I spent some time experimenting with cutting holes in the middle of the foam to be able to cut out the lift fan.
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| Initial scaled hole required for the lift fan |
Once I had the initial lift fan hole, I then created a set of overlapping squares to make cutting with a straight knife easier.
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| Internal polygons to cut with the straight knife |
I've been avoiding using the jigsaw to avoid lots of foam sawdust. However to get started I used a spad drill bit to make an easy way to start the cutting. But that created a bunch of foam dust anyway.
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| 1" drill bit |
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| Drilling through the foam is quick work. |
Using the 4 drilled corners made cutting straight forward.
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| The resultant holes |
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| Cutting between the holes |
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| One square cut out. |
After cutting out one square, I could relatively easily cut away the small corners of the offset square.
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| Cutting out the extra corners |
The net result was most of the area filled out.
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| The final resultant hole |
I specifically kept the slight interior flanges so that the cowling can have something to rest on when it is installed above. There will be some experimentation later I'm sure about how to secure and seal the cowling to the body.
