Contact Adhesives

[Handstitched]

G'Day,  

Out of some of the challenges in leather work, one is just an annoyance .Contact adhesives going off in the tin before its all used. Doesn't matter what brand.   This is  due the frequent opening and closing of the tin, and while I ensure the tops and edges of the  tins are clean and tap the lid down firmly after each use , over time they go off with still some left. ( summer is a real *&^%tch for adhesives )   I only buy 500ml tins ( the smallest available here)   because of this.  I was buying 1litre tins, but I was wasting too much and it was costly. 

Is there any way of thinning / rejuvenating/ softening  contact adhesives using a particular ( and  available) chemical ?( not acetone, I've tried it)    Alternatively, I could contact the manufacturer/s  for advice. 

Thank  for any help. 

HS 

Edited May 21, 2019 by Handstitched

[bermudahwin]

I put in a splash of Ronson Lighter Fuel, right or wrong.

It works and I've yet to blow up the workshop.

[coma44]

I see that Barge cement offers a thinner, guessing this could be used. I have only used small bottles of weld wood contact cement so far. Just ordered a quart to save money but need some storage jars with the applicators to help prevent the same issue your having.

 

[Dwight]

This will sound silly, . . . but I finally whipped that exact problem with a plastic peanut butter jar.

Actually does not "fully, . . . 100%" end the problem, . . . but sure makes it a whole lot less of a problem.

AND, . . . I only use Weldwood brand, . . . which can be lightly diluted with Acetone (I believe it is part of the original formula).

Anyway, . . . it works.

May God bless,

Dwight

[Double Daddy]

Like Dwight, I'm a "Weldwood Original (red can)" disciple...been using the stuff for years on woodworking, laminations, etc before I got into leather...the stuff just plain works...also keep Acetone around for thinning. I've used mason jars or (currently) an old pickle jar as my glue pot. But...leave it to Dwight to give us the empty Jiff jar for glue....practical size and resourceful. Works for me!

[arashikage]

Depending on the brand of cement, they may have their own thinner. It's best practice to use the same brand of thinner as cement, Barge with Barge or Master with Master, ect. But they all tend to work. If you know you're not going to be using it for an extended period you can thin it down quite a bit and just leave it. 

[bullmoosepaddles]

You may try Bloxygen. It is basically ultra pure Argon gas, packaged similar to the computer/keyboard dusting gases.

It is a heavier than air gas that settles on top of the finish in the can providing a oxygen free barrier. Not tried it on contact adhesive yet. But it sure works on polyurethane and paints.      

Place the lid loosely on the can of finish, stick the straw from the Bloxygen into the container and give a two second blast then seal the lid. Like I said it works for my poly. 

[RockyAussie]

Normally I buy 3x20 litres at a time along with a drum of the thinners for it as we need to thin it for the glue machines and for spraying as well. I ran short of the thinners once and found that I could use general purpose thinners (GP Thinners) be that it was not as good as the proper thinners. Your paint shop will be able to help.

[dikman]

I use Sika glue (from Bunnings) as it's a bit thinner than some of the others and works well. Like the op I only buy small tins. I don't know what the thinning agent is that they use but I found that adding xylene seems to work ok. I'm going to try a bit of automotive paint thinner, as it "should" work and is cheaper.

It's also better to add the stuff before it starts thickening too much.

Edited May 21, 2019 by dikman

[Handstitched]

G'Day and thank you so much for your replies  

@RockyAussie I take it thats the same thinners you use for spray painting? 

@hwinbermuda I might try that,thanks   

I use either ' Selleys' Kwik Grip or ' Parfix  '  ' . I have found they  both do the job quite well. 

Now, this bit may seem odd, but, the remaining adhesive in the Parfix tin was going off, so, I poured a little bit of  the 'good'  ' Kwik Grip' into the Parfix tin and sealed it well and left it for a few days . , that seemed to have softened it up a bit.  

I didn't know that there are  specific thinners for adhesives,( we learn something new every day eh )  so you've all been very helpful. This I will look into further.  Thanks  

HS 

[Handstitched]

G'Day , 

yes,  I did look into it further. But this was at the back of my mind the whole time ,  'Toluene' . 

