Glidden Gripper vs PPG gripper

[Postal_Dave]

People do dilute gripper for the making of Poor Man's Fiberglass. After adhering the canvas to the foam, people take Gripper or TBII and dilute it to a 50/50 mix and coat the canvas. The idea is to get the solids in the primer, or glue, embedded into the strands of the canvas. This is supposed to prevent the canvas from rotting over time. They put a coat of 50/50 on the canvas, it takes several days to dry completely, (some people use several coats and I've even seen some people sand the canvas between coats to get the canvas to soak up more of the 50/50 mixture), then they use full strength primer over that, then good exterior paint.

Remember, we are not experts and we are still trying to find the very best, and cheapest, way to make a homemade camper. We have yet to come to a consensus for a standard way to make PMF. The closest I've come up with is the 9 steps I use to adhere the canvas to the foam. After that, talk to GPW. He's the one with the most experience with PMF.
To tell the truth, for me, the experiments are half of the fun.

[John61CT]

I was not saying it isn't done.

Just that I wouldn't do it.

[Postal_Dave]

Someone asked about the Valspar Bonding Primer. I didn't do any tests on it, but I did pick up a MSDS on it from Lowe's.
The ingredients listed are...
Titanium Dioxide % by weight >= 10 - <=25
Kaolin % by weight <=5

Someone tell us how that compares to Glidden Gripper and PPG Gripper please.

[John61CT]

Can't go by that, effectiveness is as effectiveness does.

Testing. . .

[GPW]

Guys, As a professional Artist for 50 years now , we’ve prepped and painted a lot of Canvas over the years … disclaimer: We kept them inside under stable conditions … the remaining ones not sold off are still like new !!! We’ve always followed the idea of a stretched canvas needing a “sizing” coat to “seal" the individual fibers to prevent rotting or being affected by the top coats of paint .( My artist Oil paints tends to rot unprotected canvas over many years, why we size and prime ... ) Traditionally “Rabbit skin glue “ ( hide glue ) has been used for that , but with the advent of Acrylic paints , the Acrylic primer will perform the same function … The trick is Diluting the paint so it can seep inside and encapsulate the fibers. We’ve been doing it for years , just as we’d dilute an enamel, alkyd or lacquer… The trick is to only dilute it enough for the job you’re doing ...

Paint is basically just Three materials … The Pigment (coloring) , the Glue to hold the pigment together ( binder ) and the solvent to thin it and clean up ..Other ingredients may be added for various reasons . ( fungicide , UV resistance , etc. )
Thee real story with thinned glue ( or paint) is that , sure it’s going to lose Bonding strength because the glue molecules are diluted , not as if the molecules lose any strength , but with the added solvent , they are further apart ( Capisce ? )
Primer is mostly Paint with lots of Titanium Dioxide ( Pigment ) to make it thick and better “covering” ,and a good smoother surface for the final paint colors . That thickness prevents the protective sizing primer from really soaking into the fibers , so we thin it ( solvent ) … Naturally once "sized“ The canvas can be conventionally primed with undiluted Thick primer . So thin away as to your needs … IT’s OK !!!

Glidden vs PPG ??? … That remains to be tested over Time , but I’m sure both are good as Primers and attaching canvas … For other properties like sticking to metal or other plastics , we know that’s gotta’ be tested too. Like Dave said ^ “ To tell the truth, for me, the experiments are half of the fun. “ …

[zzzizxz]

I feel confident I found my replacement.

I tried painting a coat of the Zinsser Bondz on a piece of aluminum today.

It was more similar to the original Glidden than the new PPG. It was just as thick as both, but it had more of a chemical scent to it, like Glidden.

After letting it dry/cure in the sun for about 20 minutes, I tried scratching it off the aluminum. While I was able to get a little of it to come off with my fingernail, it took some real work before it would scratch off. Even when I was able to scratch it off with my fingernail, I could only get it to come off in small patches, and not reliably.

When I tried with a screwdriver, it was just like the Glidden. I could get it off, but it was scoring the aluminum to do so.

I haven't tried it with any other medium, but the adhesive properties are similar enough, and the "Bondz" is thick enough, that I really think it will be a direct replacement. For me anyway.

[Hamilton Felix]

Great! Looks like PPG just made some Zinsser customers.

[John61CT]

Every data point adds to the community knowledge base.

But reports from dozens of builders

encapsulating actual canvas + foam,

followed by long term torture testing in real-world conditions

will IMO be needed before a new king is truly crowned.

Interim testing by each of us to determine what's worth using **for ourselves** is of course an essential critical step in that direction.

[Postal_Dave]

At the risk of being beat up, I'm going to throw out a thought.
I looked at the MSDS for the Zinsser Bondz.
Chemical Name: Titanium Dioxide (White pigment), Talc (Adhesion agent), Dipropylene Glycol MonobutylEther (Solvent), Aliphatic Petroleum Distillates (Solvent).
Nothing in it is UV resistant and I don't know how well it would work as a filler for the canvas weave to prevent rot.

