What is the difference between singe stage epoxy primer and 2 stage epoxy primer - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Body - Exterior
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 05-30-2012, 04:59 PM
rusthater89's Avatar
Registered User
 
Last photo:
Join Date: Jul 2011
Location: new jersey
Posts: 208
Wiki Edits: 0

Thanks: 4
Thanked 2 Times in 2 Posts
What is the difference between singe stage epoxy primer and 2 stage epoxy primer

I was on the Summit Racing site and I noticed they have a single stage epoxy primer and a higher priced 2 stage epoxy primer. What is the difference between them?

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 05-30-2012, 05:32 PM
Registered User
 

Last journal entry: Paint
Last photo:
Join Date: Sep 2010
Location: USA
Posts: 797
Wiki Edits: 0

Thanks: 0
Thanked 9 Times in 9 Posts
All I have to say is watch out what you are buying. I made the mistake of buying the more expensive epoxy primer on Ebay. I assumed it came with the hardner the way it was worded. I payed more on Ebay than what Summit sells it for. I then had pay extra to get the hardner. Summit sells 2 different brands of epoxy primer. One brand uses 3 parts epoxy to 1 part hardner and the other brand uses a 50/50 mix of epoxy primer and hardner. The only reason I bought the epoxy primer on Ebay is because I needed it and they did not sell epoxy primer at the local paint supply store. The more expensive epoxy primer is real thick and should be reduced. You will get orange peel in the primer if it's not reduced.

Last edited by V8&4spd; 05-30-2012 at 05:38 PM.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 05-30-2012, 05:45 PM
MARTINSR's Avatar
Brian Martin,Freelance adviser
 
Last photo:
Join Date: Jun 2004
Location: San francisco bay area
Age: 55
Posts: 13,006
Wiki Edits: 0

Thanks: 708
Thanked 1,076 Times in 959 Posts
There is no such thing as two "stage" or one "stage" epoxy. There is a two "part" or one "part". Commonly called "1K" or "2K". The name came from Europe with it meaning "1 component" and "2 components". Yes I know Component starts with a C not a K, it's Europe I don't know. Which means with or without hardener., two part being with a hardener and one part being without. And the funny thing is a "one part" epoxy doesn't exist so they are throwing the name "epoxy" around when that isn't even what it is.

You want a REAL epoxy which is a two part and you want to follow the tech sheet given by the manufacturer.

Brian

Here's a "Basics" on paint technology's.

"Basics of Basics" Paint technology.
By Brian Martin

There are many different types (or more correctly, technologies) of products you can use in the restoration or repair of your vehicle. Some have a variety of uses while others are very limited with only a few of specific uses. Proper choice of products can help you get the job done faster and/or help with the longevity of the repair.
Let’s start with some basic definitions. I couldn’t possibly know every paint manufactures terminology or product use. These are generalities and should be used as a guide only to then read the tech sheets of the products you are choose for proper use. These tech sheets can be found at the jobber and are given away free. Or most manufactures have them on line, USE THEM. They are a wealth of information and can save you many headaches. You don’t need to read every word in the mind numbing text, they usually have a “product at a glance” or something like that will cut to the chase and give you what you need.

Basic terminologies;

“Solvent” is a generic term and refers to any “reducer”, “thinner” that is used to reduce the viscosity (“thickness”) of a product to aid in spraying or applying. It could be acetone, lacquer thinner, urethane reducer, a special “basecoat” reducer, water, alcohol, etc. These solvents ARE NOT INTERCHANGEABLE; each product MUST be used with the specific solvent recommended by the manufacture.
“Etch primer” an acid containing primer.
“Primer” a product that can be applied to bare metal
“Surfacer” (or “primer surfacer”) A primer that has “body” or solids and is used to fill imperfections and provide a film thickness to sand or block a surface to a smooth base for paint.
“Sealer” a non-sanding product that is applied prior to painting.
“Primer-sealer” A sealer that can be applied over bare metal and then top coated without sanding.
“Flash time” the time you allow the solvents to evaporate out of the film you have applied.

Basic technologies;
“Single component” or RTS (Ready To Spray). This is a product that uses no additional components. Just pour it from the can into your gun and shoot. Examples are: Some plastic adhesion promoters and primers and even some top coats like vinyl colors.

