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Actual Weights as measured

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Topic: Actual Weights as measured
Posted By: Pod People
Subject: Actual Weights as measured
Date Posted: 02 Oct 2019 at 8:03pm

We recently returned from a 2 week trip with our 179.  Before we left, I went to our local county dump and recycle center and weighed our rig.

We have a 2012 Ford Expedion EL tow vehicle with a full tank of gas, 2 people, a canoe on the roof   and "stuff".  the Rpod is a 2015 179 and stocked with normal food, clothes and gear as usual for a 2 week trip. The tongue has a single full propane tank, 2 GC-2 batteries, the spare tire and a manual tongue jack. There are 2 bikes on a bike rack (total of 86 #) at the rear of the pod and 15 gallons (120#) in the fresh water tank at the front of the pod.

Here are the actual weights:

 1-Truck with 179 RPod attached, weight distribution engaged but Rpod not on scales(so I think this includes the actual tongue weight as well as the truck weight)    7340#

2-truck and RPod on scales together w/ WD engaged     10820#

3-truck only (we disconnected the RPod and left it on street) includes wd hitch weight   6800#

4- tongue weight (#1-#3)    540#

5- Trailer weight  (#2-#3)   4020#

6- trailer axle weight  (#5-#4)     3480#

 per factory sticker affixed to RPod             

RPod weight 2785#

RPod carrying capacity  983#

Total maximum weight    3768#

 

So, obviously I am overweight in the RPod by 4020-3768=252#

I can easily leave the 120# water out, but still 130# overweight.

I also realize that we have a 3000# axle, so I am also overweight on the axle by 480#

 

This is interesting and I would like to hear how other podders interpret these actual weights. Perhaps I am wrong.  Does this seem right?  I did not think to weigh the rig without wd engaged, but I’m not really sure how that would affect the weights.

 Thanks for your insights and thoughts.

Vann

 

 

 



-------------

Vann & Laura 2015 RPod 179
https://postimg.cc/0zwKrfB9">



Replies:
Posted By: offgrid
Date Posted: 03 Oct 2019 at 4:30am
I think your measurements 2 and 3 (and calculation 5) are correct, but I think you probably need to redo measurement 1 without the wdh tensioned. By leaving it tensioned there is extra weight moved to the trailer axle so your tongue weight might possibly be even higher. The other thing that happens is that unless your scales are perfectly level with the pavement on each end the wdh will throw off the measurements a little when part of the rig is on the scales and part isn't because it is trying to level up the rig. 

I've found the best way is to leave the wdh untensioned and add each axle onto the scales one at a time, that way you can directly get the load on each axle, which is in the end what you need to limit and balance out anyway. 

That being said, none of your trailer numbers are a whole lot different for mine (also 2015 179 with 2 GC2's and one propane). I have no bike rack but I regularly completely fill my fresh water tank, and minimize any other stuff in the trailer that I can. IIRC I was about 3850 on the trailer, 3300 on the trailer axle, and 550 on the tongue. The axles are nominally good for 3500 (not 3000) but I reinforced mine anyway. The wdh increases the trailer axle load on my rig by about 120 lbs, so I'm really close with it tensioned. 


-------------
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold


Posted By: Olddawgsrule
Date Posted: 03 Oct 2019 at 6:51am
Originally posted by Pod People

We recently returned from a 2 week trip with our 179.  Before we left, I went to our local county dump and recycle center and weighed our rig.

We have a 2012 Ford Expedion EL tow vehicle with a full tank of gas, 2 people, a canoe on the roof   and "stuff".  the Rpod is a 2015 179 and stocked with normal food, clothes and gear as usual for a 2 week trip. The tongue has a single full propane tank, 2 GC-2 batteries, the spare tire and a manual tongue jack. There are 2 bikes on a bike rack (total of 86 #) at the rear of the pod and 15 gallons (120#) in the fresh water tank at the front of the pod.

Here are the actual weights:

 1-Truck with 179 RPod attached, weight distribution engaged but Rpod not on scales(so I think this includes the actual tongue weight as well as the truck weight)    7340#

2-truck and RPod on scales together w/ WD engaged     10820#

3-truck only (we disconnected the RPod and left it on street) includes wd hitch weight   6800#

4- tongue weight (#1-#3)    540#

5- Trailer weight  (#2-#3)   4020#

6- trailer axle weight  (#5-#4)     3480#

 per factory sticker affixed to RPod             

RPod weight 2785#

RPod carrying capacity  983#

Total maximum weight    3768#

 

So, obviously I am overweight in the RPod by 4020-3768=252#

I can easily leave the 120# water out, but still 130# overweight.

