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Trim sealant

The metal trim that runs the length of the coach ( and over the front and rear caps ) has a white sealant that bonds the trim strip to the fiberglass.  A slit is developing, the trim is separating from the fiberglass by about 1/32.  It appears that the fix would be to remove all the metal trim ( boy I hate to think of that ) , clean old sealant off trim and fiberglass, replace trim and reseal.
Any one got a better, and less intensive solution ?
Gary B

AND.... What do you use as a solvent to remove the white sealer and the silicon that has also been used ?

Re: Trim sealant

Reply #1
I have been using acetone to remove everything that is left after removing decals and trim with the white sealer. Works best with a rough cloth like an old towel. Have to use a different spot on the cloth every few seconds as it clogs. Make sure to wear gloves and do it outside. Good to have a fan for the vapors. Gallon is about $18 at HD.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Trim sealant

Reply #2
Pierce, I thought of that but won't acetone remove the paint from the metal trim ?
Gary B

Re: Trim sealant

Reply #3
Gary,
I've used a product (from HD) called "Motsenbockers LiftOff Silicone Latex Caulk Remover" in a little red bottle (liquid, not aerosol).
I works OK and is safer for paint.  It weakens the silicone so it can be scrapped easier.  Still no fun and time consuming.
In your case I would consider just applying a new bead of silicone over the old stuff (assuming it's silicone) rather than removal and reinstall.
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: Trim sealant

Reply #4
What I had in mind was removing the old dirty looking sealant and using LEXEL clear to replace it. Over the years the original white factory sealant has browned and separated and in places Silicone has been placed over it to seal damaged areas and it just looks bad.  In trying to scrape out old sealant it is real easy to scrape the paint off the metal trim and I also do not want to damage fibreglass and decals.
Gary B

Re: Trim sealant

Reply #5
Sure - take it to Xtreme. Less intensive for you, more intensive for your wallet...
The selected media item is not currently available. Dave Head & Megan Westbrook
Titusville, FL - The Great Outdoors
'98 270 buying this month
Toad is a 2018 F150 XLT

Re: Trim sealant

Reply #6
Dave, What is your interest rate for about 22 grand for 50 years ? :)
Gary B

Re: Trim sealant

Reply #7
Gary,

It didn't in my case but would want to try it on a non-visible piece first.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Trim sealant

Reply #8
Gary,

I've been using Goo Gone on a cloth that I saturate, wrapped around the end of a plastic scraper. It removes that discoloration quite easily without damaging the bond of the sealant -- in those areas where the sealant is still good and attached, of course. But I also have a few areas where it has pulled away -- and will probably just re-apply white silicone in those spots.

What I'm searching for now are the correct stainless-steel Robertson screws (like those that hold our trim on in the basement bays) with a taper under the head -- to fit almost flush with the molding. The simple phillips head screws FT used on all of this metal molding won't tighten correctly in some areas, and there is rust showing on some of them.

I'm going to replace all of the screws with the Robertsons on the exterior moldings.

Home - Goo Gone

Robertson Website - Home Page
Michael
1995 U300SE CAT 3176B Build # 4612 ("Marvin")

Re: Trim sealant

Reply #9
Michael,

I'm going to replace all mine with stainless oval head screws. Have not been able to find any with square drive, only with phillips. The good part is that they are dirt cheap on ebay. I have ordered several boxes and have been pleased with the quality. See example at: Sheet Metal Screws Stainless Steel Phillips Oval Head 8 x 3 4" Qty 100 | eBay

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Trim sealant

Reply #10
Michael, Can you find an OSH hardware or a large ACE hardware? You may find some thing use able there. Sometimes I have had to go to a larger size screw or same size longer screw. When you go larger, you have to make the countersink deeper. If you are finding rusty screws on the trim along the top of the bay doors, the flooring edge is probably rotten. A long screw usually will find good wood.  Also , all of the old sealant around those trim pieces,(above the bay doors , over the end caps, and especially the roof trim, should be dug out , cleaned , and re caulked.  And, don't buy the cheap stuff to replace it.

