Proflex on Roof Radius Joint

[Americanrascal]

I've been a real believer in using Geocell Proflex for the roof radius joint on our Adventurer for quite some time now ever since AZ Expert provided good education on the use and product. I keep a close watch on my radius joints and roof seals inspecting and repairing sections at least 2 X and sometimes 3 times each year. Each joint repair requires cleaning and preparing the joint for a new application.

Last week I did a close inspection of the roof joint and paying close attention to a 3' section over the drivers side front window area which had shown deterioration and weakness when I inspected a year ago. I applied new geocell to that section at that time. I cleaned the section out well and applied new Geocell Proflex as I had done before on other short sections. I always allow at least a 7 day setting and cure before I move the rig to allow for a good cure.

I was surprised last week when I found the Proflex was not adhering to to the filon or gutter joint. Not only was it not adhering but the filon itself was loose in the joint. That puckered me up and I got busy cleaning the joint out and preparing to apply new Proflex to the joint.

To make things worse, I always use (and have been every successful with it in the past) a pneumatic caulk gun for application of Proflex. As I started resetting the joint with the tip of the application tube set well down into the joint, the application tip suddenly ruptured and broke off shooting about 3/4 of the tube of Proflex down the side and onto the drivers side window. Somehow I got the mess cleaned up with little noticeable damage to the rig

As I inspected other areas and joints around the motorhome in lower areas I found the bead I installed last year in other regularly checked areas also had not adhered and were coming away from the joints to be sealed.

I had always felt that Proflex might be superior to the Manus Bond that I had originally used. But Manus Bond did not ever reveal a failure to adhere anywhere I applied it on the body. Anyway I am scratching my head on this one and may go back to using Manus Bond. Wondering if anyone else had run across similar issues with Proflex????

[BobC]

Any chance it was out of date? I see that Proflex specifies a one-year shelf life. Other than that, the only thing Geocel lists as an adherence problem is the presence of silicone from an earlier application:

https://www.geocelusa.com/resources/faqs/

[creativepart]

I was going to say it sounds like there had been silicone in the drip rail previously and that was the issue.

I used Manus Bond 75 on my front cap side area. I hated using it due to the mess but it’s certainly lasted for going on 3-years.

[bigb]

Along with the date as mentioned there may have been residue of a past sealant. I think it's really hard, almost impossible to get it as clean as factory new. When I did mine I was repainting the radius edges so I really, really cleaned things up and after I finished I let it cure for a month before driving, although I don't think that was necessary, I just didn't need the rig for that long. Granted it's only been 10 months but it's holding very tightly and I believe it's due to the extremely clean surfaces that I was able to do since I was painting anyway. I actually scrubbed as much as I could with razors, Scotch Brite pads and lacquer thinner multiple times and also ran a Scotch Brite Roloc disc on a die grinder through after that. On the aluminum side there is a little 1/8" or so step in the side of the channel that is very hard to get clean, a utility knife works best followed by thinner and Scotch Brite pads. Of course the Roloc got it spotless but also removes the paint on the filon side and will burn thru the gel coat if you stay in one place too long.
I understand that the main reason for using the Proflex is not because it is superior for the job but because it is available in clear for coaches that are painted up there, if the appearance is not super important to you maybe you could try a different product. Even the black Proflex is UV resistant while the clear is not. My coach had some black Proflex applied inside the refrigerator cabinet and that stuff held on very well, I could not really get it off, but I suspect it was from the new, clean surface when it was originally applied plus no weathering inside the cabinet.

[Americanrascal]

No silicone ever used (unless someone put it on when it came off the production line). The area I cleaned and had installed new Proflex was the original set from the factory which I suspect was Manus Bond. I bought the tubes of Proflex less than a year ago.

I cleaned the area (the joint trough) very well before applying new Proflex- on all areas I used the stuff.,

I hate it because I liked the Proflex and had high hopes, but if I'm going to use it it has to do the job- the thought of loosing roof scares me. I may just revert to Manus Bond. I've also had a recommendation to use Loctite Polyurethane Door, Window and Siding as I have been told of success with it. Thinking maybe run about 1 1/2 ft of each to see what does best.

[BobC]

Originally Posted by Americanrascal

I bought the tubes of Proflex less than a year ago.

Even so, they could still be out of date. Here's how to check the manufacture date. This is from the previously linked Geocel FAQ page:

How do I read the lot/batch code?