I also realize that we have a 3000# axle, so I am also overweight on the axle by 480#

 

This is interesting and I would like to hear how other podders interpret these actual weights. Perhaps I am wrong.  Does this seem right?  I did not think to weigh the rig without wd engaged, but I’m not really sure how that would affect the weights.

 Thanks for your insights and thoughts.

Vann


 1-Truck with 179 RPod attached, weight distribution engaged but Rpod not on scales(so I think this includes the actual tongue weight as well as the truck weight)    7340#

I caught this as well. Dis-engage the WDH, you have additional distributed weigh read.

4- tongue weight (#1-#3)    540#

So that makes this number also high. 

I'm 3200#'s on my axle and 385#'s on my tongue. Puts me at 3350#'s (aprox IIRC) with WDH on the axle. I carry only a few gallons of fresh and empty black/gray when traveling to keep the weight down.

What year is your trailer? I didn't know any had a 3000# axle..



-------------
https://www.youtube.com/channel/UCJduGeZNFgtptH67leItRFQ - Byways no Highways
2017 Tacoma
http://tnttt.com/viewtopic.php?f=55&t=72408 - Truck Camper Build
2004 F150 My Overlander


Posted By: offgrid
Date Posted: 05 Oct 2019 at 7:38am
Originally posted by Olddawgsrule

 

4- tongue weight (#1-#3)    540#

So that makes this number also high. 

I'm 3200#'s on my axle and 385#'s on my tongue. Puts me at 3350#'s (aprox IIRC) with WDH on the axle. I carry only a few gallons of fresh and empty black/gray when traveling to keep the weight down.

What year is your trailer? I didn't know any had a 3000# axle..


Since tongue weight is being calculated by subtracting the truck weight without the pod attached (#3) from the truck weight with it attached (#1) having the wdh engaged for #1 (which moves some weight to the trailer axle) should make the tongue weight reading appear too low, not too high. 

Reducing the "average" effective tongue weight by moving some to the trailer axle and some to the front axle is after all the point of having a wdh.  It is hard to get an accurate measurement of the effect of the wdh directly on scales though because its action depends on having all three axles on an exactly flat surface. Any bump, berm or swale will effect the measurement. Which is why a wdh isn't really considered to reduce tongue weight, the TV still has to be able to handle the full tongue weight when the TV rear axle is sitting a bit high and the tension on the WDH bars is reduced or eliminated completely. 

I have the same year 179 as Pod People and it has a 3500 lb rated axle, as do all the heavier rPods. The lighter ones have axles rated at 3000 lb, but it appears to me that this is because FR has had  3500 lbs axles derated to 3000 lbs on those so that they can claim a lower gross trailer weight for the lighter pods. As near as I can tell they are physically the same 3500lb axles. 




-------------
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold


Posted By: Happy Tripping
Date Posted: 05 Oct 2019 at 9:35am

[/QUOTE] I have the same year 179 as Pod People and it has a 3500 lb rated axle, as do all the heavier rPods. The lighter ones have axles rated at 3000 lb, but it appears to me that this is because FR has had  3500 lbs axles derated to 3000 lbs on those so that they can claim a lower gross trailer weight for the lighter pods. As near as I can tell they are physically the same 3500lb axles. [/QUOTE]


Perhaps the one thing that most upsets me about Forest River is their 'Heads I win, tails you lose' attitude, exemplified by their response to possible damage from someone standing on the roof of the trailer and their response to me when my axle fell off.

If I understand the issue, and I am not an expert, the 3500# and 3000# axles are indeed physically the same. The difference is in the rubber gizmos that connect the axles to the frame, do the actual work, and that therefore define the rating, the result - the 3000# limit being indeed lighter. 

It would be nice if Lippert/Dexter/Forest River would address this but I am afraid that their lawyers don't permit this.


Posted By: offgrid
Date Posted: 05 Oct 2019 at 10:21am
Originally posted by Happy Tripping




If I understand the issue, and I am not an expert, the 3500# and 3000# axles are indeed physically the same. The difference is in the rubber gizmos that connect the axles to the frame, do the actual work, and that therefore define the rating, the result - the 3000# limit being indeed lighter. 


