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Posted By: rebar Softer, longer lasting Rain Gutter Seam Sealer? - November 22nd 2016 3:22 am
I'm trying to find a seam sealer more flexible and longer lasting to completely fill my rain gutter than the typical 3M 08505 Fast’n Firm seam sealer. Since my van is a work van, I'm more concerned with preserving it, than a nice shinny paint job.

Has anyone used NP1, SikaFlex 221 or Vulkem 116 instead of 3M Fast’n Firm I keep reading cracks?

Thanks!

https://www.vanning.com/threads/ubbthreads.php/topics/384999/1

https://www.vanning.com/threads/ubb...replacing-rain-gutter-sealant#Post671641

https://www.vanning.com/threads/ubb...a-rain-gutter-rust-on-95-e350#Post716881





Posted By: Ram4ever Re: Softer, longer lasting Rain Gutter Seam Sealer? - November 22nd 2016 9:45 am
You and me too!

I used 3M's Fast'n Firm on my van, and despite what appeared to be an initial success, which you read about in the one thread that I posted in, I eventually became totally disgusted by it.

It was difficult to apply smoothly in as large a drip rail as on my Dodge van, even in ideal application conditions, and then it failed within several years despite substantial surface preparation. As with many materials targeted towards the automotive refinishing industry, it behaved very well for a year or so. But then it cracked in several areas of the flat runs in both drip rails, then peeled up in those spots just like dried pond mud into Pringle's potato chip shaped edges, allowing water to enter and get underneath it. I'm gritting my teeth at how much cleanup and rust repair that's going to require...

Though it wasn't used in a drip rail application, I didn't have especially good results with the 3M 8656 brushable seam sealer either. It split open in multiple areas as it cured, despite proper preparation for the epoxy paint it was applied to. I even called the 3M support line about it to verify the preparation was correct and materials were compatible. It acted like it didn't like sticking to itself; almost as if it needed fibers mixed in to keep from tearing itself apart as it dried. I took it back for another, newer can, (-called 3M and had them run the date code) and it did the same thing, even on other non-epoxy surfaces. I'd used it with no difficulties 5 years or so earlier, so I have to wonder if it's been reformulated for lower VOCs?

The end results of all this is no more 1-part seam sealers for me!

Partially due to my already having the necessary applicator gun, I decided to go with the 3M 8307 2-part self-leveling seam sealer. I have several cartridges already, but the weather has deteriorated too much in Michigan to apply and paint it now, at least until I can get my van into a heated garage.
Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - November 22nd 2016 12:30 pm
Thanks Ram4ever.

Your not the first one Iv read having the same problem and Im surprised since I thought 3M was one of the best. And yes, its the low VOC as I read even ford factory had problems with later years.

There's a guy over on the sportsmobile forum that swears by the Vulkem. But I read Vulkem also changed their formula.

I just aired down my tires and got the van under a 7' door to do the work this winter. But at this rate and not feeling comfortable with the products, who knows what I will do.
Posted By: Ram4ever Re: Softer, longer lasting Rain Gutter Seam Sealer? - November 23rd 2016 5:08 am
It's certainly an area which bears some experimentation on small test panels prior to committing to a large surface, especially one which is laborious to clean out like a full size van drip rail!

I've had really great results with the 3M 2-part body panel adhesive, and pretty much swear by it, with the caveat that if your local jobber doesn't move much volume you'd better call 3M from the parking lot prior to leaving with it to verify that it hasn't expired! I've marched right back inside on several occasions, demanding an exchange, much to the chagrin of the embarrassed sales counter folks. Shelf life on these products typically doesn't exceed one year in climate controlled storage...

You've got to check; I had some 8116 once which wouldn't set for anything - despite my test panel (I was becoming quite cautious by then!) which should have been hard as can be inside of two hours, setting outdoors for a week in direct sunlight. I got a refund on that one and got fresher stuff (-called 3M immediately to verify the date codes...) and it worked perfectly; set up right on schedule and I was able to sand and paint within several hours.

The 3M support folks told me that the date codes require some research on their part, as on the 2-part materials, each part may have come from different lots or manufacturers, each with different expiration dates, so it's necessary to look up both parts separately! They do have quick enough access to the data that it can be researched comfortably in a phone call, and encouraged me to call any time I have any doubts at all. They really do want us to be successful.


8116 body panel adhesive is one of the materials used in current automotive production; it's good stuff. Most body shops will use 8115 instead, since it sets up a bit faster; they can throw paint on and get the repair out the door sooner to make room for the next car. 8116 is stronger though; it meets OEM specs.

It isn't especially well known, but the builder of the Flamed van (which was recently wrecked) told me he used body panel adhesive on his rocker panels when he built it in the 1990's, and those seams came out and remained show quality for the life of the van, with no print through or delamination. That van sadly ended up being a great test case; in the wreck pictures the panels held up wonderfully, despite damage to the body extending all the way forwards.

I did about 1/3 of the driver side of my maxi van with 8116 body panel adhesive, when I deleted a conversion window and cleaned up some other surface damage, and the results were awesome, and are holding strong.

If panel adhesive were at all flexible enough to flow out well, I'd be tempted to use it in a drip rail. Since it's considered to be an automatic seam sealer, it would certainly work to keep water out. But I think that it's highly likely that the purpose-formulated self-leveling seam sealer is more apt to meet our expectations.

