hcsceo
member
Reged: 10/14/09
Posts: 30
Loc: Austin, TX
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I have a SVP mount which I never got a tripod for. I do have it working on a camera tripod of mine but am planning to find a permanant solution. I want to use a surveyor tripod off Ebay with a CG-5 to surveyor tripod adapter from Universal Astronomics. None of the surveyor tripods come with spreaders. My feeling is this should be a much sturdier mount than the standard SVP tripod but should I worry about not having a spreader? Any help would be appreciated.
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Steve
In the Texas Hill Country!
Celestron C6-N 750mm F5, Skyview Pro Mount
Proudly Classified as a NEWB
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rmollise
Post Laureate
Reged: 07/06/07
Posts: 4575
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Quote:
I have a SVP mount which I never got a tripod for. I do have it working on a camera tripod of mine but am planning to find a permanant solution. I want to use a surveyor tripod off Ebay with a CG-5 to surveyor tripod adapter from Universal Astronomics. None of the surveyor tripods come with spreaders. My feeling is this should be a much sturdier mount than the standard SVP tripod but should I worry about not having a spreader? Any help would be appreciated.
Yes, your feeling is correct.
A spreader is pretty easy to make out of a disk of plywood or whatever.
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Uncle Rod
Rod's New Book:
Choosing and Using a New CAT
Available now!
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letimotif
No Complaints
Reged: 05/20/07
Posts: 2014
Loc: Far Flung Isles of Langerhans
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Like Rod said. Think about it this way: a surveyor's tripod is sturdy, but it typically won't be weighed down with as much junk, err specialized tools, such as you will have mounted on that CG5.
Cheap to make, and good insurance against those "Whoopsie" moments that happen in the dark.
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Ah, but a man's reach should exceed his grasp, or what's a Heaven for?
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Doug76
Postmaster
Reged: 12/05/07
Posts: 5554
Loc: SE Louisiana, future Texan
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What Unk said.
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Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors, 50mm-150mm
1 apo refractor, 90mm
1 SCT, 8 inch
UO Abbe Volcano Tops
Faworski Ortho's
Panoptic 24mm
Carton 100mm f/13 under construction 
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Al Canarelli
Carpal Tunnel
Reged: 12/06/07
Posts: 2611
Loc: Central New Jersey
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I have a SVP mount which I never got a tripod for. I do have it working on a camera tripod of mine but am planning to find a permanant solution. I want to use a surveyor tripod off Ebay with a CG-5 to surveyor tripod adapter from Universal Astronomics. None of the surveyor tripods come with spreaders. My feeling is this should be a much sturdier mount than the standard SVP tripod but should I worry about not having a spreader? Any help would be appreciated.
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By "spreader" you must mean the plate and clamping knob which puts tension on the legs. This is very important, as nothing adds rigidity to the tripod as this device. I've made and sold tripods to the astronomy community for about a decade and can tell you that this device alone would make one of those old aluminum tripods that use to come out of China almost usable.
If you would like to add such a device to your surveyor tripod, rest assured that it will do wonders for the tripod. You will need a 10M threaded SS rod, a few knobs and a hardwood or aluminum plate cut to size and you're good to go. You can buy everything you need at reasonable cost for www.mcmaster-carr.com
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Phil Frederick
scholastic sledgehammer
Reged: 12/19/05
Posts: 844
Loc: Seattle, WA & La Paz MX
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Quote:
I have a SVP mount which I never got a tripod for. I do have it working on a camera tripod of mine but am planning to find a permanant solution. I want to use a surveyor tripod off Ebay with a CG-5 to surveyor tripod adapter from Universal Astronomics. None of the surveyor tripods come with spreaders. My feeling is this should be a much sturdier mount than the standard SVP tripod but should I worry about not having a spreader? Any help would be appreciated.
============================================================
By "spreader" you must mean the plate and clamping knob which puts tension on the legs. This is very important, as nothing adds rigidity to the tripod as this device. I've made and sold tripods to the astronomy community for about a decade and can tell you that this device alone would make one of those old aluminum tripods that use to come out of China almost usable.
