CNC Depron machining + film

[Rod AshtonParticipant @rodashton53132]

Anyone CNC machined 6mm Depron pre-covered in coloured film?

Object is to build aircraft from "Flight Test" plans. https://www.flitetest.com/articles?grid=true#/textSearch=FTScratchBuild,

This normally requires 4mm double paper covered foam board, apparently unavailable in the UK. This can then be spray painted (or pattern over skinned) as desired.

I have scratch built a couple but consider it would be an interesting exercise to "Anglicise" the plans and CNC the profiles. Possibly part cut the all important fold rebates. The CAD can be modified to adjust fit and form for "our" 6mm Depron. e.g, to suitably modify the wing profile cutout in the fuselage. – If the foam can be pre-covered and machined the the Flight Test plans and build principles can be maintained, Plus the outer surfaces would be colour skinned requiring minimal finishing..

If you have been there and/or could advise please be kind enough to make contact.

[Rod AshtonParticipant @rodashton53132]

[Gordon TarlingParticipant @gordontarling37126]

A fellow club member builds the Flite Test models from the paper covered foam, but he cuts it all with his laser cutter – they do build and fly well. The only slight problem with using the laser cutter is that the core foam melts back from the edge slightly, though usually not enough to be a problem. Not sure where he buys the foam board and I can ask him when I next see him, but have you tried artist's and framing suppliers? I was buying thicker black board for mounting photos from Lion.

[Rod AshtonParticipant @rodashton53132]

Gordon – Many thanks for your help. I looked into laser cutting as an add-on to my router. But could not happily gather all the info I required to fit it up.

I would be especially pleased to know if there is a source of 4mm paper backed board. It would save a huge amount of re-draughting.

I visited the Lion site but could not find 4mm board. Will give them a call on Monday.

Regards

Rod

[Gordon TarlingParticipant @gordontarling37126]

Rod – Took a look myself and it seems that 4mm board is hard to come by. I'll email my clubmate to ascertain what thickness he uses and where he gets it from.

Gordon

[Rod AshtonParticipant @rodashton53132]

Gordon – Thanks. I would be grateful to know what laser setup he uses, if you would be kind enough to ask.

Rod

[richardandtracyParticipant @richardandtracy]

Kapa Board is available in the UK. Not in 4mm, but 3 & 5mm, both of which are closer to 4 than 6mm. May help a little.

Regards,

Richard.

[Rod AshtonParticipant @rodashton53132]

I have been advised that the solution to the board thickness is easily overcome by simply scaling the whole plan up, in the case of 6mm Depron (x140%) or proportionally for 5mm foam board available here in the UK. It is not a simple 4mm to 5 mm @ 125%. The proportion should be made using the relative actual board thickness.

By converting to .dxf in Inkscape both my cnc router and plotter/cutter can read and cut the files.

richardandtracy – would you have any 5mm Kapa board that you could gently measure for me please?

[Rod AshtonParticipant @rodashton53132]

Just had the opportunity to measure an FT kit and surprisingly their board measures 5.2 to 5.3mm. With their folding grooves cutout at 4.2 mm. My paperless 6mm Depron measures 6.0 to 6.2 mm. Anyone have a thickness dimensions for UK purchased papered foam board for comparison please.

[Gordon TarlingParticipant @gordontarling37126]

Rod – I just sent you a PM.

Gordon

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