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Modify and strengthen tripod


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I have a classic 1970s long tube refractor that didn't come with a mount or tripod. I do own an aluminium manfrotto O55c camera tripod fitted with a R141 pan and tilt head.

This is a substantial tripod for small cameras but I hadn't quite appreciated how much stress a long tube scope puts on the tripod. If I can avoid it, I want to spend no money on this hobby (!).  I've tested the weak points of the tripod as best I can and they seem to be the centre column fixing (a spring clamp that is applied to one side of the tube only) and the lower skinny section of the legs.

- The plan is to remove the centre column entirely.  I'll fix the head directly to the legs using a length of threaded rod passing through the hole in the casting at the top of the legs and bolted in place underneath using a large washer and nut.

- the legs start off as 30mm diameter aluminium tube but by the feet sections are only 20mm.

- The telescopic sections are clamped with spring loaded alloy "flip lock" clamps.  There was definite flex at the clamp positions and while attempting to tighten the nuts on the lower clamps, I managed to break two of them - so I'm now left with a tall one legged tripod or a shorter, sturdier 3 legged tripod!

I'm pondering what can be done about the legs now.

- I could leave it as a short two section tripod and try and raise the height by adding some wide steel tubing between the head and the leg casting

- I could replace the legs in their entirety leaving me with just the casting to which I fit replacement one piece steel tubes

What do you think?

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I have a classic 1970s long tube refractor that didn't come with a mount or tripod. I do own an aluminium manfrotto O55c camera tripod fitted with a R141 pan and tilt head.

This is a substantial tripod for small cameras but I hadn't quite appreciated how much stress a long tube scope puts on the tripod. If I can avoid it, I want to spend no money on this hobby (!).  I've tested the weak points of the tripod as best I can and they seem to be the centre column fixing (a spring clamp that is applied to one side of the tube only) and the lower skinny section of the legs.

- The plan is to remove the centre column entirely.  I'll fix the head directly to the legs using a length of threaded rod passing through the hole in the casting at the top of the legs and bolted in place underneath using a large washer and nut.

- the legs start off as 30mm diameter aluminium tube but by the feet sections are only 20mm.

- The telescopic sections are clamped with spring loaded alloy "flip lock" clamps.  There was definite flex at the clamp positions and while attempting to tighten the nuts on the lower clamps, I managed to break two of them - so I'm now left with a tall one legged tripod or a shorter, sturdier 3 legged tripod!

I'm pondering what can be done about the legs now.

- I could leave it as a short two section tripod and try and raise the height by adding some wide steel tubing between the head and the leg casting

- I could replace the legs in their entirety leaving me with just the casting to which I fit replacement one piece steel tubes

What do you think?

As I was reading your post this is the solution that came to mind. In my experience (limited) extending tripod legs leads to wobble. 

I will be interested to hear others' thoughts.

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As I was reading your post this is the solution that came to mind. In my experience (limited) extending tripod legs leads to wobble. 

I will be interested to hear others' thoughts.

Just thought of another solution: mount the two section tripod on some kind of platform or fashion some kind of tall "feet" (like fence post supports?) the tripod can rest on...

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Just thought of another solution: mount the two section tripod on some kind of platform or fashion some kind of tall "feet" (like fence post supports?) the tripod can rest on...

That would work so long as it wasn't a tripping hazard in the dark. I can see it would be all to easy to give them a slight nudge and the whole thing come crashing down but then I'm clumsy.

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I have a different model of manfrotto tripod but some things I have found with mine that may help;

The centre column is required to be slightly extended otherwise the control lever will clash with the tripod at fairly low elevations, removing the centre column may make it impossible to point the scope up.

The lowest section of the legs I normally leave retracted.

I used some 2B pencil on the ball to make it smoother as it was too jerky.

By far the best way of operating I found was to turn the head 90° on its side, this provides a pivot point that can be balanced, operating the head like you would with a camera is very difficult as changing the elevation shifts the balance one way or the other.

