Model Boat Mayhem - Forum

Technical, Techniques, Hints, and Tips => Painting, Finishing and Care. => Topic started by: tizdaz on December 19, 2017, 03:43:02 AM

Title: Isopon Primer?
Post by: tizdaz on December 19, 2017, 03:43:02 AM
Hi guys,


is this stuff good to use as a primer (on gel coated fibreglass) Isopon Multipurpose Primer (http://www.halfords.com/motoring/paints-body-repair/primer/isopon-multipurpose-primer-aerosol-450ml)? Obviously i will sand areas 1st to key so it sticks well but just not sure if this is decent primer as its only 1 more than the halfords stuff.


Or is this best Halfords High Builder Primer (http://www.halfords.com/motoring/paints-body-repair/primer/halfords-high-build-primer-500ml) ?


& what spray cans are best to use?


Thanks in advance :)
Title: Re: Isopon Primer?
Post by: Brian60 on December 19, 2017, 07:23:15 AM
Any of them, they are made for the purpose.

What you do need to do is prep the surface properly, its no good sanding it, the paint won't grip.

The process is thus....

Wash the surface with clean soapy water and rags, allow to dry.

Wipe surface vigorously with a cloth ligthtly damped with acetone, allow to air dry

Wipe surface in one direction only full length to other end with a clean cloth lightly damped with acetone. If you are not happy using acetone use alcohol. You can also use what is referred to as tack rag or tack pads at this stage, they are squares of material impregnated with a chemical agent that is tacky (obviously) and picks up any residual surface crap.

Sand with 240 grit paper or a scotchpad to key surface. Wipe over once more.

Prime.

The reason for this is that the surface of fresh grp will be contaminated with the waxes/release agents used to get it out of the mould when made. You can't see them but they are there. Using a sandpaper or scotchpad without first cleaning just rubs these waxes into the grain and key marks made by the paper where they sit and until you paint. Then you find out your paint won't stick to the surface in places and peels away. This is the point where you curse and blame the paint for being crap, when in fact it is attention to the preparation that is at fault. Don't forget you also need a warm environment to spray even rattle cans, around 21c 70f is required, not outside at this time of the year!
Title: Re: Isopon Primer?
Post by: Stavros on December 19, 2017, 09:41:12 AM
Panel wipe will get the surface clean ready for paint and really you need to use this after rubbing down prior to using any paint....personally i would use halfords high build primer.......or if you want....pop it up to mine and ill spray 2 pack primer on it for you free of charge


Dave
Title: Re: Isopon Primer?
Post by: tizdaz on December 19, 2017, 02:43:16 PM
Panel wipe will get the surface clean ready for paint and really you need to use this after rubbing down prior to using any paint....personally i would use halfords high build primer.......or if you want....pop it up to mine and ill spray 2 pack primer on it for you free of charge


Dave


Cheers for info guys, & thanks alot Dave, much appreciated! Think i might take you up on that offer as i don't want to balls it up!! Once i get the prop shaft fitted & deck in place will arrange to come visit you, thanks again :)
Title: Re: Isopon Primer?
Post by: Klunk on December 19, 2017, 05:55:36 PM

Cheers for info guys, & thanks alot Dave, much appreciated! Think i might take you up on that offer as i don't want to balls it up!! Once i get the prop shaft fitted & deck in place will arrange to come visit you, thanks again :)
Stavros in a Minion suit........beggars belief