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Expansion, Contraction, Sealing and Moisture Integrity of corner tr
Yahoo Message Number: 48422
Hello fellow LD owners, I've waited for current postings on this subject to subside before commenting.  That's happened, so this is my second of two postings on this subject, updating comments based on my training and experience:

I urge you do a search of the message database from this bulletin board for postings with the phrase "End Caps" in message texts and then for messages with the word "sealant" in message texts.  (In messages with me, the mothership has identified as "End Caps" those corner trim pieces they apply on the exterior joints of vertical walls and roof, rear and overhead cab panels.) In that database search, you should find messages with specific definitions of end cap conditions, what the mothership has done in the way of product improvements in production, and what has worked in the way of repair of those problems (and what has not worked).  Print out those messages that apply to your LD.

Then, write down the End Cap configuration of your specific LD regarding End Cap material and attachment, when any repairs you had done were made, what sealant was used in those repairs and also, record when you inspected the End Caps and what you found and/or did to repair any problems.

Then, add the above data to your maintenance record loose-leaf (We all have one, right?) and keep it up to date as long as you have your LD.
 To update my comments on our LD End Caps, I'll respond to a specific posting: On 21 December 2004, Robert Blackard (blackardrobertatyahoo.com) posted message 48131 about his 2001 26ft RK end cap situation.
 (Here is an integration of some of Robert's words in quotation marks followed by my response): "Hi Folks Have a little problem on my 01 26ft RK. The radius corner trim at the back of the rig is in 2 parts with a seam about eye level, a caulked seam.  If it is cold it separates and when the sun shines on it expands and closes up.  (This is) definitely a place for water to get in. Not good on a wood frame. Is this trim aluminum?"

Hello Robert, The radius corner trim End Caps / Cap Strips on Lazy Daze of this vintage are made of ABS material.  Many of us would call it plastic.
The ABS End Caps are attached with VHB bonding tape and with screws that are selectively located in accord with mothership experience and design criteria.  That's why you see lots of screws along the top End Caps and very few on the rear and front side vertical End Caps.

Bonding of the VHB tape was improved in production of 2003 & later LDs.  This was done by applying an bond activation compound, which increased the bond strength, just before the bond was made.
The `bonding adhesive activated' VHB tape used on the 2003 & later LDs appears to be thinner than used on earlier LD, (such as used on our 2001 LD).  Perhaps as a result of these two factors, the use of sealant applied along the edges of all the End Caps was concurrently discontinued.
 I also should mention that on all LD using the VHB bonding tape, the VHB tape and its bond joint are designed to allow for some movement without failure of the adhesive bond.  This means the bonding attachment of the End Caps is designed to not fail as the temperature changes and the coach moves.

The following item is repetitive to what has been stated in earlier postings, but is repeated here to provide an more complete covering of the subject in one posting:  On 2003 and subsequent LD production, End Caps joints at about eye level on the two vertical rear End Caps were changed from a joggled overlap joint to an expansion gap joint with the gap covered by an external cap strip attached with a screw at each end of the cap strip.  That allows the expansion gap-joint opening to expand or contract while remaining covered by the cap strip.

Measurements I have made of our 2001 LD, which has the joggled overlap joint, show that the expansion / contraction of the gap is somewhat more than a tenth of an inch between summer and winter temperatures.
 I hope it is reassuring that on 2002 and a few years earlier LD using ABS End Caps, their joggled overlap joints are configured such that the upper End Cap section overlaps the lower End Cap section by about
Re: Expansion, Contraction, Sealing and Moisture Integrity of corne
Reply #1 –
Yahoo Message Number: 48426
Quote
Hello fellow LD owners, I've waited for current postings on this subject to subside before commenting.  That's happened, so this is my second of two postings
If drilling cracked holes a bit larger, you might consider countersunk stainless steel washers, as used in aircraft, as an alternative to screws with larger heads:
 http://www.aircraftspruce.com/catalog/hapages/stainlesswashers.php

These can be painted of course and will give broader support with substantial sealing surface.

all the best,

bumper
bumper
"Yonder" '05 MB
"WLDBLU" glider trailer
Re: Expansion, Contraction, Sealing and Moisture Integrity of corne
Reply #2 –
Yahoo Message Number: 48446
Quote
I've waited for current postings on this subject to subside before commenting.  That's happened, so this is my second of two postings
on  this subject, updating comments based on my training and experience:

Quote
May your touch-up paint never dry up in the bottle, Don McG
Don, I want to thank you again for sharing your knowledge and experience; it is invaluable! I have a couple questions, perhaps you can shed more light on a few things.

