what cleans off unmixed epoxy?

[mashersmasher]

so i used one of those tubes of epoxy to attach some bits on a robot however i neglected to mix it in equal proportions. is there any chemical suited to removing the excess that has now dripped down the outer casing?

 

[ChrisChurch]

Isoprophanol will get rid of any epoxy residue. I use it on my hands too when ever I get any on me. Its very handy to have a bottle around when your doing anything with epoxy.

Chris

 

[mashersmasher]

oh awesome! you can find that stuff at the hardware store eh?

 

[ParkingLotLust]

Its just regular Alcohol (not rubbing alcohol). *Isopropanol You can get it at a drug store, hardware store, grocery store, pretty much everywhere sells it. Try to get the highest % you can find - they sell 70% and 90% around here (% of alcohol to water I believe).

 

[Speakerguy]

Isopropyl Alcohol 91% at the drug store is the first solvent to try. It used to be you could only find it at 70% but now almost every grocery store I look at has it at both 70 and 91%. After that, try acetone but it is VERY damaging to plastics. It is circuit board safe except for plasting wrapping on electrolytics, plastic bodied film caps, and plastic terminal blocks, in general. Other heavy duty solvents inlcude stuff like MEK that you can buy at the hardware store, but these are very very strong and have health risks.

For me, if IPA and acetone won't do it, I go looking for specialized solvents. The last time I made a mess with super glue, I tried both with no success and then went and bought the specialized super glue remover from Duro, and it worked like a charm. So if the above fails you, look for specialized products. I hate to see people resorting to anything stronger than acetone like MEK (methyl ethyl ketone).

 

[jpanhalt]

Denatured alcohol (ethanol) is my first choice as it has the least water in it and is polar. Acetone is my second choice. I use it when I need the solvent to evaporate very quickly. John

 

[Speakerguy]

I use denatured alcohol in my shellac finishes on my woodworking projects. Is it plastic safe? I believe it also has some methanol mixed in with the ethanol.

It reminds my of the bottle of everclear (198 proof grain alcohol from the liquor store) we had in the high voltage lab at a previous job with "For Lab Use Only" written over the label. "Technically, I was using it in the lab...."

 

[mashersmasher]

ok awesome guys! will alcohol damage exposed circuitry though? if so i'll just plastic wrap it

 

[Speakerguy]

No, 91% IPA is perfectly safe for everything. It is very mild.

As for ethanol/denatured alcohol, I haven't tried it on plastics.

 

[mashersmasher]

well the frame is metal so it shouldn't be a problem however i believe the epoxy is a kind of plastic

 

[KMoffett]

I use denatured alcohol in my shellac finishes on my woodworking projects. Is it plastic safe? I believe it also has some methanol mixed in with the ethanol.

Ethanol will damage acrylic plastics...it was a sad experience.

Ken

 

[jpanhalt]

Ethanol will damage acrylic plastics...it was a sad experience.

Ken

Was it pure ethanol or denatured ethanol? What type of acrylic plastic was it? There are many different formulas for denatured alcohol. Some of the formulas contain compounds that will damage styrene and maybe some acrylic plastics. Other formulas do not. If isopropyl alcohol (IPA) does not harm the plastic, pure alcohol probably will not damage it either.

On the plus side, ethanol and pure isopropyl alcohol are great solvents for uncured epoxy. Water is a very poor solvent. So, IPA with water is not as good as pure IPA. The less water the better. Pure methanol will also work, but it may tend to be more aggressive on plastics than IPA or ethanol.

John

 

[KMoffett]

Was it pure ethanol or denatured ethanol? What type of acrylic plastic was it? There are many different formulas for denatured alcohol. Some of the formulas contain compounds that will damage styrene and maybe some acrylic plastics. Other formulas do not. If isopropyl alcohol (IPA) does not harm the plastic, pure alcohol probably will not damage it either.
John

It was lab grade ethanol, and a cast acrylic cylinder with a bonded sheet acrylic bottom. The cylinder was filled with ethanol and after several hours it started to craze, then crack, and then just fell apart in large chunks.

Ken

 

[jpanhalt]

It was lab grade ethanol, and a cast acrylic cylinder with a bonded sheet acrylic bottom. The cylinder was filled with ethanol and after several hours it started to craze, then crack, and then just fell apart in large chunks.

Ken

Ah ha. Crazing is a different phenomenon. Also, some lab grade ethanol contains aromatic hydrocarbons (benzene in the olden days, maybe toluene or xylene today) that while they do not readily melt acrylic, they can cause crazing very quickly. Short, non-repetitive exposure to alcohol is generally OK on acrylic (e.g., Plexiglas).

Acrylic is really a pretty chemically resistant plastic compared to polystyrene (like CD jewel cases). While acrylic is not affected immediately by alcohol, polystyrene will show surface etching after only short exposure, particularly in the absence of water.

John