From comparing model numbers I personally doubt that there is any physical difference at all between the two axles.  It is most likely simply specsmanship in the form of a label change. While overrating an axle has consequences for a manufacturer, there is no rule that says that a manufacturer can't derate an axle. Since the gross trailer weight is defined by the DOT to be no higher than the lowest listed tongue weight plus the rated trailer axle weight, derating the axle to 3000 lbs on some models creates a marketing advantage by lowering the GTW to within the limits of some smaller SUV's. 

Manufacturers of all kinds of stuff do this kind of thing all the time. Its cheaper to make all the products the same and adjust the specs downward on some products to differentiate models within product lines. That way they save cost overall by streamlining the manufacturing process while still being able to get better margins from folks who want the "high end" model.  That's why it can often be a great deal to buy a cheaper, lower spec'd model rather than the top end. You often get the exact same product at a lower price that way. Misleading? Yes. Unlawful? Not at all, the manufacturer isn't exaggerating the capabilities of the product, quite the contrary. 


-------------
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold


Posted By: Olddawgsrule
Date Posted: 05 Oct 2019 at 3:11pm
Originally posted by Happy Tripping



If I understand the issue, and I am not an expert, the 3500# and 3000# axles are indeed physically the same. The difference is in the rubber gizmos that connect the axles to the frame, do the actual work, and that therefore define the rating, the result - the 3000# limit being indeed lighter. 


My mind goes to what the sticker on the axle states. It comes down to that and not to exceed. 


-------------
https://www.youtube.com/channel/UCJduGeZNFgtptH67leItRFQ - Byways no Highways
2017 Tacoma
http://tnttt.com/viewtopic.php?f=55&t=72408 - Truck Camper Build
2004 F150 My Overlander


Posted By: Olddawgsrule
Date Posted: 05 Oct 2019 at 3:22pm
Originally posted by offgrid


Since tongue weight is being calculated by subtracting the truck weight without the pod attached (#3) from the truck weight with it attached (#1) having the wdh engaged for #1 (which moves some weight to the trailer axle) should make the tongue weight reading appear too low, not too high. 

Reducing the "average" effective tongue weight by moving some to the trailer axle and some to the front axle is after all the point of having a wdh.  It is hard to get an accurate measurement of the effect of the wdh directly on scales though because its action depends on having all three axles on an exactly flat surface. Any bump, berm or swale will effect the measurement. Which is why a wdh isn't really considered to reduce tongue weight, the TV still has to be able to handle the full tongue weight when the TV rear axle is sitting a bit high and the tension on the WDH bars is reduced or eliminated completely. 

I understand what your saying. The whole idea and physic's about weight distribution is still something I'm learning about and wether or not it's better than re-enforcing your TV is better, if your TV is capable. 

For some, there's no choice. For some, even WDH will not work. I jumped pretty quick due to costs and not understanding. I wanted sway control and cost of a WDH with sway made sense at the time. I'm debating that decision now. 



-------------
https://www.youtube.com/channel/UCJduGeZNFgtptH67leItRFQ - Byways no Highways
2017 Tacoma
http://tnttt.com/viewtopic.php?f=55&t=72408 - Truck Camper Build
2004 F150 My Overlander


Posted By: offgrid
Date Posted: 05 Oct 2019 at 5:05pm
I’m right at the upper limit for tongue weight on my TV, so a wdh is for me pretty much essential. I’m looking forward to removing the dual lead acid batteries and placing a lithium battery further aft, thereby reducing tongue weight. After your frame issues, I’m also thinking about frame reinforcement as well. I think an rpod with a 2x4 tube in the axle area, plus a 5200 lb rated axle, and some additional frame reinforcement under the A frame extending from in front of the wdh attachment to a couple of feet aft of the front of the trailer box would make for a pretty robust boondocking trailer at a relatively low cost. The area around the wdh attachment and the front of the box also theoretically gets some high frame loads.

-------------
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold


Posted By: Jeepinator
Date Posted: 05 Oct 2019 at 6:50pm
Given all the smart people on this thread, I’d like to add another element. What is the underlying risk of exceeding tongue weight and will air bags reduce it?  I’ve not determined my exact tongue weight yet but I suspect I exceed the 350# even with the WDH. 

