monoxide
11-02-2007, 08:08 PM
after looking around there are a *lot* of ways that people have for really making that azimuth motion on a dob base smoother so i thought id share how i got mine nice and smooth regardless of the temperature.
Azimuth motion fix.
-----------------
what you need.
1) a few milk bottle washers
2) a tin of 'Gilly Stephenson's Carnauba Polish' (from mitre10)
3) all the neccessary tools to pull your base assembly apart.
4) clean rags/polishing pad/buffer etc...
it doesnt take a lot to work out what your going to be doing from here but ill go through it anyway :)
if you dont know what milk bottle washers are or what to do with them, there is a guide in the 'Projects & Articles' section that you need to check out
anyway you will need to pull the base apart so you can polish the top section where the pads slide, i pulled my base completely apart to make it easier to manage.
once your all set, get into the polishing.. this stuff is absolutely magic, and the finish you get is a HARD coating so it is not acting as a lubricant and wont scratch off easily, it is just filling in all of the rough parts in the laminate, making it silky smooth for the teflon pads to slide on.
be fussy when your doing it, the more time spent polishing the more adjustment you will have later via how tight you do the bolt up.
once youve polished the base up (this part is probably optional) you can add a bevel to the edges of the teflon pads so they glide over rather than grab and scratch into your new waxed surface. (i used a razor blade)
once you put it all back together prepare to be amazed at how smooth it glides, i remember before doing this i could turn the bolt holding the base together, now its tight enough that you cant turn it by hand, holding everything very securely while still allowing silky smooth motion.
you may have to have a few goes with the wax, once you assemble the base have a bit of a play around and you might find some sticky spots, mark where they are and you know where you missed or didnt polish enough :)
to recap.
add the right amount of washers so the base does not wobble at all when assembled. (i only needed to add 1 above the existing teflon centre bearing)
make sure that the motion is free enough that you can tighten up the bolt enough that the base is solid ie. you dont want the bolt loose especially if your interested in the push-to 'mod', plus if your trying to track something and there is slop in the base the scope will move all over the place.
after the polish i just couldnt believe the difference especially observing at higher alt where the problems with az motions really become obvious, my az motion is now as free as my alt movement, almost tracking rather than bumping/nudging. it also does not grab anymore.
anyway i hope someone has a go and reports back!
heres a picture of the wax you will be after:
[img=http://img218.imageshack.us/img218/7238/spa0050cc4.th.jpg] (http://img218.imageshack.us/my.php?image=spa0050cc4.jpg)
Azimuth motion fix.
-----------------
what you need.
1) a few milk bottle washers
2) a tin of 'Gilly Stephenson's Carnauba Polish' (from mitre10)
3) all the neccessary tools to pull your base assembly apart.
4) clean rags/polishing pad/buffer etc...
it doesnt take a lot to work out what your going to be doing from here but ill go through it anyway :)
if you dont know what milk bottle washers are or what to do with them, there is a guide in the 'Projects & Articles' section that you need to check out
anyway you will need to pull the base apart so you can polish the top section where the pads slide, i pulled my base completely apart to make it easier to manage.
once your all set, get into the polishing.. this stuff is absolutely magic, and the finish you get is a HARD coating so it is not acting as a lubricant and wont scratch off easily, it is just filling in all of the rough parts in the laminate, making it silky smooth for the teflon pads to slide on.
be fussy when your doing it, the more time spent polishing the more adjustment you will have later via how tight you do the bolt up.
once youve polished the base up (this part is probably optional) you can add a bevel to the edges of the teflon pads so they glide over rather than grab and scratch into your new waxed surface. (i used a razor blade)
once you put it all back together prepare to be amazed at how smooth it glides, i remember before doing this i could turn the bolt holding the base together, now its tight enough that you cant turn it by hand, holding everything very securely while still allowing silky smooth motion.
you may have to have a few goes with the wax, once you assemble the base have a bit of a play around and you might find some sticky spots, mark where they are and you know where you missed or didnt polish enough :)
to recap.
add the right amount of washers so the base does not wobble at all when assembled. (i only needed to add 1 above the existing teflon centre bearing)
make sure that the motion is free enough that you can tighten up the bolt enough that the base is solid ie. you dont want the bolt loose especially if your interested in the push-to 'mod', plus if your trying to track something and there is slop in the base the scope will move all over the place.
after the polish i just couldnt believe the difference especially observing at higher alt where the problems with az motions really become obvious, my az motion is now as free as my alt movement, almost tracking rather than bumping/nudging. it also does not grab anymore.
anyway i hope someone has a go and reports back!
heres a picture of the wax you will be after:
[img=http://img218.imageshack.us/img218/7238/spa0050cc4.th.jpg] (http://img218.imageshack.us/my.php?image=spa0050cc4.jpg)