In Glidden Gripper, the chemical that gave weather resistance and UV resistance was called Styrene Acrylic Copolymer and it was 10-20% by volume. This chemical is supposed to also be in automotive paints.
Glidden Gripper also had limestone and quartz for fillers, that may be why it keeps the canvas from rotting as well as it does.

Instead of using one, all purpose primer to make Poor Man's Fiberglass, it may be best to use a layering system.
The Bondz could be the adhesion for the canvas to the foam. Possibly diluted TBII to fill the weave of the canvas to prevent rot. (Diluted TBII has been used successfully before for that.) Then another primer or paint with a high UV and weather resistance property as a top coat.

[WoodSmith]

I'm no rocket surgeon, but the titanium dioxide itself should be UV protective. It is a key ingredient of many of the less carcinogenic sunscreens. Once the primer is covered by a top coat, there should be very little UV getting to the primer anyway.

I found a home depot in Danville VA that still has glidden gripper and have purchased 3 gallons, so I should be set for my pending build. I think using the product that performs the primary function best is the right choice - in this case the primary function is adhesion of canvas to foam. The above testing seems to indicate that Zinnnser has an edge over the PPG gripper.

In the end, more testing will need to be done and compiled by the community until a new SOP for canvas to foam gold standard is decided upon.

Sent from my SM-G892A using Tapatalk

[John61CT]

Instead of using one, all purpose primer to make Poor Man's Fiberglass, it may be best to use a layering system.
The Bondz could be the adhesion for the canvas to the foam. Possibly diluted TBII to fill the weave of the canvas to prevent rot. (Diluted TBII has been used successfully before for that.) Then another primer or paint with a high UV and weather resistance property as a top coat.

Cost issues, complexity, possible compatibility problems that only show up years later.

To me the foundational ethos of PMF is

low-tech simplicity, small number of low cost commonly available materials.


I am only concerned about weave-filling from the structural / waterproofing POV.

If a smooth finish is desired for **cosmetic** reasons, that along with the outermost paint is to me a separate issue, lots of filler approaches including acrylic gesso with GG.

But for me the only issue here is structural and waterproofing, and

I want **one** adhesive-sealant that waterproofs, encapsulates and bonds the canvas to the foam.

[Zzyzx]

[quote="zzzizxz"
I tried painting a coat of the Zinsser Bondz on a piece of aluminum today.
[/quote]

Like many other things, surface preparation is key when painting/bonding to aluminum. Aluminum quickly forms a thin aluminum oxide layer under normal atmosphere. This thin layer protects the underlying aluminum from further corrosion. Paint or adhesive may bond well to this oxide layer, but the oxide layer is not well bonded to the aluminum underneath. Use a stainless steel or brass wire brush to remove the oxide layer, wipe down thoroughly, and then paint/glue immediately. Mark your wire brush for ALUMINUM only. Do NOT use it for any other metals. Cross contamination can cause corrosion issues. Remember, the oxide layer forms quickly so make sure you have everything together to paint/glue it immediately after brushing.

[GPW]

Thanks ZZ !!!

[MatBirch]

Instead of using one, all purpose primer to make Poor Man's Fiberglass, it may be best to use a layering system.
The Bondz could be the adhesion for the canvas to the foam. Possibly diluted TBII to fill the weave of the canvas to prevent rot. (Diluted TBII has been used successfully before for that.) Then another primer or paint with a high UV and weather resistance property as a top coat.

Cost issues, complexity, possible compatibility problems that only show up years later.

To me the foundational ethos of PMF is

low-tech simplicity, small number of low cost commonly available materials.


I am only concerned about weave-filling from the structural / waterproofing POV.

If a smooth finish is desired for **cosmetic** reasons, that along with the outermost paint is to me a separate issue, lots of filler approaches including acrylic gesso with GG.

But for me the only issue here is structural and waterproofing, and

I want **one** adhesive-sealant that waterproofs, encapsulates and bonds the canvas to the foam.

At the risk of sounding condescending...
we are talking about primer here, correct? They are inherently designed to be topcoated, not used as a one step process.
If directions are followed, compatibility and bonding issues should never be a concern. A quality topcoat paint should provide far better waterproofing, UV resistance, abrasion resistance, etc than any primer ever could.

[John61CT]

Sorry if I wasn't clear.

Yes of course there is an outermost skin.

I was making the case against unnecessary complexity under that, KISS

GG has been both the structural adhesive for the canvas, and IMO the primary waterproofer. As stated above

Gripper is supposed to do the heavy lifting for waterproofing just fine.

The only jobs left for outermost coatings are iirc

further smooth the texture
protect against UV (very important)
be a cool color

For me the key criteria would be maximum long-term compatibility with the primer / adhesive / sealant used, e.g. the Gripper