FTF3545 More detail:

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The gaping maw of the FTF3545 drawtube exceeds the nominal 3.5" spec by coming in at a whopping 3.7" and 109mm outside diameter. A single stop screw has to clear backplates or any internal baffles.

The drawtube itself is furnished with 12 baffles with a low reflection thread like surface and matt black finish. Cameras are notorious for showing up matt black as grey. Particularly when using flash.

 

The Baader 3.5 to 2" Clicklock, drawtube, end cap is matt black rather than the gloss of Starlight Instruments own. It weighs quite a bit on its own thanks to its substantial thickness.

I really like the effortless locking onto any inserted 2" device. Achieved simply by rotation of the collar with the aid of the projecting lever. Somebody was kind enough to give the lever a smoothly rounded end. So habitual eyepiece swappers don't get blisters.

I still feel the Baader matches up to the overall FT standard on finish. Though at considerable expense. Starlight don't do a 2" collect style, adapter fitting for the 3.5". Just a normal three screw, compression band adapter. With all the extensions and fittings in my H-alpha set-up, I had no desire to add yet more projecting thumbscrews to the mix.

Note the three tiny grub screws intended to lock the Clicklock collar onto the FTF  drawtube. A thoughtful bit of extra insurance for such a large diameter fitting. Where applied unlocking torque, particularly when wearing gloves, might well begin to unscrew the whole collar.

The Feather Touch rack is rather fine, helically [diagonally] cut, thin and flat. Making for low gears with a matching, relatively small diameter, helical pinion.

It looks as if it is manufactured in long lengths and then cut to match the needs of each model of the FT focuser.  A practical means and arguably more accurate and perhaps at lower cost, than making short sections like most [cheaper] rack and pinion focusers.

The shoulders of the rack are neatly rounded and give absolutely no sense of "cutting corners." The rack is lightly oiled which explains my fingermarks all over the focuser. A blue tape was applied to the rack to protect window shoppers at the dealers. Or perhaps to keep the focuser clean while being fitted to an OTA. I didn't bother to polish the focuser before snapping away with my camera.

The vital connection between the big focuser and its OTA: 

A cone is provided for centring as the big, finely threaded collar is screwed onto a suitable, Feather Touch OTA/base adapter. These adapters are made by Starlight in a whole range to suit many commercial [mostly APO] refractor OTAs. 

It must be admitted that the very high prices of these adapters put me right off buying one. More so, because none suited my precise needs for fitting to the flat backplate of my DIY 7" f/12 refractor.

These rather simple, threaded adapters cost nearly half the price of the complete focuser. Which makes no sense at all to me. There is far more work and materials involved in producing the whole focuser. While the adapters are readily mass produced on CNC machines. I worked on CNC production myself so know something of the work involved. 

I ended up ordering a hefty, custom made ring from Teleskop-Express/Service. They say it will be made specifically to fit the FTF3545 base collar. I can easily manage the fitting of the custom ring to a sturdy backplate on my vintage lathe. Though I baulked at cutting the large and fine threads involved.

Click on any image for an enlargement. 

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