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Old 10-13-2021, 01:09 AM   #1
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Part 4- Airstream Fairy Tale: 27FB Separation

Part 3: 27FB Separation Lessons Learned and Discovery

NRYM solved the Riddle of the Rivets! A First Hand Eye Witness to the Airstream Separation Fairy Tale with the Post about his Indents.

Airstream Fairy Tales:

First AFT for the Year 2021: "Hitch Ball lock washer and nut fell off."

Airstream Fairy Tale This reminds me of the Thread about someone's Ball on their Hitch had the lock washer and nut 'detach' and the Ball Departed the Hitch Assembly... thread earlier this Year.

I asked for ONE EXAMPLE. Just One. Well, maybe TWO.

ZZZZZ Not Two examples. Not even ONE. I asked HOW would it be possible, anyways?

The Thread Ended and we all went back to watch Television and get our 'Fairy Tails' every day in the 'Real World'.

******

Second AFT for the Year 2021: "Front Bed Separation of Late Model Airstreams"

NRYM solved the Front End Front Bed Separation in Part 3. The Indents. Part 3, Post #16.

After asking for anyone to provide Front End Separation Evidence... and getting plenty of Indents... these being a blemish, for sure... but NOT Separation like those older Airstreams being restored.

These Indents seem to begin and end at the lower left and right corners of the storage compartment.

My Cost to add some strength to this area was less than $40.00.

My Cost of Labor were hours of distraction and discovery of... well, nothing having to do with Separation of anything but my... $40.00.

******

A 'whole lot' of Airstream Owners actually went out to look at their trailer... very closely. So close, they noticed other things to do this Winter with their Airstream. I could not find anything else other than the Indents.

I have had two years to work out tweaking our 27 footer. And done very well with Lath Screw, piano hinges and other improved hardware.

Are there any other Examples, true or half truths, of Airstream Fairy Tales?

Mine is complete. No Grinches. Lots of smoke, but no fire. If you have more Fairy Tales to add... do it now.

I would recommend that EVERYONE with a Front Bed, remove the forward plywood section to actually LOOK at your Own Front End sloppy finish, aluminum debris and some actual factory dirt. You may discover the Airstream Factory used some long SCREWS and not Rivets behind the Silver Strap surrounding the bottom of the trailer.

An area that is big and wide. There is some distortion on the inner aluminum skin cutout material not secured under the rubber gasket.

Two nuts may need to be tightened and secured. You will see and find them. Maybe add some structure to support side to side. Use Lath Screws. Nobody will know, see or tell anyone. It is behind and under your bed and below the hinge of the opening.

This Airstream Fairy Tale ends with a happy ending. What it is... is your to decide. For me... I have been there, seen it and screwed it with 1/2 inch Lath Screws. If that is not a Happy Ending... you need to write your own Airstream Fair Tale. Mine is done.

Sleep Well and be good. 'POP Rivet' is a Gremlin inside our trailer. He will get you eventually.
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Old 10-13-2021, 02:18 AM   #2
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Particle board Fairytale.

Hi, I have heard complaints about Airstreams use of particle board in cabinets. I have been into virtually every part of my Airstream and found nothing but plywood. I have had my bed apart. I changed my bathroom faucet. I remodeled my living room and made my own credenza and love seat. I have worked on closets. I have been into my kitchen cabinets. I have found virtually everything was made from plywood or solid Oak in some places, but no particle board or MFD.

I made my case and asked for picture proof that their Airstream cabinets were made from particle board or MDF. Most people never responded and a few looked deeper and found what they thought was particle board was actually [as I said] plywood.
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Old 10-13-2021, 08:09 AM   #3
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Riveted Aluminum Shell Airstream only?... No Screws?

I discovered that my Airstream not only had Rivets on the lower band... but oversized screws. And at random.

I have the evidence. You see Buck Rivets alongside the screws. I suspect that when this band was being secured... some areas needed to be reinforced. Too late for Buck Rivets... but not too late to Screw. The screws went through the skin and into this angle support below the front door hinge.

