How do you retopo hard surface models? (like this one)

Like this sword:


(it’s not the highest subdiv, but blender has problems with high polygon count).

So how would I retopo this in blender? Ok normally I would model the low poly first and make the high poly from there, but let’s assume I did the high poly first.
I know there is an optimization technic in 3ds max, I don’t know if it works well in blender.
Decimation gives bad topology and shading issues. (also I want to be slective what detail to keep on low poly)
So I need the siulette, but I don’t think the snap tools are good for this. (snapping vertices exactly on the edges seems to be hard)
What are my options? (in Blender or does other program do it better?)

**I hope attachment is fixed now.

Your attachment doesn’t work.

Those videos are not really helpful. Most of those tuts about organic models, nothing about how would you capture a siulette on a sharp edge like on the sword’s blade. Snapping to face is not reliable there.

If you just want a silhouette, simply place the sword in orthographic view and trace it with vertex and edges.

If that’s too much work, you can make a orthographic image file and trace it automatically in Inkscape. Bring the vector drawing in to blender as a curve.

Yes this is a quite simple model, but if this was the iron throne, or some really complicated hard surface model with many sharp edges it could be impossible to trace it.

Would be cool if there was an option in Blender to mark edges on the high poly model (manually and/or by angle) and then there would be an option in the snapping menu to snap to other object’s marked edges. Would be very easy to retrace the model in 3d. (edge snapping doesn’t work in blender and without marking which edge to snap to wouldn’t be good anyway)

But i was just asking to see whether anyone has a good method for hard surface retopo with many sharp edges.

You can use the new Contour Retopology tool with a setting of three vertices for the blade. It should work well and should be a breeze to do.

Edit:
Although II’m not sure why isn’t edge snapping working for you, last time I checked it worked perfectly.