Thread: Some basic glue tests

Sorry Micy is that Titebond poly?
I think if you have a good firm joint then you could get by with poly but its not going to ad much strength to the joint. Mind you when I had to knock that joint apart (radial movement) it took a few pretty good whacks to break the joint but it did fall short of taking wood like the others. And this is only one brand (Sika), I have used Vise brand previously and had the similar results from similar tests at the time. They were on Blackbutt.

Originally Posted by Claw Hama

Sorry Micy is that Titebond poly?
I think if you have a good firm joint then you could get by with poly but its not going to ad much strength to the joint. Mind you when I had to knock that joint apart (radial movement) it took a few pretty good whacks to break the joint but it did fall short of taking wood like the others. And this is only one brand (Sika), I have used Vise brand previously and had the similar results from similar tests at the time. They were on Blackbutt.

Sorry Claw, yes poly. Have edited my post. Titebond PVA's I like.

Cheers
Michael

My only gripe with Titebond has been with TB III which I found very runny. I like my glue to be a little thicker but then its vey thin and doesn't take up much space in a neat joint.

David showed me some of those photos the other day and said a local woodworker had done the test.

Now I know where they came from.

Great stuff.

Yep, his Woodloc glue at half the price of the others stuck realy well so I took him up some photos. Most people like me would wonder if this home brand glue was any good.
He is very reasonable with all his hardware prices as long as you don't want it at the weekend.

Claw, when you test again, get some Selleys 'Platinum' and 'Floors and Decks' they are both polyurethane glues that expand (but not as much as the liquid Visegrip or Selleys) they are sold as 'liquid nails' products which I feel is a bit of an insult because unlike the other liquid nails products these are incredible, I have done some rough tests and found the Selleys 'Platinum' to be 30% stronger than the "Floors and Decks" and 60% stronger than the PVA, I didn't test any liquid Polyurethanes because I've long given up on them, for gluing wood at least, they are just too foamy I believe, they are fantastic for masonry though, I glued down a rocking toilet 5 years ago, and it's still solid.

I find it odd that they are not more more popular with wood workers, maybe something psychological? not being runny or that they come in a silicone type tube?

Only just found this thread!!

I think Polyurethane adhesives are being slightly maligned, as they are only suitable for used in a thin film, with good clamping pressure during bonding.

About three years ago i did a series of tests comparing PVA and Polyurethane adhesives on Jarrah, prior to building a large table and 10 chairs.

As all joints were to be either Lap or Blind lap joints, which could be efficiently clamped, I decided to check out the two systems first.

The test was carried out using a 220mm long cantilever , with a 35*60 mm bond area at the fixed end. A load deflection curve was also plotted for each test to see if creep would be a problem at higher loads,each load test was over an 8 hour period.

On average the PVA failed between 90- 98 KG end load whilst the Polyurethane failed between 138 - 150 KG, with significant timber failure at the joint faces. Later on I did a small number of tests on "techniglue" epoxy gel with similar results to Polyurethane.

What brand of polyurethane glue did you test Paddy?

Cheers
Michael

Originally Posted by Paddy

Only just found this thread!!

I think Polyurethane adhesives are being slightly maligned, as they are only suitable for used in a thin film, with good clamping pressure during bonding.

About three years ago i did a series of tests comparing PVA and Polyurethane adhesives on Jarrah, prior to building a large table and 10 chairs.

As all joints were to be either Lap or Blind lap joints, which could be efficiently clamped, I decided to check out the two systems first.

The test was carried out using a 220mm long cantilever , with a 35*60 mm bond area at the fixed end. A load deflection curve was also plotted for each test to see if creep would be a problem at higher loads,each load test was over an 8 hour period.

On average the PVA failed between 90- 98 KG end load whilst the Polyurethane failed between 138 - 150 KG, with significant timber failure at the joint faces. Later on I did a small number of tests on "techniglue" epoxy gel with similar results to Polyurethane.

Similar results with both Titebond and Selleys Durabond

Hmm, interesting ah Mic, Very simiar test to my own but I didn't get any timber left behind on my breaks. I had good glue coverage (as per the instructions on the tube) and good firm clamp pressure (as per instructions) I got the same or similar result to the one I got on previous tests which also aligned with results I got from normal use.
As Mic said, what brand are you using?

Ok, will have to try them, I tested Sika and Vise on my last few tests.

One difference I notice is that I don't have anywhere the excess glue next to the joint that you have there.
Maybe I am being too stinjy with my glue although I still get squeeze out.