This is Airstream Fairy Tale #3. All Rivet Aluminum Exterior Skin on All Airstreams? Not mine. Maybe an exception. Makes me feel special...

My preferred method is applying Lath Screws. Now from 1/2 inch to 1 1/4 inch in lengths. The 1/2 inch and 3/4 inch are 90% of what I have needed to apply. My 'tool' sitting on my work bench. Those Rivets to attach the added support aluminum metal will resist the temptation to fail.
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Old 10-13-2021, 08:17 AM   #4
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Ray, When I replaced the decorative vinyl chrome strip on the lower belt line (because it had faded to gray) last year I noticed the extruded aluminum piece of the banding is held on by sheet metal screws every foot or so. Some of the screw heads were rusted so obviously not stainless. Those may be what you're seeing in your photographs from the inside.

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Old 10-13-2021, 08:34 AM   #5
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No shortage of Gorilla Tape or Lath Screws!

Kurt... that might explain a bulge I see below the front storage hinge. A bulge. Also I noticed that behind the Rock Guards... there are several RUSTY ends of possible screws.

I applied Black Gorilla Tape where dust was coming in from the aluminum and floor. Also on the floor, over the linoleum. Why? Well... had to do something with this roll of Gorilla Tape and have lots of time on my hands. Drilled holes in the aluminum for placing the Lath Screws so they were sharp and would hold.

The threaded ends are nice and clean and sharp that Airstream used. This means I am not getting any Water or Moisture into the interior. Yeahhhh.

After my probing this front area of my 27 foot post 2000 Airstream, I am confident that some additional support in between the front and inside skins... are secure and will not flex.

Even though metal expands and contracts daily... it is not enough to put much stress on the large number of heavier rivets on the exterior. The interior rivets... Mr. POP Rivet at work.

I have my battery powered screw driver, my Lath Screws and fix it before it becomes a problem. I have an electric hand drill for drilling starter holes and apply the Lath Screw until it is flush. This is not a Fairy Tale. It is a Lath Tail... of sorts.
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Old 10-13-2021, 08:41 AM   #6
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I have always felt the "front end Separation" is a misnomer. Rear separation is a situation where there is a pulling force between the frame and body, resulting in a "separation" of the two.

The front situation (whether you have a front trunk or not) is a compression situation, resulting in a buckling of the front wall assembly.

I believe that no amount of the current c-channel fixes does anything to cure the forces at play. A "front hold down plate" will certainly cure the lower rail area from stresses, but it just transfers the forces up north, in the wall window frame, etc. Is that good enough? IDK.

My analysis finds that the real issue is in the frame design and construction itself.

Most "box" trailers have the front frame cross member, at the front wall extending to a square corner and joining the frame rail at its front tip. This transfers much of the flex and torque created at the ball by TW and WD application to the frame at 1) at the front cross member, and thus directly to the frame rail, at the front wall 2) on back, where the angled tongue rails are welded to the frame rails.

Our ASes have a short front cross member only between the a-frame at the front wall. This allows for much more of the torque to be applied some 30" aft of the front wall.

If you notice, everyone who has posted has damage to the wall right where the a-frame rails are located, front trunk or not. I do.

See the attached line drawing of an older 30' classic. I believe you will find this common construction across the lines and model years. There does seem to be a (flat?) "reinforcement" aft of the front wall, but I don't think that is sufficient. I have never had my belly skin off in that area to be sure what the line drawing indicates.

I believe that if there were a front frame crossmember between the frame rail tips and the a-frame, a substantial portion of the torque load would be transferred to the rails, much further forward, thus reducing the flex and load at the point where the a-frame meets the front wall.

Frame_line_drawing.pdf

Ray, I am glad for you that you found "solace" in your journey, but I don't think it is all joy.

All we can do is try and keep TW at an acceptable level, use the least amount of WD to get a proper job done, and use the least rated, most flexible WD spring bars possible.....AND/OR add a boxed section of cross member between the a-frame and frame rail tips....heck, maybe more than one.
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Old 10-13-2021, 09:03 AM   #7
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Rich, that was an amazing drawing. I took a look at it paying particular attention to the front as you suggested.

