I've come unstuck!!

[hoodpage]

Hi all
I've made a couple of rustic reclaimed wood coffee tables for a craft fair I'm doing in a couple of weeks time, but I've got a big problem, I've been using polyurethane glue to make all my pieces, but I think the finishing oil has reacted with the glue and everything is falling apart at the seems. The oil has turned the glue into mush, the legs are falling and the table tops have fallen in half.

Does anyone know of a better, stronger, fast curing glue that doesn't react with my oil?

PLEASE HELP!!! Thank you Liam

 

[joiner_sim]

Try some exterior wood glue, or cascamite and there should be no problems.

 

[Ironballs]

Titebond 3 and Danish Oil seem to be happy bedfellows in my experience

 

[antonello]

Epoxy resin.....

 

[newt]

I am surprised it is the oil that is causing the problem, are you sure. If it is the oil you should contact the glue manufacture as lots of folk use oil.

 

[GazPal]

How old is the glue? Oil finish is normally fine with most adhesives.

 

[JoinerySolutions]

You state that you are using reclaimed wood.... what wood is it and was it previously treated (say chemically)?
Some timbers need special treatment prior to glueing and some treatments can cause problems. I doubt the oil is the cause of your joint failure, what oil did you use?

Rob.

 

[hoodpage]

Hi all
me again, the glue is about 6 months old but I can't find a use by date on the bottle, what makes me think its the oil is because the tables are solid pieces until I oil them and then they fall to bits, the oil I use is Liberon finishing oil, its easy to use and gives a really good even finish.

Thanks all.

 

[ondablade]

It seem odd that a proper polymerising polyurethane should be attacked by an oil - they are generally regarded as having properties like epoxies, but with added chemical resistance and flexibility/toughness at the expense of being a little more difficult to handle. The oil cures anyway, and is presumably inert after that.

Could it be a bum batch of adhesive, or something to do with the working conditions or contamination of the wood?

I don't know enough to be specific, but one caveat might be that there are many many formulations that use different chemistries - including some compounds that strictly speaking are polyurethanes in name only as they they have only minor amounts somewhere in the mix. (they are at best 'polyurethane modified')

Another is that despite this there are chemicals that will attack them, especially when not fully cured. They don't seem to like acids and alcohols, but most are good with oils (but perhaps there are additives in danish oil that would cause problems???) for example.

My memory is fuzzy, but i think some don't like to be coated with/contacted by some various fairly ordinary compounds until they are fully cured (which can take up to a week) - it's maybe not too hard to bu***r up the curing reaction. e.g. most of the single part variety (like silicones) use moisture from the air and the substrate to drive the cure, this could easily be displaced/excluded. Or contamination of some sort could be messing it up.

It might be worth digging out a technical data sheet (TDS) for the specific adhesive on the web or from the maker, and/or talking to their tech support ...

 

[antonello]

Just wondering: has the bottle been stored at a temperature constantly over 5 °C? (even before buying it: this once happened to me with some paint......)

If not, this certainly has affected his bonding properties.

 

[jimi43]

At the risk of starting another controversy regarding polyurethane glue...I simply cannot get on with the stuff.

I have tried everything...from closely following the instructions to using different brands.

The first I used was Gorilla glue which is absolute rubbish.

I thought it might be the brand but I tried Titebond Poly since I liked the colour purple bottle label (ha!) and since Titebond is generally very good glue.

I have gone back to Original and III as I simply find that I can't get it to bond correctly, it makes a huge mess....sticks to yer fingers and is generally disappointing.

I am going to be shot down in flames but what happened to you happened to me on trying to repair an old oak table top for outside use...it just fell apart after a while and was dreadful to try to get off to start again.

Titebond III for me or Araldite or West Original epoxy anytime.

Jim

 

[matthewwh]

Better that it's happened now than after you've sold the stuff. Get in touch with your supplier and explain the problem - if they've an ounce of wit they will withdraw the product or at least the batch and verify through testing that it's good before they put it back on sale - and thank you for raising the issue into the bargain.

I would scrape (as far as you can) and re-glue the surfaces with new glue, as far as I'm aware there are no woodworking glues on the market that should be adversely affected by danish oil. #

 

[oakfield]

To confirm that it is the oil at fault, would it be worth putting a couple of blobs of glue on some scrap wood, then when they are fully cured apply a little oil to one and see what happens?

At least then you will know for sure.

 

[GazPal]

Apart from potential timber treatments (Pressure, etc.) that could have negated the glue bond, a lot depends on how long the glue was stored and storage conditions before and after it was opened. Many have a shelf life of up to a year - once opened - but that tends to involve ideal conditions and quite often fridge storage (As with Titebond Original).

Other possibilities could be linked to joint starvation or over gluing (Using too much glue within a joint) as both have an effect on bond, but seeing that the glue appears not to have cured I'd tend to think along the lines of "past it's sell/use by date" instead of a poor reaction with the timber used.

It often pays to source adhesives via high turnover suppliers as their stock tends not to be kept behind the counter for months on end.

Try very lightly spritzing a couple of pieces of scrap timber with water then add a little glue and stick together to check and see if the glue reacts in the way it should.