I wish I'd been further along with my interior while the weather was good; I'd love to get the roof finished. I'm going to do it in stainless steel, and once that's done, I'll tend to cleaning the failed Fast'n Firm sealer out of the drip rails, and then I'll apply the 2-part self-leveling seam sealer. I'll be sure to post the results when it's complete, which may well be spring at the rate things are progressing.

So, I do give a thumbs up to the 2-part products, as long as the date codes are provably within the products intended expiration dates.


BTW, I feel for you on the low garage door; when I rebuilt the suspension on my van, it raised up so high even deflating the tires wouldn't allow it to fit in my garage! I had to save up and have a contractor cut the door opening taller, based on our measurements of my van, then add another vertical panel to the garage door!
Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - November 24th 2016 3:41 am
We sure must love our vans Ram4ever. I'm actually searching for another house with a huge/tall garage and less bedrooms since I divorced my X. You modified your garage to accommodate. My home is a split foyer, so I cant raise the door because of the bedrooms above.

I started digging the old seam sealer out today. It looks like most of it is in good shape and I'm wondering why I'm digging the good old toxic stuff out. So far it looks like the seam sealer failed right where the crimped side panel was folded over the roof panel or the very top of the gutter. In fact some of it is completely rusted away and separating.. I knew I was opening a can of worms but cant stand thinking water might be getting inside of a vehicle I spent so much time and money on. I made it about two feet until I cut my finger so I took a nap. More to come!

[Linked Image][Linked Image]
Posted By: Ram4ever Re: Softer, longer lasting Rain Gutter Seam Sealer? - November 24th 2016 6:11 am
A pole barn would be awesome. I originally had my sights set on a house up here which had a separate, heated, drive-through garage, but it was too far out in the stix for my other half's taste. Hope you find a winner!


Just to give you some idea of how the Dodge van roof and upper wall joint are structured, here is a cross section:
[Linked Image]

Water has to work to get through it, but it can, and once it does, it can travel quite a ways from where it enters to wherever it finds a way out, so digging out the entire drip rail is about the only way to be sure you stop any current or potential leaks.


And BTW, if you go with the 2-part 3M materials, here's is the type of applicator gun I got, the 3M #8571:
[Linked Image]

I picked it up on eBay for a really good price. It works really well. Each cartridge of adhesive comes with two mixing nozzles, but if you need more, the aftermarket mixing nozzles can be had inexpensively too.
Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - November 24th 2016 5:08 pm
A shouse would be nice until you wanted to sell it. Iv been watching the market for about four years with no luck. I dont want a pole barn with wood in the ground. But building one with a foundation would cost more than I could sell my place for probably.

Thanks for that cross section pic. There's so much going on there its hard to see exactly and imagine trying to rebuild that..
The reason I'm now wondering, is the vertical outside edge of the gutter doesn't look like it crimps the top on like I thought and could be eliminated to allow water to shed maybe?

Does anyone have a picture or drawing of the cross section of the fourth generation ford econoline gutter?
Posted By: Ram4ever Re: Softer, longer lasting Rain Gutter Seam Sealer? - November 24th 2016 6:58 pm
There are Vanners who have cut away the entire drip rail on both sides and welded it flat. I've seen a pictorial here, but it was a number of years ago. It's a lot of detail work, but it makes for a very modern looking update to a vintage van.


A pole barn may not need a massive solid foundation - one of my friends in Pennsylvania erected a big (30x20 feet) metal pole barn, with steel vertical posts bolted to J bolts embedded in separate concrete pads for each post, and the floor was dug out and filled in thick gravel. He keeps his tools, welders, corvette, and cigarette boat in it, and it's held up well for nearly 20 years now. I don't know how deep the concrete pads go, but it's got to be less yards of concrete than a full-blown foundation. The price of steel isn't exorbitant either; it was running 50 cents per pound when I was at Alro Metals in Ann Arbor the other day. It sure was a darn sight cheaper than the Copper bar I also bought, which was running $8.32 per pound!
Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - November 26th 2016 7:31 pm
Originally Posted by Ram4ever
There are Vanners who have cut away the entire drip rail on both sides and welded it flat. I've seen a pictorial here, but it was a number of years ago. It's a lot of detail work, but it makes for a very modern looking update to a vintage van.


A pole barn may not need a massive solid foundation - one of my friends in Pennsylvania erected a big (30x20 feet) metal pole barn, with steel vertical posts bolted to J bolts embedded in separate concrete pads for each post and it's held up well for nearly 20 years now.


Yeah, I'm all about concrete and steel and that type of construction your friend did is fine for storage, but would be difficult to insulate and finish out. By the time you add studs every 16" or 24", you might as well have just stick built off a foundation IMO.

Iv read about people who regretted cutting the drip rail off because rain water would go straight into the window. I'm trying to imagine how good it would look on a 4th gen econoline without pictures, but I don't think it would.

After manually prying out the body filler the previous owner used, some of the vertical drip edge is completely rusted away and gone. I know how to weld, but am reluctant to tear out the vans custom interior and remove ever bit of combustible material from my garage to prevent a home fire for a work van. But its not out of the question.

