making a usuable 4T, I need help!please

[Peter Laidler]

I say, when making a replica, do NOT go by the drawings. They are an ideal, the perfect theory and not 'done-it' practice. 1st and MOST important, collimate the telescope optical and mechanical axis. Mount the front pad and sweat it on. Then adjust the rear of this pad to swing the graticle to centre on the azimuth of the bore against the DAP. Lift or lower the rear pad* to suit suit what you have achieved so far. Point of grat SET TO 100 and tip on the DAP. When it's EXACT, sweat everything on using clamps. Test again. When it is perfect only THEN start drilling of doing anything that will take what you're doing past the point of no return.

That's it said very simply. There is a half decent amateur attempt by me at putting this into a readable semi technical thread somewhere too that one or two have followed simply enough. There are also true experts out there who's understanding of the optics, mechanics and optical/mechanical collimation is greater than mine. BUT whatever you (or anyone else attempting this) stick to one tried and tested idea

* If you have to make a rear pad to suit, it is quite a simple matter but Fulton make pads that are a good fit with some simple hand fitting