skywatcher 200p base smoothness

[crashtestdummy]

i recently purchased a skywatcher 200p dob as my first scope and im wondering if there is anything i can do to make the base rotation smoother as at the moment its a bit sticky even after ive added some copper slip to lessen the friction.any ideas or mod info?am happy with the up down movement just not side to side when the scope up.

[umadog]

This will work very well. ScopeStuff

Alternatively, if you can find a sheet of thin fiberglass, that should be good too.

I know someone who tried the stuff in the link above on an Orion 8" Dob and he was blown away by the improvement. On the other hand, lubricating doesn't work because it does horrible things to the balance between static and dynamic friction.

[RikM]

I just polished the base bearing with Turtlewax at the weekend and it has made a big improvement to the smoothness of the azimuth movement.

I am going to fit discs cut from PP milk bottles around the central bearing as well but I need to drink more milk first as I need about 8 of the things.

[crashtestdummy]

wow thanks for a quick helpful reply.arent certain floor tiles and work surface tops made from from formica?think a trip to b&q/homebase is in order tomorrow

[RikM]

Ebony star is the best but any thin laminate with a pimpled surface should be okay.

[crashtestdummy]

i actually didnt think of car wax,and i have some in the garage.definately going to do some trial and error tomorrow,after cleaning the copper slip off

[jimmyjamjoejoe]

I'm trying to find a decent source of formica at the moment because i'm not gonna pay £25 for a thin ring of plastic countertop...

[RikM]

I'm trying to find a decent source of formica at the moment because i'm not gonna pay £25 for a thin ring of plastic countertop...

My thoughts exactly, hence the car wax and plastic milk bottle washers

[Tiddles]

The milk bottle trick worked for me, I think its about 8 or 10 disks to replace the standard central spacer.

http://stargazerslounge.com/discussions-mounts/172222-skyliner-150p-dobsonion-stiction.html

[umadog]

Formica will work too. I used it on my first build and it was just fine.

I've tried car wax too and found it not to work all that well. The reason is that if the scope sits still for a short period the wax tends to "set" a little and the static friction becomes substantially larger, which is really annoying. I experienced that was with a 12" scope. Perhaps a smaller scope would exhibit this less. Regardless, if you get the right surfaces you won't ever need to wax them because they will intrinsically have the correct friction. Don't forget that waxes need re-application, which is a pain for azimuth, and they will exhibit different characteristics at different temperatures.

[RikM]

I found less is more with the car wax. I put on just a thin sheen onto the board rather than the pads and then buffed it shiny rather than leave a layer on there like a lube. Doesn't seem to stick but I have only been out three times since applying.

[umadog]

If it did stick then you'd have noticed it pretty soon.

[Space Beagle]

I used a similar system on my homemade dobsonian base to the one Rusty Strings used in his base. See this thread for details!

http://stargazerslounge.com/diy-astronomer/98189-building-dob-base.html

It give a really smooth motion if making your own dob base appeals!

Doc

[Tribal-Wolf]

Copperslip is awful stuff and only really for use on high heat areas. You can buy silicon spray which works well and there is also a dry lube that they use to lubricate the drop glass rubber seals on cars so the windows wind down freely.

[crashtestdummy]

copper slip on cars is used to stop rust and metal on metal sticking hence why i thought i would try it as it does have lubricative qualities.only took me 10 mins to try so no real loss it not working and it cleans off easy enough.

[Tribal-Wolf]

It is mainly used on car brakes where heat can speed up corrosion. When I was an apprentice many moons ago it was only ever used on brakes, now I have seen it used on everything from gate hinges to bike chains. As a lubricant is has a pretty poor viscosity rating and if used on plastics can scratch and damage them.

Ideally you want something dry that wont attract dust and grit.

[RikM]

GT85 Silicone bike spray was awful when I tried that.

[johnny diamond]

best thing i came up with was a teflon oven sheet...they can be purchased on ebay for around £4.50 just punched an hole in the middle (teflon being the slippiest thing known to man )

[Poynder]

You could try this method in the following link..http://stargazerslounge.com/discussions-mounts/158264-just-finished-modding-my-dob-base.html

[aussi skywatcher]

I used a 300mm dia lazy susan bearing - its brilliant and very smooth - I used velcro and stuck 4 thick pads of felt to give it some resistance and then used the center bolt to finalise the tension - word of warning, dont lubricate the bearing - it will eventually get dirt in it and it will be notchy until its cleaned out.

Cheers Paul

[UnderTheRain]

I second the teflon vote :-)

[Tribal-Wolf]

GT85 Silicone bike spray was awful when I tried that.

GT85 is similar to WD40, not good when you don't want dirt or grit. This is the sort of stuff I mean

[crashtestdummy]

well i have improved it alot today just by fitting 4 50mm round self adhesive slide glides from b&q on the top of the base(removed the original 3 bushings) and then in the centre i added 5 or 6 old cd's with the original black bushing pushed through and a slightly longer bolt.it now roates alot smoother and small movements are so much easier.not perfect yet though as the centre is a little too high which means there is a slight bit of rock in the base,only when deliberately doing it but its unwanted and i also need a slightly longer and wider centre black bushing to perfect it but all in all i spent £7 for a big improvement so well happy and thanks to everyone for the suggestions.will post some pictures up a bit later.