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Hi Doug
Temperature shouldn't affect alignment too much on a small scope. The "getting worse" simply means it is getting bumped as you move it and it is getting further out of alignment. On my 12" I find collimation stays pretty well on through an observing session as long as I don't bump the tube and I regularly have temperature changes of 15-20deg over the course of a session. I know as I have a temp sensor attached to the scope.
You should be able to get it pretty well collimated without a laser. The first time I did it I just put my eye to the focuser tube and tried to line everyhing up so my pupil that I could see was in the centre.
First adjust the secondary mirror so you can see all 3 retaining clips on the primary and the image of the primary looks round. Then adjust the primary so your eye is in the middle. Thats all I did and for a small scope (8" or smaller) most people will be hard pressed to see the difference.
Just be carefull if using tools to adjust the secondary, have them tyed to a bit of string around your wrist, or have the tube pointing down so you don't drop anything on the primary.
Malcolm
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