Garden Rake.

[bc_gold 152]

This is the handle of my garden rake made of laminated wood scraps. Least they could have done was use water proof glue.

[formariz 12,192]

There really is no water “proof” glue. There is water resistant glue which is what they used. The best glue there is for exterior or marine applications is Resorcinol which is urea formaldehyde. I have used in submerged applications and still holding. It is however expensive and difficult to apply having to be precisely mixed. One has to be a bit of a laboratory chemist to have full success with it. It would not be practical or economical to use it on a rake handle . The cost of the glue would exceed the cost of the rake. On handles like that one has to avoid letting handle in the rain absorbing moisture through end grain. Sometimes I actually make a cap out of copper flashing for the end of a tool handle that is exposed to water frequently. 

 

 

Urea formaldehyde. Two part glue. This is left over from a job . Its shelf life is basically over so it has to be discarded. Close to 80 dollars worth of glue to be discarded. 

 

 

Edited 21 hours ago by formariz

[Wayne0 1,357]

If you kept it coated with BLO, it would have been fine. Time for a new rake.

[Achto 29,858]

3 hours ago, formariz said:

Resorcinol which is urea formaldehyde

 

Wait... urine and embalming fluid makes glue !?!?!?!? 

 

Urea is a nitrogen-containing waste product formed from the breakdown of protein in the liver, filtered out by the kidneys, and excreted in urine. It is also a widely used chemical with diverse applications, including a high-nitrogen fertilizer

 

Formaldehyde : Embalming fluid - Commonly used in mortuaries.

 

I thought Urea was for making corn grow and formaldehyde was for keeping things from rotting.

 

What mad chemist decided to mix these together for glue ???? 

 

Made me think of a morbid joke, but I'll keep it to myself. 

[ri702bill 10,070]

Disposal, per Spectrum's SDS sheets states that raw components are hazadous, whereas the mixed & cured  combination are not... Interresting....

[formariz 12,192]

12 minutes ago, ri702bill said:

Disposal, per Spectrum's SDS sheets states that raw components are hazadous, whereas the mixed & cured  combination are not... Interresting....

Correct. Cured product is supposedly harmless. Until then it is toxic. Cured product is also basically impossible to remove such as if spilled on floor. Makes for a thick glue line which destroys any steel cutting edge. It resembles glass. Accurate  mixture of the two components is crucial for success. I use a digital scale to measure portions. Speed also crucial since it sets rather quickly. Using it specially on large areas is an exercise in accuracy, efficiency , organization and discipline. No room for forgetting something or any “oops”. 

[formariz 12,192]

28 minutes ago, Achto said:

 

Wait... urine and embalming fluid makes glue !?!?!?!? 

 

Urea is a nitrogen-containing waste product formed from the breakdown of protein in the liver, filtered out by the kidneys, and excreted in urine. It is also a widely used chemical with diverse applications, including a high-nitrogen fertilizer

 

Formaldehyde : Embalming fluid - Commonly used in mortuaries.

 

I thought Urea was for making corn grow and formaldehyde was for keeping things from rotting.

 

What mad chemist decided to mix these together for glue ???? 

 

Made me think of a morbid joke, but I'll keep it to myself. 

 Many things are used for a variety  of products. Much of MDF and particle boards are made using formaldehyde products. I worked extensively for NYC Metropolitan Museum of Art and anything used in there had not only to be fire resistant and retardant but also free from formaldehyde emissions. Materials for those jobs were comparable to the price of gold. 

[Beap52 1,663]

You-all talking glue way over my limited knowledge of this subject.  Interesting conversation though.

 

I've had pretty good success with polyurathane (Gorilla Glue) on projects.  I built the balustrade below in 2005 and used Gorilla Glue.  So far it's held up.  The sawn ballisters were made from cedar.  (At that time, #3 cedar was often times used as roof decking so I picked out the better boards for my railing.)  I bored something like 800 holes in the production of the handrail and the spandrels. 

 

Unfortunately, the wooden posts I purchased at the lumber yard didn't last even ten years.  (They had a hole in the center the length of the posts from top to bottom.  I cut a hole in my porch floor and notched the top of the wooden posts hoping that air could circulate and therefore help the posts to dry and last longer but that was of no value. I replaced them with vinyl posts.)  I have one ballister that is getting punky but the rest have held up well. 

 

Good think I have opportunity to join this post tonight. Tomorrow it will be too cold to be barefoot on the front porch taking photos!

[bc_gold 152]

I recently made, sodium silicate aka water glass to use on my wood projects.

