13-03-2013, 11:52 AM
Finishing off the wing core templates:
At this stage they have been cut and then filed as closely as possible to the printed profile, which is applied using double sided tape. the templates are made from some peices of 3mm alluminium sheet.
It's important to file it nice and smooth as any grooved or deep scratches will snag on the hot wire and impact on the quality of the finished core. Since these won't be sheeted in balsa I'm wanting the best surface I can get to Iron film on to.
After the templates are filed flat right to the line, I then darken the working edge with black artline pen. This makes the next step much easier
Then I champher the edges to leave about 1mm or a little less of the pen mark on the working edge.
The idea of this last step is to reduce the contact area so the wire doesn't cool down near the edges and also with a narrow contact area the wire will follow the shape much better. The very last step is to put a fine finish on the working edge with 600 grit emery followed by a quick polish with a scotch brite pad. and drill some mounting holes to fasten it onto the jig
Here is a pic of the jig that will hold the templates it will be reconfigured four different ways, to cut the profile of the left, right, top and bottom of the two cores that make up the wing.
On it you can see the lines I've drawn to align the peices of foam that the cores will be cut from. Both the left wing core and the right wing core are drawn on top of each other. Don't worry if it looks confusing All will become clear with the fullness of time and some more pics of the next steps
At this stage they have been cut and then filed as closely as possible to the printed profile, which is applied using double sided tape. the templates are made from some peices of 3mm alluminium sheet.
It's important to file it nice and smooth as any grooved or deep scratches will snag on the hot wire and impact on the quality of the finished core. Since these won't be sheeted in balsa I'm wanting the best surface I can get to Iron film on to.
After the templates are filed flat right to the line, I then darken the working edge with black artline pen. This makes the next step much easier
Then I champher the edges to leave about 1mm or a little less of the pen mark on the working edge.
The idea of this last step is to reduce the contact area so the wire doesn't cool down near the edges and also with a narrow contact area the wire will follow the shape much better. The very last step is to put a fine finish on the working edge with 600 grit emery followed by a quick polish with a scotch brite pad. and drill some mounting holes to fasten it onto the jig
Here is a pic of the jig that will hold the templates it will be reconfigured four different ways, to cut the profile of the left, right, top and bottom of the two cores that make up the wing.
On it you can see the lines I've drawn to align the peices of foam that the cores will be cut from. Both the left wing core and the right wing core are drawn on top of each other. Don't worry if it looks confusing All will become clear with the fullness of time and some more pics of the next steps
“The knack of flying is learning how to throw your machine at the ground and miss.”
"When once you have tasted flight, you will forever walk the earth with your thoughts turned skyward, for there you have been, and there you will always long to return." ~Leonardo Da Vinci