safe way to load the OTA on the MACH2
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Andrea Lucchetti
Hello,
I am not new to the hobby but my current OTA makes the set up phase not easy at all. the diameter is 270mm and weight around 19 kg, and I don't feel confident in loading the telescope by myself on the mount. I wonder if someone has perfectioned a style for the move. :-) I use the AP DoveDV10 saddle plate, open the lockers, put the bar flat and on the left, close the lockers. I load the scope in PARK3 position. previously I used to slide the telescope from behind ( a TEC 140) but now this seems impossible. I know it sounds like a joke but I don't like to be dependent on other people for the task. if you know a trick , please share it. Thank you Andrea
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Mine's not as heavy as yours, but I find loading much easier on park 2. With the scope pointing sideways, I get the bottom edge of the D plate into the bottom edge of the saddle, then tilt it back so the plates are fully together, slide it left or right for where I know the balance point is, and then tighten it down.
My scope is mounted on the D plate with rings. I have a vixen bar on top of rings that I use as a handle, and enough space under the rings that I can get my other hand between the scope tube and the mount plate.
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Jeffc
I saw a video once where a large OTA was mounted by putting the OTA vertical on a tall chair next to the mount, and then bringing the DEC axis to a vertical position to mate with the OTA.
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I cannot find the video, but it goes something like this: 1) A chair (or table, or custom stand) is positioned next to the mount directly east or west… it will require some alignment that will become clear in a moment. 2) The OTA , with lens cap on, is placed on the chair / stand etc pointing down. Eg if the OTA is a SCT then the visual back is sticking up. Likely a strap should be used to prevent the OTA from falling. 3) The OTA is positioned so the dovetail is facing the mount. 4) The mount RA axis is positioned horizontal with the DEC axis dovetail on the side where the OTA is now positioned. At this point I think you don’t want any counterweight. 5) The DEC axis is then rotated vertical to match up with the OTA dovetail. 6) At this point some alignment, ie moving the chair/table will likely be required…. Once aligned with the saddle, the dovetail saddle can then be clamped, and counterweights added, OTA strap removed, and chair/stand removed. I have not tried this approach. I also have a rather heavy OTA - 300mm diameter and weighs about 18kg. This OTA has a handle on the back such that I can use one hand under on the dovetail and the other hand on the handle to lift the OTA to just above my shoulders and slide the dovetail in. Getting the OTA off in the dark is also a bit scary. It is borderline weigh for me, and I would prefer a different approach — possibly one with less “drama”. -Jeff
On Dec 31, 2020, at 8:04 AM, Andrea Lucchetti <andlucchett@...> wrote:
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W Hilmo
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From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Jeffc
Sent: Thursday, December 31, 2020 9:10 AM To: main@ap-gto.groups.io Subject: Re: [ap-gto] safe way to load the OTA on the MACH2
I saw a video once where a large OTA was mounted by putting the OTA vertical on a tall chair next to the mount, and then bringing the DEC axis to a vertical position to mate with the OTA.
I cannot find the video, but it goes something like this:
1) A chair (or table, or custom stand) is positioned next to the mount directly east or west… it will require some alignment that will become clear in a moment.
2) The OTA , with lens cap on, is placed on the chair / stand etc pointing down. Eg if the OTA is a SCT then the visual back is sticking up. Likely a strap should be used to prevent the OTA from falling.
3) The OTA is positioned so the dovetail is facing the mount.
4) The mount RA axis is positioned horizontal with the DEC axis dovetail on the side where the OTA is now positioned. At this point I think you don’t want any counterweight.
5) The DEC axis is then rotated vertical to match up with the OTA dovetail.
6) At this point some alignment, ie moving the chair/table will likely be required…. Once aligned with the saddle, the dovetail saddle can then be clamped, and counterweights added, OTA strap removed, and chair/stand removed. Getting the OTA off in the dark is also a bit scary. It is borderline weigh for me, and I would prefer a different approach — possibly one with less “drama”.
-Jeff
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Roland Christen
I always put the rings on the mount, open them and then place the scope into the rings. This is done in Park2 position. I can load my 155 and 160EDF refractors that way by myself, and I'm not a strong man weight lifter.
I would NEVER load any refractor with the dovetail and rings attached to the scope. It's asking for disaster.