After some research, it sounds like epoxy is a better binder than polyester resin if I use fiberglass as long as you drill some holes for it to grab onto.
Iv watched a few video's of POR 15 Epoxy Putty and like its firm moldable consistency, ability to sand and reputation if I go that route.
Do you know if chopped fiberglass mixed into the west systems epoxy I have can be moldable and sandable like POR 15 Epoxy Putty? Or any idea what filler would since I already have a bunch?

Here's a video of half the damage. Thanks again Ram4ever.

http://vid640.photobucket.com/album...E-4CA6-85F0-BD5BB65AE224_zpscpzrhp1y.mp4
Posted By: Ram4ever Re: Softer, longer lasting Rain Gutter Seam Sealer? - November 28th 2016 1:56 am
Ouch; not good that it goes clear through! Sure glad you caught it now before it caused even more damage.

I tried doing some site searches for the shaved dripped rails, but I didn't come up with what I remembered. There was definitely a pictorial; I just don't remember whose build thread it was in. I have to think Superbeast would know who did it. It may even have been him. Why not drop him a PM and see if he can offer some guidance?


Body panel adhesive *is* a type of epoxy, and is designed specifically for use in automotive applications. The manufacturers recommend 36-50 grit sanding of the surfaces prior to application; no holes required. If you "flange" (recess the cut away edges of the metal by slightly more than the thickness of your replacement panel) you can make a perfectly flush sheet metal repair. I've even done it across curves and body lines.


I've been informed in no uncertain terms that chopped fiberglass is not desirable for the sort of use with epoxy which you're contemplating; it has a coating on its fibers which is incompatible with epoxy; it's only intended for styrene/poly resins.

Posted By: tuner4life Re: Softer, longer lasting Rain Gutter Seam Sealer? - November 28th 2016 2:11 pm
I'm going to be doing this soon as well prior to painting my van. Was leaning towards 3M 8307. Seems to be made specifically for things like this.

http://3mcollision.com/products/sealants/3m-self-leveling-seam-sealer-08307.html
Posted By: Ram4ever Re: Softer, longer lasting Rain Gutter Seam Sealer? - November 29th 2016 2:38 am
That 3m 8307 is the stuff I decided to go with. I have several cartridges waiting on warm weather or a heated garage, whichever comes first! smile

BTW, While I was looking for some pictures of my engine and transmission for Kylescore, I came across a picture of my drip rail when I had first applied the 3M Fast 'n Firm, prior to painting it. It looks really good... just didn't last.

[Linked Image]
Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - December 02nd 2016 3:32 am
Iv been digging out the seam sealer in the bad areas and have come to the realization that I'm screwed and all the time and money on the rebuild is costing me sleep. Almost tempted to call PO and remind him he's a shyster but I'm sure it would just get me more worked up.

So if I cut off the drip rail gutter after I rip out my custom interior.. Wont there be seam sealer between the roof metal and sidewall metal which will make it difficult not to contaminate the weld?

Thanks

Posted By: wrcsixeight Re: Softer, longer lasting Rain Gutter Seam Sealer? - December 02nd 2016 6:02 am
I've spent many hours cursing rust.

I use my fiberglass skills and Ospho and mechanical tooth and Epoxy now, and Aluminum C channel, for the improper fix, but removing my fiberglass top and welding it correctly is not going to happen.

So I just aim to slow it down, and mine is no show van.

Do not use fiberglass matt with epoxy, It works properly only with polyester ot Vinylester resins,

Use fiberglass cloth, or woven roving.

Epoxy however does not like Extreme heat or UV light. I paint my Epoxy white quickly and have no issues, but painted dark colors, I would not recommend.

http://www.fiberglasssource.com/sunshop/index.php?l=product_detail&p=88

Bare or even rusted steel prepped properly with Ospho, and this ^^ epoxy bonds incredibly well. Do not vary the 2:1 mixing ratio by volume, or 100:45 by weight.

Mixing epoxy improperly/incompletely WILL cause a never ending tool throwing curse fest. Cannot stress this enough. Do not vary the 2:1 ratio by volume or 100:45 by weight with this epoxy. I use a scale for much more precision as mixing cups are inaccurate.

This epoxy takes about 35 minutes at 70F to become puddy like, and shapable. Use ziploxk freezer bag plastic and a hard edge to mold it into shape after initally saturating the fiberglass when it was much thinner when first mixed.

https://www.systemthree.com/blogs/epoxy-files/tagged/the-epoxy-book

Before considering epoxy, read this, and do an experiment or two before committing to a large portion of the project. Epoxy hardeners are pretty evil. Protect skin and use distilled white Vinegar to clean tools, not acetone.



Posted By: Ram4ever Re: Softer, longer lasting Rain Gutter Seam Sealer? - December 02nd 2016 7:16 am
Yes, there is a thin bead of seam sealer recessed between the bottom of the drip rails and the sides.

The thing I'd have to point out about shaving drip rails on a Dodge is that this metal tends to do bizarre things when heated, so it might take you several days to weld all the way down one side slowly enough to prevent massive warpage.

I've been debating how best to even go about refreshing that recessed bead of sealer. I've been thinking of something like a slim jim to dig it out, or a piece of metal strapping from a big wood crate. Then it would require a non-leveling sealer to be injected back up inside the seam area.
Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - December 02nd 2016 3:31 pm
Originally Posted by wrcsixeight

I use my fiberglass skills and Ospho and mechanical tooth and Epoxy now, and Aluminum C channel, for the improper fix, but removing my fiberglass top and welding it correctly is not going to happen.

