Printing envelopes for mailing with beamer presentation class

Question

I was able to print several U.S. #10 business letter envelopes 4⅛”×9½” (10.4cm×24.1cm) for mailing with more or less the code I have included below, but the beamer documentclass does not seem to respect the choice of papersize, and the geometry package appears incompatible with this documentclass and generates various "clash" warnings and error messages.

Envelopes of course are printed landscape mode, like the presentation slides, and at least on my printer, which I assume is not unusual, with the printable area vertically centered and right-justified, because the envelopes are loaded in with right edge leading.

I don't really think envelopes for mailing are that special of a case, either, for presentation slides. I basically just want to know the best way of specifying a custom papersize for presentation slides.

\documentclass[a5paper,12pt]{beamer}
\usepackage{minipage-marginpar}
\usetheme{default}
\beamertemplatenavigationsymbolsempty

\title{}
\author{}

\begin{document}
\begin{frame}[plain]
\hfill\begin{minipage}[t]{3in}~\\[1.25in]
Address 1\\
123 Main Street\\
City, State ZIP
\end{minipage}\linebreak
\end{frame}

\begin{frame}[plain]
\hfill\begin{minipage}[t]{3in}~\\[1.25in]
Address 2\\
Back Alley 2\,A\\
Postcode City, Country  
\end{minipage}\linebreak
\end{frame}

\end{document}

Answer 1

You should probably not use the beamer class since it is not made for typesetting envelopes. In section 8.3 of the beamer manual, apart from stating a row of possible frame size options (none of which fits a letter envelope format), it says:

Aside from using these options, you should refrain from changing the “paper size.”

However, you can essentially use any other basic document class and set the paper size and margins using the geometry package. For example like this:

\documentclass{article}
\usepackage{calc}
\usepackage[
    paperheight=4.125in, 
    paperwidth=9.5in,
    left=0.5in,
    right=0.5in,
    top=0.625in,
    bottom=0.625in
]{geometry}

\pagestyle{empty}

\begin{document}

\begin{minipage}[t][0.3\paperheight]{0.5\paperwidth}
\small
Return address \\
Some street \\
Some town, some ZIP code
\end{minipage}

\vspace*{.5in}
\hspace*{3in}
\begin{minipage}{3in}
\large
Delivery address \\
Some street \\
Some town, some ZIP code
\end{minipage}

\end{document}