Posts Made By: Jim Moscheck

Hello All and Happy New Year,

Last Spring when I heard that there could be problems with getting Pyrex I decided it was now or never so I ordered a premium primary mirror and a Pyrex secondary from Protostar for my first homebuilt truss dob. Well, the primary mirror is taking about 6 months longer than promised due to problems obtaining new blanks, but I've been told it has finally been started and I should receive it soon. Interestingly, I was on Protostars website today where is says that as of November they are discontinuing Pyrex diagonals and now only offering Quartz. My secondary was also received later than originally promised and I guess I got one from the last few batches.

http://www.fpi-protostar.com/pyrex.htm

Is Pyrex really dead and what will replace it for Newtonian telescopes?

Cheers,

I finally had a couple of hours this weekend to get back to work on my my telescope. I installed the Kydex in the UTA this afternoon and it when without a hitch. 8) My question is what is the best way to cut the hole for the focuser?

Since everyone's sending in cat pics here's one of Luna. She is very much like her namesake during the full phase, up all night and sleeps all day. Oh, and she LOVES the laser collimator.

Except for the telrad and finder scope bracket the UTA is finished!

Thanks Dave B. for suggesting the soldering iron for the focuser hole, it worked great.

My mirror cell should be done by next week and then it's on to the mirrorbox.

Emailed Ed Stevens and he said my mirror should be delivered within the month.

While on the subject of Pink Floyd, I purchased this a while back and just as Pulse is a good Dave Gilmour interpretation on Pink Floyd, the is just as good as it has a much different selection of songs which are obviously the ones that Roger sings. If I had to rate the two DVDs to say which one is better, I'd give the nod the this one. I still rate Dave Gilmour as one of my favorite musicians, but feel Roger just added so much to PF that couldn't and shouldn't be replaced. It's like if Paul McCartney and Ringo decided to record and tour as the Beatles. There, rant over.
Peace,

I can't believe it's been 40 years since the Apollo 1 fire that killed Gus Grissom, Roger Chaffee, and Ed White. It's also the 21st aniverary of Challenger today and this week is 4 years since Columbia. Brave men and women thet all were!

In 1967 I was a 10 year old space geek and watched every flight starting with Mercury with my Dad. My Uncle lived in nearby Melboure, and we went on a family vacation to Florida a month after it happened. I think my Dad was hoping to see the first test launch of Apollo, but instead I remember all the sadness that was everywhere, especially when we toured the Cape. We did get to see them launch a monkey which reached orbit , but was then lost.

Amazing that they reached the Moon just 2 and a 1/2 years later after a total redesign to the Apollo capsule.

Starting on the rocker and need to bond some plywood panels. The book says to jack your car up and place them under a tire. Well, that's not going to happen in February in Michigan. :S

Are there any alternatives anyone could suggest?

Oh happy day, oh happy day. 8)

I just had a visit by the UPS guy and he dropped off my brand new 14.5" f4.3 Ed Stevens primary mirror. Needless to say I'm totally geeked and now think I will be able to finish the scope before a planned star party down in Georgia after Easter. The numbers in the specs. book look fantastic, but I'll wait till I get it under some dark skies before I pass judgment. Here they are if anyone is interested. Ed told me a few weeks ago when he sent the mirror off to spectrum to get coated that I'd be real happy with it. Guess he wasn't kidding. 8)

RTA: 0.34
Strehl Ratio: 0.994
Peak to Valley Wave: <1/15th wave

Just last night I routed the ground board, finished drilling all the holes in the mirror box for the altitude bearings and the split blocks, and screwed and glued the rocker box together. Next step is to have "first light" on a distant radio tower to figure the exact distance between the UTA and the mirror box. Then tweak the balance ( hope my numbers are good) and finish with spar urethane on the exterior and flat black on the interior.

K&B says to use carriage bolts for the split blocks. I couldn't find stainless steel carriage bolts so I settled on hex head bolts. How do I keep the bolt from turning when I tighten the knob, or heaven forbid, if the knob works it's way off and the bolt then falls on my primary? Glue? Silicone caulk?

I'm also having problems locating a machine threaded eye hook for use with the wheel barrel handles. I can find partially threaded ones, but not fully threaded.

Thanks

I had a clear night to measure the distance between the UTA and the mirror box. I set the mirror box/rocker on the ground pointed at zenith. I made a couple of long "arms" from some scrap oak and screwed these to a ladder to suspend the UTA over the mirror box. Had to raise the arms a couple of times, but I finally saw some focused stars. I measured from the bottom of the split block holes to the bottom of the UTA and it was exactly what I figured from my scale drawing, 38 inches. I then cut the truss poles two inches longer and put the scope together for the first time. The finished eyepiece height will be about 5'3" which is perfect for me at 5'6". The last thing I have to do are the wheel barrel handles and their threaded inserts.
I can't believe I'm almost done.