On another subject. Don't start diddling with adjustments on the Power Tech until you have done more research. When you have time, give me a call and I will explain.

Gary O
Gary O
2000 U320 4210

Re: Trim sealant

Reply #11
I found when scraping thing off it is best to use plastic razor blades. Here is a site they work great.    http://www.scraperite.com/

 


 
Jimmy Freytag,  Ardmore, Ok
1999 36ft U320. — -SOLD—-
1988 40ft GV        1990 36ft U280
1993 40ft U280      1996 36ft U280
  TRAVEL WHILE YOU CAN THE TIME WILL COME
            WHEN YOU NO LONGER CAN.


Re: Trim sealant

Reply #13
Gary,

The simple phillips head screws FT used on all of this metal molding won't tighten correctly in some areas, and there is rust showing on some of them.

I'm going to replace all of the screws with the Robertsons on the exterior moldings.

Home - Goo Gone

Robertson Website - Home Page

If the screws you removed had rust on them, that is an indication that you have had some water seepage there. I would recommend filling the holes with a small dowel with a bit of glue, bamboo skewers work well also. Otherwise you will have to use a larger sized screw.


Roland
1993 U280 4341
2010 Jeep Liberty
The Pied Pipers

Re: Trim sealant

Reply #14
Pierce, I can't believe those prices for stainless. I'm ordering now.
Jimmy, maybe I can finally remove silicone without scarring the paint.
Thanks to you both.
jor
93 225
95 300
97 270
99 320

Re: Trim sealant

Reply #15
Gary,

Don't use Lexal unless you never want to remove it.  I used it on a large boat window and it was unbelievable how hard it was to scrape off the aluminium frame.  A good caulk like Boatlife from West Marine will work, and to prevent a mess, mask the area off BEFORE removing the trim - makes it easy to mask off well.  Run finger or something with a small radius along the trim after reinstalling it then remove the tape.  Nice and neat with no mess.


Keith
Keith, Joyce & Smokey the Australian Cattle Dog
1995 U320 SE Extreme 40' WTBI Build # 4780, with a Honda CR-V hopefully still following behind.
Motorcade # 17030
FMCA # F422159

Re: Molding attachment screws

Reply #16
Gary,

Attached is a pic of the worst two -- as far as the slight rust. I just assumed it was because FT didn't fit S.S. screws, but just painted the tips of carbon steel ones, and the discoloration is due to moisture getting through that paint over the years.

I don't think I have a floor edge rotting problem. My reasoning is if I did, I'd see a lot more evidence like iron-oxide stains making their way into or through the caulking at various places around the Coach.

Whattya think? 
Michael
1995 U300SE CAT 3176B Build # 4612 ("Marvin")

Re: Trim sealant

Reply #17
Gary,

I've been using Goo Gone on a cloth that I saturate, wrapped around the end of a plastic scraper. It removes that discoloration quite easily without damaging the bond of the sealant -- in those areas where the sealant is still good and attached, of course. But I also have a few areas where it has pulled away -- and will probably just re-apply white silicone in those spots.

Home - Goo Gone

Robertson Website - Home Page

I suggest that you use urethane rather than silicone caulk unless you plan on removing the part soon. Urethane has much better adhesion and is what was used by FOT originally. There are also hybrids, urethane/acrylic etc that work fine but Dicor or Sika urethane are the ones used for years and should be readily available. They come in Vertical and Self Leveling grades so be sure you get the right one for its intended use. You will find Dicor at RV stores, Sika at Lowes or Home Depot.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: Trim sealant

Reply #18
Michael, The screws used by FT have a white coating baked on to the heads.  You can buy screws with white heads as replacements.  If the threads are rusty them water has been behind the trim and it needs to be resealed and while you are at it replace the screws with either the white head ones or stainless.
Gary B  ( T Think Gary O told you about rotting floors )

Re: Trim sealant

Reply #19
I suggest that you use urethane rather than silicone caulk unless you plan on removing the part soon. Urethane has much better adhesion and is what was used by FOT originally. There are also hybrids, urethane/acrylic etc that work fine but Dicor or Sika urethane are the ones used for years and should be readily available. They come in Vertical and Self Leveling grades so be sure you get the right one for its intended use. You will find Dicor at RV stores, Sika at Lowes or Home Depot.

