Polycrylic to the test.

[leblanda]

Hi,

I started my polycrylic test.
I did a test some piece of XPS foam with 6 oz cloth and polycrylic.

I did two pieces test.
One with puncture and the other without the puncture.
I put 2 layer of polycrylic. One that I did sand in between layer.

One question.
What is next?
What is the delamination test compare to PMF?

If I try to peel the cloth it is well stick to the foam but it does not destroy the foam.
How I can say that it is glued enough to the foam?

Thanks

 

[Tony Latham]

I put 2 layer of polycrylic.

As in Miniwax Polycrylic?

 

[leblanda]

As in Miniwax Polycrylic?

Yes that is miniwax polycrylic.

 

[Pmullen503]

6 Oz. fiberglass cloth?

I suppose you could do a peel test but that's not really the point with foamie construction. What you really care about is tensile strength. The bond to the foam can never be stronger than the foam itself and doesn't have to be. There is so much surface area in the direction that matters, even a weak bond is adequate.

The comparison I'd be interested in is cost/ease of use and tear and puncture resistance.

 

[Tony Latham]

Yes that is miniwax polycrylic.

I think for the same price, you could do the real deal: Epoxy/fiberglass.

 

[leblanda]

I think for the same price, you could do the real deal: Epoxy/fiberglass.

I do not want to mess with resin and warmfull stuff.

 

[leblanda]

6 Oz. fiberglass cloth?

I suppose you could do a peel test but that's not really the point with foamie construction. What you really care about is tensile strength. The bond to the foam can never be stronger than the foam itself and doesn't have to be. There is so much surface area in the direction that matters, even a weak bond is adequate.

The comparison I'd be interested in is cost/ease of use and tear and puncture resistance.

I try to find Titebond locally but not able. i would like to test copare to with canvas and glue.
Any alternative glue?

 

[Pmullen503]

Just about any waterbased glue will work, even latex primer. Again, the bond doesn't have to be great, there is so much area in the direction that matters (parallel to the surface) and even a perfect bond will just peel off the foam just below the surface.

 

[leblanda]

Ok I tried these combo:

1- Foam + Polycrylyc + 6oz fibercloth better than valspar
2- Foam + Valspar primer + 6oz fibercloth good result
3- wood + Valspar primer + drop cloth good result
4- wood + lepage carpenter wood glue + drop cloth very good result
5- Foam + Valspar primer + drop cloth drying stage
6-Foam + Polycrylyc + drop cloth drying stage

"With the foam and the drop cloth, the corners seem to curl up when drying with the Polycrylic and the Valspar primer."
I will see tomorrow.

As info the valspar I took is

"Valspar stain-blocking bonding primer"

stay tuned

Dan

 

[Tony Latham]

"1- Foam + Polycrylyc + 6oz fibercloth better than valspar"

Why not the real deal?

No experimentation needed.

Tony

 

[Pmullen503]

Ok I tried these combo:

1- Foam + Polycrylyc + 6oz fibercloth better than valspar
2- Foam + Valspar primer + 6oz fibercloth good result
3- wood + Valspar primer + drop cloth good result
4- wood + lepage carpenter wood glue + drop cloth very good result
5- Foam + Valspar primer + drop cloth drying stage
6-Foam + Polycrylyc + drop cloth drying stage

"With the foam and the drop cloth, the corners seem to curl up when drying with the Polycrylic and the Valspar primer."
I will see tomorrow.

As info the valspar I took is

"Valspar stain-blocking bonding primer"

stay tuned

Dan

Canvas drop cloth will shrink a bit with waterbased adhesives. That's not a bad thing if you plan for it. The tension on the cloth as it dries adds stiffness to the foam.

On a trailer, you wrap the edges around a corner and pay attention to it while it's drying to make sure the edges stay down.

 

[leblanda]

"1- Foam + Polycrylyc + 6oz fibercloth better than valspar"

Why not the real deal?

No experimentation needed.

Tony

As mentionned, i do not want to mess with epoxy warmfull stuff.
I saw that you are not hearring respirator when applying the epoxy!?
Is it safe?

Regards

 

[Tony Latham]

As mentionned, i do not want to mess with epoxy warmfull stuff.
I saw that you are not hearring respirator when applying the epoxy!?
Is it safe?

Ooops. I forgot about your previous response.

Epoxy, unlike polyester resin, is relatively benign. You just need to keep it off your skin.

Tony

 

[KCStudly]

It's the shear strength along the glue joint that matters. It will peel up easily, as others have said, but it should have a very faint trace of foam "fuzz" all along the glue where you peel it up.

Well ventilated, some people aren't sensitive to epoxy. I choose to always wear a respirator, latex gloves and eye protection. Never sand even a little bit w/o the respirator. Suppose you could say the same thing for wood dust,