Overview
The decision to fill the rivets was one of just visual finish as explained in the previous blog on filling the rivets.
Installation
The first method tried was body filler, it proved difficult to fill the rivets due to the air trapped inside the stem creating hydraulic lock, West Systems 105 could be inserted using a syringe, but lacked viscosity and this was an issue not to mention the need for small batches as both types have to be catalyzed before use. The excess of West Systems was hard to remove, and the builder considers this not an option.
Next, automotive spot putty, while easy to inject with the syringe, once cured it proved not to bond into the rivet opening and popped out easily when trimming, so the failure rate was high.
In desperation, a waterbased acrylic filler was tried [No-More Gaps family], and this worked well in all locations and proved to trim easily with a sharp blade, but the builder was worried about the temperature that the wings would reach in the dark camouflage.
It was decided to try Parfix Urethane Sealer Adhesive, this proved to work well in all respects and would be used again at the start.
The viscosity that gives it its useful properties creates an issue with the syringe keeping the needle on. Fitted the needle once as tightly as possible by winding it onto the syringe spigot and when not in use, inserted a length of safety wire and placed in the fridge. Filling the syringe was the other issue, drilled a 3 mm hole about halfway up the barrel, then filled to that hole before inserting the plunger as this allows the plunger to contact the filler providing a more accurate delivery.
Note: Prepare about four [4] syringes so if there are any issues replace it with a clean assembly
The urethane should be applied as outlined in the previous blog, then allowed to dry for a minimum of 24 hours; longer will be better. The reason is, while small in volume it's thick and therefore slow to cure.
Additionally, Urethane could be used on rivets that had small dishes or imperfections by applying a light coat onto the existing adhesive and allowing it to fully cure and dressing with the foam adhesive pads.
A word of warning, clean all material that is inadvertently applied as this material requires mechanical removal when cured, have a top-grade thinner available with clean rags when applying. It would be best to wear disposable gloves as it sticks to the skin just as aggressively and is difficult to remove - guilty OK.
Note: A Dremel Motor Tool and 1200 grit foam pads were purchased in bulk a long time ago but came into their own for this task. The best technique was to run the foam side across the dome of the rivet with the body of the chuck placed on the skin with a tool speed of 8-9 thousand rpm. This helped prevent excess pressure, do not go above 10000 rpm as the abrasive action can be destructive.
Tools
Mini Drill 1200 grit grey abrasive pads were used sourced from Allied Express but keep the rev's down as they can shift metal in the higher rev range
A Dremel motor tool with the accessory extension shaft is a must-have for this job, in fact, it has proved invaluable for many tasks.
Comment
Be careful about what you chose to do...!
Looking back it would now it would take about 40 to 50 additional hours to fill and prepare the rivets for painting but to get here this time took a lot, a lot longer, but that is the underlying story of this build,.
The finished look, however, made up somewhat for the lost time - just!
Oh, nice men have come with a new white coat, not my style though.
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