Techno
08-12-2007, 02:25 PM
This shows the cad picture cheat I mentioned before. It isn't exact due to the large size of the part but its close enough for this purpose. Smaller items come out just about exact since the picture distance VS part size is better.
After the picture was imported into cad it was traced for the important items, the hatch. This then has the units size set- its put to scale. A horizontal section was chosen, measured and set. But the small bulge measures 13" high but doesn't in the picture, about 10.5" instead.
http://i9.tinypic.com/4ve4miw.jpg
Anyway you can see how a part can be traced and then used to make its exact duplicate or figure out a geometry, like this case. The hatch was copied and rotated along the assumed hinge location. A few trials showed the ram, which is 15" long and extends 1' needs to be one closed length away from the pivot. In other words about 15". Arcs were drawn to show closed, open and the attachement point on the hatch. This point was also rotated to find it but it also is the intersection of the arcs. One arc being the hatchs rotation point. I figured the location from trial and error but it became apparent in about 3 trials.
Now that I've drawn out the coarse idea I can mount it a bit short of actual and it should work fine. Where to mount and where to attach was the unknown. How far would the hatch open?
You could flip the real one several dozen times too but I find this method easier... since its hot out.:D And very cramped under the hatch. Duplicating parts... or more accurately making a part to fit another part exactly is great using this method.
I've also used the same technique for seeing where the engine will be with the stock cowl and the custom one with the engine set back 1,1/4" instead of the full jack plate. In this case only the Outboard and custom cowl was traced. It was rotated on the boat picture. Turns out both interfere with the hatch but also shows the GPS antennae can be mounted between hatch and engine on the hand hole cover. The new location reduces the trailer trim of course but is still considerable considering its 4" closer.
After the picture was imported into cad it was traced for the important items, the hatch. This then has the units size set- its put to scale. A horizontal section was chosen, measured and set. But the small bulge measures 13" high but doesn't in the picture, about 10.5" instead.
http://i9.tinypic.com/4ve4miw.jpg
Anyway you can see how a part can be traced and then used to make its exact duplicate or figure out a geometry, like this case. The hatch was copied and rotated along the assumed hinge location. A few trials showed the ram, which is 15" long and extends 1' needs to be one closed length away from the pivot. In other words about 15". Arcs were drawn to show closed, open and the attachement point on the hatch. This point was also rotated to find it but it also is the intersection of the arcs. One arc being the hatchs rotation point. I figured the location from trial and error but it became apparent in about 3 trials.
Now that I've drawn out the coarse idea I can mount it a bit short of actual and it should work fine. Where to mount and where to attach was the unknown. How far would the hatch open?
You could flip the real one several dozen times too but I find this method easier... since its hot out.:D And very cramped under the hatch. Duplicating parts... or more accurately making a part to fit another part exactly is great using this method.
I've also used the same technique for seeing where the engine will be with the stock cowl and the custom one with the engine set back 1,1/4" instead of the full jack plate. In this case only the Outboard and custom cowl was traced. It was rotated on the boat picture. Turns out both interfere with the hatch but also shows the GPS antennae can be mounted between hatch and engine on the hand hole cover. The new location reduces the trailer trim of course but is still considerable considering its 4" closer.