Mine is very similar to Toms. I got a 1.25" aluminum tube from Home Depot that is actually exactly 1.25" O.D. and I found that the lid for a can of spraypaint pressed on the end nicely (you know the inner tube part that's on most spraypaint can lids). Then I just trimmed off the excess and made a hole in the center. Works perfectly! You can drill some small holes and epoxy in some small wire cross hairs near the end if you want to but for aligning the mirrors I made a laser out of the same tube and a laser pointer. Not nearly as fancy as some out there but it's all in the collimation for how good any laser tool is. I use that align the secondary then put that tool in an old barlow to align the primary. It goes pretty quick and is surprisingly accurate.

I use those two tools plus the barlow 99% of the time despite having a full compliment of Catseye tools... let the flaming begin LOL.

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I just wanted to add that using the two homemade tools gets me pretty darn close as confirmed by my autocollimator, certainly close enough for my f/6.
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