> Here is the design of part of my mount.
I have modified your design and wanted to send it back to you (and the list) to get your comments about it (I'm not suggesting that you change your design, I'm just curious). I have changed a couple of things:
1. Shortened the length of the shaft and moved the bearings closer together. No loss of rigidity should occur (may increase it, see #2), plus this makes the mount smaller and lighter.
2. Shortened the distance between the top bearing and the scope-plate. The longer this distance is, the more flex it will experience. You will be adding significant weight out on that lever.
3. Countersunk all your bolts/nuts and made your 1" steel shaft really 1", instead of 3/4" (purely ascii cosmetics :-).
I have a few questions about your design:
a. Why did you make the dec shaft so long and the bearings so far apart?
b. How do you intend to control the tension on the DEC shaft?
c. How will you allow manual or motorized adjustments of the DEC axis?
Print it out (12cpi), take a look, and tell me what I overlooked.
Andy Steere - dmislas@clark.umsystem.edu Central Missouri Astronomical Association
=============================BBBB=================================BBBB==========
==============================||===== Cradle for telescope tube ===||===========
==============================||===================================||===========
....||........+------------------+.......||....
1.0 Inch by 4 Inch ....||........| |.......||....
collar ------->....||........|<-- 1-5/8 Inch -->|.......||....
....||........| |.......||....
....||........| |.......||....
....||........| |.......||....
...NNNN.......| |......NNNN...
| |
||||+------+ | |
................|||||------|--------| |-----+
................|||||------|--------| |-----|
................|||||------|--------| |-----|
NN..............|||||------B--------| |-----|
NN=========================B--------| |-----| < Bearing
NN=========================B--------| |-----|
NN..............|||||------B--------| |-----|
................|||||------|--------| |-----|
................|||||------|--------| |-----|
................|||||------|--------| |-----+
====================||||+------+ | Shaft |
====================|||| | |
====================|||| | |
====================|||| | |
====================|||| | |
Polar Shaft=========|||| | |
====================|||| | |
====================|||| | |
====================|||| | |
====================|||| | |
====================||||+------+ | |
................|||||------|--------| |-----+
................|||||------|--------| |-----|
................|||||------|--------| |-----|
NN..............|||||-----BB--------| |-----|
NN========================BB--------| |-----|
NN========================BB--------| |-----| < Bearing
NN..............|||||-----BB--------| |-----|
................|||||------|--------| |-----|
................|||||------|--------| |-----|
................|||||------|--------| |-----+
||||+------+ | |
| +--------------+ |
| |+------------+| |
| || || |
BB|| ||NN
<- 1 Inch -> BB================NN
BB|| ||NN
^ ============ | || || |
| ============ +-+| |+-+
1 Inch | ============ | |
| ============ ---->| |<--- 1" Steel
| ============ | |
| ============ /\/\/\/\/\/\/\
V ============
\/\/\/\/\/\/\/
| |
| |
Counterweights go out here somewhere ----->| |
+------------+