Join wedge with single bond in chemfig

I am not really an expert on pgf and tikz but I find a (partial) solution. Modifying the chemfig default values with setchemfig produces:

\documentclass{article}
\usepackage{chemfig}
\begin{document}
    \setchemfig{
         atom sep=15pt,
         cram width=3.0pt,
         cram dash width=0.75pt,
         cram dash sep=2.0pt
         bond offset=0.75pt
         bond style={line width=0.75pt}
    }
    \chemfig{-[::-30](-[::60])<[::-60]-[::60]}
\end{document}

I use usetikzlibrary{decorations} to create a custom Cram bond, based on @pisoir answer in How to make only one part of double bond bold with chemfig?.

\documentclass{article}
\usepackage{chemfig}
\usetikzlibrary{decorations}

\pgfdeclaredecoration{crambond1side}{initial}{%
    \state{initial}[width=\pgfdecoratedpathlength]{%
        \pgfsetfillcolor{black}
        \pgfpathlineto{\pgfpoint{0pt}{0.3pt}}
        \pgfpathlineto{\pgfpoint{1.10*\pgfdecoratedpathlength}{2pt}}
        \pgfpathlineto{\pgfpoint{0.96*\pgfdecoratedpathlength}{-2pt}}
        \pgfpathlineto{\pgfpoint{0pt}{-0.3pt}}
        \pgfusepath{fill}
    }
}
\tikzset{CramRight/.style={decorate, decoration=crambond1side}}
\tikzset{CramLeft/.style={decorate, decoration={crambond1side, mirror}}}

\pgfdeclaredecoration{crambond2sides}{initial}{%
    \state{initial}[width=\pgfdecoratedpathlength]{%
        \pgfsetfillcolor{black}
        \pgfpathlineto{\pgfpoint{0pt}{0.3pt}}
        \pgfpathlineto{\pgfpoint{1.10*\pgfdecoratedpathlength}{2pt}}
        \pgfpathlineto{\pgfpoint{\pgfdecoratedpathlength}{0pt}}
        \pgfpathlineto{\pgfpoint{1.10*\pgfdecoratedpathlength}{-2pt}}
        \pgfpathlineto{\pgfpoint{0pt}{-0.3pt}}
        \pgfusepath{fill}
    }
}
\tikzset{Cram2Sides/.style={decorate, decoration=crambond2sides}}

\begin{document}
    \setchemfig{
        atom sep=15pt,
        cram width=3.0pt, cram dash width=0.75pt, cram dash sep=2.0pt,
        bond offset=0.75pt,
        bond style={line width=0.75pt}
    }
    \chemfig{-[::-30](-[::+60])-[::-60,,,,CramLeft]-[::-60]}\quad
    \chemfig{-[::-30](-[::+60])-[::-60,,,,CramRight]-[::+60]}\quad
    \chemfig{-[::-30](-[::+60])-[::-60,,,,Cram2Sides](-[::-60])-[::60]}\quad
\end{document}

The final result