In a message dated 98-10-21 23:48:31 EDT, you write:

<< Two questions:

 1. I was told that Dap 33 was designed for metal and synthetic window
 sash and that linseed putty was best for wood sash.  Peter's message
 implies there is something wrong with linseed putty.  If so, what
 is(are) the problem(s)?

 2. I would like to know more about Sonneborn NP1 urethane sealant.  How
 is it packaged and how is it applied?  Is it hard to handle (quick
 drying, hard to cleanup, etc.)  Where can I find it?  Can I assume it
 can be painted?  If so, how soon after application? >>

Thomas,

The problems I have with Dap 33 and oil based putties/glazing compounds, which
I have been using for decades, is primarily with wood sash manufacturing. Dap
makes another product for metal sash, although I can't recall the name at the
moment.
1. The inconsistency in materials which results in occasionally wide
variations in consistency, drying times, and poor performance.
2. The long drying time for both Dap and linseed oil based compounds. Although
Dap reps will tell you it can be painted as soon as it "skins over", it is
best to wait at least a month before attempting to paint with a brush. If
painted too soon, the glazing compound will tend to dissolve slightly and make
an awful mess. Long drying times of 1-2 months put projects in limbo (former
Roman Catholic guilt still makes me worried about the afterlife), and clog
work flow and can test customers' patience.

On ][<en's suggestion, I am testing NP-1 and will let you know what I think.
It is caulking-cartridge packaged, gunnable, toolable, and flexible. Like Sika
1-A, it probably with stick to air, hopefully for a long time

A good industrial/commercial building supply distributor should stock a supply
or you can find info about Sonneborn at http://www.chemrex.com/index.html