The product is ' Diggers Toluene Contact Adhesive Thinner' ( Australia)  . I know all about this stuff, I worked with Toluene for over ten years + in my  fibreglass pool days . 

HS

[Matt S]

My workshop rarely gets as hot as yours does, I'm sure. However my contact cement (proper toluene stuff) does thicken over time.

To avoid this I use one of those glue pots with the lid. I try to only decant from the big tin what I'll use that day. It doesn't stop evaporation so I do need to add thinners every now and then but it does slow things down a lot, since I'm opening the tin far less often. It also reduces the amount of vapours hanging around the shed, is less messy than working directly from the tin and provides a handy place for the glue brush to sit.

https://www.leathercaresupply.com/products/ts-boy-glue-cement-adhesive-pots?variant=12934815973459

[mikesc]

What is going to work to dilute / thin ( or re-dilute / thin ) any adhesive.."contact" or otherwise, is going to depend upon what the original dilutant* / thinner was ..
Not all adhesives or contact adhesives are the same..
So..best is to find the MSDS for the particular product, see what the "thinner" used is..and get some of that..
Some "paint" spray thinners ( note there are as may different kinds of thinner as there are pain ) are "oily", ( these are often used to clean spray equipment ) some are re-cycled ( these tend to smell more strongly ) some are "slower" ( these are used for amongst other things spraying the metallic paint "base coats" of two part metallic paint finishes, the second part being two pack acrylic or polyester clear coats )..Some will dilute epoxy paints and / Fillers, but will not dilute polyester paints / and fillers..

There are so many non compatible combinations of paints, adhesives, fillers and "thinners" that the only way to know ( and to stay safe..some mixtures are more dangerous than you'd think ) and to actually have a thinner that works..

Is to read the MSDS..and get what was used originally ..if you cannot get it..then try to test with a similar molecule.( wikipedia is your friend )

To prevent the adhesives "drying out" ( the original thinner evaporating slightly and the remaining part oxidising ) ..after each use, reduce the amount of air in the container, seal it tightly, "air tight", and keep it cool ( fridge temp ..3°C to 6°C and in somewhere dark if the container is transparent or translucent..

Bring it up to room temp by bringing it into the room an hour or so ( larger volumes need more time ) before you need to use it.
Don't leave brushes in it..Even the kind that are built into the lids, they contaminate the adhesives and make them go off faster..Adhesives that go ff can seem fine for months or even a couple of years, and then suddenly go off..They do have "shelf lives" and "sell by dates" and "use by dates"..Check the "use by date" when you buy, don't buy something that has been sitting in a hot warehouse / shop ( or a frozen warehouse / shop ) for a year or so and that only has a year or so left.

Unless you are like Brian and use large amounts, don't buy "big", it will go "off"..( and you will not be saving money ) that is the nature of adhesives..re-thinning can work, but it is not an exact science, some of the molecules in there will not be quite the same when re-thinned as they were when it was made..

HTH :)

Apparently , if you live in California..none of the above will be relevant ..? ;)

* I would say "diluant"..I forgot the English word..and my speelchucker thinks dilutant is wrong..::sigh::

Edited May 22, 2019 by mikesc

[Handstitched]

G'Day and thank you once again for your help.

I've just ordered 1 ltr of  ' Diggers Toluene Contact Adhesive Thinner' from my local hardware shop . Its $16.00 Au . 

My local hardware doesn't keep it ,  understandably ,  as its not very nice stuff if you  don't know  what you're doing with it. 