Lot numbers are an important component in the manufacturing process as a tracking mechanism for inventory, complaints, sales history and quality control. It is also a beneficial tool for our customers as the lot numbers identify the time frame for when a product was manufactured.

Most of our lot numbers consist of an eight-digit, alpha-numeric code. The first two letters in the code indicate where the product was manufactured. The next three digits represent the day within the year. For example, a product with a lot number of ER1016RB is translated as the 101st day of the year, with the “6” representing the year—2016. Or, said another way, the product was manufactured in early April of 2016. The location of the code can be found near the bottom of the packaging on either the cartridge plunger or around the UPC code area.

[Americanrascal]

Good Info Thanks!

[Americanrascal]

Tube I have left from that batch says ER2480BF-- so I assume its about 1 year and a half old as of today. What I replaced had been on there about 1 year and I recall it was purchased at the same time. That would indicate it was a relatively fresh batch that I applied and eventually failed it seems.

Found the shelf life paragraph.

I looked on their web site and said a shelf life of 1 year. This the one I have may be at the end of its shelf life, but the one that failed was relatively fresh

[BobC]

How well the surface was cleaned could be a factor as well.

Since I'm not concerned about color, I think I'll stick with Manus Bond. Unfortunately, I bought extra and am going to have to toss some in the trash.

[Americanrascal]

Thanks all. I've been getting all the areas prepped and cleaned out well. Will try fresh Manus Bond again and a short trial on the Loctite Polyurethane to see if it has good adherence, life span and sealant capability. Fingers crossed

[Ray,IN]

Manus Bond 73-A is silicone based, other numbered sealants are not silicone based.
You may purchase a specific silicone remover spray if working with an area previously sealed or treated with silicone. Even if you remove every bit of silicone you can see, there will still be a remaining residue that must be removed before new sealant will adhere properly, even more silicone sealant.

[JLUSoCal]

I think we're referring to Manus Bond 75 that is not silicone based - 75-AM Ultra Clear

And I would agree - I avoid silicone because the replacement of it is a pain in tight quarters like just about everywhere on a motorhome!

[Americanrascal]

Yep 75 not 73 A

[jspringator]

I used 3M4200 fast cure on one side of mine last September. A 2 foot section over the passenger window has already failed the press check. I'm going to use Locktite PL S40 to reseal the bad section and do the other side. It doesn't come in black, so I'm going to use Silkiflex 291 to seal the window. These 2 sealants were the top performers in a Practical Sailor test I found online. Practical sailor is like consumer reports for boats. The commentary on 3M4200 said it was hit and miss on adhering to aluminum. Yup.

[bpcannan]

Do you have insight on my problem...
2010 Journey Express 34Y...front cap to roof area issue
flat part of roof has what appears to be the original manus bond sealant and looks in great shape - cannot find cracks or anything - HOWEVER - I have just started to develop a water seepage issue where the roof curves over. I found some cracks and gaps so I cleaned out the old, wiped thoroughly with mineral spirits and goof-off, let it dry. The using the call-out sheet I applied and finger trowled for smoothness the Stone Mason sealant (0944-01-000) from the winnebago parts catalog to no avail. I have done this twice and can't seem the fix the issue. The sealant I am using is Sealant E which they say can be a substitute for Sealant C. I have watched some AZExpert and he speaks of Proflex Geocell. I am confused and a bit frustrated. Any insights that you can offer? Should I go with Proflex? Should I just use the Manus bond. Any help or thoughts are appreciated. I have been all over my roof on my hands and knees exploring all the seals around everything up there and the water issue Only manifests itself in the driver side cupboard above the driver side window and the cupboard on the passenger side above the door - so I have assumed it is coming in thru the radius where the cap meets the roof. My radius that runs the length of the coach is in great shape so I have ruled that out.

Thanks for any help.
Brian

Originally Posted by Americanrascal

I've been a real believer in using Geocell Proflex for the roof radius joint on our Adventurer for quite some time now ever since AZ Expert provided good education on the use and product. I keep a close watch on my radius joints and roof seals inspecting and repairing sections at least 2 X and sometimes 3 times each year. Each joint repair requires cleaning and preparing the joint for a new application.

Last week I did a close inspection of the roof joint and paying close attention to a 3' section over the drivers side front window area which had shown deterioration and weakness when I inspected a year ago. I applied new geocell to that section at that time. I cleaned the section out well and applied new Geocell Proflex as I had done before on other short sections. I always allow at least a 7 day setting and cure before I move the rig to allow for a good cure.