Thanks wrcsixeight.
What is mechanical tooth? You epoxy Aluminum C channel on missing or rusted out gutter sections?
Originally Posted by wrcsixeight

Do not use fiberglass matt with epoxy, It works properly only with polyester ot Vinylester resins,
Use fiberglass cloth, or woven roving.

What is the difference between fiberglass matt and fiberglass cloth regarding epoxy adhesion? Could I chop up fiberglass cloth, or woven roving to mix up a putty and completely fill the gutter above the rear door to prevent standing water?
Originally Posted by wrcsixeight

APEX Epoxy takes about 35 minutes at 70F to become puddy like, and shape-able. Use Ziploc freezer bag plastic and a hard edge to mold it into shape after initially saturating the fiberglass when it was much thinner when first mixed.

So do you wait 35 minutes before applying the epoxy? After watching a few videos of por15 epoxy putty, I was hoping I could mix up epoxy with chopped fiberglass to the same consistency ,but now told fiberglass cloth, or woven roving only. West Systems, System 3, Raka and FGCI seem to be the preferred epoxies on the net BTW.

Sorry for all the idiotic questions. I did call the PO this morning and called him out politely. It didn't help and now he's having a bad day also.

Originally Posted by Ram4ever
Metal tends to do bizarre things when heated, so it might take you several days to weld all the way down one side slowly enough to prevent massive warpage.

I've been debating how best to even go about refreshing that recessed bead of sealer. I've been thinking of something like a slim jim to dig it out, or a piece of metal strapping from a big wood crate. Then it would require a non-leveling sealer to be injected back up inside the seam area.


OK, forget shaving the gutters lol

The dodge roof to sidewall seam is different than the ford which is inside the gutter, not below so no way for me to get a tool in there except for the spots where the gutter has rusted away.

[Linked Image][Linked Image][Linked Image][Linked Image][Linked Image][Linked Image][Linked Image]
Posted By: wrcsixeight Re: Softer, longer lasting Rain Gutter Seam Sealer? - December 02nd 2016 6:48 pm
Mechanical tooth is just sanding scratches, small mountains and valleys which increase surface area and adhesion. Sharp sandpaper can scratch steel and is much better than dull sandpaper.

make sure to wipe with solvent before pushing contaminants into scratch valleys.

Epoxy makes its own heat. Do not mix and leave it in cup. Spread it out quickly to saturate cloth/roving.

Fiberglass Matt uses styrene to hold chopped strands into matrix. The styrenees in polyester and vinylester resins dissolves this and allows the matt to be worked/ shaped and fully saturated. Epoxy will not fully saturate it and the styrenes could inhibit the proper cure.

Do not chop up matt. Even chopping up cloth or roving will leave clumpy mess. Milled fiberglass can be added to mixed epoxy but it still gets a bit clumpy. Other thixotropic agents can be used. Read the epoxy book I linked.

I use a wet out table method. Clean cardboard Lay cloth or roving upon it and wet it out with properly mixed epoxy, then wet out properly prepped steel. Gloved fingers pull saturated figerglass from cardboard and lays patches in place. When epoxy starts thickening one lays ziplock freezer bag or similar thick plastic over area and can force out bubbles and shape it as the epoxy slowly gets thicker and thicker. How fast it gets thicker depends on temperature. Do not work it less than say 55f, or in direct sunlight. Keep it dry for 24+ hours after cure.

Plastic should be left on molded epoxy for at least 8 hours. It will peel off easily. If you molded it nicely, it might not even require any sanding, other than to get the paint to stick properly.

Do note this method is not tested in temperature extremes. Epoxy has Much higher adhesion and is much more flexible than polyester resins, and will boind to properly prepped, etched, mechanical toothed steel.

I do have Aluminum C channel replacing the rotted roof gutter over side and front doors. Side doors have Epoxy fiberglass and aluminum bonding to prepped steel, both gray and black from the Ospho. Shows no signs of cracking
Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - December 03rd 2016 6:11 pm
Thanks again wrcsixeight.

I cut the rotted vertical section of the gutter above my rear doors off and do not plan on rebuilding fords water trap that caused the rust in the first place. I want to epoxy a cap over the two edges with a steel U channel I hope to find. It would need to be 1/4" to 3/8" wide inside and about 3/4" deep and 20-16 ga.
[Linked Image]
Originally Posted by wrcsixeight

Fiberglass Matt uses styrene to hold chopped strands into matrix. The styrenees in polyester and vinylester resins dissolves this and allows the matt to be worked/ shaped and fully saturated. Epoxy will not fully saturate it and the styrenes could inhibit the proper cure.

Do not chop up matt. Even chopping up cloth or roving will leave clumpy mess. Milled fiberglass can be added to mixed epoxy but it still gets a bit clumpy. Other thixotropic agents can be used. Read the epoxy book I linked.


Will mixing milled fiberglass and epoxy make it into the consistency of Bondo Glass?
[Linked Image]
Or should I lay up some fiberglass cloth and epoxy on a flat plastic surface and allow it to cure. Then cut it to the shape I need to rebuild the smaller spots along the gutter sides?

