Last updated: 11 March 2004
Date: 3/9/04, 06:18 From: terence farrell (Terence.Farrell@unilever.com) I just wanted to share with everyone a parts list for constructing a flexible focuser with off the shelf parts. No drilling/tapping required. I have even included 2 part numbers for different size cables; both colored fluorescent red. Everything listed plus tons more can be found on www.mcmaster.com 1 Each 6412K11 Steel One-Piece Set-Screw Coupling 1/4" Bore, 1/2" OD, 3/4" Length, W/O Keyway $4.44 2 Ft. 9018T31 Fluorescent Vinyl-Coated Wire Rope Galv, 7X7, 1/8"-3/16", 1700 lb Break Strength, Red $0.36 Ft. $0.72 2 Ft. 9018T11 Fluorescent Vinyl-Coated Wire Rope Galv, 7X7, 1/16"-1/8", 480 lb Break Strength, Red $0.21 Ft. $0.42 1 Each 6332K32 Aluminum Control Knob 0.50"Dia X 0.63"H, Knurled Rim, Fits 1/8"Shaft Dia $3.28 Merchandise Total: $8.86 Including shipping charges anyone can manufacture a flexible focuser for about $13 that will take a matter of minutes to assemble. My order was placed today so i'll let you know by Friday how it works. Regards T FarrellAnd:
The parts arrived yesterday. The hardest part of the assembly was cutting through the braided wire. Even including that I had a flexible focuser in a matter of 3 minutes or so. I purchased the ropes in 2 thicknesses but I prefer the 1/8" o.d. myself. For this wire I also used a small piece of Tygon tubing as a "bushing/reducer" (1/4" o.d.-1/8" i.d.) to make the fit in the coupling better. The knob works great because the opening for the wire is already 1/8" and the set screw keeps it snug. I haven't used a commercially available flexible focuser but I can't imagine it works any better than this. Even if you want to use the stock focuser knob you can cut 3 bucks off the cost. The best part of the McMaster-Carr website is that you have a huge array of cables and knobs to choose from and you can also get the coupling in aluminum and stainless also. Shipping was $3.50 so as you can see the math works in anyones favor plus you can customize the focuser to fit your particular needs. Would love to hear from people if they go this route and I can also provides pics if you like. I'm at work so I can't attach them now. Thanks, Terence F
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