If you would like to add such a device to your surveyor tripod, rest assured that it will do wonders for the tripod. You will need a 10M threaded SS rod, a few knobs and a hardwood or aluminum plate cut to size and you're good to go. You can buy everything you need at reasonable cost for www.mcmaster-carr.com
Absolutely agree with Al on on the "locker" as I have on previous threads.
A speader is great in that it keeps the tripod from spreading out and ultimately collapsing as a result of the legs overpreading. The solution I recommend for this problem is either a spreader similar to the Orion spreader on the Astroview, or the Oberwerk spreader that's modified. An alternative to this is to attach a chain spreader restrainer which is very easy to do and keeps the legs from overspreading.
The above solutions do not really add to the stability of the tripod however. If you were to use the spreaders discussed above and added a tray that clamped to the spreader arms it would help. However, part of the stability problem is that where the arms attach to the tripod legs, it's sloppy. This connection need to be firmed up with a better solid hinge connection (done that!). Don't allow any slop in the connection between the speader bar and the legs. THAT will make a difference.
Probably one of the best solutions to tripod stability is (as Al has suggested--and I concurr) is to ad a long 3/8" or M10 rod below the tripod head and fabricate a tray that sucks up aginst the tripod legs with a clamping knob and creates REAL stabilty in the tripod/mount. This is similar to what Orion as in the SVP (and others) do to lock the legs in and eliminate movement and reduce vibration.
Seems to me that many tripod/mount providers don't pay attention to the head/mount attachment and don't provide solid apreader connections that prevent movement of the legs (however, SOME do a great job--they just cost more!).
But a good tripod REALLY does make a difference! 
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Phil
Intes M500 MCT (Teton Mods)
Stellarvue SV115EDT
Stellarvue SVR70ED Raptor
Orion ST80 f/5 w/Crayford
SV F50 Sparrowhawk
SV F60 Biggerhawk
Tak Teeguls, SV MG, SV Stablelock tripod, TV Gibraltar tripod, a rebuilt TV Gibraltar tripod with fixed Walnut/Oak legs, M1 on Bogen475
... Naglers, Panoptics, Stratus'
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Adrian Lopez
sage
Reged: 10/22/08
Posts: 269
Loc: Puerto Rico
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Quote:
A speader is great in that it keeps the tripod from spreading out and ultimately collapsing as a result of the legs overpreading.
I'm trying to figure out how does the spreader keep the legs from spreading any further, but I'm just not seeing it. Tension on the clamping knob pushes the spreader upwards which in turn causes the legs to spread further out. This prevents the legs from closing together but it doesn't prevent them from spreading out even further. If the legs didn't have a stop at the hinge they would continue to spread beyond the spot where they contact the plate, like a ballerina doing a split.
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Celestron Omni XLT 120 (f/8.3) Refractor
William Optics 1.25" Dielectric Diagonal
Celestron 4, 6, 9, 15, 25, and 32mm EPs
Nikon Action Extreme 8x40 Binoculars
Canon Digital Rebel XT
RA Sweep Calculator (find objects without GoTo)
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Phil Frederick
scholastic sledgehammer
Reged: 12/19/05
Posts: 844
Loc: Seattle, WA & La Paz MX
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Actually, we're talking about two different things here.
A 'leg locker' is attached to the tripod head with a long bolt and sucks up against the legs with a clamping knob. In order to be effective it's also necessary to have one of two things: 1) the top of the tripod legs must have a hard 'stop' where they attach to the tripod hub which allows them to splay out only so far(this is the method used on the SVP and CG5 tripods) or 2) it's necessary to have a 'spreader' which is mounted lower down on the legs and hinged in such a way that the legs can be folded up easily but when the legs are splayed out the spreader prevents them from splaying beyond a certain point.
So with either of these senarios the tripod legs are splayed out to their maximum because of either the hard stops or the spreader and by adding the leg locker, upward and outward pressure is applied to the pyramidal structure which further stabilizes the tripod.
Did I explain this ok??? 