Roland
-----Original Message-----
From: Andrea Lucchetti <andlucchett@...> To: main@ap-gto.groups.io Sent: Thu, Dec 31, 2020 10:04 am Subject: [ap-gto] safe way to load the OTA on the MACH2 Hello,
I am not new to the hobby but my current OTA makes the set up phase not easy at all. the diameter is 270mm and weight around 19 kg, and I don't feel confident in loading the telescope by myself on the mount. I wonder if someone has perfectioned a style for the move. :-) I use the AP DoveDV10 saddle plate, open the lockers, put the bar flat and on the left, close the lockers. I load the scope in PARK3 position. previously I used to slide the telescope from behind ( a TEC 140) but now this seems impossible. I know it sounds like a joke but I don't like to be dependent on other people for the task. if you know a trick , please share it. Thank you Andrea -- Roland Christen Astro-Physics
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Ted Mickle
Check out this video - I believe it’s the one you’re looking for:
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https://youtu.be/IwVg1M6bURI Dr Ted Mickle Colonel, U.S. Air Force (Ret)
On Dec 31, 2020, at 11:09, Jeffc <jeffcrilly@...> wrote:
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Worsel
Andrea
I use the method shown in the video that Wayne and Ted list to load a 25 kg OTA on an 1100 mount. I built a wooden table (sturdier than a step stool in the video!) that is at the correct height so it fits snugly under the OTA when rotated to the 'unload' position. In this fashion, the OTA is never suspended even a few inches without support as the dovetail clamps are loosened. Bryan
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Here are some rambling musings of an equipment addict and observatory engineer. FWIW. All of my OTA's have permanent dovetail bars on them. Additionally, all of them also have handles or bars on top of the OTA. This extra gripping spot really helps me to get OTA's on and off of mounts. Sometimes I have had to machine the handle or bar myself if a commercial solution wasn't available. I NEVER take any of my OTA's out of the rings, if it has them. My AP 130 and 92 both have handles on top and never come out of their rings. I had a custom case made to hold my 130 in its rings and handle, along with room lengthwise for a camera and such too. I am not lucky enough to have a BIG AP refractor or I might be doing it the way Roland does his. Fortunately (unfortunately?) my 130 and 92 aren't very heavy. As for my C14, C11 (x2), C9.25, C8, M16, M10, M5, N10 and RC20, only the C14, M16, N10 and RC20 offer much challenge. The others are pretty-easy and don't require much strength. I tried the Rayox "automatic engaging" saddle bracket with my C14 and found it even more difficult to use than a regular AP D-style dovetail bracket. I just couldn't hold the entire weight of a C14 steady enough (video method one) to carefully line it up with the darn bracket. I tried both Park2 and Park 3 and it was just as impossible either way. The Rayox dovetail bracket now lives in my spare parts piles. What helps the most is having that long, grippable bar on top of the C14. The N10 (10" f3.8 RFT Newt in a fiberglass tube with custom, permanent rotating rings on a long D-bar) also benefits from a long bar (handle) on top. I really, really don't like the old-style Losmandy dovetail bracket that requires sliding the OTA dovetail bars in and out from the end. I have several in my spare parts piles. Free to anyone who wants them. My G11 currently has a Chinese combination D-V dovetail bracket on it. Eventually I will put an AP D-style dovetail bracket on it. I really prefer combination D-V brackets on my mounts. I am always testing or repairing different OTA's and having a combination D-V saddle bracket is very handy. Having the bracket locks independent from each other is much better than having them combined. Example is the comparison between the ADM brackets (combined) and the AP brackets (independent). IMO, it takes a lot less human-force on the knobs to securely lock an OTA in an AP bracket than it does an ADM bracket. Whenever I have had to put an OTA onto an ADM bracket, I have always used the special ADM wrench to really-tighten the knobs. Not very convenient. The AP locks feel significantly more secure. On my M16 (Meade LX200GPS-16), I use a hitch-crane (hitch-hoist/game-hoist from Cabella's) to assemble and disassemble the scope by myself. Required adding a dovetail bar to the top of the OTA with a threaded hole in the top bar for a stainless eye bolt. Works well and feels very secure and safe. I put a bar on the bottom too. Handy for counterweights, Polemasters, dome-cams, etc. I use the same hitch-crane on my RC20. RC20 currently under re-construction and being moved to a custom Alt-Az mount with optical rotator. Will probably still need the hitch-crane when I am done. Unless I install it in an observatory. I am 62 and My C14 is getting heavier every year. Currently I am using video-method-1 but eventually will probably have to move to video-method-2. Or extend the height of my hitch-crane. I have tried video-method-2 in the past and it was a real PITA to handle. Everything depends on the quality, size and stability of the astro-chair involved. The bigger, probably the better and more stable. A better approach might be a Lymax electric lifting column (Pier-Tech style) with four fold-out, locking, 8" wheeled, legs on the bottom and an OTA-diameter, cup-style base on top. In observatories, adding an eyebolt to a strong point in a roll-off roof is handy for a lifting point, if your structure can handle the weight of your various scope parts. Ash domes are super-strong and I often drill a hole into the center tab on the bottom of the upper shutter and put a stainless-steel clevis through the drilled hole for a lifting point. Rotating the dome and running the upper shutter up and down allows me to get the lifting point just about anywhere over the scope and the observatory floor. Sometimes I use an electric winch and other times a simple come-along. Instant, one-person observatory crane! I hope this helps. "My advice is always free and worth every penny!" Observatory Engineer Summit Kinetics Waikoloa, Hawaii
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On Thu, Dec 31, 2020 at 12:17 PM, Roland Christen wrote:
I would NEVER load any refractor with the dovetail and rings attached to the scope. It's asking for disaster.I'm curious what kind of disaster you have in mind. I haven't tried it the way you suggest, but it seems to me that it's much more unwieldy trying to manipulate my TOA-130 without the rings and plates attached. That rig is about 36 lbs all in, with the rings and plate only about 5 of it. Given the front heaviness of the TOA and lack of places to grip a long smooth cylinder I think I'd be much more likely to have an accident with the rings, plate, and handle removed. At 155 or 160 it's a different story.