1. Do you have any photos illustrating the problem areas and remedies  that may make the issue more clear? If you do, I think the group  could benefit from them. I have to admit that I've had trouble  visualizing the trouble spots in some of the descriptions. I think I  understand most of your post, but as they say, "a picture is worth a  1000 words"! I for one, would welcome any tutorial photos; if we need  to clean house to make room for them, I think there are a lot of  pictures could be deleted. (Andy, what do you think, is a New Year  time to clean house with some of the old, old pictures?) 
2. I have a 2003, 26.5' LD probably built in May of 2003. If there  are cracks in the paint along the edges "End Caps", does that mean  there is potential water leakage? I don't really see any sealant  along the edges of the "End Caps". Does that mean I have the newer  kind of sealent tape? 
3. What is your opinion of installing a small cap over the joint  between the uppper and lower "End Cap" similar to what LD started  doing in the 2004 models? It would hide the unsightly cracked seam  that opens and closes. Has anyone retrofitted one to their rig? 
4. Any chance of you putting on a seminar in the future? It would
 sure be extra motivation for me to make the big shindig in Cheyenne, but then again, maybe some folks wouldn't want me motivated to attend, I'm already scheduled to be camped behind the "yellow tape" if I show up!

Thanks again Don, Steve K. (camping in cold & snowy Ohio for the next 4 months!)
Steve K

2003 Mid-bath
Re: old photos
Reply #3 –
Yahoo Message Number: 48449
"I for one, would welcome any tutorial photos; if we need to clean house to make room for them, I think there are a lot of pictures could be deleted. Andy, what do you think, is a New Year time to clean house with some of the old, old pictures?"
 We're currently at 48% of capacity in the Photos section, so there is certainly room for pictures of end cap problems and solutions. I periodically go through the photos and weed out obsolete ones (and I always delete the "full size" images that can take up hundreds of K apiece), so we're in pretty good shape.

Andy Baird
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"
Re: Expansion, Contraction, Sealing and Moisture Integrity of corne
Reply #4 –
Yahoo Message Number: 48475
Quote


Hello fellow LD owners, I've waited for current postings on this subject to subside before commenting.  That's happened, so this is my second of two postings

If drilling cracked holes a bit larger, you might consider countersunk stainless steel washers, as used in aircraft, as an alternative to screws with larger heads:
 http://www.aircraftspruce.com/catalog/hapages/stainlesswashers.php

These can be painted of course and will give broader support with substantial sealing surface. all the best, bumper
Hello 'Bumper', That was one of the possible configurations I looked at.  If I use a countersink washer and screw, either the washer will have to be thick enough to contain almost all of the countersink screw head, or, the screw head countersink will have to extend out of the washer countersink.  That would be the only way I could see to minimize the hole enlargement without loading a side of the enlarged hole with the edge of the countersink when the ABS End Cap grows and shrinks.

As I see it, the purpose of the revision is to let the ABS End Cap move with thermal expansion / contraction without loading the sides of problem screw holes and without letting in moisture.

It may be that a flat washer that is water tight to a stainless pan head Phillips screw head and also to the ABS End Cap outer surface, yet allowing movement between the washer and the End Cap, will be required for use with an enlarged screw hole.  If the simple fix does not work, I'll work up a trial using a turned-down diameter stainless fender washer with Eternabond tape as the sealant material.  It sure would be nice to find the simple fix works OK, though.
 When something good or bad shows up on our LD, I'll post the results of what I'm doing.

Don McG PS.  If any readers have localized sealant worries, that Eternabond tape is easy to use temporary waterproofing. Some even use it for extended 'temporary' time periods.

