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+-- Thread: Liquid Nails fail (/showthread.php?tid=7061338)
Re: Liquid Nails fail - John Mihich - 07-24-2015
I don't believe LN glue joint is suppose to be stronger than the wood. I have seen a number of times people remove items that were glued with LN and the glue joint came apart. I know PVA glues are suppose to have a strong glue joint.
I agree that glue isn't needed for headers.
Re: Liquid Nails fail - Phil Thien - 07-24-2015
tomsteve said:
I've built a LOT of houses.
I've built a LOT of headers. Probably in th thousands.
Not once did I use glue.
But I also don't try and use twisted lumber for headers.
This is the key. There are lots of places you can use some lumber with a little twist but a header isn't one of them.
Re: Liquid Nails fail - tomsteve - 07-24-2015
Phil Thien said:
[blockquote]tomsteve said:
I've built a LOT of houses.
I've built a LOT of headers. Probably in th thousands.
Not once did I use glue.
But I also don't try and use twisted lumber for headers.
This is the key. There are lots of places you can use some lumber with a little twist but a header isn't one of them.
[/blockquote]
We tried to save that for the end of a job a d places like truss lacing or roof kickers.
If I'm not mistaken, and I may be, liquid nails is to be used in conjunction with mechanical fasteners,too.
Re: Liquid Nails fail - Bob10 - 07-24-2015
Hey you can use it to hold back those doors!!
Serious note PL would have held it but again twisted lumber for a header is not the way to go
Re: Liquid Nails fail - Axehandle - 07-24-2015
Bob10 said:
Serious note PL would have held it but again twisted lumber for a header is not the way to go
Don't be so sure. Bowed wood will do what it wants. The LN was probably general construction adhesive and as such it would have done the same thing that Titebond or Loctite construction adhesive would have done. There are different types of PL just like there are different types of all the others.
As mentioned before, use the glue and fasteners. Or in the case of a header, don't use twisted, cupped, bowed, etc. lumber and also it is not necessary to use glue.
Re: Liquid Nails fail - Curlycherry - 07-25-2015
theeviltwinn said:
Liquid Nails remains somewhat flexible when cured. This allows it to handle small movements in the wood without breaking the bond. The down side is because it remains flexible a constant force on the joint can cause the glue to fail. Glue and screw are the way to go.
Twinn
This is correct. LN is a sheer increasing adhesive. Make a string of it and let it cure and you can snap the string in the middle. Put it between two blocks and slide them face to face and it will be impossible. Pull the two pieces apart at 180 degrees and they come apart remarkably easy.
A Squared was spot on with his description too.
<.....works next door to construction adhesive group.
Re: Liquid Nails fail - SkyGlider - 07-25-2015
Thanks for your additional comments folks.
The 2x6 was not twisted. It just had a bow to it. Screwing the two pieces back-to-back straightened it out very nicely. I wouldn't hesitate to do that again under the same circumstances. But next time NOT using LN
.Learned that Liquid Nails should only be used for stuff like holding wall boards to studs. "I'll" never use it again for anything requiring strength. When gluing two pieces of similar wood together (similar expansion & contraction), I'll use a glue that dries hard from now on.
Is there any glue that comes in a caulking gun tube that dries hard? I'm guessing none.
Skyglider
Re: Liquid Nails fail - Mr_Mike - 07-25-2015
Without knowing how much of the surface area was glued, one cannot determine if the glue underperformed.
Headers don't need glue. It does nothing except keep your crappy lumber less bowed. Spike them together with nails and be done with it. Screws aren't the right fastener either.
I'd definitely not use gorilla glue. That stuff should be banned.
Re: Liquid Nails fail - Curlycherry - 07-26-2015
Actually adding LN to lumber, bowed or not adds a LOT of increased performance in sheer mode. If you want to use it for headers that is fine and it will add strength. Whether or not the strength is needed, that is a separate issue. But in general two pieces of wood stuck together (face to face) with screws will benefit greatly with even just a little LN.
Re: Liquid Nails fail - Anthony W - 07-27-2015
Mr_Mike said:
Headers don't need glue. It does nothing except keep your crappy lumber less bowed. Spike them together with nails and be done with it. Screws aren't the right fastener either.
That's relative. Which screws? The right screws will be better than nails. Wood screws or lag screws, yes. Sheet rock screws, no.
I think I saw an explanation on screws versus nails on an episode of Ask This Old House. Tom (I think) said to use glues and nails. When asked about screws he replied "I don't recommend screws because most people will use sheet rock screws. Sheet rock screws have a small shank than the nails therefore are not as strong. I would recommend wood screws with a shank with a diameter as large as the nail. But most people forget that part and fall back to sheet rock screws."