/Dan

Sent from my iPad using Tapatalk

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What aperture and focal length and weight is the scope?  It seems to me that when all is done it will still be pairing a scope with something that was made for a camera. Compact wide field scopes can work on a photo tripod but longer OTAs will tend to wobble, I think. Although it means forking out on  a new mount, (or second hand?) why not mount it on something like a SW AZ4?

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Personally I would probably accept the need for some cost in order to get the scope mounted properly. Astroboot often have tripod legs available, there are three ali ones on there currently for £15 for example which may or may not be suitable with some mods.

My suggestion however would be to pick up an old EQ6 tripod, often around £50 or £60. These have 2" Stainless Steel legs and are rock solid. I use one with a Giro style head and as you suggested I have made a 30cm pier extension for it from a section of thick walled aluminium tube cut to length, pimped with CF wrap in the last image. I'm sure you could fit your pan and tilt head to this as a starter. With the Giro it easily handles a 120ED and an 8" SCT.

b15eb30f7ca55f7407451536fd00fa1e.jpg

65f5f31abaaf73cfc2af308fd48b46c5.jpg

08b600c9535f3da07a632e0b2c9545c8.jpg

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What material is the tripod head made of? Could you make some nice wooded legs that would befit your 70's scope?

The head is a manfrotto 141RC - it is a reasonably hefty 3 way pan and tilt with substantial locking knobs. I couldn't say what it was made of but a variety of metals would be my guess. I don't think the head is the weakest point, the centre column is. It's thin walled aluminium and it's telescopic - there's another tube inside the main tube. It makes sense to me to do away with the column and bolt the head directly to the casting.  I don't think it would be easy to fit wooden legs because it doesn't have the fork and bolt arrangement of astro tripods. Instead there are short metal "cups" or sockets fitted to the casting using a clamp arrangement. Metal tubes them slide into these cups/spockets and are secured by clamping.  Replacing the aluminium tubes with single piece steel would seem the most likely option but maybe expensive.

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I have a different model of manfrotto tripod but some things I have found with mine that may help;

The centre column is required to be slightly extended otherwise the control lever will clash with the tripod at fairly low elevations, removing the centre column may make it impossible to point the scope up.

The lowest section of the legs I normally leave retracted.

I used some 2B pencil on the ball to make it smoother as it was too jerky.

By far the best way of operating I found was to turn the head 90° on its side, this provides a pivot point that can be balanced, operating the head like you would with a camera is very difficult as changing the elevation shifts the balance one way or the other.

/Dan

Sent from my iPad using Tapatalk

I tried mine with a ball head and found also that it worked best on it's side. But my pan and tilt is more solid and easier to point and clamp accurately so I've switched to that.

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What aperture and focal length and weight is the scope?  It seems to me that when all is done it will still be pairing a scope with something that was made for a camera. Compact wide field scopes can work on a photo tripod but longer OTAs will tend to wobble, I think. Although it means forking out on  a new mount, (or second hand?) why not mount it on something like a SW AZ4?

Hi

It's a 3" 1250mm FL long-tube metal OTA refractor. The OTA weighs about 3.2Kg without accessories.

I agree that a skytee or an Az4 would be more appropriate but they are lots of money. The scope cost me £27.   I had initally hoped that it would be the bargain of all time and I would not need to spend any additional money. I was disappointed (naive?) in that hope in that I so far I've bought tube rings, a dovetail, a new visual back, new diagonal, three new eyepieces, a t mount adaptor, a moon filter, a bahtinov mask, vixen finder bracket and a red dot/reticule finder (and wasted another £20 on a 0.965 - 1.25" adaptor that serves no purpose).

I've only managed to look at the moon a couple of times so far and I want to stop spending now before my £27 bargain costs me £1000!post-47707-0-04540500-1448796530_thumb.j

Sorry about the poor cameraphone snap.

edit: The circle dangling from the mounting bar is the lid from a tin of finnish licorice I'm using as a lens cap. I like it ;-)

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Personally I would probably accept the need for some cost in order to get the scope mounted properly. Astroboot often have tripod legs available, there are three ali ones on there currently for £15 for example which may or may not be suitable with some mods.