I am aware that sway and receiver/coupler damage are potential risk factors but I assume there are others. 

The TV and trailer are level when the WDH is engaged. 


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2018 Jeep Wrangler Willys
2017 179


Posted By: GlueGuy
Date Posted: 05 Oct 2019 at 7:58pm
Originally posted by Jeepinator

Given all the smart people on this thread, I’d like to add another element. What is the underlying risk of exceeding tongue weight and will air bags reduce it?  I’ve not determined my exact tongue weight yet but I suspect I exceed the 350# even with the WDH. 

I am aware that sway and receiver/coupler damage are potential risk factors but I assume there are others. 

The TV and trailer are level when the WDH is engaged.
The WDH does not reduce the tongue weight, it distributes the weight. Effectively it will reduce the amount of the tongue weight applied to the rear axle of the TV, and distributes it to the front axle of the TV and back to the trailer axle. The amount that goes to each axle depends on the torque plus the length of the moment arms.

Also, air bags will not reduce the tongue weight. Air bags will increase the weight that your rear suspension can handle, but will not increase the weight the axle/bearings can handle or the weight the frame of the vehicle will handle.


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bp
2017 R-Pod 179 Hood River
2015 Ford F150 SuperCrew 4WD 3.5L Ecoboost


Posted By: Olddawgsrule
Date Posted: 06 Oct 2019 at 8:33am
Originally posted by GlueGuy

 The WDH does not reduce the tongue weight, it distributes the weight. Effectively it will reduce the amount of the tongue weight applied to the rear axle of the TV, and distributes it to the front axle of the TV and back to the trailer axle. The amount that goes to each axle depends on the torque plus the length of the moment arms.

I watched yet another pretty good explanation of how WDH's work. To me there is still a bit of magic in this thing..

Even he states the weight on the ball remains, yet transfers/distributes the weight/torque. Magic I tell ya! It's gone, yet still there..
I like how he explains the action of torque the WDH does to compensate (?) the effect. So it's easier to understand why the weight remains, but the effect changes. Still say there's a bit of magic there..

Now he talked of the ball using most of this effect. I tend to wonder how much of this torque is also placed upon our hitch frame. Those of us that have, know how much pressure is on the WDH bars. For example only; if 200#'s are sent forward and 100#'s sent aft, then is the torque applied to the ball/tongue frame equal to that distribution? Or in order for the magic to happen, is it indeed greater..

Here's the video. He's informative and quite a kick to watch!  http://www.youtube.com/watch?v=kCgRiVNaXFc - http://www.youtube.com/watch?v=kCgRiVNaXFc


-------------
https://www.youtube.com/channel/UCJduGeZNFgtptH67leItRFQ - Byways no Highways
2017 Tacoma
http://tnttt.com/viewtopic.php?f=55&t=72408 - Truck Camper Build
2004 F150 My Overlander


Posted By: David and Danette
Date Posted: 06 Oct 2019 at 12:42pm
  The way the WDH was explained to me which made sense to me is that the WDH works like a bridge. The camper axle as one shoreline and the tow vehicle front axle being the other shoreline. The tongue weight is supported at the center of the bridge. Does that make sense.

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2018 Vista Cruiser 19BFD (2018-              
2012 Vibe 6503 (2014-2019)
2009 r-pod 171 (2009-2014)
Middle Tn
2014 Ram 1500 Quad cab




Posted By: Olddawgsrule
Date Posted: 06 Oct 2019 at 3:32pm
Originally posted by David and Danette

  The way the WDH was explained to me which made sense to me is that the WDH works like a bridge. The camper axle as one shoreline and the tow vehicle front axle being the other shoreline. The tongue weight is supported at the center of the bridge. Does that make sense.

Still think there's magic involved! LOL

I've come to a point of understanding the basic principles involved. Torque is something I get. The video and the way he does it, helped quite bit. To me it's how much force is being applied on on tongue frames to accomplish the feat (magic). 

The video is worth a watch and at one point he talks about what 'we' drive through and the added torque/force (?) that is applied. My questions are not if WDH (which he calls Load leveling and like that better) is good or bad.. It's what effect and how to compensate for. 
When my trailer comes back, I will re-enforce the tongue frame. I do believe there's more happening there then 'we' believe there is and worth the expense/effort.
At least the conversation of..