P.S. (a bit off topic,  Our local hardware shop  is one of those 'ye olde' ones , with old creaky wood floorboards, one on one service,  and  where you know where everything is....not like those hardware chains where it takes a better part of an afternoon  just to find a packet of screws  and no-one to help you ) 

HS 

[Matt S]

2 hours ago, Handstitched said:

P.S. (a bit off topic,  Our local hardware shop  is one of those 'ye olde' ones , with old creaky wood floorboards, one on one service,  and  where you know where everything is....not like those hardware chains where it takes a better part of an afternoon  just to find a packet of screws  and no-one to help you )  

Old-style hardware stores are great. We have one of them down the road. I was looking for a mattock for a garden project recently (needed to move a fair chunk of clay soil but not enough to mechanise the job). Tried 5 different DIY and trade suppliers. What few had listed one on their website had no local stock. Walked 5 minutes down the road into the hardware shop. Picked one off the wall, paid over my £20, exchanged the traditional joke about burying the mother in law and I was away back down the road. 15 minutes after I left the house I was chopping lumps of clay out of the ground the size of a car battery.

Contrast against the local big-name DIY shed, where I can barely find someone to take my money, the prices are all wrong, and 9/10 pieces of wood looks like an avante-garde corkscrew.

[dikman]

The Sika adhesive I use lists naptha solvent, toluene and acetone! Guess I've got a choice.

[Handstitched]

@dikman two of those chemicals, acteone & toluene  I  used frequently ' back in my fibreglass pool days' . Both are to be treated with respect, especially toluene,  just one minute drop of that in your eye makes you turn into Hussein Bolt...to the wash room.   We did have a 240ltr drum of  industrial strength  Methylene chloride in the factory, , I kept my distance from that and never used it  , it had         ' skull & cross bones' on the label   

I am hoping a small investment in some toluene  may save me money in the long term , by not wasting so much adhesive and making it stretch further.  Any cost savings in business  during challenging times is a plus   

HS 

20 hours ago, Matt S said:

Old-style hardware stores are great.

I agree. Our old hardware shop  does have its historic value to the locals too. If they don't have what you want, they can get it. 

HS 

[ABHandmade]

Same problem .

Now I significantly reduce the rate of adhesive drying in the can by simply placing the closed tin in a plastic bag with a clasp from which the air was removed as much as possible.

And I use a small container, pouring into it from a large tin the amount that is needed for current work.

Edited May 24, 2019 by ABHandmade

[mikesc]

Methylene chloride is evil stuff..I can vividly remember the sting of the chemical burns from it from splashes onto my hands and wrists..left no scars fortunately, other scars, but none from that...used to be in quite a lot of things ..like "polystripper"..

Another who has worked, works with large quantities of ( boats, custom bikes and cars, and sculptures ) resin ( poly and epoxy ) ..aahh "the smell of styrene in the morning"..the joys of Cyanoacrylates and catalised two part "clear coats" that have made it through the masks and respirators....leather and thread is a lot more friendly.. :)

[johnv474]

Each company makes their own thinner, but almost any of the All-Purpose Contact cements have compatible thinners.  BUT, NOT Multi-Purpose Cement.  There is a difference and these families are not compatible. Barge, Master, and Weldwood all use a similar MEK solvent combo for thinning (referring to thinner for All Purpose Cement, not their other products like vinyl cement).

A quart of thinner should cost about $13.  It does a great job of removing oil, etc., from leather surfaces before gluing, also.

The suggestion I give people is to buy cement by the quart and then to get a smaller 8-16 oz glue pot from Atco or S&J.  The glue pot is basically a Mason jar made of plastic, with brush that screws into the lid.  The brushes are wider than the ones that come with the cement, and hold way more, but the depth of the brush is adjustable, so you can have just the tip of the brush touching cement.

By having a separate glue pot, you can open your quart, pour in roughiy 8 oz of cement to the jar, then close your quart can.  You will lose less solvent by having less of the cement in a smaller container and just using that.  However, investing in a quart of thinner is worth it to revive drying cement (as well as for cleaning off tools and cement spills, etc.)

[Handstitched]

G'Day , Just a quick update.

I received my tin of Toluene recently, and already its worked. ( But  as soon as I opened the tin, the smell immediately  brought back memories of my fibreglass pool days,  I don't miss it ) 

I put a little into the tin in the morning  , sealed it, and by the arvo, it had already  turned 'the almost solid lump'  of adhesive into something I can use. 

Over time this will hopefully save me a lot of $$$ in expensive adhesive. 

Yey ,  I like it when stuff works  

Thanks for all your advice and input . 

HS