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Just bought a lightly used EQ1 head for $35 shipped. I figured, why not, circles looked clean and it should be able to hold my ST80 and 90mm Mak, I hope. This will most likely be a plaything until I buy a "real" EQ mount.
Anyway, I'll need a counterweight shaft for it. Is there a standard size or should I just buy a threaded rod from HoPo and stick a mess of steel washers on it?
Thanks.
============================================================================= Man... That's some icky-tasting stuff! =============================================================================
AT50, AT72EDII, ST80, ST102; Scopetech Zero, AZ-GTi, AZ Pronto; Innorel RT90C, Oberwerk 5000; Orion Giantview 15x70s, Vortex 8x42s, Navy surplus 7x50s, Nikon 10x50s
If nobody else responds by Sunday I will be back home then and can measure one for you.
Gabrielle See Far Sticks: Elita 103/1575, AOM FLT 105/1000, Bresser 127/1200 BV, Nočný stopár 152/1200, Vyrobené doma 70/700, Stellarvue NHNG DX 80/552, TAL RS 100/1000, Vixen SD115s/885 EQ: TAL MT-1, Vixen SXP, SXP2, AXJ, AXD Az/Alt: AYO Digi II, Stellarvue M2C, Argo Navis encoders on both Tripods: Berlebach Planet (2), Uni 28 Astro, Report 372, TAL factory maple, Vixen ASG-CB90, Vixen AXD-TR102 Diagonals: Astro-Physics, Baader Amici, Baader Herschel, iStar Blue, Stellarvue DX, Tak prism, TAL, Vixen Eyepieces: Antares to Zeiss (1000101) The only culture I have is from yogurt
pakarinen wrote: ↑Thu Jun 18, 2020 12:50 pm
Just bought a lightly used EQ1 head for $35 shipped. I figured, why not, circles looked clean and it should be able to hold my ST80 and 90mm Mak, I hope. This will most likely be a plaything until I buy a "real" EQ mount.
Anyway, I'll need a counterweight shaft for it. Is there a standard size or should I just buy a threaded rod from HoPo and stick a mess of steel washers on it?
Thanks.
I've seen the mounts but don't have one so can't measure it for you.
If the payload is very light, a bunch of washers might work if you can find a threaded rod that screws in. But I think an ST80 weighs in a bit over 1kg.
The EQ1 is a small mount. You'd be much better off using a bigger counterweight closer to the top of the counterweight shaft than using a lighter counterweight bouncing on the far end of the shaft.
If you can use a threaded rod, you could also pay an engineering firm to cut off a suitable piece of steel shaft, drill and thread it with the appropriate tap. Then you can just spin it up and down the shaft to adjust the balance. The weight of the counterweight will depend upon the relative distance of the OTA and the shaft from the polar axis. If the OTA is 1kg and the OTA is half the distance of the counterweight, you'll need at least 500g counterweight. From the table, that's a 20mm thick disk of 63mm(2.5in) steel round.
cheers
Joe
Amateur astronomer since 1978...................Web site :http://joe-cali.com/ Scopes: ATM 18" Dob, Vixen VC200L, ATM 6"f7, Stellarvue 102ED, Saxon ED80, WO M70 ED, Orion 102 Maksutov, ST80. Mounts: Takahashi EM-200, iOptron iEQ45, Push dobsonian with Nexus DSC, three homemade EQ's. Eyepieces: TV Naglers 31, 17, 12, 7; Denkmeier D21 & D14; Pentax XW10, XW5, Unitron 40mm Kellner, Meade Or 25,12 Cameras : Pentax K1, K5, K01, K10D / VIDEO CAMS : TacosBD, Lihmsec. Cam/guider/controllers: Lacerta MGEN 3, SW Synguider, Simulation Curriculum SkyFi 3+Sky safari Memberships Astronomical Association of Queensland; RASNZ Occultations Section; Single Exposure Milky Way Facebook Group (Moderator) (12k members), The Sky Searchers (moderator)
Seller informed me that he discovered the mount I was going to buy had a strange dovetail saddle, so he offered me a Celestron EQ1. Maybe I should post in the C-tron subforum instead.
============================================================================= Man... That's some icky-tasting stuff! =============================================================================
AT50, AT72EDII, ST80, ST102; Scopetech Zero, AZ-GTi, AZ Pronto; Innorel RT90C, Oberwerk 5000; Orion Giantview 15x70s, Vortex 8x42s, Navy surplus 7x50s, Nikon 10x50s
They are all pretty much the same, I will be home to take measurements later tonight 05:30 here now.
Gabrielle See Far Sticks: Elita 103/1575, AOM FLT 105/1000, Bresser 127/1200 BV, Nočný stopár 152/1200, Vyrobené doma 70/700, Stellarvue NHNG DX 80/552, TAL RS 100/1000, Vixen SD115s/885 EQ: TAL MT-1, Vixen SXP, SXP2, AXJ, AXD Az/Alt: AYO Digi II, Stellarvue M2C, Argo Navis encoders on both Tripods: Berlebach Planet (2), Uni 28 Astro, Report 372, TAL factory maple, Vixen ASG-CB90, Vixen AXD-TR102 Diagonals: Astro-Physics, Baader Amici, Baader Herschel, iStar Blue, Stellarvue DX, Tak prism, TAL, Vixen Eyepieces: Antares to Zeiss (1000101) The only culture I have is from yogurt