“1K” This is a product that uses no hardener, catalyst, activator, etc. It may have an added solvent, but no hardener or activating reducer. 1K products like RTS dry with the evaporation of solvents and are soluble, meaning that they are could be wiped off with a rag soaked with lacquer thinner. They could in THEORY be scraped off and put in a can with solvent and stirred back to a sprayable condition. Of course ALL RTS products are 1K. Examples: All lacquer products, some synthetic enamel products, and some acrylic enamel products. Because of the low VOC regulations the 1K product options are getting scarce, with most limited to “specialty products” like adhesion promoters.

“2K” or “Two component” is any product that uses a hardener, activator, catalyst, etc. It may or may not use a third component in the form of a solvent. 2K products don’t “dry” like a 1K. The 2K product “cures” by molecules linking together to form a whole new compound. Most high quality 2Ks are insoluble after a full cure and will not soften when exposed to solvents like thinners or gas. Examples are urethane under coats and top coats. Epoxies, ISO free products that use a hardener, etc.

Basic tip, ALL 2K products should be mixed as accurately as possible. As a rule 2K products need a minimum of 55 degrees to cure with an ideal minimum of 65 degrees. MIX THEM AS DESCRIBED BY THE MANUFACTURE. They have spent hundreds of thousands, possibly millions of dollars developing the product, they WANT it to work as BEST it can. Do as they say, don’t become a “Junior Chemist”.

Types of products and their uses;

Etch primers (some are 2K)

“Wash” or “Vinyl wash” are for bare metal applications for the ultimate in adhesion and corrosion protection. They are very low in solids with next to zero filling qualities. Some are even semi transparent. They are usually not to be top coated with paint. You apply them to aid in adhesion and corrosion protection under other undercoats such as epoxy or urethane primers.
Benefits:
- Very thin, keeps down film build
- Cost effective
- Fast application
- Non-sanding
- Super high corrosion protection.

Disadvantages:
- Some have a very small re-coat window


“Etch primer” (some are 2K)

Typical “etch primers” have much more solids and body than “wash” primers. They are more forgiving than “wash” primers, one thing being a much longer re-coat window. They are basically used to aid in adhesion and corrosion protection as with “wash” primer. You would choose “typical” etch over “wash” if you have some paint or plastic filler as a substrate along with the bare metal. Some brands have a recommendation to apply top coats over it also. This could be very useful in a money saving or time saving is important.

Benefits:
- Easy to apply, smooth, easy to sand
- Some can be applied over plastic filler (not that you need it over the plastic filler, but if you have some, it is nice to not have to go around it)
- Some can be top coated, which can be a big time and money saver.
- VERY cost effective

Disadvantages:
- Added product to buy and apply.


IMPORTANT basic! If you have used ANY metal treatment or “conditioner” read tech sheets carefully for compatibility . The acid in the metal “treatment” or “conditioner” can attack the acid in etch primers and it can LOOSE adhesion from the metal!

Urethane primer (2K) Urethane primer is the most common primer used in auto body and restoration by far. It has good solids and fills well. It is easy to sand and can provide you with a perfect body when blocked properly. Care should be taken when applying it as to not use too much. It can shrink when applied too heavy. It is the best all around primer for applying over plastic body filler and for surfacing your work. If used properly it provides the proper film thickness under top coats and is the perfect substrate for bs/ss and SS.

Benefits:
- Easy to apply, and sand.
- Applies smooth.
- Fills well with minimum of shrinkage

Disadvantages:
- Contains Isocyanates.
- Should always use an etch primer under it.


Epoxy primer (2K)

Epoxy is a good corrosion fighter. It is has a very sticky resin and will provide good adhesion to MOST substrates. It typically has poor filling and sanding qualities (that sticky resin makes sanding difficult) . It is ideal for use as a “primer/sealer” on bare metal that requires no surfacing.
Perfect for frames and components, radiator supports, items that are sandblasted and you only need to prime and paint. You use it as a non-sanding “primer/sealer” and then paint right over it.

