More attempts on EQ3-2 improvement

[jacksdad]

Let's go over all this again!

 

Hopefully, one or two things might be a little different though

 

The mount itself, I just followed the usual steps of stripping the whole thing down, cleaning, new grease and carefully adjusting to get everything as smooth and stable as possible. There are a couple of very small details that might be worth mentioning later, but I'll leave that as an 'on request' for the moment.

 

By far the weakest area is the tripod. It's too lightly built, it's too flexible and with a 150PL mounted it just feels wrong.

 

From my camera days I'm bringing the thought that lack of weight and stiffness = lack of stability. I always used to tighten all joints on my photo tripods and hang stuff off the middle to make it stable, so that's the route to begin with.

 

Filling the legs with sand is quite common, so I got some play sand out of the shed and made sure it was nicely dry...

 

 

A toughspot between the window sill and dining room table seemed the ideal location to me as it was over a radiator - I shan't write what the wife thought though...

 

So, strip the 'pod and apply sealant to the leg caps

 

 

Then fill with sand.

 

But not just that, I put a length of 1/2" galv steel pipe inside too

 

 

 

These central leg sections weighed 600g as stock, now they're a bit more portly

 

 

I did pretty much the same with the outer sections too, which seems less common. The lower ends don't have caps though so the last inch or so needs flooding with sealant to hold the sand in, as do all the screw holes on every leg.

 

In total, this added almost 6kg to the overall weight of the 'pod and whereas I could deform the legs with my fingers before, now I can't.

 

More soon...

[michael.h.f.wilkinson]

Interesting approach. I sometimes consider doing the same makeover on my EQ3-2 tripod using hardwood like I did with an old EQ1/EQ2 tripod

Works a treat, and I now use it combined with my mini-giro mount

[jacksdad]

Wooden one looks nice.

 

My concern would be stability with my son's ota mounted - I'd want something like an eyebolt up at the top so I could tie it to the ground and make falling over an impossibility.

 

With a lighter (and shorter) tube the natural damping ability of wood would help a lot though.

 

With 'mine', what I've done so far has reduced the shakes (looking through the ep, knocking the tube etc.) from almost 10 seconds to about 1 1/2, but it has highlighted other areas that need a coat of looking at.

[John]

The best improvement for an EQ3-2 is to put it on an HEQ5 or CG5 steel tubed tripod. The latter has 2" steel tubed legs. Both make a big difference to mount stability especially with long tubes on board.

[jacksdad]

So, those areas...

 

Firstly, the spreader is attached with these tiny self tapping screws (well, they were, I replaced them with small machine screws)

 

 

But that's still not good. I'm intending to put through bolts in instead so they definitely can't pull out and make the 'pod do the splits.

 

The other part is where the legs join the top.

 

 

These rely on the fit of the pivot bolt for location - if you tug on the counterweight bar lightly there is discernable play here - overtightening the bolts won't do any good... I may well ream those holes and sleeve them to remove the play. A more remote possibility is using one of the plastic lugs as a pattern to cast some aluminium ones which will remove some more flex - I'll probably see if that's warranted after sleeving...

[jacksdad]

12 minutes ago, John said:

The best improvement for an EQ3-2 is to put it on an HEQ5 or CG5 steel tubed tripod. The latter has 2" steel tubed legs. Both make a big difference to mount stability especially with long tubes on board.

Seems a bit 'financial' for my liking 

 

Steel legs are a future option though, I have a variety of interesting lumps of metal sat about so you never know

[John]

4 minutes ago, jacksdad said:

Seems a bit 'financial' for my liking 

 

Steel legs are a future option though, I have a variety of interesting lumps of metal sat about so you never know

With a 6" F/8 scope the benefits are really substantial when a little magnification is used so the £'s spent fade away very quickly. Even with the steel legs I feel the EQ3-2 is borderline with such a scope on board but there you go - they sell the darn thing that way

 

[mikeDnight]

A Hargreaves Strut may work well, adding to the rigidity of the set-up.  Mostly used with long refractors, there is no reason why the HS wouldn't work with a Newtonian.

