I just came across your thread while looking for information on balsa double tops and came across your thread with pics of your melted vacuum cleaner vacuum pump. Find an old room air conditioner and take the compressor and use the input side of compressor as a vacuum pump. There should be enough oil left in the compressor for it to run for a few hours. It should produce a much higher vacuum than a vacuum cleaner can. You should be able to get 28 to 29 in Hg of vacuum.
How is your double top experiment coming along?
VuTran wrote: ↑
Tue Mar 29, 2016 1:54 pm
I think if the is the delaminations then it's because of the thin joints between the top and the Nomex. On this type of construction, the joints are 1.4mm and compared to some light bracings with 2.5mm wide. I don't think the delaminations will happen unless there is not enough glue on the skin. I added more glue than It need to be after weighting the Titebond when it dried.
My vacuum cleaner went to the heaven after two hours of hard working.
It's still working but It's better for my ears to let him go.