Benefits:
- Good chip resistance (it isn’t as hard as a urethane)
- Perfect for a “primer/sealer” over bare metal.
- Etch primers can be skipped because of its excellent adhesion and corrosion properties.
- Provides good base under plastic body fillers (skip the etch if you plan on using plastic filler over epoxy)
- Epoxy has no isocyanates .

Disadvantages:
- Poor sanding qualities
- Poor filling


Polyester primer (2K)

Polyester is a very specialized primer used in very small amount in most shops across the country. But when it is needed, it does a job like no other. Polyester has a huge solids content and will fill 80 grit scratches in one coat or 36 grit in two or three! Urethane for instance provides about ½ or ¾ mils per coat while polyester can give you as much as 4 to 6! Because of it’s high solids, it shrinks very little. It is basically like spraying polyester putty. Look for a manufacture that has a recommendation to apply etch primer under it. I see NO reason to use polyester on a straight panel. It is for use only when you need some serious filling and surfacing.

Benefits:
- VERY high filling
- Low cost

Disadvantages:
- Very high texture
- Harder to sand than a urethane
- Possible need to purchase a large gun to shoot it.

“ISO FREE” (2K)

“ISO FREE” is a urethane type primer but without the harmful isocyanates that a urethane contains.
The problem is ALL refinish products should be used with the same care and concern for your health and others. ISO FREE is like “low tar” cigarettes, don’t kid your self, it is still VARY harmful.

Benefits:
- Isocyanate free
- Smooth, easy sanding
- Good filling
Disadvantages:
- You need an etch over bare metal before it.

Basic tips… Etch primers can be skipped on spots of bare metal smaller than a dime or so when using all primers listed.
Most “quality” 2K primers need NO sealer before top coating with bc/cc or SS when applied properly.


Sealers

All RTS or 1K sealers should be reserved to VERY low end jobs to save money. They do NOT offer the benefits of a 2k, PERIOD.

Reasons to use a sealer:

- Makes up for “some” poor preparation
- Provides a uniform color for better coverage when you apply paint.
- Helps with providing a uniform substrate for paint.
- Helps provide a better substrate when painting over a 1K primer.
- Can Help with “covering” poor prior repairs

Under collision repair conditions a shop may use sealers on every job as an “insurance” protection against problems. In a restoration environment where complete panels are primed with a 2K there really is no need to use them.
If you have chosen to use a sealer there now are a few more choices to make. First, you need to decide what kind of sealer to use. As I mentioned in the beginning, RTS or 1k could be used to save money. Why put a 1K sealer over your 2K primer (I hope you are using a 2K primer) then apply a 2K top coat? It is like the old saying, “It’s only as strong as it’s weakest link”. If you use a 1K sealer in this fashion it is like replacing a link in your tow chain with a nylon tie!

With 2K there are a few options, epoxy and urethane being the most popular. I don’t feel that there is a huge difference in the two as far as how they apply or work. Epoxy is more forgiving with sensitive substrates. It really comes down to what you feel more comfortable with. The epoxy has no isos so that would be one reason to choose it.
Now that you have decided what sealer to use you have to decide on what application.
Most sealers give you the option of a “wet on wet” (or very close to it) or a full “barrier coat” application.
The difference being with “wet on wet” the sealer is applied and then allowed a short flash time before the basecoat or SS is applied. A “barrier coat” is where the sealer is applied, then allowed to cure or at the very least to totally flash. This allows the sealer to become a barrier so the solvents from the color coat can’t penetrate it and attack the substrate.

The barrier coat procedure allows for he sealer to do MUCH more of what you choose to use a sealer for in the first place. The choice is made taking into account a few factors. How sensitive is the substrate? Or, how aggressive are the solvents in the color coat that you are applying? If it is very hot weather and you are using a slow solvent in the color coat to help it lay out, you may choose to use a sealer because you know that the substrate is sensitive and the slow solvent will attack it.

Well, that is about it for the basics, have fun!