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Roland Christen
I just grab the front and rear of the telescope tube and lift it into the open rings. I can then move the scope back and forth for balance as needed, and then snap the rings shut. Easy-peasy.
Rolando
-----Original Message-----
From: Xentex <michael@...> To: main@ap-gto.groups.io Sent: Thu, Dec 31, 2020 12:43 pm Subject: Re: [ap-gto] safe way to load the OTA on the MACH2 On Thu, Dec 31, 2020 at 12:17 PM, Roland Christen wrote:
I would NEVER load any refractor with the dovetail and rings attached to the scope. It's asking for disaster.I'm curious what kind of disaster you have in mind. I haven't tried it the way you suggest, but it seems to me that it's much more unwieldy trying to manipulate my TOA-130 without the rings and plates attached. That rig is about 36 lbs all in, with the rings and plate only about 5 of it. Given the front heaviness of the TOA and lack of places to grip a long smooth cylinder I think I'd be much more likely to have an accident with the rings, plate, and handle removed. At 155 or 160 it's a different story. -- Roland Christen Astro-Physics
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I used to mount my 180 EDT (OTA weight 35 pounds) with the mount in Park 3 until I read Roland's suggestion to do this from Park 2. The Park 2 option is WAY better !
If you have a bad back like me you might want to consider getting some kind of ladder or step stool. I got this one from McMaster. It is pricey ($315.00) but it has a 450 lb capacity, you can roll it right up to the pier, and it won't tip over. I also have two 90 cm long nylon slings that I wrap around the OTA to use as carrying handles when mounting and dismounting the OTA. 
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I see. That makes sense if you're fully breaking down the rig.
I don't do visual, and my imaging trains almost never leave my scopes. I don't buy anything I can't carry fully assembled in one hand while opening and closing a door with the other. Making it through the house and doors is generally trickier than getting it up onto the mount. Right now 130mm is about my limit for that.
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Jeff B
Except for my really heavy scopes, I always load OTAs onto the mount in the Park 2 position. With my smaller, light scopes, like my AP 130, TEC 140ED and short achromats, where I can see exactly how they fit into the saddle's tip in dovetail , I load them with the plate dovetail attached. With the fatter OTAs like my C11, TEC 160ED and AP 178, where I cannot easily see both sides of the dovetail, I first load the dovetail plate with rings attached, then lift the OTA into the rings. For my big butt newts and my TEC 200ED, I walk the OTAs, with their dovetail plates attached, into the saddle with the dovetail pointed straight up and down with the dec shaft propped up, somewhat level with the ground. Doing the 200ED this way, which is permanently mounted under a Telegizmos 365 cover, requires me to erect a platform about 4 foot off of the ground, next to the pier, place the OTA sideways on that, get up onto the platform, raise the OTA vertical, walk it into the saddle, balance it, put it into Park 3, cover it (using a ladder) then finally take an Aleve...or two and recover for the next day...or two. Jeff
On Thu, Dec 31, 2020 at 3:00 PM Xentex <michael@...> wrote: I see. That makes sense if you're fully breaking down the rig.
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Joe Zeglinski
Hi,
I have always used PARK-2, the safest and easiest
position from which to mount or dismount my RC-14.5 inch truss OTA – when
I have to. I also use that position with a much lighter OTA, such as
a Questar-7 MAK.
