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Old 08-28-2020, 04:47 AM   #21
skids
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Originally Posted by sourdough View Post
Here's what I think I'm thinking...

Truck alone = 6120. Truck + trailer = gross 12,760. Trailer = 6640.

Truck alone = 6120 Truck + trailer = (truck) 6860. Tongue = 740

Tongue 740/6640 = 11.1% tongue weight

If I'm understanding the numbers you look to be in very good shape. The one thing I would not do for any reason is leave off the wdh/sway. If you've never set it up with the trailer loaded you may need to tune it a bit but otherwise looks pretty good. At 11% tongue weight I would definitely get it on the road and check it and make sure it doesn't want to wag due to a light tongue.
I like your sensible language Sourdough. Easy to understand.
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Old 08-28-2020, 05:41 AM   #22
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Speaking to the bounce ... I'd suggest shifting some weight around before spending and money. The 11% is a bit on the light side to me, especially using a WDH. It will only cost you a little fuel and a little time.

When you go on your next outing (loaded as usual) when you traverse that bridge or section of the road that creates the bounce safely stop. Move some weight forward, turn around and drive over the same road at the same speed.
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Old 08-28-2020, 07:16 AM   #23
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The 2 trailer axles you weighed together.
You can yudge the weightdivision between those 2 axles by the difference of deflection of the tire.
Measuring the deflection is of a high " hobby Bob" value, but it gives a good indication.
Same deflection on all 4 tires means each 25%of the 5900lbs .
So you can also adyust it for a staight trailer.
If you go for this you never wil have same deflection.
Often weightdivision is crossed between the axles.
For instance RF 20% ,LF 22%, RR 30% LR28%.
Then rear axle more load, so most likely front of trailer to high. The crossed difference RL you can not take away with changing the WDH.

And deflection is quadratical with the load on tire.
If deflection 2x as much, weight on tire 1.41x as much, so root. Or 2x load gives 4x deflection.
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Old 08-28-2020, 08:02 AM   #24
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The 2 trailer axles you weighed together.
You can yudge the weightdivision between those 2 axles by the difference of deflection of the tire.
Measuring the deflection is of a high " hobby Bob" value, but it gives a good indication.
Same deflection on all 4 tires means each 25%of the 5900lbs .
So you can also adyust it for a staight trailer.
If you go for this you never wil have same deflection.
Often weightdivision is crossed between the axles.
For instance RF 20% ,LF 22%, RR 30% LR28%.
Then rear axle more load, so most likely front of trailer to high. The crossed difference RL you can not take away with changing the WDH.

And deflection is quadratical with the load on tire.
If deflection 2x as much, weight on tire 1.41x as much, so root. Or 2x load gives 4x deflection.
Wow, just wow. So while that's an impressive theory how do you practically take the field measurements? Remove each tire and measure the deflection unloaded first? Then run a laser level across the surface and find a perfectly level place to then make sure the trailer is perfectly level? Then what? Run a laser level across the tire at that tires unloaded height and measure the difference? To what unit of measure? and where's the scale for deflection on that make, size, inflation tire?

I'm tired just thinking about this. Seems to me it would quicker and easier to find a scale that measures individual tire weights as apposed to axle weights if someone thinks there's really an imbalance side to side load that's a factor. But that's just me. JMMV
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Old 08-28-2020, 09:00 AM   #25
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Marshall, Wow is right, while I am sure it is a great theory that made my head spin and I am an engineer (retired). I will however attempt to move some load up front although I am not sure how much is really available since the pass through storage is in the front and there are two 6v batteries and two full 30lb propane tanks on the tongue. One other consideration is there was no water in any of the tanks which is how we attempt to travel. If the fresh water tank (40gal) located approximately mid way between the axle and the front was full or partial it would add some additional weight to the tongue. the downside of course is it adds additional weight to the camper.
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Old 08-28-2020, 09:16 AM   #26
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Marshall, Wow is right, while I am sure it is a great theory that made my head spin and I am an engineer (retired). I will however attempt to move some load up front although I am not sure how much is really available since the pass through storage is in the front and there are two 6v batteries and two full 30lb propane tanks on the tongue. One other consideration is there was no water in any of the tanks which is how we attempt to travel. If the fresh water tank (40gal) located approximately mid way between the axle and the front was full or partial it would add some additional weight to the tongue. the downside of course is it adds additional weight to the camper.
Watch out when partially filling tanks and driving; the hydrodynamic force inertia can bite you in the butt...
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Old 08-28-2020, 09:35 AM   #27
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^^^ What Javi said !!!!!

A 45 gallon water tank, filled to the brim is 375 pounds of "ballast"

A 45 gallon water tank, half filled is around 200 pounds "slamming back and forth against your trailer "centerline"... If the tank is in the front of your trailer, there's not as much "dynamic force" applied 4' behind the hitch pivot point as there is if the tank is at the rear of the trailer, 30' behind the hitch pivot point.

Some tanks are molded with baffles in them. Those baffles are most often only in the bottom of the tank and only 2-3" in height, so having 10 or so gallons in the tank, the baffles are effective. Half full: not so much as the water level "sloshes above the baffles"....

