Isopropyl Alcohol vs Methyl Hydrate Alcohol

Andrew Shadow

Site Supporter
Joined
Jan 28, 2012
Messages
5,127
Location
Montreal
Bike
2009 ST1300A9
I know that there a few people on here who have worked in the chemical industry.
For those with that kind of a knowledge base, I would appreciate your thoughts on the below question.

I have, for a very long time, used isopropyl alcohol as a cleaning agent. I use it for everything from cleaning the moly off of the final drive, to cleaning O-rings before installing them, to cleaning electronic parts before and after soldering them. It works well in many different applications, doesn't require a hazmat suit to use, doesn't damage most materials or finishes, it doesn't damage rubber O-rings, seals, gaskets, hoses, etc., is easy to work with, evaporates quickly, and was always very easy to find and was cheap to buy in large quantities. I always bought it in one gallon jugs at hardware stores for 1/3 of the price that it sells for in pharmacies. I recently ran out and went looking to buy some more. For some reason it is hard to find now. Every hardware store/renovation centre that I went to no longer carries it. The one place where I did find it wants an arm and a leg for it. The 70% pure was something like $55.00 for a gallon and I think that the 90% pure was over $70.00.

All of the hardware stores are now stocking methyl-hydrate alcohol instead. This is very reasonably priced at around $12.00 for a gallon. I bought a jug but I have never used methyl-hydrate before so I do not now what limitations I should put on its use. I found out the hard way that it removes paint very efficiently whereas there is no danger of that with isopropyl alcohol. Thankfully it was not on something that caused me much anguish.

Given my above description of what I used the isopropyl alcohol for, below are my questions for the chemical experts;
- Can I use the methyl-hydrate alcohol for the same purposes that I was using isopropyl alcohol for?
- Besides removing paint, what else will it damage that I should keep it away from?
- Will it damage rubber hoses, O-rings, seals, etc.?
- Is it just as suitable for cleaning solder joints before soldering as isopropyl alcohol is? Or does it leave some kind of residue that will affect the solder joint?

If methyl-hydrate is not that good a substitute for isopropyl alcohol, for all of the things that I was using it for, is there something else out there that can as effectively replace isopropyl alcohol for the same uses that doesn't cost an arm and a leg?
 
Last edited:

bdalameda

PaleoCyclist
Joined
Jan 13, 2009
Messages
2,440
Age
67
Location
Salinas, California
Bike
Africa Twin
Methyl-hydrate alcohol is also known as methanol. It works fine for cleaning but the vapors from it are more toxic and less pungent that iso-alcohol so be careful with it. It also can be destructive to aluminum and can make some vinyl hoses and parts shrink and harden up when exposed to it. I used to use methanol as a fuel or fuel blend when racing go-karts many years ago. Fuel lines became hard and brittle when using it and if residue was left inside an engine the aluminum engine components would become severely pitted. We used to have to run oil mixed gasoline in the engines after running it to prevent damage from occurring.
 
Last edited:
Joined
Mar 6, 2024
Messages
42
Age
70
Location
Detroit
Bike
2003 Honda ST1300
Several comments.. a) for mechanical parts I'd prefer kerosene which has good cleaning properties and leaves a protective film on the part that prevents corrosion for a short time; b) isopropyl alcohol (IA) is normally used for plastics and similar finer parts; c) if you really liked the IA and now you'd rather use the other one I'd get the MSDS for that and see actual properties and uses straight from manufacturer; another option may be denatured alcohol from various sources.
 
Joined
Mar 13, 2012
Messages
5,071
Location
soCal
Bike
'97 ST1100
STOC #
687
I did a quick search and CVS pharmacy has the 91% version in stock here for $6.49/quart. You must have a similar drugstore chain where you live, have you searched there yet?
 

wjbertrand

Ventura Highway
Joined
Feb 8, 2005
Messages
4,418
Location
Ventura, CA
Note: make sure to wear gloves (as well as having good ventilation) when using methy alcohol, also commonly called methanol. It can be absorbed through the skin and is quite toxic compared to isopropyl alcohol.
 
Joined
Feb 10, 2011
Messages
97
Location
Iowa
Bike
82 VF750S Sabre
Note: make sure to wear gloves (as well as having good ventilation) when using methy alcohol, also commonly called methanol. It can be absorbed through the skin and is quite toxic compared to isopropyl alcohol.
Methanol is extremely toxic. It causes blindness as well as other issues.

I have no idea about its cleaning properties.

