Jotamastic 80/87

[Championship White]

Has anyone used Jotamastic and Lechlar or other iso-containing epoxy primer?

Both are 2 pack but Jota is iso-free and only needs a charcoal mask, I'll be getting some sort of air-fed set-up in the future but whilst I plan and save for it I'd like to know if the Jota is just as good as it's iso-containing pals like the Lechlar alternative so I can start chopping, welding and epoxy'ing as I go.

So the question: Is 2 pack non-isocyanate epoxy primer as effective as 2 pack isocyanate containing epoxy primer?

 

[MG David]

I guess you are painting a car. Are you painting the underside and or internal surfaces?

If so Jotamastic will do a good job. I used Rust Busters 121 Epoxymastic but when I finished it I tried Jotamastic 80 because it comes in 4.6L at a time for the price of 2L Rust Buster 121 Epoxymastic.

Both give you a heavy tough paint film. If you are only going to use small quantities at a time 121 might be easier to use as it has a 1:1 mix ratio where as Jota is 7:1.

"Normal" epoxy primer like applied from a spray gun will give a much better finish and so should be used on outer panels.

The Jotamastic I use is 80 I have not tried 87. 80 is thick enough for me.

 

[Championship White]

Yep it's for a car and will be a bare-shell job replacing arches and seam welding the body. Why is the Jota less suitable for the visible paintwork?

 

[MG David]

Jota is a tough heavy paint film which when put on by brush does not provide the even uniform coat that you want from a primer underneath your colour coats. I think if you use it on the outer face of the upper panels you will end up using alot of high build to get a fine surface.

However, its resistance to abrasion and salt water makes it ideal for the underside and inside wheel arches.

 

[steveo3002]

goes on ok with a spray gun ..does take a while to harden though

 

[Championship White]

I'll be using a 2.0 gun to apply it so will it be ok to apply on the upper panels and what treatment should I give it before it full hardens to prep it for 2-pack HB?

 

[vdubz]

It won't need any treatment(sanding), If your spraying the epoxy, just let it flash and then put your high build primer straight over it. This way you will have a better bond between your epoxy and high build and it will save time.

 

[steveo3002]

take note they do winter and summer hardner on the jota ...

 

[Championship White]

Cheers for the info. guys, I also found on another thread that one problem someone had was the lack of flow with the Jota but another user posted that it was fine when thinned to the ideal amount so I should be fine as long as I give it a test first and make sure its properly thinned.

 

[Chipper]

Great for undersides, wouldn't use it topside though. Sprays fine, doesn't take a lot of thinners to change it from syrup to sprayable.

 

[Championship White]

Why is that chipper? Ease of use or actual suitability?

I'm happy to work harder to achieve the same finish at the end as use Lechlar etc. epoxy, but if it's impossible from the beginning I won't bother. It's only be on the bare metal at the rear arches where it will be used as opposed to a full bare-metal respray of the car. It's a 92-95 Civic which I'm learning to weld and use 2k products (when I get the gear) on.

 

[MG David]

When it comes to spraying their TDS says to use airless.
http://www.jotun.com/jotun/paints/2...6135c6743fb48a56c125729f003f9223!OpenDocument

Does anyone know why?

 

[Chipper]

It's very hard to sand, it doesn't flow out, not sure wet-on-wet would work so well with it, with normal 2k primers or colour. It sprays fine out of my conventional primer gun with 2.0 setup, I use 2k thinners though they do their own one.
An automotive epoxy is a completely different animal, flows, lays down nicely, easy to sand, can go wet-wet with 2k colour etc.

No doubt you can use Jotun and others on top, myself I'd much rather use the better thing i.e. automotive epoxy from the start.

 

[Championship White]

Ok, I'll just do all the underside work with it and wait do the outer arches until the end when I've got a breathing set-up.

Cheers all

 

[jaykay]

i've been watching this thread.
all i will say is i had a rep trying to sell me on jotun paints.at the time i was using international.
not putting jotun down,but stayed with international.
it did not even come near.

 

[steveo3002]

jay..what are/were you using it on ?

please share why you like international

 

[Chipper]

Same here, any name or code etc, always good to learn what's what out there.

 

[Championship White]

Is it non-iso? And what makes it better than Jota in your opinion?

All the links I could find for it were horrendously expensive - it's 4 times more expensive at least than Jota from what I can see so I'd hope it's 4 times as good

 

[jaykay]

i was using it to spray cherrypickers.was using it hotpot.
it was 15 yrs ago. i think it was iternational222

 

[Championship White]

Can't find it, but would have thought during 15 years Jota would have changed their paint 'ingredients' somewhat so I'm not sure if today's product would be the same as 15 years prior. But then I'm no paint manufacturing expert