This may work out to be a long winded explanation of what's going on, but I'll try get to the point.

7-9 years ago I got my frigate hull. I dually prepped and painted the hull in this manner.

1,Rubbed hull down with 600 grit wet & dry (with water).

2,Washed hull with warm soapy water (allowed to air dry).

3,Rubbed again with wet & dry 1000 grit (till a perfect smooth painting surface was accomplished).

4,Washed again with soapy water (left to air dry).

5,Because of problems in the past....washed with paint thinners 4-5 times (basically every time the hull had been handled to remove any grease from hands).

6,Painted hull using airbrush (7 or 8 coats per colour until even deep looking coverage achieved, giving at least 2-3 days between coats).

7,Noticed some cracking on underside of hull.

8,Rubbed back to bear hull.

9,Repeated steps 4,5,6. Half way through step 6 airbrush packed in and splattered paint all over hull. Rubbed back with 1000 grit to get flat surface.

10,Mixed paint with thinners for brush painting, completed hull colours.

At this point work, house moves, children came along and the hull was put into loft for storage.

11,7 years later, start building again. No cracking on hull, but hull twisted whilst in storage.

12,New bulkheads added twist eventually sorted, clamp marks all over paint.

13,Rubbed back to bear hull, brush paintinted the first couple of coats (still no airbrush).

14,Hull put aside during two more house moves.

15,Hull rubbed back a little. Steps 4 and 5 repeated again (airbrush bought).

16,Spray painted hull at the weekend Crackling back.

17,Hull rubbed back to the first couple of coats.

18,Just out of curiosity hull brush painted yesterday and today with the exact same paint and mixed proportions of thinners and paint (the paint that was left in jar from weekend).

**What do you know....there is no crackling of paint.** Can anyone explain to me what's happening, because I haven't got a clue

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