However, just enlarging the hole in the ABS and using a larger pan head stainless screw, installed with just enough sealant to waterproof the screw threads is an easier fix - if it works.
Re: Expansion, Contraction, Sealing and Moisture Integrity of corne
Reply #5 –
Yahoo Message Number: 48479
Quote
  I've waited for current postings on this subject to subside before commenting.  That's happened, so this is my second of two (snip) Don McG

Don, I want to thank you again for sharing your knowledge and experience; it is invaluable! I have a couple questions, perhaps you can shed more light on a few things.

1. Do you have any photos illustrating the problem areas and  remedies that may make the issue more clear? If you do, I think the  group could benefit from them. I have to admit that I've had  trouble visualizing the trouble spots in some of the descriptions.
 I think I understand most of your post, but as they say, "a picture  is worth a 1000 words"! I for one, would welcome any tutorial  photos; if we need to clean house to make room for them, I think  there are a lot of pictures could be deleted. (Andy, what do you  think, is a New Year time to clean house with some of the old, old  pictures?) 
  DCMcG: I have no digital photos of the problem areas.  I was at our  LD in winterized storage yesterday for its bi-monthly exercise, so  won't be there for a while.  It's raining meows and woofs today  anyhoo.  I'll take two fotos next time and post them.  In the  meantime, here is how to find the likely screw holes in your LD.
 Walk up to the driver's door, as if you were about to open it.  Look  up at the End Cap where it changes from horizontal at bottom of  overhead cab to vertical at body sidewall.  Those two screws right  near the corner are the likely ones.  Then look at the vertical End  Cap to your right.  There are one or two screws on each flange at the  street end (bottom) of the end cap.  Those are also likely ones.
 This same location on the bottom of the coach rear end caps are also  likely ones.  The others are at the eye level joint at rear end caps.
 Yours may or may not have any problems - Certainly, not all do.

Quote

2. I have a 2003, 26.5' LD probably built in May of 2003. If there  are cracks in the paint along the edges "End Caps", does that mean  there is potential water leakage? 
  DCMcG: No, definitely not.
 
Quote
I don't really see any sealant along the edges of the "End Caps".
 Does that mean I have the newer kind of sealent tape? 
  DCMcG:  Yes, I believe so.  (and this is based on my looking at many  LD, where I have found that the 2001 and somewhat earlier have more  space between the aluminum side panels and the inner surface of the  end caps than 2003 and later LD.)  On your LD, you will find sealant  showing under the end caps where there are joints in the aluminum  side panels, but probably not along the remainder of the end caps.
 What you see is how your LD was designed and built.  Essentially,  those are not 'cracks in the paint' but just paint on two parts that  are almost but not quite in contact with each other.  I don't think  you should try to fill those with paint or sealant, as they are how  the mothership intended them to be.

Quote

3. What is your opinion of installing a small cap over the joint  between the uppper and lower "End Cap" similar to what LD started  doing in the 2004 models? It would hide the unsightly cracked seam  that opens and closes. Has anyone retrofitted one to their rig? 
  DCMcG: Keep in mind that the later models with the cap strip(which  started sometime in 2003)do not have a joggled overlap joint.  If you  look closely at yours and see the upper end cap overlaps the lower  end cap, then I don't think the cap strip is applicable.  I do  suggest that you look closely at your end caps near that joint and  make sure they are not at all 'loose' e.g., securely bonded.
 Remember that 'frolic of my own' on which I'm embarked and contact  Steve Newton at the mothership if for the 'real deal' advice.  There  is no better source.

Quote

4. Any chance of you putting on a seminar in the future? It would
 sure be extra motivation for me to make the big shindig in Cheyenne, but then again, maybe some folks wouldn't want me motivated to attend, I'm already scheduled to be camped behind the "yellow tape" if I show up!
DCMcG: A seminar is an excellent idea - but for maintenance and owner repairs, I strongly believe that only the mothership should provide that data.  One seminar that an owner would do justice to would be Andy on interior personalizing changes.  And, I'm sure there are other owners that could 'seminar' changes such as floor coverings, tow light wiring, wall and window coverings, and electrical and electronic revisions.  Our LD has a full load of suspension changes, but the presentation of why and how for that subject is one for experts such as Henderson's Line Up or Erik's RV, not uvfsvt.
The seminar subject is one that I hope the Cheyenne coordinators have kicked around!