 

Sodium silicate can be used as a wood finish

to improve durability, fire resistance, and pest control by penetrating the wood and forming a glassy, inert layer that strengthens fibers and repels moisture. It is a non-toxic, environmentally safe option that doesn't emit harmful VOCs. Applications range from industrial treatments for structural wood to finishes for musical instruments and decorative projects

[wh500special 2,341]

Epoxies are a good option for water resistant adhesives too.  If you stick to those that are bis-phenol A (BPA) types you’ll avoid the formaldehyde emissions issues.  Might sacrifice some flammability resistance though…and there’s the whole hormone-imitation thing as well but that’s another kettle of fish. 
 

We used to make some specialty composite parts that were used in deep ocean environments.  Epoxy (almost) across the board.  Of course, no wood there.

 

I didn’t realize resorcinol adhesives were still common.  They’re from the phenolic polymer family which used to be cutting-edge for making plastics (circuit boards, Bakelite, etc) but they aren’t as favored or common these days.   There’s a lot more epoxies, acrylics, and other specialty adhesives available now.
 

As an aside, Cas mentioned mixing them properly.  He’s absolutely right.
 

There’s a temptation to fudge the mix ratio of two-part adhesives (and other materials) in an attempt to adjust cure time, get a harder cure, make it stronger, or whatever.  The problem is this ALWAYS compromises the chemistry of the mix and nearly always results in an inferior product. 

 

The manufacturer will usually have you blend the components in a perfect ratio where nearly every molecule of both components are consumed or reacted together with no excess of either one.  This is the stoichiometric ratio.   wandering in either direction will result in something being left over and the other being in short supply.  This results in unreacted stuff - basically a contaminant - inside the final plastic.  This will translate into different physical properties than you paid for.  
 

Almost always, this means weaker.  
 

In an epoxy or phenolic for instance, adding additional hardener will leave surplus gooey hardener dissolved in the final product.  Not good.  Also, it can force the stuff that does react (cross link) to form a different network of bonds than you wanted.  Those are typically also the bonds you’re asking to reach out and latch onto available sites on the substrates.  Also not good.  
 

You can also change the rate that things happen and further disrupt that network.  

There are exceptions.  Sometimes in industry we go off ratio as our process’s kinetics might not allow mixing to stoichiometric.   Or we have a brittle system and we know that flooding with a calculated amount of extra hardener can soften things up and somewhat toughen the result.  But there’s a lot of mix-test-mix-test iteration going on to get a desired and repeatable result.  

 

My point is, the mix ratio the manufacturer gives isn’t arbitrary.  Don’t be suspicious of a nice ratio like 4:1 or 2:1 instead of 3.1415:1. Don’t assume they rounded it off to make it easier.  Rather, I can almost guarantee they’ve added controlled diluents or fillers to make the measuring work out easier.  
 

Anyway, this got long.  I just wanted to mention epoxies and look what happened. 
 

Steve
 

 

[formariz 12,192]

Epoxies are also good with wood but in my experience only with smaller jobs . With very large areas to be glued the setting time and spreadability is always a problem. One also has to be knowledgeable as to how much to make prior to start gluing. Not only the area has to be taken into account but also very important how much the wood will absorb. For example the same area of oak requires much less glue than cedar. With both surfaces having to be coated within limited time to do so and to clamp them properly things can turn disastrous very quickly. It’s always a nerve wracking experience. Somehow things also fit together better before glue is applied. 

[formariz 12,192]

2 hours ago, wh500special said:

Anyway, this got long.  I just wanted to mention epoxies and look what happened

 And it all started over the humble rake handle. Good conversation. However to all reading this understand that these glues are many times dangerous to your health and regardless of how careful you are and how much protection you use there is always exposure to it. It’s smart to think about it before using them and perhaps decide that it’s not worth the risk. I have been diagnosed with something incurable which is attributed mainly to exposure to solvents. Through out my career I certainly been exposed to quite a lot. Specially when one is young and really inexperienced in life we do what needs to be done but without thinking of the possible or potential consequences. Be careful.

Edited 12 hours ago by formariz

[JoeM 8,905]

9 hours ago, ri702bill said:

mixed & cured  combination are not... Interresting

I know some time ago the trash collection folks would take paint that was cured. The said to open the top and let the left over contents harden then dispose in trash. 

I am not sure about it now. I did find it takes some time to get a quart of paint to harden. 

 

the newer rakes come with a rubber handle cover . I still have one old one that is one piece wood but metal is worn. It is best not to leave them outside when not used anyway. 

[squonk 44,631]

Best waterproof adhesive I have ever seen.............Automotive Windshield Urethane.