All I can say is wow. I too wonder if that cross member at the base of the A frame is an actual frame component or just a flooring cross. I see what I think is about 38 (assuming inches based on the print) under where the front wall sits on the A frame, something that looks rather puny.

I'm far from a structural engineer, but I have made some common sense structural modification on homes I was renovating with great success. That still does not make me an engineer, but I'd like to think I do have a fair level of common sense.

If what I am reading from this print is correct, adding your narrative, I'd be inclined to agree that putting "L" brackets, though it will solve the immediate problem, prob is not the best long term fix.

If someone were to open the bellypan and confirm what you say and what I think I am seeing, then the simple (relatively speaking) fix would be to weld some steel crosses at the locations you suggest to add additional support....and I know, just want you wanted to do after spending $100k on a trailer.

This print however does clearly say OBSOLETE, and replaced by...I wonder if the drawing that replaced this one shows any modifications to the area in question. My guess is no given we are seeing 2020 and 21s showing this issue.
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Old 10-13-2021, 10:48 AM   #8
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A frame flex

While looking at the drawing and pondering all that has been written on WD hitches I can't help but wonder how much flex may be applied to those A frame rails with 2000 lbs torque being applied to the center of the span by the weight bars. On single axle semi truck tractors it is common to have 10,000 lbs on steering axle and 20,000 on drive axle. Pickup trucks IMHO are designed to be lighter on the front axle when carrying a load than when running empty. With a proper sized truck with competent sized suspension for the job whether spring or air or combination of both WD hitches should be unnecessary. A little sway control would be nice for those times when not paying attention to driving. Driving a combination vehicle of any size requires constant attention for safety reasons.
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Old 10-13-2021, 12:08 PM   #9
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Tow Vehicle & Hitch Choice & Tires & Dexter Axles= UNKNOWN

Posts #6, #7 & #8 are adding fact to opinion and fiction. Excellent.

I towed our 25 foot with the F350 4x4 Diesel and Equalizer Hitch, 1000# bars. Could have towed on the ball... but the Sway Control was a bit of insurance. Never a popped exterior rivet.

Had interior rivets with a Tundra 4x4 towing the 23 and 25 foot and do not recall any with the F350, later. The weak 'links' were the curved interior pop rivets and less than 8 or so. The Tundra was FLAT Sprung leaf springs. With Weight Distribution the Tundra rode like an Airstream. Reduced the WD and liked the ride, but headlights at night were hunting a bit off the pavement and into oncoming traffic.

I have towed the 27 foot with the F350 on the Ball. At highway speeds. Also when on NFS and BLM irregular unpaved roads at speeds under 35mph. Better roads at 45mph. Maybe 8 interior rivets on interior curve. Hinge screws and hinges like the 25 foot originally, but then reinforced ALL original hinges with better screws, hardware or Zip Strips to avoid vibrations causing hinges to come apart. Today... a rare occurrence. But carry extra zip ties, Lath Screws, and extra hardware for small items.

The Lath screws replacing Interior Pop Rivets have held. They are hard to find, but I need to get an accurate count. Use the 1/2 inch lengths. Sometimes the interior skin has an air gap from the skin to the frame and I go to a 3/4 Lath screw.

As of this moment. The 27 foot is 100%, other than the Front End... and that will be tested.

I DO NOT NEED WEIGHT DISTRIBUTION towing the 27 foot with the F350. The 1000# bars are not under any stress level. Can be hand lifted and set on the L Bar mounted to the Frame. Just the security of SWAY, which on the Ball was minimal... at worst. But an Insurance Policy if sway control is needed.

If my Sway is too minimal... I may have to RAISE the L Bar one inch, which will put Weight Distribution Friction on the L Bracket if I 'feel' uneasy with less WD.

I travel with different loads, mostly in the F350 bed. Water Tank full. Grey and Black with several gallons of fresh water to slosh, but used very little. A plastic wash pan in the sink takes care of Grey Water when I toss it onto the prairie.

Frame Flex? Stiff towing? Towing with trailer just down about an inch in front. Any interior loosening of bolts and small pop rivets are probably more the Dexter Axles at work... and not the Hitch or F350.