Thanks again.
[Linked Image][Linked Image]

Posted By: wrcsixeight Re: Softer, longer lasting Rain Gutter Seam Sealer? - December 03rd 2016 9:20 pm
Milled glass fibers do thicken epoxy, but it does not seem to make it into a nice smoothable paste like Bondo, and it is Much much harder to sand. BOndo sands like balsa wood compared to epoxy.

I collect the Cedar dust from my belt sander 120 grit or finer) and mix that into properly mixed epoxy when i want to apply a paste to a surface. I can and do add milled glass fibers in with the wood dust/flour to increase strength if it is not getting covered in fiberglass cloth. But milled glas fibers are too damaging to ones lungs. Always use lung protection when cutting fiberglass.

Other thickening agents can be added to epoxy, like phenolic microballoons, which will make it into a nice spreadable paste which sands easily.

I have layered fiberlgass cloth or tape on Waxed glass to make a perfectly flat piece which I can later cut and shape and bond.

Secondary bonding with epoxy can be on the chemical level, if subsequent layers are added within a certain period of time, which depends on the speed of the epoxy and the temperature at which it is curing. If moisture has condensed on the epoxy, or the epoxy is not claimed to be 'blush free', an Amine blush forms on the surface which inhibits this secondary bond. This Amine blush will feel waxy and will likely be whitish in color.

It is water soluble (use gloves and a scotch brite pad to remove) and secondary bonding should be good. But sanding all shiny surfaces with sharp new 120 grit sandpaper will ensure the best possible mechanical bond and hopefully chemical bond too if withing that time window.

One can make molds, or use an existing C channel and wax the interior with car wax, preferably mold release wax, and make any shape they want, but epoxy bonds so strongly that removal from waxed mold can prove to be difficult, especially if on a curved interior surface. The epoxy I linked will not bond to most plastics, but I'd hit them with a wax before anyway.

Proper surface preparation cannot be stressed strongly enough for proper bonding of epoxy to steel or aluminum, or epoxy to epoxy when the possibility of amine blush exists, and the Amine blush even forms on 'blush free' epoxies when exposed to moisture during the cure.

Protect surfaces below gutter from epoxy drips as if it cures on paint, it will remove the paint when you try and remove it.

The epoxy I linked is super clear 'water white' but yellows fairly quickly in UV light, so drips are not apparent until later, and working with a cardboard 'wet out table' and lifting pre saturated pieces of fiberglass into place with gloved fingers, is messy work.







Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - December 05th 2016 2:53 am
Thanks again.

My plan now is to apply packaging Tape over a good section of my gutter and place epoxy wetted fiberglass cloth over the taped gutter and allow it to cure to make the shape. Then I can cut and fit it into the rusted out sections.

My only concern now is what you said about "subsequent layers added within a certain period of time"

I work slowly, especially doing something the first time. If I wait a few days after the epoxy has cured, will the next layer of epoxy and fiberglass cloth not adhere well?
Posted By: wrcsixeight Re: Softer, longer lasting Rain Gutter Seam Sealer? - December 05th 2016 7:39 am
I hear you on the working slow.

The chemical bonding of epoxy on epoxy layers is most desirable, but epoxy is such a strong adhesive, that sanding alone with 120 grit will ensure a very good secondary bond, it is just the chemical bond is more apt to act like there are no layers.

Do remove any possible amine blush with the scotch brite pad and water, and dry thoroughly, before sanding with 120 grit for best possible mechanical tooth bond.

Do keep it dry and free from condensation forming on it overnight when curing.

it is not something you want to do right before temperatures fall to below 50 overnight. that apex epoxy I think says not to ask it to cure under 55f. It will eventually get hard when it does get later get warmer, but it will inhibit progress and clog sandpaper until enough time passes and this might be another 12 hours once it warms back above 55f, SO best to give it 3 to 4 hours to get 90% cured in 65f+ temps. That last 10 % takes 3 days or so, and some level of chemical bond can occur within this last 10% too, but I do not rely on it alone, I always sand, unless the first layer is still tacky enough to leave a fingerprint.
Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - December 23rd 2016 12:37 am
Originally Posted by Ram4ever

I've had really great results with the 3M 2-part body panel adhesive, and pretty much swear by it, with the caveat that if your local jobber doesn't move much volume you'd better call 3M from the parking lot prior to leaving with it to verify that it hasn't expired!

So, I do give a thumbs up to the 2-part products, as long as the date codes are provably within the products intended expiration dates.


Hey guys.. I don't know about you, but Iv been hibernating lately with the temperature below 40 degrees in my garage. I have allot of the metal ready for repairs, but don't want to use epoxy even with my electric heater.

I want to use the 3M 8116 you recommended when replacing sheet metal over the rear doors.

Do you have the 3M phone # you called to check the codes or date?

And is the 3M 8116 sandable and paintable Ram4ever?

Thanks! And happy holidays!
Posted By: Ram4ever Re: Softer, longer lasting Rain Gutter Seam Sealer? - December 23rd 2016 7:06 am
Rebar, the body panel adhesive is fully sandable and paintable as soon as it's cured, which is within several hours depending on which type/brand you obtain. Generally, you treat it like it isn't even there; sand it smooth like the surrounding metal, then go ahead and paint right over it with your epoxy primer and away you go.

