Ebony Star dob bearings - some queries

[sheridangj]

Hi folks,

I'm planning on upgrading my SW 200P dob bearings using ebony star. Previous threads have mentioned that Telescope Service sell pre-cut rings but searching for 'ebony star' on their website seems to draw a blank now.

I've found this website advertising Ebony Star/PTFE in various sizes: http://www.gerdneumann.net/english/instrument-building-parts-teile-fuer-den-fernrohrbau/lagermaterial-fur-dobsons-ebony-star-und-teflon-ptfe-bearings.html.

I'm not sure exactly what to get for the standard 52cm SW base however - I assume the measurements shown indicate the diameter if the inner and outer edges of the ring which would suggest that only the 30cm disk would fit this base. Can anyone confirm this and if so, would the 30cm disk be big enough? If not, does anyone know of a supplier (preferably in Europe but USA if necessary) who could supply the correct size ring?

My other query relates to the altitude bearings - they seem fairly smooth as they are so are they worth upgrading? If so, what exactly to I need to buy/do to upgrade them?

Many thanks.

Gav

[johninderby]

Telescope Service still does the sheets of ebonystar.

http://www.teleskop-express.de/shop/product_info.php/language/de/info/p2472_.html

They only have two of the larger sizes of the pre-cut rings left now.

John

[jimmyjamjoejoe]

30cm should be fine, i used a 30cm lazy susan and it just fit around the screws through the bottom board etc.

[ollypenrice]

Use Turtle Wax to polish it. I find it's the best of the lot and some others are a disaster.

Olly