Everyone has an opinion from Experience. Mine... the Axles are tough on an Airstream. Start there? Then work up to the HITCH and then Tow Vehicle?

The Fairy Tale of the Tow Vehicle and Hitch could be just that. Could it be the suspension of the Airstream? Do Other Brands with LEAF SPRING Support... shake their fiber glass and interior apart? Let us know.

Does anyone have an opinion about Dexter Axles and how the Airstream Shell, Interior and Frame handle? Or is this... Taboo? Sure do not want to whack the Bee Hive or Hornets Nest, but TIRES cannot always be the Bad Guy.
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Old 10-13-2021, 08:44 PM   #10
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Having a hard time here.

Iíve been following this separation discussion since it first posted. Iíve been really confused on what people were trying to logically explain. The physics of stresses from the tow system running up through the walls MAKES NO SENSE unless weíre all driving around some sort of suspension bridges now. The WD runs overall weight through the bars from the TV to the trailer and back. To say that the WD bars run the stresses up the front on the trailer is physically not possible. The trailer body compresses itís weight downward onto the trailer frame. The trailer frame is the bridge being supported by the axle(s) as a pier. If youíre having shell separation issues, donít look at the WD, look at the shell support system.
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Old 10-14-2021, 06:40 AM   #11
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Iíve been following this separation discussion since it first posted. Iíve been really confused on what people were trying to logically explain. The physics of stresses from the tow system running up through the walls MAKES NO SENSE unless weíre all driving around some sort of suspension bridges now. The WD runs overall weight through the bars from the TV to the trailer and back. To say that the WD bars run the stresses up the front on the trailer is physically not possible. The trailer body compresses itís weight downward onto the trailer frame. The trailer frame is the bridge being supported by the axle(s) as a pier. If youíre having shell separation issues, donít look at the WD, look at the shell support system.
As Al Borland would say, "I don't think so, Tim."
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Old 10-14-2021, 07:52 AM   #12
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Originally Posted by DAVSCH View Post
I’ve been following this separation discussion since it first posted. I’ve been really confused on what people were trying to logically explain. The physics of stresses from the tow system running up through the walls MAKES NO SENSE unless we’re all driving around some sort of suspension bridges now. The WD runs overall weight through the bars from the TV to the trailer and back. To say that the WD bars run the stresses up the front on the trailer is physically not possible. The trailer body compresses it’s weight downward onto the trailer frame. The trailer frame is the bridge being supported by the axle(s) as a pier. If you’re having shell separation issues, don’t look at the WD, look at the shell support system.
I'll take a stab at this one and please if I've missed the mark, someone please show me the light.

In normal circumstances you might be right, but you are assuming that the frame under where the shell meets the frame has the correct support. It may or it may not, no one knows for sure because no one wants to pull their belly pan to see.

On an unenclosed SOB, you can clearly see the steel cross member where the body meets the frame in the "A" frame. Folks seem to feel that that cross member on an Airstream is further back. I can't say for sure if it is or it isn't.

If it is, you are right, if it is not, then that is where the we diverge.

From what I've read, Airsteam did not secure (very well) the front shell to the floor and skin deformation began, particularly with units that had a front storage access door.

In my *opinion* the body flex could have happen with or without WD, but with WD, there are more stresses placed on the "A" frame and seemed to accelerate the issue. If the shell wasn't secured well, those stresses could cause the skin deformations folks are seeing.

What Airstream did in response was to place "L" brackets and bolts through the floor. This stops the body from pulling apart from the floor. However, it's been suggested that the steel cross member similar to SOBs where it's located exactly where the body meets the frame is not the same on an Airstream frame. If this is true, then we've solved the immediate issue, but not addressed the root cause. What this means is that if what folks are suggesting is true, then we have a very well secured body to the floor and we now have a possible situation where the floor and shell by marriage is now having movement (however slight) because there wasn't anything to bite into beyond the floor and last I checked the floor alone is not a structural support as being described here.

