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View Full Version : NEW MEMBER: hello from northern Ireland.



owen3371
11-09-2014, 12:22 AM
Hi all and I've stumbled upon this forum a month ago while I was looking at the possibility of purchasing a cnc machine,I eventually did and bought a cnc 3040t which a lot of forum members have done,im mainly interested in milling wood as I would occasionally get a commission to build a wooden static model aircraft which used to take 3 weeks by hand! But mainly I want to learn a new skill over the winter and broaden my hobby engineering skills.
Owen.

EddyCurrent
11-09-2014, 10:46 AM
Welcome Owen, with regard to these models, obviously balsa wood is the stuff for flying models but what kind of wood do you use for the static models ? and what thickness ?
Also does your machine do the job adequately ?

owen3371
11-09-2014, 01:42 PM
Hi eddycurrent
I usually make my models with whitewood pretty cheap wood you can find anywhere,I want to make more intricate stuff with more detail,also I want to learn a new skill this winter so im excited about getting the machine13364it Will be a learning experience !here's a Pitts special I hand built for my son Darragh last Christmas:-)

EddyCurrent
11-09-2014, 05:12 PM
Nice little plane, have you thought about you are going to cut the parts on cnc ?

owen3371
11-09-2014, 07:38 PM
Dunno,I obviously need to do symmetrical wing sections and elliptical fuselage etc,so thats where you guys come in,is it possible on a cnc machine?

EddyCurrent
11-09-2014, 08:38 PM
Dunno,I obviously need to do symmetrical wing sections and elliptical fuselage etc,so thats where you guys come in,is it possible on a cnc machine?

Well your machine will likely have X,Y,Z axes, so it's a 2D and 2.5D machine. 2D can be thought of as cutting shapes out a sheet of material, specifically the outlines in the X,Y axes.
2.5D is using the Z to cut curves, pockets, etc. it's not true 3D becasue it can't undercut. To make a statue for example with undercuts you would need a 4th axis that rotates the work, having said that, it is possible to rotate the work by hand provided you have used a 3D model in your CAD software and calculated each toolpath in your CAM software as the model has been rotated.
So taking your fuselage, you would lay it on it's side and do 2.5D cutting up to the halfway point, then turn it over and cut the other side, basically like joining two halves of an Airfix fuselage.
So yes it's possible to make the plane with your machine if you think creatively about how to position the stock and how you calculate toolpaths in your CAM software.

owen3371
11-09-2014, 08:56 PM
Nice one,thats what I want to hear,I reckoned that was the way to go about it and calculate the flange to be left then simply sand off the flange,im intending to make moulds for desktop scale GRP models(I fly full size airplanes) so there is a demand from pilots for the models it would make a production line possible :-)

Fivetide
15-09-2014, 12:37 AM
Hello I've been away for a while so catching up myself.. enjoy our stay I no have :)