I'm always open to learning.





-------------
https://www.youtube.com/channel/UCJduGeZNFgtptH67leItRFQ - Byways no Highways
2017 Tacoma
http://tnttt.com/viewtopic.php?f=55&t=72408 - Truck Camper Build
2004 F150 My Overlander


Posted By: offgrid
Date Posted: 08 Oct 2019 at 5:47am
Originally posted by David and Danette

  The way the WDH was explained to me which made sense to me is that the WDH works like a bridge. The camper axle as one shoreline and the tow vehicle front axle being the other shoreline. The tongue weight is supported at the center of the bridge. Does that make sense.

That's a good start, except that both TV axles are on the shoreline and we're trying to get more weight on the front axle and less on the rear because the rear one is on the edge of the cliff. Now, let's say the bridge contractor bought his bridge beams too short but still wants to use them so he puts a bolt through them and connects them at a center pivot point. Then to keep the whole thing from falling down he adds a spring between the two beams in the center holding them up. That's pretty close to what a wdh does. 


-------------
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold


Posted By: offgrid
Date Posted: 08 Oct 2019 at 5:57am
Originally posted by Olddawgsrule

When my trailer comes back, I will re-enforce the tongue frame. I do believe there's more happening there then 'we' believe there is and worth the expense/effort.
At least the conversation of..

I'm always open to learning.


There is for sure more load being applied there by the wdh spring bars pulling down. Not to mention the dual batteries etc.  Even without the wdh and batts, there is a high load stress location on the trailer frame a bit under the front of the box. Its not as high as the spot just behind the axle but it's there. So reinforcement in that general area isn't a bad idea. It would probably be better not to lose too much clearance at that point so a 2 inch tube might work better than a 4 inch one which would be the way I think I'd go in the axle area. 


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1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold


Posted By: Pod People
Date Posted: 08 Oct 2019 at 8:04am
I understand what Offgrid is saying. We have a 4x8 utility trailer that had a failure where the tongue met the body. It was a single 3x3 beam and not an A frame, so it had only a single point of connection.  Welding a reinforcement beam under the original beam and adding triangle gussets took care of the issue.
with the RPods A frame, at least there are 2 connection points.
Vann


-------------

Vann & Laura 2015 RPod 179
https://postimg.cc/0zwKrfB9">


Posted By: Olddawgsrule
Date Posted: 08 Oct 2019 at 1:50pm
Originally posted by Pod People

I understand what Offgrid is saying. We have a 4x8 utility trailer that had a failure where the tongue met the body. It was a single 3x3 beam and not an A frame, so it had only a single point of connection.  Welding a reinforcement beam under the original beam and adding triangle gussets took care of the issue.
with the RPods A frame, at least there are 2 connection points.
Vann

I'm certain Offgrid can explain better, yet what we have, I don't consider a true 'A' frame. The way it is done, I consider it a 'V' frame. Maybe even with the way it's done (and the welds being very good) it should be better than a true straight tongue. Yet I wonder..

Speaking for myself, and what I hope to see done to my trailer (in for warranty frame repair),I figure a 2x2x? will be added under the tongue 'A' frame to stiffen it. Under meaning it would travel past the existing frame cross member and be attached (welded) to the side frame member. That would make it a true 'A' tongue frame.

Here's where I go to Offgrid and ask of what percentage of strength is a weld compared to a through section of frame? My assumption, if the welds are good, 80-90% of original. 



-------------
https://www.youtube.com/channel/UCJduGeZNFgtptH67leItRFQ - Byways no Highways
2017 Tacoma
http://tnttt.com/viewtopic.php?f=55&t=72408 - Truck Camper Build
2004 F150 My Overlander


Posted By: Olddawgsrule
Date Posted: 08 Oct 2019 at 2:32pm
Originally posted by GlueGuy

Originally posted by Jeepinator

Given all the smart people on this thread, I’d like to add another element. What is the underlying risk of exceeding tongue weight and will air bags reduce it?  I’ve not determined my exact tongue weight yet but I suspect I exceed the 350# even with the WDH. 

I am aware that sway and receiver/coupler damage are potential risk factors but I assume there are others. 

The TV and trailer are level when the WDH is engaged.
The WDH does not reduce the tongue weight, it distributes the weight. Effectively it will reduce the amount of the tongue weight applied to the rear axle of the TV, and distributes it to the front axle of the TV and back to the trailer axle. The amount that goes to each axle depends on the torque plus the length of the moment arms.

