New focuser for Meade 127

[petevasey]

Some of you may recall I put my Meade Series 5000 127 refractor up for sale a few weeks ago.  On impulse I'd bought a current model of similar size at a good price, mainly because after damaging the Meade focuser some years ago although I managed to partly repair it, it was always marginal with my heavy camera.  But unfortunately the replacement turned out to have misaligned optics, and I returned it.  And decided to bite the bullet and replace the focuser - something I'd toyed with after the original damage, but was put off by the need for a substantial adapter to fit a new focuser to the OTA.

I had in my bits and pieces bin an aluminium disc which was just large enough to make into an adapter for the focuser I'd set my sights on - this one.  Before ordering the focuser , with heart in mouth I set to with my lathe to make the OTA thread - 130M 1 mm pitch female.  (That's nominal 130 mm diameter, metric thread).  If I was successful with that, then I would order the focuser.  And that is what happened.

The focuser arrived only four days after ordering - well done Teleskop Service!  I then of course with heart even further in my mouth had to make a 90M male thread to mate with the focuser - I didn't want to do that until I had the mating part on hand to check the fit.  Fortunately that went even better than the female thread, so all fitted together nicely.  Photos below.  The new focuser is of course in the bottom picture.  I had already bought a 30mm finder  which is shown in the pic.  I didn't have a bracket for the original Meade finder - its bracket is specific to the Meade focuser.  But I think I've located one.  I might then use that on my 10" RC.  With the new focuser the scope is a pleasure to use, and a 'keeper'.  Well worth the effort!

The Meade 127 is generally well liked with good optics, so if anyone else has one and their focuser is a bit the worse for wear (they are a simple Crayford design bearing onto anodised aluminium) I can recommend replacing the focuser.  The only sticking point is the adapter.  If you don't have access to a machine shop, TS will make one.

Cheers,

Peter

 

Edited October 28, 2019 by petevasey

[johninderby]

I bought one of these focusers last week. Not bad at all for the price. Brass knobs fitted to match the scope and the chrome fine ficus knob replaced with a black one.

 

Edited October 29, 2019 by johninderby

[petevasey]

Nice job, John.

Did your scope already have the correct M90 thread at the back?  And did you make the knobs yourself?  The edge milling looks excellent!

Cheers,

Peter

[johninderby]

Used a now discontinued Baader adapter to connect to the OTA. pity they’ve stopped making it as it comes in very handy for a number of scopes. Was intending to fit this focuser to a Cassegrain scope  but the drawtube was a bit too long so this ended up on Big Red and the Badder Steeltrack originaly fitted is now on the Cassegrain.

Knobs are standard stuff bought from Amazon and eBay. Brass thunbscrews are getting harder to find now though. Just had to add nylon tips to the two large screws though. 

I built Big Red a few years ago using Carton optics.

Edited October 29, 2019 by johninderby

[petevasey]

'Big Red' looks very smart and  l  o  n  g, John.  What's the specifications?

Cheers,

Peter

[johninderby]

It’S a 100mm f/13 using Japanese Carton optics. Gives better planetary views than a FPL53 100mm triplet APO. The optics were made in the days when good achromats were finished to the highest standards. Nowadays you only see cheap achros and the manufactures don’t spend the time or money on them.
 

 

[Merlin66]

I use the same Carton 100 f13 objective on the digital spectroheliograph. Impressive performer.

 

[Fab1]

Hi Peter,

First of all, thanks a lot for sharing your experince regarding the focuser replacement! I have the same issues with the crayford focuser attached.

I also plan to replace the focuser on my old 5" Meade Series 5000. Currently it is still a thought experiment. Before going ahead, the OTA male thread on your 127 is a 130M, 1 mm pitch thread?

Thanks and best Regards

Fabian

[petevasey]

2 hours ago, Fab1 said:

Hi Peter,

First of all, thanks a lot for sharing your experince regarding the focuser replacement! I have the same issues with the crayford focuser attached.

I also plan to replace the focuser on my old 5" Meade Series 5000. Currently it is still a thought experiment. Before going ahead, the OTA male thread on your 127 is a 130M, 1 mm pitch thread?

Thanks and best Regards

Fabian

Hi, Fabian,

Yes, that's the 'nominal' thread as I measured it.  But I recommend you remove the existing focuser and check the thread diameter before commencing work.  Because I made the part myself I was able to check the fit as I went along, although it was extremely hairy - I had to remove and accurately replace the disc on my little lathe - the lathe bed got in the way of trying the tube in situ.  But all was well in the end.  Well worth the upgrade.  Just one point - the original 8x50 finder is slightly larger than the current readily available ones and doesn't fit into the usual 3-point (one point spring loaded) finder brackets.  But as you see I bought a new finder which does an excellent job.

Best of luck,

Peter.

[Fab1]

Hi Peter,

 

Many thanks for your detailed feedback! I have measured 130mm as well, pitch should be the same.

I will check as well with my local astro-stores, if they can support me further on this project with a suitable adapter. 

 

Best Regards

 

Fabian

[Fab1]

Hi Peter,

(And all others suffering with the stock crayford focuser of the Meade 127 Series 5000 APO)

Just wanted to let you know, I found another solution to replace the focuser on the telescope, no need to fully replace the M130x1 adapter from the OTA Tube. And you can keep the nice blue ring

With loosening a small setscrew on the old focuser close to the blue ring for the finder scope, the actual focuser can be removed by rotation. The male thread used on the telescope side – at least on my version – is a M70x0,75. A caliper and a screw gauge is helpful. So, what I did is to order a customized adapter to match the M68x1 of the Baader Diamond Steeltrack std dovetail adapter. And with the adapter to be approx. 2cm in length, the focus travel should be quite similar to the old focuser.

Glad this was working very well for me. It makes the 5” a very good scope again and I can now use it with autofocus for astrophotography.

Have a good day and clear skies everyone.

Fabian

 

[lakio]

On 09/08/2022 at 12:31, Fab1 said:

So, what I did is to order a customized adapter to match the M68x1 of the Baader Diamond Steeltrack std dovetail adapter.

 

Hi Fabian, your post helped me a lot. I have a question, where did you have the mentioned intermediate piece made?

Best regards

Laco

[Fab1]

Hi Laco,

 

As an example, check out the options of TS - this one might do it for you: https://www.teleskop-express.de/shop/product_info.php/info/p9286_TS-Optics-custom-made-Adapter.html

 

Allow me to emphasize to do the measuring by yourself, as there might be different versions of the series 5000.

 

Your local shop might help you, and provide options.

 

Best Regards

 

Fabian