I am new to knife forging and would love to get into Japanese blades. I have a couple questions and would appreciate any feedback in hopes of saving myself some trial/ error.
 I have watched hours of videos but unfortunately most will tell you what they are doing instead of why.

1.) Does only the Habaki touch the scabbard? I understand the blade and tip do not touch, does any of the spine touch?

2.) Can i leave a ricaso on the blade to act as a Habaki? If so, do i need to taper it down like a habaki or can i leave it with 90degree edges on the spine side?

Basically trying to avoid the more complicated parts like the Habaki and seppas for now while i dip my toe in the water.

-Thanks, Derek

I ummmm never mind, Just do it and have fun

5 hours ago, Steve Sells said:

I ummmm never mind

In the “fools rush in” department, I’m going to suggest that if you’re new to knife forging, you should (a) steer clear of something as sophisticated and precise as a Japanese-style blade and its furniture and (b) not think about messing with proven designs until you’ve got the chops to carry it off. 

I’m pretty new to bladesmithing myself, and the one thing I’ve learned so far is that I need to stick with basic stuff for the foreseeable future. 

"I really want to do "this"; so can I do something totally different instead?"  Is how I read your post and it leaves me scratching my head too.  Are you suggesting making an integral bolster to serve as a method of positioning a blade in a scabbard?  And have you studied how a katana is sheathed?  There is several feet of steel sheathed BEFORE the habaki engages in the throat of the scabbard.  Now if you are interested you might look at some of the pictures of Tom Maringer's blades where he uses aspects of Japanese hilting on western style blades.  There are a couple of breakdown shots out there as I recall.

You're a little off on your understanding of the katana basics, research that more before you get started but dont avoid fixture making. jump right in. making habaki for the first time was a great experience for me. i completely vaporized the first two i tried to make (dont even try to heat copper with coal). just get some copper, silver solder and solder flux and some flat bar stock and try it a few times.

here is one of mine

 

These guys are doing it right - I do not even try. I take measurements, plug it into Rhino, and 3D print then cast those xxxxxxxxx.

Hopefully you get the idea that this is a particularly hard step in a already difficult process

 

If this is your first knife I recommend good ol' K.I.S.S.