Kapex extreme bevel?

[eightball]

I'm making some floating shelves that run floor to a sloped ceiling.

For two of the shelves I need to cut an extreme bevel to match the slope of the roof.  I need to cut a 69° bevel.

At first I was thinking of doing it with my TS55 using a jig like this:
German Track Jig

But when I dimensioned the cut it's going to be ~105mm so way too thick for my TS55.

So now I'm thinking Kapex.  Is there a similar jig I could use?

Two more challenges, one of the pieces is almost 10' long - not sure how I'm going to support that length at an angle.  Also, the shelves are 13" wide so that's a little beyond the Kapex capacity.

What's the genius solution that I'm forgetting?  How can I cut this bevel?

Thanks for any guidance or suggestions.

 

[morts10n]

My advice would be to stop the shelf an inch or 2 away from the sloped ceiling. Even if you could cut that extreme angle, it will likely not meet the slope tightly across the width. It will need to be scribed. It will look kind of goofy as well. Another option is to cut a channel in slope and slide the board into it. Patch afterward

 

[Crazyraceguy]

Seems like a job for a router fixture and a slab flattening bit.
That's how I would approach it anyway. The 10' board is definitely a limiting factor.

 

[tjbnwi]

[attachimg=1]

[attachimg=2]

[attachimg=3]

[attachimg=4]

 

[Crazyraceguy]

That works too ^^^ if you have a way to hold your stock in a vertical position and keep it straight.
Though I was assuming that this cut was across the end of a 10' board? (because of the Kapex reference)

 

[Willy Eckerslike]

What's the genius solution that I'm forgetting?

A handsaw.

 

[eightball]

Thanks all.  Yes it is along the end of the 10' board so unless I get really creative, I can't mount it vertically.

Unfortunately, I can't notch the sloped ceiling but I agree this is going to be tricky to match up.

RE: router fixture - can you elaborate on that? Conceptually I understand what you're saying but I can't picture the fixture.

Really appreciate the tips.

 

[Econoline]

This is a jig I use for extra-steep crosscuts. I guess you could make one for rips, but it would be kinda unwieldily.
tjbnwi has the solution for rips, clamp the material vertically.View attachment 1View attachment 2

E.

 

[Econoline]

Thanks all.  Yes it is along the end of the 10' board so unless I get really creative, I can't mount it vertically.

Unfortunately, I can't notch the sloped ceiling but I agree this is going to be tricky to match up.

RE: router fixture - can you elaborate on that? Conceptually I understand what you're saying but I can't picture the fixture.

Really appreciate the tips.

Set-up on a roof, let it run wild off the edge.
E.

 

[Crazyraceguy]

RE: router fixture - can you elaborate on that? Conceptually I understand what you're saying but I can't picture the fixture.

Really appreciate the tips.

The one I have is similar to the one Econoline showed, with the exception of turning the board over and cutting horizontally with a slab flattening bit.
The TS version cuts on the vertical plain, which causes problems with longer boards.
Mine is also angle adjustable. I'll post a pic when I can.

 

[ChuckM]

Make this simple jig (at the desired angle) for your saw:

Start from 6:30
=3yfAfmvQ21v5hS1B