3D Models Of Hooks

[Vodkaman]

Wise words, Slowfish and Bob.

 

Dave

[SCAngler]

One solution for generating the complex curves on hooks without true arcs, is to take an image of the hook, insert the image in a sketch in your CAD program, and sketch over the image. When your finished scale the sketch to the correct height(or scale the image first, this has been difficult for me in the past). Measure the Top of the hook to the tangency of the bend. This has worked great for me, and as Bob has mentioned, these hooks have a wide tolerance so you'll need to keep ~0.005" clearance in CAD depending on how your fabricating the mold. The key is to use splines, and only use two or three control points. This will allow for better control over the complex curve without inducing inflection points.

Or, import the image into the free program Inkscape and use it to covert the image into a vectorized file. This will import into your CAD program as a DXF or DWG. Then you can use these lines to generate the appropriate arcs.

Both methods work, but I like the parametric value of properly dimensioned splines, so I use that.

Off topic: It's hard to believe, but I have been very successful in molding shakey heads using Ren shape board. It's a type of polyurethane board which does not have a melting point that can withstand the temperature of melted lead, BUT the heat transfer between the lead and Ren shape doesn't ocurr fast enough to scorch the urethane. One note, I use this material for making less than 500 jig heads. Over 500, buy aluminum. Ren shape just allows me to quickly machine the mold and prototype a pot load of jig heads before I go down the aluminum road.

Sorry for diverging there, just thought it might spur some thought.

[mark poulson]

One solution for generating the complex curves on hooks without true arcs, is to take an image of the hook, insert the image in a sketch in your CAD program, and sketch over the image. When your finished scale the sketch to the correct height(or scale the image first, this has been difficult for me in the past). Measure the Top of the hook to the tangency of the bend. This has worked great for me, and as Bob has mentioned, these hooks have a wide tolerance so you'll need to keep ~0.005" clearance in CAD depending on how your fabricating the mold. The key is to use splines, and only use two or three control points. This will allow for better control over the complex curve without inducing inflection points.

Or, import the image into the free program Inkscape and use it to covert the image into a vectorized file. This will import into your CAD program as a DXF or DWG. Then you can use these lines to generate the appropriate arcs.

Both methods work, but I like the parametric value of properly dimensioned splines, so I use that.

Off topic: It's hard to believe, but I have been very successful in molding shakey heads using Ren shape board. It's a type of polyurethane board which does not have a melting point that can withstand the temperature of melted lead, BUT the heat transfer between the lead and Ren shape doesn't ocurr fast enough to scorch the urethane. One note, I use this material for making less than 500 jig heads. Over 500, buy aluminum. Ren shape just allows me to quickly machine the mold and prototype a pot load of jig heads before I go down the aluminum road.

Sorry for diverging there, just thought it might spur some thought.

 

Man, I love it when you talk dirty!  Hahaha

I'm so lost when it comes to all things CAD, this is like reading a foreign language to me, but it's fun, anyway!