Last edited by MARTINSR; 05-30-2012 at 05:51 PM.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 05-30-2012, 05:51 PM
Registered User
 

Last journal entry: Paint
Last photo:
Join Date: Sep 2010
Location: USA
Posts: 797
Wiki Edits: 0

Thanks: 0
Thanked 9 Times in 9 Posts
I was told by the local paint supply store that epoxy primer was old school. That was the first time I heard that one. The more exspensive Summit epoxy primer has a gloss to it if you don't use reducer. I have some that has been on for about 6 months now and it has not dulled down yet.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 05-31-2012, 12:15 AM
put up or shut up
 

Last journal entry: saying goodbye to the beast
Last photo:
Join Date: Apr 2011
Location: Antelope, Ca
Posts: 2,005
Wiki Edits: 0

Thanks: 556
Thanked 217 Times in 196 Posts
Quote:
Originally Posted by V8&4spd
I was told by the local paint supply store that epoxy primer was old school. That was the first time I heard that one. The more exspensive Summit epoxy primer has a gloss to it if you don't use reducer. I have some that has been on for about 6 months now and it has not dulled down yet.
what's old school about it, did he say? I think epoxy primer is great
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 05-31-2012, 05:02 AM
jcclark's Avatar
The Penny Pincher
 

Last journal entry: Hanging Bumpers
Last photo:
Join Date: Dec 2004
Location: Louisville, Ky. U.S.A.
Age: 61
Posts: 1,869
Wiki Edits: 0

Thanks: 4
Thanked 18 Times in 15 Posts
He's got it backwards, etch primer is "old school"
epoxy is the newer better way.
Epoxy primer is the only product that is truely waterproof.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 05-31-2012, 06:54 AM
rusthater89's Avatar
Registered User
 
Last photo:
Join Date: Jul 2011
Location: new jersey
Posts: 208
Wiki Edits: 0

Thanks: 4
Thanked 2 Times in 2 Posts
Yea, I figured that there being one stage and two stage epoxy primers as a funny thing. I'm glad I cleared it up. I probably be using the cheaper Summit epoxy primer since that is what I been using and it looks good. Plus I barely have any money.

Also I never heard from anyone saying that epoxy primer was inferior. What did that paint guy mention is the latest technology then?
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 05-31-2012, 07:30 AM
MARTINSR's Avatar
Brian Martin,Freelance adviser
 
Last photo:
Join Date: Jun 2004
Location: San francisco bay area
Age: 55
Posts: 13,006
Wiki Edits: 0

Thanks: 708
Thanked 1,076 Times in 959 Posts
I don't know when epoxy came around but I remember very well that back in the eighties epoxy WAS "old school". It was looked down on as urethanes had made big jumps in quality and NO ONE was using epoxies at least around my area.

Epoxys have taken on a new life for a number of reasons but they were "out" thirty years ago.

Brian
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 05-31-2012, 07:38 AM
rusthater89's Avatar
Registered User
 
Last photo:
Join Date: Jul 2011
Location: new jersey
Posts: 208
Wiki Edits: 0

Thanks: 4
Thanked 2 Times in 2 Posts
Quote:
Originally Posted by MARTINSR
I don't know when epoxy came around but I remember very well that back in the eighties epoxy WAS "old school". It was looked down on as urethanes had made big jumps in quality and NO ONE was using epoxies at least around my area.

Epoxys have taken on a new life for a number of reasons but they were "out" thirty years ago.

Brian
Wow, really? Were the epoxy primers 30 years ago inferior to our current epoxy primers today.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 05-31-2012, 11:06 AM
jcclark's Avatar
The Penny Pincher
 

Last journal entry: Hanging Bumpers
Last photo:
Join Date: Dec 2004
Location: Louisville, Ky. U.S.A.
Age: 61
Posts: 1,869
Wiki Edits: 0

Thanks: 4
Thanked 18 Times in 15 Posts
If there's someting better for bare metal I want to know
what it is.