My suggestion however would be to pick up an old EQ6 tripod, often around £50 or £60. These have 2" Stainless Steel legs and are rock solid. I use one with a Giro style head and as you suggested I have made a 30cm pier extension for it from a section of thick walled aluminium tube cut to length, pimped with CF wrap in the last image. I'm sure you could fit your pan and tilt head to this as a starter. With the Giro it easily handles a 120ED and an 8" SCT.

b15eb30f7ca55f7407451536fd00fa1e.jpg

65f5f31abaaf73cfc2af308fd48b46c5.jpg

08b600c9535f3da07a632e0b2c9545c8.jpg

That looks pretty much what I was thinking of. Nice set up!

I think i'll try a similar arrangement with my tripod first.  I have this table leg from Ikea that is basically a steel tube about the right diameter to fit the legs casting and the head baseplate. I just need to cut it to the right length and pass a threaded bolt through it.  The question is, how long dare I make the tube without compromising stability?

If the tripod isn't hefty enough after all that, I think finding the EQ6 would be a plan - where would I get one from though?

Thanks very much for the suggestions - in line with what I was thinking

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Sympathise with escalating costs, one thing does tend to lead to another, however its a shame to have a nice scope that promises good views, taking so long to settle down it spoils the enjoyment. Second hand bargains are out there. Very recently there was an AZ4 on Astrobuysell for £70. Needless to say it disappeared quickly. I think it was the ally legged version but that's not so bad. There's a steel legged Meade tripod going for £80 at moment, even an EQ3 for £60 if you fancied going down the EQ path.

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That looks pretty much what I was thinking of. Nice set up!

I think i'll try a similar arrangement with my tripod first. I have this table leg from Ikea that is basically a steel tube about the right diameter to fit the legs casting and the head baseplate. I just need to cut it to the right length and pass a threaded bolt through it. The question is, how long dare I make the tube without compromising stability?

If the tripod isn't hefty enough after all that, I think finding the EQ6 would be a plan - where would I get one from though?

Thanks very much for the suggestions - in line with what I was thinking

Keep an eye on AstroBuySell for and EQ6 or CG5 tripod, basically you want one with 2" Stainless Steel legs, not aluminium.

There is a brand new one on there currently but I've picked them up for less in the past, albeit in good used condition

http://www.astrobuysell.com/uk/propview.php?view=101821

In terms of the length of extension, to a degree it depends on the thickness of tube wall. I used some which has probably 5mm thick walls and is around 70mm diameter. I ensured the faces were cut and finished flat and level and once it is tightened in place with the threaded rod it does not budge at all, it is as stable as the tripod on its own and it is 30cm long. Using the leg spreader makes a difference too, so perhaps try making one for your tripod if you don't go for an alternative.

Good luck [emoji3][emoji106]

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Keep an eye on AstroBuySell for and EQ6 or CG5 tripod, basically you want one with 2" Stainless Steel legs, not aluminium.

There is a brand new one on there currently but I've picked them up for less in the past, albeit in good used condition

http://www.astrobuysell.com/uk/propview.php?view=101821

In terms of the length of extension, to a degree it depends on the thickness of tube wall. I used some which has probably 5mm thick walls and is around 70mm diameter. I ensured the faces were cut and finished flat and level and once it is tightened in place with the threaded rod it does not budge at all, it is as stable as the tripod on its own and it is 30cm long. Using the leg spreader makes a difference too, so perhaps try making one for your tripod if you don't go for an alternative.

Good luck [emoji3][emoji106]

A quick look on ebay and I can get a 60mm diameter 3mm thick wall stainless steel 30cm tube for £11.00 incl postage. 60mm is the limit for my tripod.  I'll try it first without the tube and if dispensing with the centre column improves things, I'll give this a go.