A big benefit of using panel adhesive is that by its very nature as an epoxy, it's a seam sealant, so you don't need to be concerned with porosity or cracks like you might find hidden in a line of weld coins as you grind it down. And getting at the hidden backside of a seam to try to rust proof it isn't so much of a big deal; the adhesive seals the entire surface it's in contact with plus a bit more where it squeezes out. And since you're not welding, you're not left with a large heat affected zone devoid of paint surrounding your seam, which would just be itching to soak up some moisture and start rusting from the inside out!

Panel adhesive won't absorb moisture or change dimensions like some poly sealers will, and it's not at all chalky when cured, so it's a pleasure to work with. When uncured it does smell rather acrid though; some ventilation is highly desirable. Mid winter with closed garage doors and a heater isn't the very best of conditions for applying this stuff in my book. If I were to try it I'd use a chemical rated respirator mask and gloves.

The trick to using it properly is to understand that it contains tiny glass beads as spacers, so that when you clamp it down, the excess adhesive is squeezed out of the seam to the thickness of the glass beads, leaving you with the optimal bond line thickness for maximum shear strength. You simply can't over clamp it and be left with insufficient adhesive. It's no exaggeration to say that typically the metal will fail prior to the adhesive.

As far as the date checking, I just call 3M's Automotive Aftermarket Division support line, and ask for technical support on whichever product I'm calling about. The number is 877-666-2277, (877 MMM CARS) which is included in the information packet which comes with each package. They're happy to answer any questions you may have, and they can offer some great advice if you find yourself wondering about the optimal way to apply the product, or whether there may be any chemical compatibility issues.
Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - April 16th 2017 1:28 am
Hey guys. I hope everyone had a great winter..

I'm now considering everything Iv learned here , and on the net for this project.. I need the van on the road and my garage back.

I have a few questions and a interesting product to point out.

I found a new west systems epoxy called Six10 thickened epoxy.. Iv never seen a epoxy fill gaps and not run and sag from overhead and side walls like this Six10 stuff. I found it when reading a article about "west systems autobody repair" and figure it could come in real handy for the vertical repairs I'm doing. So I tried to figure out what fillers Six10 uses,, but found this.

"Six10 adhesive gets it's gel character from a chemical interaction meaning, it is not simply thickened. This chemical interaction gives Six10 a property known as shear thinning. When a shear load in applied to the material the viscosity lowers and when the shear load is removed it returns to a non-sag gel. the act of dispensing it is the shear load needed".

So it looks like Six10 cant be simply copied by adding micro balloons and colloidal silica to a good epoxy unfortunately?

But my main question is this..

Can anyone explain the best way to use the Ospho on clean wire wheeled steel which might still have heavy pitting? Should I use wax and grease remover before Ospho? Does the Ospho need to be removed , washed off , before applying epoxy on the roughed steel? I know whichever rust converter or cleaner I use before the epoxy will remain between the roof seam as its to narrow to get a brush or tool between is why I'm concerned.


Thanks!


Posted By: Matman Re: Softer, longer lasting Rain Gutter Seam Sealer? - May 06th 2017 11:07 am
What a great thread, as I mentioned earlier I decided to remove all the old gutter sealer. mainly because as I am in the process of a full repaint and the existing sealer just looked too crappy,Thanks.Now I have a clearer idea of what to use.
BTW, to add some additional detail to the thread, I found a picture I'd taken of what was left of the single stage 3M Fast 'n Firm seam sealer when it failed. It failed quickly and miserably, even with the coating on top of it. Peeled up like cracked mud despite all the surface prep. I sure won't go down that rabbit hole again!!

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Just imagine all the water and debris that got under that... My neighbor has black walnut trees, which are what made all the black speckles. Makes my skin crawl to think of it! Glad I discovered the failure when I did.

It's 2-part sealers for me from now on!
Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - May 26th 2017 12:37 am
Wow that's terrible.. Yes two part, or maybe epoxy? It sure is cheaper..

Iv been getting busy with the warmer weather and layed up the rear gutter in a mold and got it fitted..

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I feel comfortable now with what Iv learned about epoxy thanks to wrcsixeight especially. But I'm still unsure how to prep pitted steel for epoxy the best. West Systems and the boat community say wipe with acetone.. But if you study clean and prep products, the automotive industry discourages acetone and lacquer thinner because they still contain small amounts of contaminants.. Lacquer thinner is also said to evaporate to quickly and not float contaminants long enough to wipe away etc.

Id like to neutralize the rust with ospho, but I cant wash it away afterwards (important step) from between the roof and side wall "crack" and didn't want to risk getting water in the cracks where it might take days to evaporate.

Any tips or information about residual ospho? Or a good clean and prep product Iv over looked? Many automotive products require a two part prep.

I read the same thing about acetone mieral spirits and laquer thinner. They sell some sort of alpha and Omage degreaser for ultimate bonding to metal, i forget what it is called but I did not bother acquiring it.

Ospho remnants, well in my experience it only has a white powder if the surface had no contaminants on it, and this can be brushed off with a green scrubbie pad. If it is still green and gummy then wipe up the residue lightly with more ospho on a paper towel until clean and hit the steel with a hair dryer until it is obviously dry, and it will be obvious.

I've gotten short of time and used denatured alcohol too to wipe the steel of Ospho pre epoxy, but I have also scrubbed the steel with wet/dry 60 grit folded over a piece of sponge for maximum mechanical tooth.