Kent, any chance this stuff will bond where silicone has been?  I know it's the kiss of death for painting even when scraped off seems like specialized solvent is required for full removal.  Like Gary I was thinking about using Lexel then got to thinking about the time I fixed a rocking toilet on an uneven tile floor with it.  I had to use a sawzall between toilet and tile to remove it a few years later. 
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Trim sealant

Reply #20
Silicone sealant does not contaminate surfaces as bad as silicone spray and other forms of silicone. The best way to remove residual silicone is scrubbing with detergent and lots of rinsing. Solvent doesn't really remove silicone contamination but it does remove the rubbery part of the caulk. Just mechanically remove the silicone caulk with an appropriate mechanical device, plastic scraper, remove any visible residual caulk with solvent and then scrub the area thoroughly with detergent.

I have used and like Lexel. It is a really good adhesive as well as sealant however the pure urethane caulks seem to have a more manageable body resulting in a better finish look. I think urethanes are also more chemical resistant. They too are a good adhesive but not as hard to remove as Lexel, 3M 5200 may be the exception. Most of the white caulk on my 93 was urethane caulk, probably Dicor, according to the old timers at FOT. Urethanes are very moisture sensitive so substrate must be completely dry. Lexel can be used on damp surfaces.

Lexel can be cleaned up with paint thinner/mineral spirits. Urethane requires harsher solvents such as lacquer thinner or toluene for cleanup.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: Trim sealant

Reply #21
Thanks Kent,

It's great having a polymer expert on the board.  I'm hoping to do this one time and may well use fast cure 5200 and deal with removal if and when necessary.  Will prep, tape off and tool a minimal bead. 
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Trim sealant

Reply #22
Gary,

Attached is a pic of the worst two -- as far as the slight rust. I just assumed it was because FT didn't fit S.S. screws, but just painted the tips of carbon steel ones, and the discoloration is due to moisture getting through that paint over the years.

I don't think I have a floor edge rotting problem. My reasoning is if I did, I'd see a lot more evidence like iron-oxide stains making their way into or through the caulking at various places around the Coach.

Whattya think? 

After I bought my coach, I did find a section of trim where the caulk had pulled loose.  I think it had been that way for a few years.  FT did use painted stainless screws for the trim strip.  Behind the trim strip though is a lot of other rather long (1 3/4"?) steel black Phillips head screws that hold on the door hinges, fenders, and panels.  The trim strip is only caulked at the top and any water or moisture behind the trim should be able to escape or drain out the bottom of the strip.  If the caulk is loose though allowing water behind the strip, it is likely to stay there for awhile depending on the climate you are in.  I found some rusty screws and rotted wood behind the trim strip where the caulk was loose.  I forced some epoxy caulk into the holes where the screws did not hold, however a simpler solution may have been to use longer screws.  There are good and poor grades of stainless steel, and stainless screws.  Contrary to the name stainless, some stainless will develop a brown stain but it is mostly a cosmetic thing.  My painted trim screws did not have any brown stains.  Also no stains below the trim strip but some of the black finish screws were very rusty. 
Jerry Whiteaker former owner 96 U270  36' #4831 Austin,TX-Owner Mods LCD TV w/front cabinet rebuild - LCD TV bedroom - Dual Central AC, either can cool coach w 30 amp - Skylights at roof AC openings - Drop ceiling for ducting of AC - Shower skylight white gelcoat/wood/epoxy frame - Air Springs/Shocks replaced - 2014 CRV - 8K Home Solar - Chevy Volt