Phil
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Phil
Intes M500 MCT (Teton Mods)
Stellarvue SV115EDT
Stellarvue SVR70ED Raptor
Orion ST80 f/5 w/Crayford
SV F50 Sparrowhawk
SV F60 Biggerhawk
Tak Teeguls, SV MG, SV Stablelock tripod, TV Gibraltar tripod, a rebuilt TV Gibraltar tripod with fixed Walnut/Oak legs, M1 on Bogen475
... Naglers, Panoptics, Stratus'
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Al Canarelli
Carpal Tunnel
Reged: 12/06/07
Posts: 2611
Loc: Central New Jersey
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Quote:
Quote:
A speader is great in that it keeps the tripod from spreading out and ultimately collapsing as a result of the legs overpreading.
I'm trying to figure out how does the spreader keep the legs from spreading any further, but I'm just not seeing it. Tension on the clamping knob pushes the spreader upwards which in turn causes the legs to spread further out. This prevents the legs from closing together but it doesn't prevent them from spreading out even further. If the legs didn't have a stop at the hinge they would continue to spread beyond the spot where they contact the plate, like a ballerina doing a split.
The reason you're having this difficulty is because we need to define our terms. The spreader on a tripod is the plate, located near the top of the tripod through which a threaded rod passing through the center and containing a locking knob on bottom to increase tension. The folding arms (which limit how far the legs will open) are known as extention struts and there are three of them.
When you tighten the clamping knob under the spreader, you are forcing the legs to open, or spread, and increasing tension against the extention struts, or what ever mechanism is used to keep the legs closed. The tension created translates into unusually high rigidity and creates a very solid tripod.
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mclewis1
Thread Killer
Reged: 02/25/06
Posts: 3948
Loc: New Brunswick, Canada
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Sorry Al but in the world of surveyor tripods there is usually no center bolt and plate and a "spreader bar" is the collapsible set of arms that you've described as "extension struts".
So in order to handle the semantics we first need to know what type of tripod we're dealing with. The heavier tripods found under most gems or the surveyor style tripods.
Quote:
I want to use a surveyor tripod off Ebay with a CG-5 to surveyor tripod adapter from Universal Astronomics. None of the surveyor tripods come with spreaders. My feeling is this should be a much sturdier mount than the standard SVP tripod but should I worry about not having a spreader?
Steve, if you notice on the UA website their surveyor tripods come with spreader bars. Personally I find a surveyor style tripod is definitely more rigid with the bars than without. I originally bought a tripod without the bars because it was cheaper ... big mistake. If I could do it over today I'd defiantly spend the extra money.
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Mark
C11, C6, APM/TMB115, and AT80ED - Tandem mount CGE and CG-5A, WO EZ-Touch and AT Voyager
25x100s and 8x56s, T-Mount Light, Mark 1 eyeballs - Modded 350D, DSI-P, SPC900, Mallincam
Just because you can doesn't necessarily mean that you should
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David L
sage
Reged: 11/12/07
Posts: 278
Loc: Lee County Iowa
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Here is a spreader I recently added to a tripod. http://farm4.static.flickr.com/3614/4066562372_ff8eeec05c_s.jpg Dave
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hcsceo
member
Reged: 10/14/09
Posts: 30
Loc: Austin, TX
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OK I think I see the picture on all of this now. My plan was to get a surveror tripod like Mark and just install a spreader that screwed in to the bottom of the tripod and forced the legs out to thier stops. It seems that perhaps the best solution would be a spreader located half way between the tripod head and the location that chains might be connected near the bottom to keep the legs from going any further out. This should also give me a pretty good area for keeping EP's and other incedentals.
UA does show thier surveyor tripods with a spreader bar below but the cost seems excessive to me when a similar used surveyor tripod without spreader is a 1/4 of the price and perhaps manufacturing a spreader would be easy.
I think I'm going to find a used surveyor tripod and figure out how to make it work when it gets here. Getting the SVP attached is not going to be an issue with the adapter plate. I'll figure the legs out after the fact. After a bunch of thought I think the spreader is also an important saftey feature given the weight of everything. The next time my drunk neighbor comes over and wants to look I won't have to worry about the legs folding in when he falls into it.