Quote
Thanks again Don, Steve K. (camping in cold & snowy Ohio for the next 4 months!)
DCMcG:  Hmm, cold weather camping, eh?  Perhaps you'd be interested in that same size furnace replacement that has 10,000 more BTU/hr and uses two motor fans - one for combustion air and one for heated air? It does have less noise on startup than the ones in our 23 and 26 ft LDs - Though it does require one more heated air outlet.
May the only ice in your LD be in the freezer, Don McG
Re: Expansion, Contraction, Sealing and Moisture Integrity of corne
Reply #6 –
Yahoo Message Number: 48484
Don,

The CSK SS washers I referred to are very thin, but strong. The countersink area is stamped in, so extends into the material to be fixed. This means that you'd need to enlarge the original hole and preferably countersink it also. This should be quite workable as the OD of the washer is relatively large.

It would also be possible to use a thin rubber (say diaphram material) between the washer and the plastic. This rubber would ideally extend into the countersunk area of the underlying plastic so there would be no direct contact between the screw or CSK washer.
This would both provide a permanent, flexible seal, and also allow thermal expansion/contraction of the plastic. A similar method is sometimes used for mounting Plexiglas windshields, where the holes are overdrilled and thin cork gasket material (or similar) is used under the washers. It is also good to just gently tighten such fasteners (g).

all the best,

bumper (without a single crack in Yonder - - yet)
bumper
"Yonder" '05 MB
"WLDBLU" glider trailer
Re: Expansion, Contraction, Sealing and Moisture Integrity of corne
Reply #7 –
Yahoo Message Number: 48514
Quote
I have no digital photos of the problem areas.    In the meantime, here is how to find the likely screw holes in your LD.
4. Any chance of you putting on a seminar in the future?
 DCMcG: A seminar is an excellent idea - but for maintenance and
owner repairs, I strongly believe that only the mothership should provide that data.

Quote
Thanks again Don,

Steve K. (camping in cold & snowy Ohio for the next 4 months!) DCMcG:  Hmm, cold weather camping, eh?  Perhaps you'd be interested in that same size furnace replacement that has 10,000 more BTU/hr
and  uses two motor fans

DCMcG, thanks again for the information. I'll be keeping an eye on the "End Caps" though in my mind they are the "edge caps" .
 Regarding the seminar idea, I understand where you're coming from by your suggestion the factory should be the source of information, particularly in this situation. I've noticed how you've always recommended folks check with the "mothership". Maybe I'm wrong, but somehow I don't think the factory will send anyone to put on these kinds of seminars.

One other note. I'm not "camping" in Ohio for the winter. The LD is hiberanting with the woodchucks from December through April. I am home, and almost hibernating!

Steve K. (may your New Year be one of health, happiness, and adventure)
Steve K

2003 Mid-bath
Expansion, Contraction, Sealing
Reply #8 –
Yahoo Message Number: 48457
In a message dated 12/29/2004 10:01:44 AM Central Standard Time, no_reply@yahoogroups.com writes:

Quote
I'm already scheduled to be camped behind the "yellow tape" if I show up!
Is this the area you are going to set up your "FREE FINISH FIRST APPLICATION SHOP"(g)?  Put me down as first in line.

John K

[Non-text portions of this message have been removed]
 
[Life With A Lazy Daze RV] Re: Expansion, Contraction, Sealing and
Reply #9 –
Yahoo Message Number: 48478
Quote
I'm already scheduled to be camped behind the "yellow tape" if I show up! Is this the area you are going to set up your "FREE FINISH FIRST
APPLICATION  SHOP"(g)?  Put me down as first in line.

Quote
John K
John, you sly dog! What a great idea! I wonder if I should enroll as a FF distributor and bring a trailer loaded with product to Cheyenne? I have long admired those sales folks at the auto shows demonstrating polish, miracle absorbing cloths and window cleaning stuff. My wife makes sure my credit cards are left behind when I go to those events.
 Do you think the folks who like the other polishes will be there too? How about it Dick (USMC)down in Florida?
 Steve K. (with all that FF on my LD, the snow just slides right off!)
Steve K

2003 Mid-bath