Cheers

Dave

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A quick look on ebay and I can get a 60mm diameter 3mm thick wall stainless steel 30cm tube for £11.00 incl postage. 60mm is the limit for my tripod.  I'll try it first without the tube and if dispensing with the centre column improves things, I'll give this a go.

Cheers

Dave

The threaded rod, nuts and washers have arrived. The centre column is safely dispensed with and the head is bolted directly to the tripod legs. 

First impressions are that it has made a difference. The telescope rings, arca-swiss mounting plate and quick release plate-to-head connections seem solid. The head-to-legs connection is now very solid without any detectable wobble.  The only obvious source of flex is now the legs themselves. 30mm tubes are reasonably hunky for a portable field camera tripod but distinctly anorexic by the standards of astronomical tripods; can't do anything about that without investing in a 'proper' tripod.

Anyway for now, I shall play around with it as it is while I await the arrival of the longer threaded rod and the steel pipe.

Even if I have to go for the astro legs in the end, I'll still have got myself a pretty solid camera tripod....

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  • 2 weeks later...

The threaded rod, nuts and washers have arrived. The centre column is safely dispensed with and the head is bolted directly to the tripod legs. 

First impressions are that it has made a difference. The telescope rings, arca-swiss mounting plate and quick release plate-to-head connections seem solid. The head-to-legs connection is now very solid without any detectable wobble.  The only obvious source of flex is now the legs themselves. 30mm tubes are reasonably hunky for a portable field camera tripod but distinctly anorexic by the standards of astronomical tripods; can't do anything about that without investing in a 'proper' tripod.

Anyway for now, I shall play around with it as it is while I await the arrival of the longer threaded rod and the steel pipe.

Even if I have to go for the astro legs in the end, I'll still have got myself a pretty solid camera tripod....

Tripod is now extended with a foot long steel tube. It's seems very solid and a lot taller.  £6 for the steel tubing and a few quid for the extra long threaded rod. Not bad. 

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Looks great!!

Saves having to lay on the ground!

Now I need to get some of that flocking stuff from Wilkinsons. And maybe think about tarting up the steel tube a bit. One thing other thing I need to sort out it the lens cell. It rotates in the tube if you apply pressure (it's not actually the lens cell, it's the black bit that the lens cell screws into).

Doesn't seem to do any harm but I've taped it down for now. Need a permanent solution. There does seem to a screw or anything to tighten - maybe a line of silicon sealant would lock it?

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 One thing other thing I need to sort out it the lens cell. It rotates in the tube if you apply pressure (it's not actually the lens cell, it's the black bit that the lens cell screws into).

Doesn't seem to do any harm but I've taped it down for now. Need a permanent solution. There does seem to a screw or anything to tighten - maybe a line of silicon sealant would lock it?

Dave,

The tripod looks good! A lick of paint would finish it off nicely. Re 'the black bit that the lens cell screws into', if I recall correctly (haven't seen my scope for two months now - it's ok, I haven't seen the night sky for two months either! ;)) these screw into each other. Don't overtighten if this is the case as you'll pinch the optics. There may be a spacer in between though.

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Dave,

The tripod looks good! A lick of paint would finish it off nicely. Re 'the black bit that the lens cell screws into', if I recall correctly (haven't seen my scope for two months now - it's ok, I haven't seen the night sky for two months either! ;)) these screw into each other. Don't overtighten if this is the case as you'll pinch the optics. There may be a spacer in between though.

Hi Roy

The objective is fitted into a short barrel that screws into a flange that is attached to the main tube. The attachment between the flange and the main tube is loose such that you can rotate the whole object lens unit on the tube. I can't see any obvious fixing and the movement is rough and scraping which makes me think it is probably just and interference fit.  It won't fall off or anything, just moves a bit if you twist it. Tape has secured it just fine but isn't very neat.

What's happened to your telescope, have you sent it somewhere to be professionally upgraded?

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