[5ash (Philip)]

I bought one of these for $50 in Aldi to look at the stars with the grand kids. Was not expecting great things but low power views of terrestrial objects look OK. However after looking at the collimation of the secondary with the focuser I think the views could be much better. When looking into the eyepiece the secondary appears to be about 1 cm too close to the top of the optical tube. I want to correct this by putting in longer adjustment and centre screw , does any one know what thread size these screws are? I'd imagine when I fix this I will have to look at the adjustment of the primary. I like challenges.
Hope someone can help regards philip