Mike

[jacksdad]

Please read the following in the spirit it's intended, I'm in no way saying any one way is right or wrong, they're just different.

 

In most hobbies, broadly speaking, the majority of people tend toward one of two camps. There are those who buy solutions, and there are those that make their own solutions. Obviously it's rare that anyone is completely one way or the other, but the tendency is there nonetheless.

 

Take me (and my son) for instance - he (we) bought the 'scope - we could've gone down the beach, collected sand, smelted some glass, ground a mirror blank, coated it, rolled a tube (you get the idea) but instead a complete solution was purchased.

 

When it comes to making improvements, yes we could go shopping, but making the solutions not only saves money for other things it also helps develop his skills - there are times that something needs fixing and you simply can't call on someone else.

 

Now:

 

2 hours ago, John said:

With a 6" F/8 scope the benefits are really substantial when a little magnification is used so the £'s spent fade away very quickly. Even with the steel legs I feel the EQ3-2 is borderline with such a scope on board but there you go - they sell the darn thing that way

 

 

I actually agree (except for the spending £ part - if you don't have them it's not an option anyway). If you're a "buy solution" person then buying this particular solution will leave you wanting. As standard, calling the mount and tripod borderline for the tube might actually be a bit generous.

 

Thing is, if you have the money and desire to buy solutions and simply want to sit at the ep then more power to you - but the one thing I wholeheartedly disagree with is telling someone they're wrong to want to go a different route. I know I'm perfectly capable of making parts - casting aluminium, machining the blanks to tighter tolerances than mass production allows, that sort of thing - so the advice to "buy something else" kinda gets my goat a bit.

[jacksdad]

3 hours ago, mikeDnight said:

A Hargreaves Strut may work well, adding to the rigidity of the set-up.  Mostly used with long refractors, there is no reason why the HS wouldn't work with a Newtonian.

Mike

 

I had no idea it had a name 

 

It's a good idea though, and one that deserves investigation and an experiment I think.

[John]

4 hours ago, jacksdad said:

Please read the following in the spirit it's intended, I'm in no way saying any one way is right or wrong, they're just different.

 

In most hobbies, broadly speaking, the majority of people tend toward one of two camps. There are those who buy solutions, and there are those that make their own solutions. Obviously it's rare that anyone is completely one way or the other, but the tendency is there nonetheless.

 

Take me (and my son) for instance - he (we) bought the 'scope - we could've gone down the beach, collected sand, smelted some glass, ground a mirror blank, coated it, rolled a tube (you get the idea) but instead a complete solution was purchased.

 

When it comes to making improvements, yes we could go shopping, but making the solutions not only saves money for other things it also helps develop his skills - there are times that something needs fixing and you simply can't call on someone else.

 

Now:

 

 

I actually agree (except for the spending £ part - if you don't have them it's not an option anyway). If you're a "buy solution" person then buying this particular solution will leave you wanting. As standard, calling the mount and tripod borderline for the tube might actually be a bit generous.

 

Thing is, if you have the money and desire to buy solutions and simply want to sit at the ep then more power to you - but the one thing I wholeheartedly disagree with is telling someone they're wrong to want to go a different route. I know I'm perfectly capable of making parts - casting aluminium, machining the blanks to tighter tolerances than mass production allows, that sort of thing - so the advice to "buy something else" kinda gets my goat a bit.

Sorry to get your goat. I was just trying to give advice based on my experience of this mount.

