Posts Made By: Mike Pupeza

What is the 'best' way to make the focuser hole in a 12" dia. .094 Hastings Aluminum tube?
My last attempt, in a 6" dia. .094, used a round metal hole saw and was messy and needed a lot of filing and cleanup. The center bit drill chewed a bigger hole in the aluminum and the hole saw chattered around a bit. Fortunately, I used one that was smaller than needed so filing cleanup took away most of the damage!
I expect that a 'Greenlee' style threaded hole punch would distort the tube.
I'm putting in a 2" DAR dual Helical Focuser, so the hole will probably need to be over 2 1/2" (I'll get an exact measurement when I take it off the old tube!).
I suspect that there's no easy way, but any helpful hints would be appreciated.
Thanks.
Mike
6" f6 homemade on old Meade GEM
10" f4.5 homemade on old Meade GEM (WSP2008 Version!)

I have a 10" f4.5 Newt on a GEM, where the eyepiece, if set up on top of the tube when polar aligning, requires me to stand on a stool to see through the eyepiece.
Is there an optimum location, scientifically, where I could rotate the tube and eyepiece and see through properly for 'most' of the observable sky?
I am at 45N. My horizon is usually mushy so I don't observe very close to it, and there's really not much around Polaris that I usually observe.
I realize that I can try several locations, but thought there may be some good advice here. My tube doesn't easily rotate, but can be turned, screwing up my DSC settings till I re-align.
Any thoughts?
Mike
10" f4.5 Newt (Homemade)on old Meade Starfinder GEM
6" f6 Newt (Homemade) on old Meade Starfinder GEM

The recent discussion on Powder Coating reminded me of a few suggestions for ATMs changing out, or making new scope tubes.
I changed out my old 12" hybrid cardboard, fiberglass, aluminum sheet 48" long scope tube, which had many extra holes, bangs, chips, scrapes, etc., for an aluminum tube ordered from Hastings Pipe Company.
I ordered the .094' thickness, but should have ordered the .064" thickness. .094" is too heavy for my 12" dia. X 48" length. On my old Meade Starfinder GEM, even sliding the 25# weight to the end of the shaft wasn't enough, so I found an additional 8# weight and then balanced it out.
Using the .064" would have saved about 7# and the added weight wouldn't have been needed.
My consolation is that my scope is as sturdy as a tank!
Oh yes, I had the tube powder coated in Melbourne FL for about $80 - so the tube plus coating came to about $200. Again, cost saving for the thinner tube would have been about $25.
The powder coating is an excellent way of going. It's about the same price that I was quoted from an Auto Body Shop for painting and I've been pleased.
Black auto body lip edging trims out the ends and makes it look pretty good!
At the Winter Star Party, I got some pretty good viewing in, especially after I installed the extra counterweight!
Mike
6" f6 homemade NEWT on old Meade GEM
10" f4.5 homemade NEWT on old Meade Mount

I have 2 DAR Double Helical 2" Focusers, which I like very well.
What is the best way to clean and lubricate them?
They are getting stiffer to rotate, especially when further into the barrel.
I enjoy these 'built like a battleship' focusers as they don't care how heavy
the eyepiece or camera is.
I am not getting any answer back from Joe O'Neil who sells them, nor Dave Rubenhagen who makes them.
FYI, they are made of aluminum running on phosphor bronze on aluminum which tend to self lubricate but need cleaning. WD40 is used as a cutting oil to lap these together so is not suitable as a cleaner/lubricant.
Thanks
Mike 10" f4.5 home made Dob

At the recent Winter Star Party in the Keys in Florida, I had several occasions to have to use a white light to find things in my storage boxes at night. I was surprised to find that my Night Vision had NOT diminished as much as I expected, if at all. My 220LUX 1 W Cree HWA WYS UniqueFire S10 Tactical Flash-light was the one I used.
Has anyone done any studies on the spectrums of these types of light as to their Night Vision diminishing qualities?I suspect that their limited spectrum and lower overall power may work as well as dim red filtered incandescent flash-lights, and give better visibility. I do know that several of my Solar Calculators do not work with this flash-light. Of course, if you look into the lens, you will be temporarily blinded.
Interesting if anyone will do some studies.
Mike .....>

Title pretty well says it. It tells me "These credentials do not match our records."
Same creds as regular Astromart!
Mike .....>

I had a suggestion to use nichrome wire instead of resistors on the primary mirror. I did a test wind of some #24 wire on my old polishing tool, and by using a folded wire spiralling outward from the center, found that I can get about 10' of wire to fit nicely spaced. I found a supplier, on that auction site that shall not be named, that had 40' of suitable stuff that came to about $12 with shipping. It's a bit over 1 Ohm per foot, so it should work fine.
I do have to wind carefully to leave a space for the mirror mount supports!
I probably will use the 330 Ohm resistors for the secondary mirror, as per another suggestion!
Any other ideas?
You're doing great for me so far!
Mike.....>

Boy!
Did I ever ask a stupid question!
I 'really' did think there was an answer!
Mike......>

I've ordered and been happy with my 12" OD X 48"L aluminum tube from Hastings Irrigation for my 10"f4.5 Newt.

They cater to ATMs for those sizes shown and ship UPS in sturdy cardboard boxes with square cut plywood end supports.
I was able to get the tube powder coated from a shop in Melbourne, FL for around $100. VERY nice job and far better than trying to paint it.
Good luck.
Mike .....>