So, my brother gave me a viola. Not just any viola. The viola he used in middle and high school orchestra.
See, he discovered that he could get a viola that actually works for not much money on eBay. So he gave me the one that you can't tune. It's pretty normal, except it has pegs made by Roth Caspari which are somewhat abnormal. They're lockable. Basically, they've got a metal bushing and a clutch in them. Unfortunately, the hole they require in the scroll is very very large compared to normal pegs, and the one for the A string has in fact been reamed too large for even these. So A always slips.
So, the first thing I did was order some pegs that might fit in some way. In this case, Schaller adjustable ones that work just like the Roth Casparis. The Schallers claim to come with an extra wide bushing for large holes.
The extra-wide bushing is smaller than the Caspari bushing. Grrr.
To make a long story short, I eventually decided it was worthwhile just to glue the bushing into the scroll, and then assemble the peg around it. This worked out just fine, and the viola (which hasn't been tunable in 6-7 years) appears to tune just fine at the moment.
Oh, and it's very hard to find an A string for a Viola at 7:30 on a monday night in Raleigh. "Music and Arts" in Crossroads was the 4th store I tried, and they did have them. I did talk to a very nice girl who solicited me as a violin student at one of the other shops though...
In related news, the Stewart-MacDonald catalog is kindof neat. How many 100-page sales catalogs have 25Kohm pots, Pedestal Buffers, and more than a page devoted to fret tools?