With your skills and resources (which I had no prior knowledge of, not knowing you) you should have no problem in making a heavier duty tripod for the EQ3-2 which would be a big improvement on the aluminum one and at very low, or even no, cost 

 

[bobro]

Great to see the work going into making the EQ3 tripod more stable. Of course, perhaps the main way to show the result is to make a before/after comparison. I've been occupied with imaging using a 130mm reflector scope on a Meade EQ2 mount. This has tubular steel legs - an improvement on an EQ3? So far guiding has kept me occupied enough not to fill the legs with sand, but overall stability has an obvious effect on guiding, but not too much on imaging as my scope has a relatively short focal length of 650mm. I've tried putting weight on the tripod shelf - no obvious effect. Still wondering about sand in the legs - would be useful to see how much an EQ3 tripod can be improved as a reference. Keep up the good work!

[jacksdad]

1 hour ago, John said:

Sorry to get your goat. I was just trying to give advice based on my experiece of this mount.

With your skills and resources (which I had no prior knowledge of, not knowing you) you should have no problem in making a heavier duty tripod for the EQ3-2 which would be a big improvement on the aluminum one and at very low, or even no, cost 

 

Yeah, maybe I ranted a bit about it I just see a lot of instances where people suggest trying something and are told it's not worthwhile, better to buy something - sometimes it's better, often it's just easier and quicker instead.

[jacksdad]

1 hour ago, bobro said:

Great to see the work going into making the EQ3 tripod more stable. Of course, perhaps the main way to show the result is to make a before/after comparison. I've been occupied with imaging using a 130mm reflector scope on a Meade EQ2 mount. This has tubular steel legs - an improvement on an EQ3? So far guiding has kept me occupied enough not to fill the legs with sand, but overall stability has an obvious effect on guiding, but not too much on imaging as my scope has a relatively short focal length of 650mm. I've tried putting weight on the tripod shelf - no obvious effect. Still wondering about sand in the legs - would be useful to see how much an EQ3 tripod can be improved as a reference. Keep up the good work!

 

I can't do much of a before/after I'm afraid, having not done much before...

 

The only form of before evidence I have is an image I took through a double glazed window in the daytime, which showed two things:

 

As the shutter was fired by remote, the inertia of the mirror flipping on the dslr was enough to blur the image slightly, and

 

The sensor on my camera is in dire need of cleaning 

 

I'll upload it in a bit - I don't have it stored on my phone...

[jacksdad]

Ok, so, an almost useless example...

 

Image taken with a Pentax K100D (with a very dirty sensor), fired with an IR remote unit (so no shakes induced by touch), though a double glazed window with only the small cap removed from the 'scope (see, I said useless)

 

 

In all honesty I only took the picture to see if it was possible to achieve focus with a directly mounted dslr (I've seen many references to this not being possible on this 'scope without moving mirrors and such) so I did nothing at all with respect to setting up - that hedge is a good 1/2 mile+ away so I think I achieved the actual aim of the pic.

[jacksdad]

Delays! (See focuser thread...)

 

After more thought, a strut may (/will definitely) help, as would sleeving the pivots, but I think the biggest change would come from removing the need to have hand contact with the scope or the mount.

 

Watch this space

[jacksdad]

Well, I did some more fiddling and reached a conclusion of sorts.

 

Fundamentally this mount isn't bad.

 

Unfortunately, I'm thinking that the scope is too long...

 

There's still vibration and settling issues, and while it stabilises quite quickly (compared to how it was) it's still a pain. Once focussed it's not bad, but manually tracking stuff makes the image dance about.

 

I've now tried it with a skymax 102 (which a friend donated to me the other day) mounted instead of the 150pl and it's absolutely fine.

 

Now, the 150 is (imho) well within the static weight capability of the mount, but the leverage imposed due to having the mirror/eyepiece so far away from the centre of gravity means the mount doesn't stand much chance really - try holding a bag of sugar in your hand, easy right? Now put it on a 2ft stick and hold it steady at arm's length

 

I'm not giving up on it totally though, once we have a scope house built with a permanent pier I think it'll do much better.

[Dr_Ju_ju]

I have a couple of the cheeper EQ3 tripods & instead of filling with sand, I filled each of the legstruts with small rock concrete. Makes them 3 times heavier & much more stable...