Is MEK Peroxide the same as MEKP?

It’s just about warm enough around here to attempt the gel repairs on my QCC 400X and I went to the hardware store to pick up some MEKP hardener as Phil at QCC suggested back in January and they didn’t have any hardener labelled as MEKP, but did have the MEK Peroxide in the Bondo brand. I assume that MEKP and MEK Peroxide are the same, but wanted to verify that before using it for the gel repair.




methyl ethyl ketone peroxide
MEKP is methyl ethyl ketone peroxide, which is the catalyst for polyester resin.

MEK is methyl ethyl ketone.

These two are quite different. MEK will not work as a catalyst for resin.

Careful, you’ll put your eye out !

So, are MEKP and MEK Peroxide the same?
I couldn’t tell from your response.

Are you agreeing or disagreeing with jbv?

MEKP = MEK Peroxide
They both stand for

methyl ethyl ketone peroxide

Nasty stuff - cancer in a bottle, get it in your eyes and you’ll follow a dog. Use respirator, eye protection, gloves, etc.

MEKP = Mean Stuff

Methyl ethyl ketone peroxide (MEKP)

Actually exists in several molecular variations in standard usage.

Toxic, colorless, explosive, sensitive to shock,

a severe skin irritant and can cause progressive corrosive damage or blindness.

I use this stuff outside ONLY, wearing eye-protection and a respirator.

If you do not have these quality items – GET THEM FIRST.

Interesting reading:

Do I have an alternative option
for the QCC gel coat? I have no plans to buy a respirator for this job.

If the MEKP is really that nasty, I may just use duct tape until I can afford to ship the boat to QCC for repair.

Or duct tape your nose when using it
(get 'er fixed, Mr. Yanoer, and let’s paddle. If for any reason I an free end of June, paddle IL River with Donna5764 and I. I’m still checking my calendar).

Yanoer … as always , Call me if you
want an answer to your questions from a professional.

Did I miss something?
I thought your boat had a split seam- gel won’t fix that.

For the MEKP, you should be fine working outside or in a garage with good air circulation. When I was at QCC they had all the doors open and the fumes were still overpowering.

Yeah, still scratching my head
why they told you what they did Yanoer … really isn’t right + just making a mess that they then have to clean out.

Two problems I recall?
Both a split seam and some seriously cracked up gel coat, if I remember right.

Get a respirator
It’s a good investment to have one around, as you should use it whenever you’re working with strong solvents and chemicals. That includes when you’re gluing Minicel foam into your boat with contact cement or using sealants on bulkheads and such. Additionally, a good respirator will allow you to switch from chemical cartridges to dust filters for use when you’re sanding, working on your car’s brakes and similar activities.

If you’re not willing to invest in the basic safety equipment, leave the gelcoat work to the pros.

Recommendations for respirator & filter
for gel & resin work?

One potential problem I have with wearing respirators is getting a good fit. At work I ended up having to use a full face because the standard units that most of the other employees used wouldn’t seal tight on my face and, therefore, weren’t effective.

That also means that I’d have to shave my beard off again in order to wear respirators again.

I hopefully won’t have much gel or resin work to do - it’s not something I enjoy. I am very sensitive to many chemicals - including many that don’t seem to bother other people - so maybe a respirator might be a handy item to have around and make some dreaded chores less stressful.

I suspect that a well-fitting respirator and appropriate cartridges may end up costing almost as much as shipping the boat to QCC for repair.

3M, AO Safety…
…and other companies make respirators. Check your local hardware store(s) or home center(s) and buy it there, so you’ll be able to try it on and get replacement cartridges when you need them.