is the promised photo..

[Byron Kinnaman]

After what happened to me a couple years ago I'd be a bit Leary of the ParkLiner lashup for safety chains.

As it so happened the coupler came off the ball and the tongue hit the pavement. I was only going between 5 and 10mph. My Scamp has a short flat piece of steel welded to the frame with hole that has a bolt through to hold the safety chains. The impact bent the steel piece and broke one side of the safety chains. It was no big deal to remove the bolt and replace both bolt and safety chain.

With the PL the chain wrapped around the tongue jack it appears that you could bend the tongue jack to make it unusable. Also you could bend the coupler so that it would take a welder to cut off the coupler and replace that.

In my case a new chain, new bolt, new nut, new washers, and about 5 minutes of work and all repaired. I didn't worry about the bent piece, it still worked just fine. I had thought I might have to have that piece replaced, but that still wouldn't have been very expensive. I was also over 2,000 miles away from home.

Just some things to think about.


P.S. My trailer only weighs 1700 lbs.

[deryk]

I guess another ParkLiner changes but each of my 2 chains is separatly bolted to the frame, so if one bolt failed the other would still be holding... lets see a pic of yours byron

[Ice-breaker]

Originally Posted by deryk

Just got home, so here is the promised photo..

Good photo Deryk. Seems to me from looking at yours that the strength of the bolt and washers is key to your system functioning properly. As a minimum, I would use high strength bolts with thick and much larger diameter washers on them to keep the chain from "popping loose" when under strain.

regards
dave

[Raz]

Originally Posted by Bob Miller

"DO NOT DRILL" is a warning usually seen on OTR truck frames. On a trailer, two 3/8" holes, in the top web shouldn't compromise the frame. And welding leaves open the issue with spot heating, bad welds, rust, and the inability to easily change the chain in the future.

A load on a box beam causes the top to be in compression and the bottom to be in tension with the stresses distributed evenly across the top and bottom. When a hole is drilled, the stress is now concentrated in the remaining area. I would suggest that how big a hole before failure is a question best left to an engineer. But if you think a 3/8" hole is ok, who am I to argue. I couldn't even begin to do that calculation. Take care, Raz

[frank_a]

Originally Posted by P. Raz

A load on a box beam causes the top to be in compression and the bottom to be in tension with the stresses distributed evenly across the top and bottom. When a hole is drilled, the stress is now concentrated in the remaining area. I would suggest that how big a hole before failure is a question best left to an engineer. But if you think a 3/8" hole is ok, who am I to argue. I couldn't even begin to do that calculation. Take care, Raz

Generally what I do for holes through rectangular tubing is weld a round tube in with an i.d. the size of the bolt I want to use. This takes stress off the rectangular tubing. I did that when I built my hot rod chassis years ago. What I am going to do in this case though is set mine up like Deryk's. I may do it a bit different, but similar. Pics when it gets done.

Thanks!

Frank

[Byron Kinnaman]

Originally Posted by deryk

I guess another ParkLiner changes but each of my 2 chains is separatly bolted to the frame, so if one bolt failed the other would still be holding... lets see a pic of yours byron

I thought about your request, and decided that wasn't the intention of my post to say that my set is the best or proper or ??
What I'm suggesting is that you look at how the chain is attached and if coupler should come off the ball and dig into the pavement whats gong to happen when the end of the chains are hit. What can be damaged and how difficult would it be to move the trailer or fix if that should happen.

What you do is up to you.

[Donna D.]

Originally Posted by frank_a

....I've drilled lots of holes in trailer frames and never had a crack emanate from one (at least that I know) or any kind of a failure. .

It can happen! Here's a link to a cracked frame on a Casita due to drilled holes in the frame. Those of you that aren't members of CasitaForum won't be able to view the thread. http://www.casitaforum.com/invboard/...n-frame-drama/

You make your decisions, you take your chances. Knowledge is power!