Monday, May 18, 2009

Skin Graft . . .

An early morning start required as the location for the "skin graft" was at the other end of Perth about 60 km from where I am.
Never the less the "house" was successfully off the truck by about 8:30 and ready to go.























The roof was going on first so preparation began by sanding all the roof beams and then washing down with the appropriate solvent.


















The previously prepared skin was trimmed to size and then lifted onto the roof for a "dry fit". ie No glue at this point.























After it was determined that all was well (ie the correct size and shape) each end was then lifted and glue applied.


















In addition a glue / sealer was applied to all inside beam and sheet joints.


















So when viewed from outside it all looked lovely and flat and shiny . . .










































Some heavy sheets of ply were then lifted on top and distributed to keep even pressure over all.

The end was going on next so the sheet was prepared by cutting to size, sanding all edges and joins while still flat on the table.


















The frame was sanded and washed like the roof but for the vertical surface some double sided tape was added to each beam and then the adhesive / sealer applied alongside it. You can just see the red colour of the tape protective layer before it is peeled off. You can also see some supports under the bottom edge of the house frame which will help hold the panel in position while the adhesive sets. The double sided tape is quite interesting as it performs several functions. Unlike woodworking adhesives where for the good ones a very thin layer is required these adhesives require quite a reasonable thickness to remain, in the order of approx. 2mm thick. The double sided tape is about that thick - so it provides a gripping force to hold the sheet in place while he main adhesive sets and also provides a very even "packer" to prevent the adhesive being squeezed out.


















The sheet is then lifted into place and pressed firmly onto the adhesive tape.



































At this point a break was taken to make the last side panel as it had not been previously prepared.
Again it was interesting to see the technique.
The outside surface is a layer of fibreglass coated with a very smooth layer, called the "gel coat" which is imported from Europe in a large roll.
The required amount is rolled out face down and cut off.


















A layer of fibreglass resin and chopped glass strand is then sprayed onto the back surface


















and carefully rolled out to remove air bubbles


















Then thin sheets of ply are layed edge to edge along the wet fibreglass to end up being bonded to it.
Now the owner of the business tells me he has a complete vacuum bagging system but insists the following system gives at least as good a result!


















So while that sets in preparation for fitting tomorrow the first side is also prepared. Lots more of the sanding, washing, taping and gluing. The red protective covering of the tape is removed before fitting up.


















The side is then lifted into place and "pushed" firmly into contact with the tape.


















From the inside holes are carefully drilled through in all the corners of the areas to be cut out.


















and then the pieces carefully removed with a sabre saw.


















So tomorrow should see the remaining end and wall in place and the rest of the cutouts done.

Then begins the corners and edge finishing of all the cutouts.

I seem to get the feeling that the quick part may be over . . . but it's great progress so far!!

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