The earlier attached architectural drawing seems to support this theory. The only way to know for sure would be to drop the bellypan up front and see if in fact there is steel running the width of the "A" frame where the body meets the frame. If it's there like it is on SOBs, this is a non-issue and Airstream's fix is solid as they most likely bolted through the floor and the steel frame cross member. If not, flex will continue and most likely rivets pop long term with stiff connections to the TV, thus the stresses being shared by the entire structure up front, including the wall, and putting additional stresses onto the "A" frame to distribute weight, might still accelerate with WD compared to dead weight on the ball, though in my opinion, if no steel cross member under where the body meets the frame up front, nor bolted through it, harsh roads, too stiff suspension might also still provide flex, but to a lesser degree.

I'll attached the fix diagram someone shared here. It also does not indicated a bolt being put through a frame cross member, so it's hard to tell even by this if the frame rigidity is there.

That's my take FWIW.
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Old 10-14-2021, 08:00 AM   #13
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As Al Borland would say, "I don't think so, Tim."
Got a chuckle out of me with this one, Rich.
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Old 10-14-2021, 08:04 AM   #14
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I'll take a stab at this one and please if I've missed the mark, someone please show me the light.

In normal circumstances you might be right, but you are assuming that the frame under where the shell meets the frame has the correct support. It may or it may not, no one knows for sure because no one wants to pull their belly pan to see.

On an unenclosed SOB, you can clearly see the steel cross member where the body meets the frame in the "A" frame. Folks seem to feel that that cross member on an Airstream is further back. I can't say for sure if it is or it isn't.

If it is, you are right, if it is not, then that is where the we diverge.

From what I've read, Airsteam did not secure (very well) the front shell to the floor and skin deformation began, particularly with units that had a front storage access door.

In my *opinion* the body flex could have happen with or without WD, but with WD, there are more stresses placed on the "A" frame and seemed to accelerate the issue. If the shell wasn't secured well, those stresses could cause the skin deformations folks are seeing.

What Airstream did in response was to place "L" brackets and bolts through the floor. This stops the body from pulling apart from the floor. However, it's been suggested that the steel cross member similar to SOBs where it's located exactly where the body meets the frame is not the same on an Airstream frame. If this is true, then we've solved the immediate issue, but not addressed the root cause. What this means is that if what folks are suggesting is true, then we have a very well secured body to the floor and we now have a possible situation where the floor and shell by marriage is now having movement (however slight) because there wasn't anything to bite into beyond the floor and last I checked the floor alone is not a structural support as being described here.

The earlier attached architectural drawing seems to support this theory. The only way to know for sure would be to drop the bellypan up front and see if in fact there is steel running the width of the "A" frame where the body meets the frame. If it's there like it is on SOBs, this is a non-issue and Airstream's fix is solid as they most likely bolted through the floor and the steel frame cross member. If not, flex will continue and most likely rivets pop long term with stiff connections to the TV, thus the stresses being shared by the entire structure up front, including the wall, and putting additional stresses onto the "A" frame to distribute weight, might still accelerate with WD compared to dead weight on the ball, though in my opinion, if no steel cross member under where the body meets the frame up front, nor bolted through it, harsh roads, too stiff suspension might also still provide flex, but to a lesser degree.

I'll attached the fix diagram someone shared here. It also does not indicated a bolt being put through a frame cross member, so it's hard to tell even by this if the frame rigidity is there.