However, although I fully agree with all the comments
about the position, and especially use of OTA safety handles as Chris
mentioned, having to lift it unassisted, I still don’t trust my grip even
on the lighter scope. An OTA can become VERY slippery, after a night’s session,
when slicked with dew or ice crystals. Similarly, even though I can still
“manage” gripping maybe an 80 lb. OTA, at my age, I always like a bit of
insurance, especially when standing on a step-stool. When I need to attach or remove the
OTA, I always tie (or “safety-clip”), a rope around its ends, or OTA
ring handles if it has them, and hang the loop about my neck – just in
case. If I accidentally trip or fall, I
have health coverage – but the scope is uninsured with possibly a long AP
replacement “wait-list”, so I would rather be the one cushioning its fall.
Besides, I always feel that some day it might slip from my hands, or ice cold
fingers, and a belt or a rope loop, gives it a “fall-back”
position. With your neck & shoulders providing that extra
“third lifting balance point”, you also won’t strain your arms, whose
unexpected spasm might drop it. Taking a stance on the ground like a
weight-lifter, I can then deftly “lift & snap” the OTA safely
into the waiting D-Plate carrier, holding it there at PARK-2, braced with one
hand as I quickly secure the lock knobs. If my fingers should fumble anytime
during the process, that neck belt is still there, until the OTA is safely
on the mount, or down inside its travel case. Joe Z.
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Joe Zeglinski
On the subject of OTA safety ... I would
strongly suggest you be certain to have a wide head bolt, wider than the D-plate
center groove – such as a 1/4-20 camera equipment lock nut – screwed UNDER the
D-Plate. It would be personally
embarrassing, or even dangerous for the OTA, if it weren’t secured
tightly enough in the saddle, and it suddenly slid down, right off the saddle to
the ground as the mount slewed to an upward position. At least that “safety-stop
bolt” would have the D-Plate slam a short distance into the end of the saddle,
rather than completely off to the ground.
I wonder how many of us don’t have that safety-stop,
or know that there should be one there. Joe Z.
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That is one thing I neglected to mention. A safety stop on the upper-end of the dovetail bar. Thanks for the reminder Joe. I like to use the Losmandy DVA D-style ring bases (or an ADM DPA-D + "Rosette Knob Hand Tool") as a quick-on and quick-off safety stop. You can even put it at the right spot that gets the OTA balancing right the first time without further adjustment. They also provide a big edge to rest the OTA weight on while you take one hand to crank the bracket knobs. Make sure to crank them down securely so a sliding scope won't knock it right off the end of a dovetail bar. I hope this helps. "My advice is always free and worth every penny!" Observatory Engineer Summit Kinetics Waikoloa, Hawaii
On Thu, Dec 31, 2020 at 12:55 PM Joe Zeglinski <J.Zeglinski@...> wrote:
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Jeffc
On Dec 31, 2020, at 9:16 AM, W Hilmo <y.groups@...> wrote:
Yes.. I think so.
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Hi,
toggle quoted messageShow quoted text
this part from Baader Planetarium helps me to load my 16 kg OTA on my AP1600 safe. I use the park position 2. Grüsse Konstantin v. Poschinger Hammerichstr. 5 22605 Hamburg 040/8805747 0171/1983476 
Am 01.01.2021 um 06:38 schrieb Jeffc <jeffcrilly@...>:
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Thank you Roland and others, it seems that Park2 could be the way to go for me.
In my case three things worries me: -my latitude is 42 deg, but that it shouldn't be a problem -my rings are not very quick to lock: I have to put on the half ring and tighten the screws -the scope will be unbalanced in DEC without the imaging train and guide scope Roland, Do you think the DEc friction will manage that unbalance for the time required to lock the rings? or is this going to stress the mount too much? I think I can find a balance point for this unloaded configuration, load the OTA in this configuration and slide the OTA back during final balance (it is a newton). Thank you and Happy New Year Andrea
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Roland Christen
Do you think the DEc friction will manage that unbalance for the time required to lock the rings? No problem holding large unbalance. You can tighten the clutch knobs very hard with an Allen wrench.
Roland
-----Original Message-----
From: Andrea Lucchetti <andlucchett@...> To: main@ap-gto.groups.io Sent: Fri, Jan 1, 2021 6:03 am Subject: Re: [ap-gto] safe way to load the OTA on the MACH2 Thank you,
in my case three things worries me: -my latitude is 42 deg, but that it shouldn't be a problem -my rings are not very quick to lock: I have to put on the half ring and tighten the screws -the scope will be unbalanced in DEC without the imaging train and guide scope Do you think the DEc friction will manage that unbalance for the time required to lock the rings? or is this going to stress the mount too much? I think I can find a balance point for this unloaded configuration, load the OTA in this configuration and slide the OTA back during final balance (it is a newton). Thank you, Andrea -- Roland Christen Astro-Physics
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