Posts Made By: Bill Byrd

[COLOR="Lime"]This guy was hanging out in a leaf on the hibiscus out front tonight...waiting for dinner to arrive![/COLOR]
[COLOR="Purple"]Bill[/COLOR]

[COLOR="Purple"]Am I crazy to even try this?

Some background...I was shooting for a nice low profile mirror box. Unfortunately, the [SIZE="Large"]L O N G[/SIZE] truss poles necessitated by my semi-long focal length (f/5.22) mirror have thrown off my balance point by about 4 inches.

Soooo...I've extended the sides of the mirror box where the alt bearings will go by about 6 inches to bring the balance point into the center of the bearings. Now it's a split level mirror "box". I know I could make all of the side longer but that's just more weight. Ultimately I'll get the balance worked out and then trim away anything that I can do without. Should be interesting looking.

Is having different sized sides going to cause any issues? I can't think of any major problems. Maybe some flexure but I can address that with some cross pieces if necessary.

Oh well...at least it will be different from all of the usual scopes out there.
Bill[/COLOR]

[COLOR="Purple"]She's still waiting patiently for a meal to come close enough!
Bill[/COLOR]

[COLOR="Purple"]Still struggling with building this scope. :S The long focal length is making everything kinda difficult compared to past ATM projects. I'm tempted to bail out on this 18.75" f/5.22 celluler mirror and go to a traditional 18" f/4 mirror in 1.6" thickness. Mirror weight would be about the same and I'd take 26" off of the eyepiece height. Cool down would take longer but fans can help in that area.

Anyway, before I abandon this scope, I'll try to overcome the issues and see if maybe I'll grow to love it's quirks. 8O

Here's a pic of the extended mirror box sides. The truss attachments are still down low so any pole can go in any attachment point. The extended sides are only higher to allow the alt bearings to be higher so they are at the center of balance. In the pic you can see one lower side, one higher side, a truss attachment, poles, mirror face and alt bearing on the outside of the extended side.

The poles work fine with the two taller sides so that is not a problem.
Bill[/COLOR]

[COLOR="Purple"]How many of y'all (I'm a Texan ) have a trailer for transporting your astro gear to observing sites? My latest ATM project is probably going to push me to needing a trailer and I thought I'd see how many folks are using one. I'm thinking of getting a small 4X6 or 5X8 trailer that can be pulled by Scope Hauler, my PT cruiser.

For those with trailers, what have you found to be the pluses and minuses?
Thanks!
Bill[/COLOR]

[COLOR="Purple"]Remade the rocker sides today. Mounted the alt bearings (temporarily) today. Got to thinking about all of the tools I've accumulated over the years that I use to make telescopes.

Today I used:
Table saw
Jig saw
Band saw
Oscillating belt/spindle sander
Many clamps
Hand held belt sander
Cordless drill
Hand held block plane
Hand held sanding block
Several tape measures
Squares
Knife

Didn't use the router today but it gets a fair amount of use depending on the project du jour. Didn't use the drill press today either. The pieces of wood I was working with today are kinda large to be drilling with a drill press.

No real point to this post except that having these tools makes it a lot easier to make things like telescopes fairly accurately.
Bill[/COLOR]

[COLOR="Purple"]I get cold. I don't enjoy being cold.

Don't have heated socks yet but this winter I might get some.

I also might try one of the new heated vests that are available from another nameless retailer. Kinda costly at $150.00 USD but might be worth the price if it would keep me more comfortable in the cold. Hmmm...Christmas gift, perhaps??
Bill[/COLOR]

[COLOR="Purple"]...To quote Gene Wilder in "Young Frankenstein".

"It" being the 18.75" scope I've been wrestling with for the last few years.

Over the weekend I made the rocker sides...for the second time. I also made the rocker bottom...again. I cut the truss poles...for the 6th or 7th time. Do you see a pattern emerging?

After assembling the rocker for the second time, and cutting the truss poles another 1/2", I set the rocker outside on a piece of glassboard and set the OTA into the rocker. I did a rough collimation and popped in the 26mm EP to see if I had cut enough off of the truss poles. With lots of extraneous light flooding the FOV, I twisted the Kineoptics focuser and was rewarded with actual focused star images! So far so good. I may take another 1/4" off of the poles to fine tune them but for now they are okay.

I then spent some "quality" time checking sag and collimation change as I yanked the scope around. surprisingly, for such long poles that are in two pieces that screw together, there was not that much change. I found one spider attachment that was slightly loose, allowing some shift. Tightened that up. I think there is some movement in the secondary too but I need to look at that more carefully this weekend. The focuser board is also a little on the thin side and is sagging some. On the whole, I was surprised that there wasn't more shift. I'm happy!

After making two sides of the mirror box taller to move the alt bearings higher to get into balance, I'm now slightly back heavy. I'll move the alt bearings down slightly or leave everything as is and add an optical finder on the truss poles ala Kurt Mauer.

Having been up and down the ladder a fair amount in the last week, I can tell that a specialized ladder is next on the list. Wider and closer together steps are really needed to make standing more comfortable.

The pic is not from last night but it shows pretty much what the scope looks like at this point.

Still lots to do to have this monster really ready for use but it's creeping closer to being done. 8)
Bill[/COLOR]

[COLOR="Purple"]No, it's not a "male enhancement" question posted in the wrong Forum.

The minimalist design of my single upper ring has resulted in some flex when I hang a heavy EP in the focuser. Sooo...some beefing up is probably needed. The ring is 3/4" thick plywood and it's 1.13" wide.

My question to this august group is: Do I increase stiffness most by making the ring thicker or wider? I can see both ways working but I have no idea which is the best way to go.

What say ye?
Thanks!
Bill[/COLOR]

[COLOR="Purple"]To try and stiffen my single upper ring, I'm adding a second ring. The dowels are inserted into holes in each ring about 1/4" deep. This seems to make for a very stiff structure, even before the dowels are glued. Original ring (bottom) is 3/4" plywood. New ring (top) is 3/8" plywood.

The price to pay is an added pound of weight hanging way out on the truss poles. That may be okay as I'm a little back heavy right now. Once this is all done, I'll adjust the alt bearings placement for best balance.

I'll post another pic once I glue it up and reinstall the spider and focuser.
Bill[/COLOR]