With respect, that seems improbable.  The web site for Ohaus (the only
"brand name" beam balance manufacturer I have found) does not mention
such instruments.  None are listed on eBay. Nor did I find one on any
of several laboratory supply web sites I checked.

I responded to the previous post from the assumption that the poster
knows about something rather exotic and difficult to find.  Another
possibility is that no such thing exists.

My email address is LLM041103 at earthlink dot net.

I appreciate the professional experience you can bring to this topic,
but it still appears to me that the scale is a better approach (for
me).

Some drugs have a limited useful life when dissolved, so that I might
have to throw away most of each batch I mix up. I could avoid that by
mixing smaller batches, but that would greatly increase the amount of
work required. (Information on suspension life seems to be hard to
find.  I did not see any in the drug information pages I found on the
Web.)

And of course I can't predict the suspension life of other drugs I may
have to give in the future.

Nor can I assume that those other drugs will either be very safe, like
Tylan, or come in tablet form and have an acceptable flavor when
prepared as a suspension. And I would always wonder whether any given
drug that is "very safe" is actually safe for my cats, who both have
impaired renal function, and can be expected to develop more problems
over time.

I'm comfortable with paying $250 or so for a laboratory scale.  In the
short run, I can recoup the cost through what I will save in two or
three months of use.  In the long run, I can recover much of it by
reselling the scale, or I can use the scale for other purposes.  I
used to make wine, and would like to do so again; a precision scale
would be nice to have if I do.

Regarding complexity, I don't see the problem.  Perhaps, from
experience, you can make this clearer. On one hand, I can prepare a
liquid suspension by powdering some tablets and performing a serial
dilution, then administer it by drawing a measured volume into a
syringe, putting it in the cat's mouth and hoping it all stays in, and
cleaning the syringe. On the other hand, I can powder some tablets and
put a measured amount of powder in each capsule, then administer it by
popping a capsule into the cat's mouth, followed by some water.

The capsule approach seems no more complex than the suspension
approach, and perhaps a little less so, but the labor is weighted more
toward the preparation end of things, and less toward administration.
When I have to administer four different drugs on a weekday morning,
I'll appreciate that.

Space permitting, I can combine drugs that are to be given at the same
time in a single capsule, simplifying the process further for both me
and the cats. On weekday mornings I'll appreciate that, too.

The one difficulty I foresee with capsule preparation is how to get
tiny amounts of powder into tiny capsules efficiently and reliably.  I
have never seen a funnel small enough to fit into a #3 capsule, and if
I had one, I would expect the powder to cling to the walls or plug up
the neck.

My email address is LLM041103 at earthlink dot net.