That's my take FWIW.
IMO, this is correct. Where, I think Davisch is going is based on a belief that an AS is like a "box-on-rigid-frame"trailer, like an SOB. It is not. It is a semi-monocoque unitized assembly with a lighter, more flexible frame as its bottom. As such, the entire shell is a structural member of the entire assembly. No it is not a suspension bridge....more like a truss bridge with a pier at one end and in the center(ish) and almost half of it cantilevered...hanging in the air.
I'm not going to get into the weeds discussing a semester's worth of math and physics.
One needs to do their own research on semi-monocoque and load/stress in this application. Loads are transmitted through the front wall...it is in compression just sitting on the ball. Add some 800 to 1000 pounds of WD bar end force, let alone the dynamics of going down the road (with vertical articulation) and the stresses are pretty notable.
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Old 10-14-2021, 09:21 AM   #15
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IMO, this is correct. Where, I think Davisch is going is based on a belief that an AS is like a "box-on-rigid-frame"trailer, like an SOB. It is not. It is a semi-monocoque unitized assembly with a lighter, more flexible frame as its bottom. As such, the entire shell is a structural member of the entire assembly. No it is not a suspension bridge....more like a truss bridge with a pier at one end and in the center(ish) and almost half of it cantilevered...hanging in the air.
I'm not going to get into the weeds discussing a semester's worth of math and physics.
One needs to do their own research on semi-monocoque and load/stress in this application. Loads are transmitted through the front wall...it is in compression just sitting on the ball. Add some 800 to 1000 pounds of WD bar end force, let alone the dynamics of going down the road (with vertical articulation) and the stresses are pretty notable.

Pardon me, I should say.

"No it is not a suspension bridge....more like a truss bridge with a pier BEYOND one end and in the center(ish) and almost half of it cantilevered...hanging in the air."

The "BEYOND" component is what aggravates the situation, along with additional significant load of WD between the "pier" and the first "truss" members.
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Old 10-14-2021, 09:33 AM   #16
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Slow down, run less air in the trailer tires…6-800# bars…no problems for 70,000 miles..my 04 30’ Classic did separate at the front…I got rid of that heavy fancy hitch everyone brags about..
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Old 10-14-2021, 09:39 AM   #17
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Slow down, run less air in the trailer tires…6-800# bars…no problems for 70,000 miles..my 04 30’ Classic did separate at the front…I got rid of that heavy fancy hitch everyone brags about..
I don't think the "heavy fancy hitch" has anything to do with it, other than the bar rating and its flexibility. The forces at play here are from the coupler and aft.

I kind of wish I had bought 800# bars with my propride, rather than 1k bars. I used 800# bars on my old Reese dual cam. They worked fine, but I felt I was at their limit.
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Old 10-14-2021, 09:45 AM   #18
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Quote:
Originally Posted by tjdonahoe View Post
Slow down, run less air in the trailer tires…6-800# bars…no problems for 70,000 miles..my 04 30’ Classic did separate at the front…I got rid of that heavy fancy hitch everyone brags about..
Totally on board with the 6-800lb bars, but with a 30 footer tipping the scales around 10,000lbs with E rated tires and factory sized rims (assuming 15"), not sure I would venture too far south of say 75lbs and honestly, less PSI isn't gonna do much for the front end separation.

https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf
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Old 10-14-2021, 03:11 PM   #19
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Here is an exercise to illustrate what I have been talking about relative to A-frame flex.
Setup: I took these pics and measurements while the AS was resting on its tongue jack and while resting on jack stands placed at the point where the A-frame is welded to the side rails back at the first frame cross member (at rear of the spare tire compartment). I placed a block of wood to elevate the compartment door edge to the level of most wall bulge. All this is sans TV and WD. I'll have to wait till I hitch up next to get measurements with WD applied.
I couldn't get the camera at a point not to be angled for a straight shot at the rule, so my stated distances will be different than what you discern in the pics, but will be consistent.

First shot is with the AS on its tongue jack. the measurement is 7/32"

Attachment 406257

This shot is with the tongue jack retracted and the AS sitting on the stands, without moving the rule and illustrating the release of compression of front wall and diminished bulge.

Attachment 406259

The measurement in relaxed position as described is 11/32".

Attachment 406260

Next illustration is a measurement from the top of the propane cover edge to the trailer front wall.

First one is with the AS on its tongue jack. Measurement is 9 3/16"

Click image for larger version

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Last one is a shot with the AS on jack stands. Measurement is 9 7/16"

Click image for larger version

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It is clear there is a lot of A-frame flex. Judging by anecdotal visual experience, when I do measure with WD applied, we will see significantly more bulging as expressed with an additional set of measurements.

Edit: Got an error message on the first 3 pics. Will contact administrator. Stay tuned.
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Old 10-14-2021, 03:16 PM   #20
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um, how do I contact administrator?
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