Also, keep in mind, 30 yrs ago "Epoxy" was just a generic
term for anything requireing a "catalyst" or "activator"
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 05-31-2012, 02:24 PM
Registered User
 

Last journal entry: Paint
Last photo:
Join Date: Sep 2010
Location: USA
Posts: 797
Wiki Edits: 0

Thanks: 0
Thanked 9 Times in 9 Posts
I think they were calling epoxy primer old school because they make a urethane primer that goes on bare metal. I have never tried it because I am use to using epoxy primer on bare metal. They also make some paint that does not need a primer. Epoxy primer is unavalble in some states. I tried to figure out who made the more exspensive Summit epoxy primer when I found out it did not come with the hardner. I went to the local paint store to see if they sold a hardner that would work. They got mad at me for buying the epoxy primer on line, I told them I needed it and they did not sell it. They made some calls and could not figure it by the mixing ratio. You will have left over hardner with the more exspensive epoxy primer because that is the way they sell it. It says to use a urethane grade reducer so it might not need the brand Summit sells.
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 05-31-2012, 04:51 PM
Registered User
 

Last journal entry: Paint
Last photo:
Join Date: Sep 2010
Location: USA
Posts: 797
Wiki Edits: 0

Thanks: 0
Thanked 9 Times in 9 Posts
These hinges were done with what Summit refers to as 2 stage epoxy primer it was unreduced.
Attached Thumbnails
Click image for larger version

Name:	006.JPG
Views:	167
Size:	322.1 KB
ID:	65739  
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 05-31-2012, 05:51 PM
rusthater89's Avatar
Registered User
 
Last photo:
Join Date: Jul 2011
Location: new jersey
Posts: 208
Wiki Edits: 0

Thanks: 4
Thanked 2 Times in 2 Posts
Quote:
Originally Posted by V8&4spd
These hinges were done with what Summit refers to as 2 stage epoxy primer it was unreduced.
That don't look much different then the cheaper one. The cheaper version also has a similar amount of shine to it. I'll try to post a pic of something I did later.
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 05-31-2012, 06:13 PM
Registered User
 

Last journal entry: Paint
Last photo:
Join Date: Sep 2010
Location: USA
Posts: 797
Wiki Edits: 0

Thanks: 0
Thanked 9 Times in 9 Posts
Quote:
Originally Posted by rusthater89
That don't look much different then the cheaper one. The cheaper version also has a similar amount of shine to it. I'll try to post a pic of something I did later.
I thought I was getting the cheaper epoxy primer. I didn't know they had 2 different brands. I would have never spent what it ended up costing me in the end. I didn't need that much primer. I was in hurry and should have paid more attention to the ad. It was non returnable after I pressed buy it now. This is the 3rd different brand of epoxy primer I have used, all the brands worked for what I needed it for. I was going to try out the paint they sell at Summit, not anymore. I want to know what brand I am buying, I know Summit can't be making the paint.
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 05-31-2012, 07:44 PM
rusthater89's Avatar
Registered User
 
Last photo:
Join Date: Jul 2011
Location: new jersey
Posts: 208
Wiki Edits: 0

Thanks: 4
Thanked 2 Times in 2 Posts
Quote:
Originally Posted by V8&4spd
I thought I was getting the cheaper epoxy primer. I didn't know they had 2 different brands. I would have never spent what it ended up costing me in the end. I didn't need that much primer. I was in hurry and should have paid more attention to the ad. It was non returnable after I pressed buy it now. This is the 3rd different brand of epoxy primer I have used, all the brands worked for what I needed it for. I was going to try out the paint they sell at Summit, not anymore. I want to know what brand I am buying, I know Summit can't be making the paint.
Yea Summit has a cheaper one where you mix 1:1 with epoxy and catalyst. After shipping it costs me $97. Perfect for me since I am poor.
Reply With Quote Quick reply to this message

Recent Body - Exterior posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
HOK Ko-Seal Primer Sealer vs Epoxy Primer 67Elcamino Body - Exterior 0 02-02-2012 11:34 PM
Flash rust OK under epoxy? SPI epoxy primer, Transtar 6131, or PPG Shop Line? off2wildblue Body - Exterior 2 07-29-2010 08:53 PM
Epoxy Primer & 2K Urethane Primer acquadigio79 Body - Exterior 17 08-15-2009 04:07 PM
Epoxy Sealer-Primer With 2K Build Primer on top kilgorq Body - Exterior 4 04-29-2008 04:30 PM
can i spray epoxy primer over etching primer without sanding? wickiewicked240z Body - Exterior 1 08-29-2006 09:07 PM


All times are GMT -6. The time now is 07:25 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.