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Steve
In the Texas Hill Country!
Celestron C6-N 750mm F5, Skyview Pro Mount
Proudly Classified as a NEWB
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Phil Frederick
scholastic sledgehammer
Reged: 12/19/05
Posts: 844
Loc: Seattle, WA & La Paz MX
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Well, we DO have problems with definitions, semantics and terminology! 
I've attached a pic of an Oberwerk surveyor type tripod that shows the spreader (as I called it)on the lower portion of the tripod that keeps the tripod from splaying out beyond a reasonable point. On the uppper part of the tripod is what I called the 'leg locker'--others called it a spreader--which attaches the mount (in this case a Tak Teegul) to the tripod head with a long bolt using a clamping knob from below that snugs the 'leg locker' up against the tripod legs and secures the whole assembly. Legs and leg locker (above) in compression and legs and spreader (below) in tension. You can also add a tray to the lower spreader to further improve stability if necessary.
I think we all often mean the same things but because of terminology we often create confused interpretations on the parts of our readers!
Peace all and lets just keep talking!
Phil
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Phil
Intes M500 MCT (Teton Mods)
Stellarvue SV115EDT
Stellarvue SVR70ED Raptor
Orion ST80 f/5 w/Crayford
SV F50 Sparrowhawk
SV F60 Biggerhawk
Tak Teeguls, SV MG, SV Stablelock tripod, TV Gibraltar tripod, a rebuilt TV Gibraltar tripod with fixed Walnut/Oak legs, M1 on Bogen475
... Naglers, Panoptics, Stratus'
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mclewis1
Thread Killer
Reged: 02/25/06
Posts: 3948
Loc: New Brunswick, Canada
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Quote:
My plan was to get a surveror tripod like Mark and just install a spreader that screwed in to the bottom of the tripod and forced the legs out to thier stops. It seems that perhaps the best solution would be a spreader located half way between the tripod head and the location that chains might be connected near the bottom to keep the legs from going any further out.
All the surveyor type tripods I've seen don't have any "stops" where they join the legs to the top plate so you can effectively spread any leg out as wide as you want.
Unless your load is really light I think your going to need something positive to "stop" the legs. On my surveyor I added heavier chains at the top of the legs. I am also considering adding a "spreader or leg extension" of some sort for a more positive stop about 2' down the legs.
Holding the legs from spreading too much is really necessary. Putting the legs under extra tension with the spreader or plate that pulls up against the inside of the tripod legs is also a good idea.
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Mark
C11, C6, APM/TMB115, and AT80ED - Tandem mount CGE and CG-5A, WO EZ-Touch and AT Voyager
25x100s and 8x56s, T-Mount Light, Mark 1 eyeballs - Modded 350D, DSI-P, SPC900, Mallincam
Just because you can doesn't necessarily mean that you should
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hcsceo
member
Reged: 10/14/09
Posts: 30
Loc: Austin, TX
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Phil you are my new hero. This is exactly what I'm thinking I'm going to do. I'll probably use chains for the lower section for ease of installation.
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Steve
In the Texas Hill Country!
Celestron C6-N 750mm F5, Skyview Pro Mount
Proudly Classified as a NEWB
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Phil Frederick
scholastic sledgehammer
Reged: 12/19/05
Posts: 844
Loc: Seattle, WA & La Paz MX
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Steve,
Jeez! Nobody has called me a hero in days!  Glad the pic helped.
Since you want to use chains to limit the splay of the legs I've attached another pic for you. In this case I've added chains to a TV Gibraltar tripod. In this case the chains merely act as an emergency stop when you're attaching the fixed tray to the legs with thumb screws--it's the tray that locks the legs and stabilizes the tripod while the chains end up with a little bit of sag once the tray is attached and are not in tension.
If you want to put the chains in tension to limit the splay by using the 'long bolt' type leg locker, just make sure the chains are pretty stout and that you have a very solid connection to the tripod legs to avoid any potential pull-out.
Hope this helps.
