SVBONY SV181 Rack and Pinion Focuser, 1.25 inch, Newtonian Reflector Focuser for Newtonian Reflector Telescope

Nice upgrade for an old focuser on my 1950’s Newtonian

Fixed all of my alignment issues. My previous focuser that came with my telescope had a lot of slop in it, so always had trouble aligning. This new focuser completely fixed that. I had to make an adapter plate to fit it on my Celestron StarSense dx 130az, but I have had the best views of Jupiter to date in the last 2 days, with very sub-par viewing conditions.

Plus for all metal construction. Curve on plate is for a 5 inch tube. I have a 4 1/2 inch tube and needed to make a spacer to fill the gap between the tube and the focused. The focus adjuster was very loose and wobbly. Strap that holds the adjuster knob shaft is poorly designed and doesn’t do the job properly. I was able to tighten in up by bending the straps so it pushes the shaft closer to the gear. The strap is made of thin steel and this should have been done at the factory or a better tighter fitting part made. Once tightened it seemed to work acceptable but it might loosen again over time. Tension locking screw on adjuster is a nice feature that OEM adjusters don't have. Good product with some flaws which can be fixed with a little effort. The draw tube and gears are all metal which is nice.

Decent quality but the sizes can be problematic if doing a restoration. The biggest problem is the 3" draw tube. It project WAY into the light path on a 6" f8 Newtonian. It certainly was unusable for my application.

Works great, it operate really smooth and functions well with my telescope.

Well crafted perfect for telescope project , lightweight, great smooth operation!

Prime day purchase. About 5 hours of effort to modify for my DIY 80mm objective, 520 mm refractor telescope. Focuser has precise helical brass gears, anti-friction pads for aluminum draw tube stability, tube position tension/lock screw, all metal construction. Total play is minimum. Gear ratio should be good at least up to 200x. Very stable for 1.25 optical eyepieces or to focus into camera. Enjoying the great value. Would be great to have a standardized 2.5 inch tube as an option for refractor. FYI -2 inch tube extension is not big enough for both linear gear and draw tube.

Good cheep focuser for modifications. Iv'e added five photos. First there are photos with a ruler next to the focuser so you can see how much travel it has. With the focuser racked in all the way, it blocks light coming into the telescope. I don't need that much travel. I disassembled the focuser (third photo), cut 40 mm off the focuser tube and rack, and put it back together. I filled some of the rack threads with solder and drilled and countersunk a new hole for the screw. The screw threads are 2 mm x 0.4 mm. I got the tread tap off amazon. I also ground off the bottom of the focuser with an angle grinder and sand paper to make the focuser fit flat on my telescope box. I could have put some putty under the arch, but I needed the focuser to sit very low. Finally a photo of the old focuser and this new one on the telescope box. I will put the camera on the old focuser, and a cross hair recital eyepiece in the new one for guiding during photography. Also I want to mention that there are three little allen screws on one side around the silver thumbscrew. Two of them press a piece of plastic against the draw tube to tighten it up. The third keeps the plastic piece from falling out.