repaint question??

[crosser]

im repainting my little boat and ive gone mostly back to metal...   will need a bit of filler here and there..  question is do i fill on bare metal or red oxide first then fill?    thanks

[Chewbacka]

1 hour ago, crosser said:

im repainting my little boat and ive gone mostly back to metal...   will need a bit of filler here and there..  question is do i fill on bare metal or red oxide first then fill?    thanks

I have always believed that polyester filler sticks better directly to steel.  

[Tony Brooks]

Except polyester filler is porous so any damage to the paint film is likely to lead to rusting under the filler and eventually the filler will get pushed away from the steel and split.

 

I would use epoxy filler from choice. On the boat I have taken to very course abrasive scratching, then Vactan or primer, fine abrade so as not to go through the coating, de-dust and de-grease and then fill.

 

[dmr]

The car body people always say filler first but I always do the primer first and have never had and filler failures. I use Bondaprimer for small repairs and it really sticks to the steel so I am happy putting filler over it. Get to bare steel then primer, no need to use a rust treatment if you have removed the rust.

 

...............Dave

[Tony Brooks]

1 minute ago, dmr said:

The car body people always say filler first but I always do the primer first and have never had and filler failures. I use Bondaprimer for small repairs and it really sticks to the steel so I am happy putting filler over it. Get to bare steel then primer, no need to use a rust treatment if you have removed the rust.

 

...............Dave

Agreed but often canal side total removal is not possible unless you grind away all the rust pits so rust treatment seems a good idea to sort out any rust hiding in pits and scratches.

[crosser]

thanks all...  ive used fertan on the rust after grinding it back then i will primer with red oxide and then fill any pitting then sand and primer over the filled bits then top coats...