I was surprised last week when I found the Proflex was not adhering to to the filon or gutter joint. Not only was it not adhering but the filon itself was loose in the joint. That puckered me up and I got busy cleaning the joint out and preparing to apply new Proflex to the joint.

To make things worse, I always use (and have been every successful with it in the past) a pneumatic caulk gun for application of Proflex. As I started resetting the joint with the tip of the application tube set well down into the joint, the application tip suddenly ruptured and broke off shooting about 3/4 of the tube of Proflex down the side and onto the drivers side window. Somehow I got the mess cleaned up with little noticeable damage to the rig

As I inspected other areas and joints around the motorhome in lower areas I found the bead I installed last year in other regularly checked areas also had not adhered and were coming away from the joints to be sealed.

I had always felt that Proflex might be superior to the Manus Bond that I had originally used. But Manus Bond did not ever reveal a failure to adhere anywhere I applied it on the body. Anyway I am scratching my head on this one and may go back to using Manus Bond. Wondering if anyone else had run across similar issues with Proflex????

[bigb]

Could it be your clearance marker lights?

[bkg]

Originally Posted by Americanrascal

I've been a real believer in using Geocell Proflex for the roof radius joint on our Adventurer for quite some time now ever since AZ Expert provided good education on the use and product.

I have just redone my cove sealant. I had used Geocell just over a year ago but found separation from the filon roof in sections in February of this year. This time I cleaned out the entire length of both sides of the roof cove and decided to go with the Manus Bond 75 AM. I followed AZ Expert steps using mineral spirits to assist in releasing the old sealant.
I believe there were two causes of my first cove sealant failure; the Geocell cartridge wasn't the freshest - 10 months old and the other cause was the residue of the mineral spirits. Originally I used rag soaked with mineral spirits tucked onto a putty knife blade. I believe I did not allow enough flash time for the mineral spirits to evaporate. This possibly combined with the "older" shelf date of the Geo Cell resulted in the premature failure. This time for my cleanup I used mineral spirits in a trigger-type pump sprayer. This worked extremely well. I started in the morning just after the dew burn-off. Swabbed the channel with the mineral spirits and left it to evaporate. I returned the following day to apply the Manus Bond 75 AM. I started around 3pm and finished applying the sealant to both sides by 5pm. This was back in March and on clear weather.
The sealant did lay-in better but found the Manus Bond was easier to "tool" after 4pm and I believe this was because of the lack of the harsh heat at 3-4pm curing the Manus Bond - I'm sure glad I didn't start right after lunch like I had planned.
I ordered 4 tubes of the Manus Bond from Amazon, 2 tubes were dated and 2 were not. No lot numbers were found on the tubes. The dated tubes were very fresh made in January 2022. I got lucky and all 4 tubes were equal in application.

Just got back from a 1200-mile trip and checked the cove sealant, still very tight. Hoping to get 2 years or better out of this application.

Bobby

[bigb]

Originally Posted by bkg

Just got back from a 1200-mile trip and checked the cove sealant, still very tight. Hoping to get 2 years or better out of this application.

Bobby

My original, which may have been Manus, lasted 10 years in outdoor storage. As I noted earlier my prep before the Geocel was 100%. If the Geocel does not hold up I will be looking at Manus. It's holding tight but hasn't been quite a year yet. Will look forward to updates on yours.

[bpcannan]

Originally Posted by bigb

Could it be your clearance marker lights?

Wow, I had not thought of that. Will be checking them in the morning as I did not focus on them at all.

Thank you
Brian

[bkg]

Originally Posted by bigb

My original, which may have been Manus, lasted 10 years in outdoor storage. As I noted earlier my prep before the Geocel was 100%. If the Geocel does not hold up I will be looking at Manus. It's holding tight but hasn't been quite a year yet. Will look forward to updates on yours.

I think Geo Cell is a good product. I often used it on my prior RV's with good results. I really believe the premature failure of the Geo Cell had to do with the age of the product, some of the ingredients solidify as it ages in the cartridge. This is true with nearly all sealants and adhesives.
As for updates, you bet I will post an update if I don't get at least 2 years on this application.
For the FWIW, I have been testing other sealants (not on the RV) such as Henry 212 and a BASF urethane. Performing tests on metal sheeting of cargo trailers that spend 100% of the time exposed to the elements. That takes time too.

Bobby