Dupont Vari-prime vs. epoxy primer - w some progress pics

[chgovfk]

Anyone have an opinion on either using Dupont Vari-primer or Epoxy primer on bare metal? - I hear Vari is an excellent corrossion inhibitor - but can be a little more costly - I'm at the point in my project where I'll be spraying it soon - I have a steel contractor who is going to CNC all of the metal plates for infill on the larger holes - some pic's of the progress.....

I first degreased everything - which isn't as easy as it looks - alot of sharp edges - which create alot of little cuts that burn along with the skin on my hands and arms from the chemicals .

 

[RacEoHolic330]

I'm not familiar with the vari-primer. What is it's base? Urethane? Epoxy will be a big pain to sand. Are you planning to apply filler on top of the primer and then prime everything again after sanding? If so, epoxy may not be such a big deal to seal everything.

 

[chgovfk]

Hey Scott - not sure - my old boss at the bodyshop swears by it - that doesn't make it a complete truth - he said to lay this down before any other primers or sealers / light coat of Vari-prime on all 'bare metal' - standard procedure at his shop - and his shop is one of the best - I'm asking him if it's 'before' you apply any filler or "after" - he said that after it's applied to the metal - you can build up all kinds of primer coats and sand after that "till my little hearts content"..... his condescending words - I was a wet sanding maniac back in the day -

VARIPRIME


® 625S™
SELF-ETCHING PRIMER
Copyright © 2007 DuPont. All rights reserved. The DuPont Oval Logo, DuPont™, The miracles of science™ and all trademarks listed herein
with ® or ™ are trademarks or registered trademarks of E.I. du Pont de Nemours and Company or its affiliates.
A DuPont OEM / Commercial Finishes Product
TYPE
Lead- and chromate-free, self-etching, non-sanding primer.
DESCRIPTION
Variprime

® 625S™ is a versatile product developed with self-etching
properties that allow it to be used over a variety of substrates, as well
as cured enamel topcoats. Variprime

® 625S™ delivers excellent
adhesion and superior corrosion resistance. It gets mixed 1:1 with
Variprime

® 614S™, Variprime® 616S™ or Variprime® 620S™ Converter
and does not require an induction period.
SUGGESTED USES
For use over properly prepared/cleaned substrates. Wash surface
with a mild detergent. Sand/featheredge substrate with P180 DA,
followed by P240 DA. Clean and degrease substrate to remove
contaminants.
NOT RECOMMENDED FOR

Immersion service
COMPATIBILITY WITH OTHER COATINGS

Can be used under all DuPont primer systems. For
optimum topcoat appearance, seal prior to
topcoating.
DRY FILM CHARACTERISTICS

Chemical Resistance VERY GOOD,
with appropriate topcoat

Humidity Resistance EXCELLENT

Weatherability EXCELLENT,
with appropriate topcoat
MAXIMUM SERVICE TEMPERATURE

150°F (65°C) in continuous or intermittent service
VOLUME SOLIDS

25.1% unactivated

12.9% RTS mixed 1:1 with Variprime® 616S™
WEIGHT SOLIDS

45.5% unactivated

23.6% RTS mixed 1:1 with Variprime® 616S™
WEIGHT PER GALLON

9.65 lbs/gal unactivated
SUGGESTED FILM THICKNESS

0.8– 1.2 mils dry film thickness
THEORETICAL COVERAGE PER GALLON

403 sq. ft./gal @ 1 mil DFT unactivated

207 sq. ft./gal @ 1 mil DFT mixed 1:1 with Variprime® 616S™
GLOSS

Flat
COLOR

Green-gray
FLASH POINT (CLOSED CUP)

Between 20- 73°F (-7 to 23°C)
SHELF LIFE

12 months minimum
APPLICATION SOLVENTS

None required. Up to 5% DuPont 8100S™ Acrylic Enamel
Retarder may be used in hot weather.
CLEANUP SOLVENTS


DuPont 3602S™ Thinner
ACTIVATION (MIX RATIO)
Mix 1 part Variprime

® 625S™ with one part Variprime® 614S™ Slow,
Variprime

® 616S™ Mid-temp or Variprime® 620S™ Fast Converter.
Mix thoroughly.
INDUCTION TIME

No induction time is required.
POT LIFE

3 days at 70°F (21°C)
ADDITIONAL COMMENTS

Allow 30 minutes flash prior to applying primer.

This product does not comply with Rule 66 (photochemically
reactive)

Variprime® is a non-sanding primer. However, if left to dry for
24 hours or more, sanding is required.
APPLICATION CONDITIONS
Do not apply if material, substrate or ambient temperature is less
than 50°F (10°C) or above 110°F (43°C). The substrate must be at
least 5°F (3°C) above the dew point. Relative humidity should be
below

 

[RacEoHolic330]

I see its an etching primer. Yea, you don't want to put etching primer on top of filler if you can help it. Etch primer is a great sealer for bare metal though. You may have to strip the entire bay down to bare metal if you plan to spray it with etch primer. Not entirely sure about that though.

 

[chgovfk]

Yeah - I'll have to talk to my old boss - I have a ways to go - b/c I plan to just 3M red scuff the firewall (no filler or metal in-fills there ) plus the underside and topside of the K member - but the rest ....see I thought I could just sand it all down to bare metal - weld the metal in fills in / sand that smooth ....apply the filler / - then start hitting it with a self etching primer. Maybe I'm off - let me see what the old man says.

 

[RacEoHolic330]

It all seems like preference. Some say don't apply filler over etch, some say don't apply etch over filler. Different strokes for different folks. I think the manufacturer of the product has a lot to do with it as well. The more you research about it, the more you'll get confused. I only used etch in the engine bay where I had large bare metal spots. I urethane primed my engine bay, which does not like bare metal, so that was why I needed the etch in spots.

http://www.autobody101.com/forums/viewtopic.php?f=5&t=17734

 

[chgovfk]

Thanks Scott - yea I guess I'll keep looking around / research and come to some conclusion - thanks for the link - I was always use to the fact that filler loves bare metal (although that was 20 yrs ago) - so ur right confusion confusion .......I have some time - hopefully I will have it prepped out this weekend.