Be very precise when mixing the Epoxy. the bond strength and cure strength are depependent on a precise resing to hardener ratio, it is not like polyester resin, usually called fiberglass resin, to which one adds X amount of catalyst.

I hated west systems for its 5 to 1 ratio which made it all too easy to mess up.

I now use a small digital scale and measure my batches of epoxy to the 0.01 th of a gram.

When mixing the epoxy, make sure the mixing stick can get into the corners of the mixing cup. Mix on a level surface under a lot of light and mix it until you can see no swirlies. Wipe all 5 sides of the mixing stick more than once and remix that into the mixing cup. Do not spill any epoxy down the sides of the cup when mixing, If you do this can throw off the ratio of hardneer to resin, especially if in the early stages of mixing.

Keep the hardener off your skin. The sanding dust is toxic for about 3 days, then inert.

If one mixes epoxy incorrectly it might still harden, but not cure to its full strength or hardness or elasticity or bond as strong as it otherwise would. If one does nto fully mix the resin and hardener there will be parts which harden and others which stay soft.

i canlt stress enough how important it is to mix in the proper ratio, and mix it thoroughly I find a strong hedlamp aimed ito the mixing cup reveales 'swirlies' I could not see with naked eye, and those swirlies indicete more mixing is needed. I generally spend no less than 3 minutes mixing the epoxy, scraping the mixing stick on the side of the cup, spilling none on the outside, then scraping the side of the cup and mixing it again, over and over.

If it does go wrong, fixing the mistake is 2x as much work as you have already done, and toxic.

One method I came across since my last posting in this thread is the use of a clear plastic baggie on top of the
still wet and moldable epoxy. Much better than waxpaper. i would use various tools to push out any bubbles and shape the epoxy/ fiberglass to whatever shape I wanted. I've been using the large ziplock freezer baggies but some uncreased plastic would be better. The epoxy will not bond to the plastic, just let it fully cure and peel it off and one can reduce the level of sanding by a huge amount, or possibly eliminate it.

I have fixed rail dings on my surfboards using this method and not have had to sand at all once I remove the plastic. I was using a squeegee to push out all extra epoxy on top of the masking tape I confined the ding with, but, then razoring just inside the tape and removing tape leaving plastic in place while epoxy cures, but my last job I used no tape, just pushed the epoxy to the edge of the plastic and soaked it up with a napkin. It came out great and glossy and ready to go.

The roof gutter can fight, the plastic trick can really be useful on stubborn areas. Keep some around ready to go. DO not work in direct sun, and do not leave the properly mixed epoxy in the cup for very long as it will create its own heat and start gelling fast. Spread it thin in a tray to increase working time while applying it.

Keep moisture/humidity off the epoxy while it cures which might take 72 hours. If it gets wet then it might turn white and then this must be sanded off before painting, or layering more epoxy in another batch, but west system epoxy will require this anyway.

I can;t stress the proper ratios enough, you get about a 3% margin for error, and mix it in the cup wisely, and for about 2x as long as you think it requires to be fully mixed, then perhaps a bit more. From there the clock is ticking.
Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - May 26th 2017 11:36 am
Again, thanks wrcsixeight.

Iv been mixing/measuring epoxy (MarinEpoxy from boat builders central) on my digital scale which is very consistent and weighs to the tenths of a gram.. Its great especially for small batch's and clean up is non existent with ziploc bowls and West Systems plastic stir sticks which fit the round corners of the bowls. The ratio is 100 parts resin for 43 parts hardener by weight. It is still 100 parts to 50 by volume but the hardener is heavier. So I multiply how much resin I just poured by 1.43 and add hardener to that amount. Great tip!

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There's another thing other than metal prep I still don't feel comfortable with.. Filler recipes.

I'm using Milled glass fiber, silica and microballoons..
Iv read a good rule of thumb is about 1/2 tsp of Milled fiberglass per ounce of epoxy. And have read no more than 1/3 as much cabosil as filler, whether it is flock or microballoons.. so I will try 1/3 cabosil and 2/3 microballons... I guess..

But I'm winging it here and having to wait a few days to know if my testing batch was a success, and how to test and grade the success and how to further tweek the recipe is beyond me.. I need a filler recipe book.
I am not really so upto date on the fillers. My need for them is limited. I always had issues with cab o sil turning into a cottage cheese consistency and started avoiding its use

I use milled fibers and wood flour. The milled fibers go in the mixed epoxy first and is kindof difficult to get the lumps out. My fibers must be milled from volan cloth as there is a greenish tint.
The wood flour I use is just Western RedCedar sanding dust I collected from my belt sander, I add that second until it is just a bit thinner than I want, then spread it thin on a tray to extend working time, and hopefully it is the right thickness when I apply it or clamp it. The amount of wood flour depends on how thick I want it. i just add more and more until it is like runny peanut butter than slow down the amounts I add. It takes a lot more dust than I expect, usually.

My epoxies range from 100:45 to 100:43 by weight, and a even 2:1 volume ratio. I pour the resin in the cup, multiply that weight by 0.45, hit the tare button ,then pour the hardener to the 0.01 of a gram. My batches can be as small as 7.5Ml so I dig this level of precision that one cannot really achieve when pouring by volume.