Also, air bags will not reduce the tongue weight. Air bags will increase the weight that your rear suspension can handle, but will not increase the weight the axle/bearings can handle or the weight the frame of the vehicle will handle.

Here's where I now sit dis-mystifying the magic. And only 'my understanding' of the magic!

Offgrid explained the torque I see as actually being moments of the action introduced by the WDH. I get what he's saying now mostly from watching the video I offered. The magic is being explained.

The down force on the ball from the trailer is not removed. The force (moment/torque) is being displaced by the WDH through it's action. Thus sending X forward and X backwards. Then again that amount being determined by the axle length of the TV (I think I've learned). That again becomes a question of why if the weight of the ball is not removed, then where do we get the addition weight on both the TT & TV? My assumption is because of the action of the WDH. My concern is what is happening on our tongue frame for all this to happen. It's only 2x4x.10 steel and is it capable to compensate? 

That to me is a lot going on on our frame.

I do see by the program Offgrid offered, I need to go back to the scales for some accurate readings for it to work correctly. Which I will do.

Does a WDH work? No doubt it does. More to learn and understand.




-------------
https://www.youtube.com/channel/UCJduGeZNFgtptH67leItRFQ - Byways no Highways
2017 Tacoma
http://tnttt.com/viewtopic.php?f=55&t=72408 - Truck Camper Build
2004 F150 My Overlander


Posted By: offgrid
Date Posted: 08 Oct 2019 at 6:08pm
Originally posted by Olddawgsrule


I'm certain Offgrid can explain better, yet what we have, I don't consider a true 'A' frame. The way it is done, I consider it a 'V' frame. Maybe even with the way it's done (and the welds being very good) it should be better than a true straight tongue. Yet I wonder..

Speaking for myself, and what I hope to see done to my trailer (in for warranty frame repair),I figure a 2x2x? will be added under the tongue 'A' frame to stiffen it. Under meaning it would travel past the existing frame cross member and be attached (welded) to the side frame member. That would make it a true 'A' tongue frame.

Here's where I go to Offgrid and ask of what percentage of strength is a weld compared to a through section of frame? My assumption, if the welds are good, 80-90% of original. 


I can't explain the detailed design of the rpod tongue attachment, I really haven't gone under there and looked at it. What I am saying is simpler:  if you just assume that the trailer frame was made up of two continuous 2x4 beams running from the hitch to the rear of the trailer, and supported by the hitch and the rear axle, what you would have is a simply supported single ended cantilever. If you then loaded those beams uniformly from end to end (not true for an rPod but a reasonable starting point) you would have the standard structural case of a simply supported uniformly loaded single ended cantilever. For that case you can look up the moments and deflections, no need to do some kind of complex analysis. 

That's this case:

https://www.engineersedge.com/beam_bending/beam_bending40.htm - https://www.engineersedge.com/beam_bending/beam_bending40.htm

If you look at the moment diagram, there are two points where the moments reach maximum (which is where the frame will bend if the stresses there exceed the yield strength of the steel). One point is partway between the hitch and the axle, trying to bend the frame down, and the other is at the axle itself, trying to bend the frame up. That's why I'm saying that there is a high bending load location near the front of the trailer, but probably under the box a little bit. Not sure without doing the calcs how the two bending moments compare and exactly where and I'm travelling (without my pod unfortunately) so I can't take the measurements right now. 

Re the strength of a weld, a good welder can make a weldment just as strong as the steel he or she is welding (emphasis on good welder using the proper technique for that weld). If we're talking about adding a doubler tube under the existing tube that is a pretty benign thing to weld because the mating surfaces of the two parts will be at or near the neutral axis of the weldment. The neutral axis is the cross section where there will be no stress (in other words, the location where the parts transition from being in compression to tension when placed under load). 


-------------
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold


Posted By: offgrid
Date Posted: 08 Oct 2019 at 6:54pm
Originally posted by Olddawgsrule


Here's where I now sit dis-mystifying the magic. And only 'my understanding' of the magic!

Offgrid explained the torque I see as actually being moments of the action introduced by the WDH. I get what he's saying now mostly from watching the video I offered. The magic is being explained.