Next time you're in a 10 or 12 foot rowboat, start rocking side to side and you'll see what 200 pounds of water, 30' behind your hitch ball can do to your "perception of sway at the steering wheel.....
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Old 08-28-2020, 09:43 AM   #28
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Marshall, Wow is right, while I am sure it is a great theory that made my head spin and I am an engineer (retired). I will however attempt to move some load up front although I am not sure how much is really available since the pass through storage is in the front and there are two 6v batteries and two full 30lb propane tanks on the tongue. One other consideration is there was no water in any of the tanks which is how we attempt to travel. If the fresh water tank (40gal) located approximately mid way between the axle and the front was full or partial it would add some additional weight to the tongue. the downside of course is it adds additional weight to the camper.
Several years ago DW and I took a nice long trip, headed to Dollywood we ended up "meandering" across 1/2 the country for almost a month. Anyway, I loaded up the trailer, used my SherLine tongue scale and had it set up great.

Unknown to me, the DW loaded a bunch of canned goods, several cases of water, and "extra" cloths in the camper, all in the very back on the floor. We got about 2 hrs down the road when I noticed the wind died down but the trailer was fighting me to stay straight. I pulled into a rest stop and told the DW something was off. She told me she placed "a few extra things" into the camper after I thought it was loaded. Good bless her soul, to her, packing a "few things" looks like the Queen of England taking a cruise in the Mediterranean.

A "redistribution" of weight solved the issue and taught me to never take off again without a "visual" of the inside first.
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Old 08-28-2020, 10:45 AM   #29
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I already wrote, the deflection methode is of a high " hobby Bob" value. But meauring the deflection is not that difficult. Mesure from upper rimmedge to the ground, and from downunder-rimmedge to a little flat piece of material , you place flatt on the treath at the top of tire.

OK, not verry acurate, but enaugh for the purpose.
Even if you are able to read it 99% acurate, there is a difference, the top of tire is probably also a verry small part deflected, and rear and front side , seen fom beside, sidewall is a bit flexed so higher then unloaded( off the ground) . The tire becomes a bit oval when deflected.
What you need is the % deflection of free flexible part of sidewall, and that is roughly section hight minus 1 inch ( part in te rimedge+ treathdepth).
You could calculate it with the sises of tire( again roughly, because for instance a 255/
50R 16 is not exact 255 sectionwidth, but can be 258 , they round it down for standardisation reasons.
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Old 08-28-2020, 01:09 PM   #30
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Wow, just wow. So while that's an impressive theory how do you practically take the field measurements? Remove each tire and measure the deflection unloaded first? Then run a laser level across the surface and find a perfectly level place to then make sure the trailer is perfectly level? Then what? Run a laser level across the tire at that tires unloaded height and measure the difference? To what unit of measure? and where's the scale for deflection on that make, size, inflation tire?

I'm tired just thinking about this. Seems to me it would quicker and easier to find a scale that measures individual tire weights as apposed to axle weights if someone thinks there's really an imbalance side to side load that's a factor. But that's just me. JMMV
Wow is right!
Been looking for the translator app on my phone but not sure what language it was???
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Old 08-28-2020, 02:06 PM   #31
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That I write a little strange english, is because its not my first language, I live and grew up in the Netherlands. This together with writing errors, because doing it on mobile phone, can give, that you think to need a translator app.
Typing on mobile, asks much of fine motorics, of this 60 year old man.
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Old 08-28-2020, 04:35 PM   #32
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That I write a little strange english, is because its not my first language, I live and grew up in the Netherlands. This together with writing errors, because doing it on mobile phone, can give, that you think to need a translator app.
Typing on mobile, asks much of fine motorics, of this 60 year old man.
It sounds like it "might" be founded on physics theories. But like they tell you in Engineering college, "Mother Nature is a bitch", meaning that the constants actually vary. I wouldn't trust the deflection of tires as spring constants...heck, a lot of them can't even hold air in them without blowing up! I live in a county in Colorado where you can't even find a flat enough spot to check your engine oil.
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Old 08-28-2020, 05:01 PM   #33
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Originally Posted by flybouy View Post
Unknown to me, the DW loaded a bunch of canned goods, several cases of water, and "extra" cloths in the camper, all in the very back on the floor.
Good bless her soul, to her, packing a "few things" looks like the Queen of England taking a cruise in the Mediterranean.
I do believe Luci and Desi got an hour and a half movie out of this very premise!
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Old 08-28-2020, 05:57 PM   #34
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jedatis, kudos to you for your mastery of the English language. Having been in Amsterdam/Holland many times, the very best I can do in Dutch is "We nemen twee biertjes" (We will have two beers). And I shouldn't even mention how well you've tamed our language, not even living here, as opposed to those.....naw, Jim, better not go there.
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Old 08-28-2020, 07:14 PM   #35
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jedatis, kudos to you for your mastery of the English language. Having been in Amsterdam/Holland many times, the very best I can do in Dutch is "We nemen twee biertjes" (We will have two beers). And I shouldn't even mention how well you've tamed our language, not even living here, as opposed to those.....naw, Jim, better not go there.


I have to say, from my "older" point of view, that the mastery of another language is something to be acknowledged. I've lived all my life in the SW and Mexican is the "other" language. I know a lot of it because I've lived it all my life. I expect 100% enunciation and understanding of the English language from any "citizen". Those from another country will, and do, have problems with our "language". At that point in mind I think we just have to muddle through language anomalies as we go. I can communicate with anyone in English; I wish I had the ability/knowledge to communicate to everyone with any other dialect... I do not. Anyone, as an American citizen HAS to be able to express their thoughts "in our world" in understandable English; those from other countries, with different languages.....we have to try to figure out.
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Old 08-29-2020, 01:43 PM   #36
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My hat is off to those who have mastered multiple languages and in particular those, like jadatis, who have mastered English as a second language. Having lived and worked across multiple countries in Europe I has always amazed at the number of people who spoke two or more languages fluently. As an American I felt extremely luckily that English is the universal language of business.
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