Fibreglass revision off – leaving a nice matt surface with very good surface texture, giving a good mechanical bond ideal for further layups or other ongoing processes.
6 Practical examples
To ensure a full understanding of the use of the various materials and for practical experience, John got me to produce a sheet of fibreglass, cutting out two UNI cloths, preparing the correct mixture and quantity of resin and laying them up. To help remove it from the working surface we laid it up on a cling film backing, and used peel-ply on the final surface. We then progressed onto building a flat structural plate and a curved shape using BID.
7 Repairing Tim’s spats
Once we had finished the revision of the basics of fibreglassing, we continued to repair Tim’s spats which, after the brush up and practice we’d had, proved to be pleasantly straightforward.
“ Strangely, we were
not working at the same speed as the previous day – it had nothing to do with a very convivial evening, you’ll understand…”
We cleaned up the damaged area with a Dremel and removed a previous repair that had been made with polyester resin and had clearly not adhered well to the epoxy resined spat. We then set about following the same procedures as described above for the repairs. It worked a treat and was done surprisingly quickly. While waiting for the glass to harden we would inevitably have a coffee and cake break, where serious philosophising took place – such as the discussion on why, when your wife makes a wonderful looking cake do you get told off for eating it! Surely the point of a warm and inviting cake is to eat it… The following morning was spent cleaning up the spats and rubbing down to make the job look good and inspect it for final quality and strength. Strangely, we were not working at the same speed as the previous day – it had nothing to do with a very convivial evening, you’ll understand… John explained how to identify a crack on a finished surface like a wing or tailplane and what type of repair would then be required. By marking it with a quickdrying, fade-resistant Sharpie felt tip pen, if on grounding down the gelcoat the ink has gone then the crack was only in the surface finishing gel coat, but if it bleeds into the fibreglass structure then a fibreglass repair is needed. At the end of John’s mini-course I left with three different examples of fibreglass work that I had fabricated and Tim left with repaired spats, which will last him for another season or two, but most importantly a whole lot of renewed knowledge and some great memories. All in all, it was valuable revision with a good practical purpose – and great fun, which had its origins in three good friends’ original meeting many years ago at our local Strut – thanks to the LAA. ■ Left A happy Tim finishing off a spat before repainting and refitting it to his Europa.
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