Crankset Conversions

David said:

I am mid-process [I have the triple cranks and triple front derailleurs
bought] in changing two mid-1980s roadbikes from road doubles to triples
to ease hill climbing, but recent posts here have me a little scared...

I knew I would need new bottom brackets or at least spindles, and
planned to let the LBS help in getting that right. Both bikes have
8-speed chains (one is a 6-speed and other is a 7-speed). Both have
(old) Shimano 600 rear derailleurs. Question #1: Will those rear
derailleurs likely work with the triple so long as I train the missus to
stay out of the small-small combos?

'
Yes...the issue will probably be bog-big combo tho...an artifically too
short chain to prevent pulley to biggest cog interference when in the
smallest ring-biggest cog combo.

Quoted message said:

She is more the slow-cadence grinder so the 52/42/30 will suit her. I
am a spinner and intended to go 45/39/30 or thereabouts. Question #2:
Will that present any added problems beyond putting the front derailleur
in the right place?

Nope-

Quoted message said:

Question #3: Would it be easier for me to dump the un-installed triple
equipment and go to compact cranks? Even getting down to a 34 would be
an improvement over the existing 42 small rings.

No compact is as low as the 30t smallest ring. All you have mentioned
will be fine with a short cage rear der. If extreme combos won't be
good for her, get a long cage rear der, like an inexpensive Deoe or LX
and that will work fine with all the rest of what you have-about
$35-$40 or so.

Quoted message said:

I understand that the chainring spacing on the triples is different than
on doubles. Question #4: Since our shifters are friction (I know, how
quaint) does that matter?

It's not-same spacing-no problem.

Quoted message said:

I wish we could afford two new bikes, but I just spent the equivalent on
textbooks for the kids in college, so the old bikes will need to get us
up the hills for 2-3 more years.

David

Don't expect a new bike to magically make you climb better. The
'bicycle' is a very small part of the cycling performance equation.