The down force on the ball from the trailer is not removed. The force (moment/torque) is being displaced by the WDH through it's action. Thus sending X forward and X backwards. Then again that amount being determined by the axle length of the TV (I think I've learned). That again becomes a question of why if the weight of the ball is not removed, then where do we get the addition weight on both the TT & TV? 


The weight on the hitch itself is not removed from the hitch but it is removed from the TV rear axle. Think of it this way:  in a statics problem (where things aren't actually moving around) all the forces have to balance to zero and all the moments (separately) have to as well. If the forces don't balance then things would rise up or sink down and if the moments don't balance things would rotate. 

The weight of an object is of course a force pressing downward and is countered by an equal and opposite upward force from the ground.   So, since tensioning the wdh applies moments which are balanced by increasing forces pressing up from the ground at the front axle and the trailer axle, then there has to be an equal reduction in the force pressing up from the ground somewhere else, because the total force pressing up by the ground has to equal the total weight of the rig, which isn't changing. That somewhere else is the TV rear axle.  So the downward force on the hitch itself doesn't change but the downward force on the rear axle does. The front axle load gets higher and the rear axle load gets lower, both of which are good things for your TV.  

There are some downsides though.  There is now a new downward point force on the trailer frame from the tensioning chain/bracket, and there is more load on the already heavily loaded trailer axle. And there is also a moment placed on the TV receiver and frame which wasn't there before. So the tow vehicle and receiver have to be rated for a wdh and the load of the trailer and hitch have to be within those specs. The trailer frame and axle should be rated for the additional load too, which is where axle and frame reinforcement come in. 


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1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold


Posted By: Olddawgsrule
Date Posted: 09 Oct 2019 at 1:42pm
Originally posted by offgrid

 

Re the strength of a weld, a good welder can make a weldment just as strong as the steel he or she is welding (emphasis on good welder using the proper technique for that weld). If we're talking about adding a doubler tube under the existing tube that is a pretty benign thing to weld because the mating surfaces of the two parts will be at or near the neutral axis of the weldment. The neutral axis is the cross section where there will be no stress (in other words, the location where the parts transition from being in compression to tension when placed under load). 

With a bit more research, I find that properly done, the weld can actually be stronger than the parent metal. That does surprise me! I always thought there would be some give in the process. 

Live and learn! Thank you for the input.

Now, for fun of this conversation and how our tongue frame is done. 2x4x.1 steel is everywhere. Being the tongue is welded to the front cross member vs. the tongue being the through member. My mind goes towards the tongue going through would be stronger due to the 'hollow' of the 2x4x.10 cross member. I would think the moments (see, I  am learning.. I think..) happening in the tongue frame are greater than those of the cross member. 

I do think that stacking (not sure of correct term being it would be under) in our existing position would do the deed to enforce the tongue frame. I would also go as far of thinking even a 2x2x.10 steel tube (matching the parent steel) would help in a major way. 
I see far too many folks adding storage boxes, second propane tanks and some many other carrying racks without considering what really happening. Then of course we add a WHD into the mix. 

All said and not attempting to take away from the original threads purpose, I do believe all this is relevant. FR basically is saying their tongue design is meant for (in my case) 385#. 10% of the max weight of the trailer. If over, how do we compensate? I load behind the axle to reduce, yet best I figure, I'm still 15# over. Then comes the action (moments, still tryin' here) of the WDH. 

I'm not saying we own a piece of crap.. We have a pretty decent unit for the dollar and a couple hundred dollars to get it to where it can be is well worth the effort and expense. 

   




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https://www.youtube.com/channel/UCJduGeZNFgtptH67leItRFQ - Byways no Highways
2017 Tacoma
http://tnttt.com/viewtopic.php?f=55&t=72408 - Truck Camper Build
2004 F150 My Overlander


Posted By: offgrid
Date Posted: 09 Oct 2019 at 6:04pm
I'll take a look at the numbers when I get home but I think a 2x2 tube is a good idea. It will add strength without compromising clearance much assuming there is a 4 inch riser at the axle.  I'd probably go a little thicker than 0.1 though, and extend it from forward of the wdh attachment to aft of the front of the trailer box a couple of feet. I do agree that adding a bit of reinforcement to the rpod frame and axle on the heavier units would go a long way to make them more robust. 