Neal
 

STRider

Site Supporter
Joined
Mar 17, 2020
Messages
1,114
Age
64
Location
Oregon
Bike
2012 ST1300A
STOC #
50
In a semiconductor cleanroom we use 90% IPA for the vast majority of our surface wiping tasks. However when dealing with optics or other critical surfaces, particularly those that are subject ti high intensity, high energy, short-wavelength, radiation (aka. 'light', not A-bombs or nuclear reactor radiation)... I digress... we use pure methanol because it evaporates completely leaving no residue, whereas IPA leaves an organic mono-layer which would react with said radiation.

For all those reasons stated above, I'd minimize the use of methanol (or methyl-hydrate alcohol) to those applications where it's indicated as the best material.

Methanol is also what has been referred to as 'wood alcohol' and the cause of the stories about going blind from drinking bad hooch.
 

STRider

Site Supporter
Joined
Mar 17, 2020
Messages
1,114
Age
64
Location
Oregon
Bike
2012 ST1300A
STOC #
50
Methanol is extremely toxic. It causes blindness as well as other issues.

I have no idea about its cleaning properties.

Neal
It cleans exceptionally well, if you're using it to remove the right material from the right surface.
 
Joined
Feb 27, 2012
Messages
815
Location
central NJ
Bike
2010 Honda ST13
Methanol is extremely toxic. It causes blindness as well as other issues.

I have no idea about its cleaning properties.

Neal
Does denatured alcohol have enough methanol that we should be careful about skin contact?
 
Joined
Aug 30, 2020
Messages
1,189
Location
Williamstown, ON
Bike
'06 ST1300A
I did a quick search and CVS pharmacy has the 91% version in stock here for $6.49/quart. You must have a similar drugstore chain where you live, have you searched there yet?
Yes, it’s called Wally World up here too ;)

 

wjbertrand

Ventura Highway
Joined
Feb 8, 2005
Messages
4,418
Location
Ventura, CA
Does denatured alcohol have enough methanol that we should be careful about skin contact?
Yes, it boils down to amount and duration of contact. I’d handle it the same way as pure methanol, but that’s my career in materials and chemistry precautions coming out.
 
Joined
Feb 10, 2011
Messages
97
Location
Iowa
Bike
82 VF750S Sabre
Does denatured alcohol have enough methanol that we should be careful about skin contact?
I only know that methanol is toxic. Wikipedia has a formula for denatured alcohol. Medical sites suggest that it can cause irritation when used as a carrier for beneficial products. I would tend to use protection wear for this reason. Or be very careful with application and wash with a lot of fresh water immediately after.

Neal
 
OP
OP
Andrew Shadow

Andrew Shadow

Site Supporter
Joined
Jan 28, 2012
Messages
5,127
Location
Montreal
Bike
2009 ST1300A9
I did a quick search and CVS pharmacy has the 91% version in stock here for $6.49/quart. You must have a similar drugstore chain where you live, have you searched there yet?
Bought a 500 ml bottle for $8.99 CDN, but I bought at tye first place I came to without shopping around.
 
Joined
May 27, 2021
Messages
1,059
Age
63
Location
Coquitlam British Columbia Canada
Bike
2009 ST1300
I think you might want to remember that while Madame Curie probably never worked at a hardware store, she had a certain glow, at least for a while. If I'm not mistaken, I think history suggests that her husband told her that but, sadly, not for very long, because, well, he was her helper, and for some reason, didn't hang around very long.
I used to work on a benzene recovery system for an oil company through a service company. Every now and then [and it wasn't often] environment canada would send out someone to check for emissions, but here's the thing; they would send them out between defrost cycles when the iced benzene melted, collected, decanted and was pumped back into one of the farm tanks.
It was a good gig, but getting to my point, oh yeah...
Why bother with any of that [chemical XXX] in this day and age, it becomes a bit like what John Lennon said; "hey, do you remember the '70s ? wasn't that a drag, glad it's over, hope you made it.
 
OP
OP
Andrew Shadow

Andrew Shadow

Site Supporter
Joined
Jan 28, 2012
Messages
5,127
Location
Montreal
Bike
2009 ST1300A9
Costco Canada sells 2L (4x500ml bottles) of 99% IPA for around $13
That's the best price I've seen. I'll have to find someone with a membership.

The last time I bought a 4L jug, admittedly several years ago, I think that it was something like 8 or 9 dollars. I still am curious as to why it has become so expensive, and why is it no longer in the hardware stores? Is there a alcohol shortage going on?
 
Top Bottom