Phil
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Phil
Intes M500 MCT (Teton Mods)
Stellarvue SV115EDT
Stellarvue SVR70ED Raptor
Orion ST80 f/5 w/Crayford
SV F50 Sparrowhawk
SV F60 Biggerhawk
Tak Teeguls, SV MG, SV Stablelock tripod, TV Gibraltar tripod, a rebuilt TV Gibraltar tripod with fixed Walnut/Oak legs, M1 on Bogen475
... Naglers, Panoptics, Stratus'
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hcsceo
member
Reged: 10/14/09
Posts: 30
Loc: Austin, TX
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Yea I'm thinking about drilling a hole and using an eyebolt on each leg. I'm really hoping to find a wooden type as I won't have to worry about the hollow extruded aluminum crushing. I think I have a really good plan now that will be less expensive and stronger than the stock SVP tripod. You guys have been a big help.
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Steve
In the Texas Hill Country!
Celestron C6-N 750mm F5, Skyview Pro Mount
Proudly Classified as a NEWB
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94bamf
professor emeritus
Reged: 12/15/08
Posts: 716
Loc: Kansas City,Mo
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Quote:
Yea I'm thinking about drilling a hole and using an eyebolt on each leg. I'm really hoping to find a wooden type as I won't have to worry about the hollow extruded aluminum crushing. I think I have a really good plan now that will be less expensive and stronger than the stock SVP tripod. You guys have been a big help.
I can't comment on all the different types of surveyor tripods, but I will tell you that most, especially the type that Bigbinoculars/Oberwerk sells, is not even close to the strength or stability of the current 1.75" Skyview Pro tripod. The Skyview pro tripod will easily handle a 20 lb OTA, I would never even think of mounting a telescope that heavy on my Oberwerk surveyor tripod. Depending on how big a scope you are gonna put on your mount, you might wanna rethink using one of these.
Ken
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Telescopes:
Celestron C6 SCT on CG4 mount
Skywatcher 8 inch F/5 Newt on a GEM
Celestron 8 inch Starhopper Dob
Celestron Oynx 80ED
Celestron C130 Mak
Celestron C102HD
Binoculars:
Nikon 7x35 Action
Nikon 7x50 Action
Zen Ray Summit 10x42
Celestron 10x42 Noble
Orion 10x50 Scenix
Celestron 10x50 Noble
Pentax 12x50 PCF WP II
Celestron 15x70 Skymaster
Oberwerk 20x60
Zhumell 20x80
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Ian Robinson
Pooh-Bah
Reged: 01/29/09
Posts: 1165
Loc: Gateshead.NSW Nth Coast,Austra...
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I've been brained by my telescope when my old CG5 fell over ... didn't do the mount a lot of good .... bent the RA worm.
Had I had the spreader on , the tripod may not have fallen over (maybe).
The spreader , stiffens up the tripod assembly too , helps dampen vibrations too.
Edited by Ian Robinson (11/03/09 06:41 AM)
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hcsceo
member
Reged: 10/14/09
Posts: 30
Loc: Austin, TX
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Quote:
I can't comment on all the different types of surveyor tripods, but I will tell you that most, especially the type that Bigbinoculars/Oberwerk sells, is not even close to the strength or stability of the current 1.75" Skyview Pro tripod. The Skyview pro tripod will easily handle a 20 lb OTA, I would never even think of mounting a telescope that heavy on my Oberwerk surveyor tripod. Depending on how big a scope you are gonna put on your mount, you might wanna rethink using one of these.
My scope isn't really that heavy but I'm hoping that I can use this mount in the future for a 9.25 SCT so I'm definately thinking about the tripod now. I checked that tripod you linked to and it is about 1/2 the weight of the others that I'm looking into (Oberwerk 701 with head is 10#). The tripods I'm considering start at $250 new and can be had used for around $50 and generally weigh about 20# without mount attached. Thanks for all the info as it is really helping me out.
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Steve
In the Texas Hill Country!
Celestron C6-N 750mm F5, Skyview Pro Mount
Proudly Classified as a NEWB
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