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1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold


Posted By: Olddawgsrule
Date Posted: 10 Oct 2019 at 7:49am
Originally posted by offgrid

I'll take a look at the numbers when I get home but I think a 2x2 tube is a good idea. It will add strength without compromising clearance much assuming there is a 4 inch riser at the axle.  I'd probably go a little thicker than 0.1 though, and extend it from forward of the wdh attachment to aft of the front of the trailer box a couple of feet. I do agree that adding a bit of reinforcement to the rpod frame and axle on the heavier units would go a long way to make them more robust. 

If I may ask you, could you run numbers on 1x2x3/16" (7 gauge steel)? That's what my frame repair is and would match up for the tongue support. Yes, it's on the flat..


-------------
https://www.youtube.com/channel/UCJduGeZNFgtptH67leItRFQ - Byways no Highways
2017 Tacoma
http://tnttt.com/viewtopic.php?f=55&t=72408 - Truck Camper Build
2004 F150 My Overlander


Posted By: Jeepinator
Date Posted: 10 Oct 2019 at 3:24pm
Such a great discussion.  I'm living in the "moment".

Based on documented failures, isn't the weld from tongue to frame one of the most significant points for potential failure?  That being the case, I was considering adding reinforcement there as you would not have to give up any clearance on the bottom.  I did examine the weld and it looks pretty crappy.  A shimmed piece of angle properly welded would significantly increase the strength in my unqualified opinion.

I was also going to weld the bolt-on receiver as it tends to flex with the WDH.  I just have to confirm I can still remove my Jeep bumper.


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2018 Jeep Wrangler Willys
2017 179


Posted By: Olddawgsrule
Date Posted: 10 Oct 2019 at 4:04pm
Originally posted by Jeepinator

Such a great discussion.  I'm living in the "moment".

Based on documented failures, isn't the weld from tongue to frame one of the most significant points for potential failure?  That being the case, I was considering adding reinforcement there as you would not have to give up any clearance on the bottom.  I did examine the weld and it looks pretty crappy.  A shimmed piece of angle properly welded would significantly increase the strength in my unqualified opinion.

I was also going to weld the bolt-on receiver as it tends to flex with the WDH.  I just have to confirm I can still remove my Jeep bumper.

As we all are due to Offgrid and his knowledge on this. I do thank him for being so willing.

The question of how is important to all of us. We don't want to just weld more steel/weight without knowing just what the benefit will be. I just went through an examination of the tongue with my dealer repair pro. I was amazed at the tongue weight empty (I do mean no tank or battery there) and it read 375# (or there abouts). Base weight, nothing added and we come very close to what is suggested by FR. Deflection according was only 1/4" as weight was placed upon. 

Throw a propane tank (singular) and my dual batt's, I've added close to 100#'s on that tongue. Given we can back load (behind the axle) to compensate, and we add a WDH. What shall we do to compensate?

That becomes the 'moment' / action we need to deal with. 

My Dealer contact had that 'Deer in the headlights' moment when I asked... Pun intended! 

As my experience continues, and that of others continue to figure out, we shall work this through.

I do wish this thread continues!



-------------
https://www.youtube.com/channel/UCJduGeZNFgtptH67leItRFQ - Byways no Highways
2017 Tacoma
http://tnttt.com/viewtopic.php?f=55&t=72408 - Truck Camper Build
2004 F150 My Overlander


Posted By: offgrid
Date Posted: 11 Oct 2019 at 5:03pm

If I may ask you, could you run numbers on 1x2x3/16" (7 gauge steel)? That's what my frame repair is and would match up for the tongue support. Yes, it's on the flat..
[/QUOTE]

Will do. I finally got home before the road on the island got shut down due to ocean overwash so I should have time to runs some numbers tomorrow.  

My 179's tongue weight is closing in on 550 with full fresh water, dual GC2's, one (not two) full propane tanks, and not much of anything else heavy forward of the trailer axle. Total weight is about 3800 so that's around 14% tongue weight. So yep, as Podwerks says, FR's tongue weight numbers are really not anything like the real world for anyone who does much boon docking with the bigger rpods.  

You have to be careful though too about moving too much weight aft. If, like me, you are returning with all that water moved to the 179's gray water tank that reduces tongue weight percent to about 11. Get much lower than that and the trailer can be sway prone, so there is a sweet spot for me around 14% outbound and 11% inbound. 


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1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold



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