3M offers several different cleaners which are specific to cleaning surface contaminants due to old adhesives, prior to new adhesive or paint application. A particularly convenient one is their 3M General Purpose Adhesive Cleaner 15oz. Aerosol #08987, which is inexpensive and simple to use, as it comes as a conventional spray can,, and it addresses your one concern by being a less volatile material, so it deals handily with lifting embedded contaminants out of deep pores and surface texture after abrasives have been used. It is also available in quarts, as 3M 8984 General Purpose Adhesive Cleaner - #08984.

Another strong possibility might be 3M Prep Solvent-70, Gallon, #08983.
Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - May 27th 2017 11:36 am
I would pick the 3M Prep Solvent-70 as its intended use is cleaning "prior to coating"

I keep reading "Wax and grease removers".. But I also keep reading many pro's say you should use two metal preps. The first a solvent based cleaner.. And the second a water based cleaner like the 3M Prep Solvent-70..

As far as fillers.. I have high hopes that the silica will make the epoxy thixotropic, or defy gravity. MGF is for strength and microballoons ease sanding.. But its the thixotropic properties of silica which I hope helps keep the epoxy from running down hill.

I wish I knew what fillers bondo glass and the like have mixed in them.
https://www.systemthree.com/blogs/epoxy-files/83508804-section-vii-c-modifying-epoxy-with-fillers

Mechanical tooth/ sanding scratches with sharp new sandpaper will help the bond greatly.

Before mixing anything into the epoxy to thicken it, paint some epoxy on the bare prepped metal. With bare wood this is very important as the wood can suck the epoxy out of the thickener and the bond line will fail, with metal one is just ensuring the valleys are filled with epoxy, not air.

It is important not to push contaminants into the valleys when sanding/ scratching for mechanical tooth.

I am not so impressed with the bond strength of regular bondo. it does sand nicely though. Sometimes epoxy can be a butch to sand. The plastic trick can greatly diminish the amount of sanding required.

Experiment before committing to any one method.

I am not always so fond of fillers to thicken. Sometimes I will mix a batch, wet the surfaces to be mated/filled/bridged then wait for the epoxy to thicken in the cup until it no longer is runny, then apply it with some sort of tool, possibly use the plastic over it and mold it as it thickens further.

Posted By: rebar Re: Softer, longer lasting Rain Gutter Seam Sealer? - June 14th 2017 11:28 pm
Originally Posted by wrcsixeight

I am not always so fond of fillers to thicken. Sometimes I will mix a batch, wet the surfaces to be mated/filled/bridged then wait for the epoxy to thicken in the cup until it no longer is runny, then apply it with some sort of tool, possibly use the plastic over it and mold it as it thickens further.


Iv found that epoxy in this thickened, or beginning to set up state, is super sticky and will not release or flow off of a tool cleanly. So I made a mold of the side gutter and will lay up up a replacement part first. Epoxy it in place on the van and then apply more layers behind to strengthen like I did on the back gutter.

My problem now, is I cant get 2" packing tape to lay smoothly in this concave mold. Mainly the drip edge. I had more luck with the wooden mold for the back gutter because the mold was larger, wooden, and I routered a 1/4" drip edge. The side gutter mold's drip edge is 3/16" and each time I try to apply packing tape, I get air bubbles and folds because the packing tape sticks so well to the epoxy mold. Maybe Im fighting it because this side gutter mold is so small, and my tape is 2" wide? Can I use 1/2" cellophane tape instead and meet two pieces inside the drip edge?

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The back gutter is looking great! I have some sanding and a few air bubbles to fill.. But I bet at first glance you wouldnt know its been repaired when I'm finished..

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If I wanted to post cure these repairs, how can I localize heating up to 130 degrees? I'm a bit worried about it softening in the sun even with white paint because when I washed my epoxy mold in hot running water, it became soft.

Thanks!
Post curing at higher strengthens the epoxy, but this is not really a requirement in this application in my opinion.

I would fear it might compromise the bond to the steel.

Applying the 'thickened by time' epoxy certainly is very time sensitive.

I'd use freezer bags for molding, not cellophane tape. The adhesves in the tape can remain behind and cause secondary bonding issues.

Sometimes bubbles or gaps are unavoidable. Once one decides to leave them, it is best to try and drill a hole and inject some more into the void somehow. Sometimes this requires a small drill hole top and bottom.

If the weave of the cloth does not want to bend as desired, sometimes pullmany individual strands from the cloth and lay they all in the same direction like an unbraided rope. I use a low of woven roving like this, just pulling larger individual strands. These larger individual strands can be difficult to wet out completely. helps to bend and flatten the roving over a smooth radius I will tape one end of the roving, and use a corner of the cardboard to lay the roving in and allow the epoxy time to saturate, then lift with one hand and squeeze out the extra resin.

Posted By: BushcraftVan Re: Softer, longer lasting Rain Gutter Seam Sealer? - January 18th 2019 8:49 pm
Hi guys, I'm new and a bit late to the conversation, but I used Dicor Self Leveling Lap Sealant RV Roof Caulk to seal the rain channel seam on the top of my 77' Chevy G20 Van. All the hardcore van living guys swear by it. It really settles into the all the cracks and seams and is also paintable. I bought mine from a local RV place, but it is also available online. I used 3 tubes on my van roof but it is best to buy 4 because you don't want to run out in the middle of the job. Hope this helps.....
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