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Smithysteve

Dob Renovation...

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Daz Type-R

Nice one, I'd love a bigger scope, just can't justify the spend at the moment.  Looking forward to seeing the end result.

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BAZ

That's a good bit of work to do, but it will be well worth it in the end and with Hi-Lux coatings it will produce superb views.

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Doc

Agreed the hilux coating will be a fantastic addition. The next big difference is flocking, I was sceptical when I had mine done but the difference it made was noticible. Don't forget a counterweight system as well. The 28mm UWAN I sold you was the main eyepiece I used when I had my Lightbridge, you will need to design a counterweight system or you won't be able to use it.

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Bottletopburly

Looking awesome steve ,nice project ,what are you sealing the wood with ,pre cat laquer is good comes in various finishes gloss ,satin etc you can get it in an aerosol gives a professional finish ,wear a mask though and in a ventilated area quite smelly dries quick though.

Edited by Bottletopburly

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Brantuk

Very nice job so far - I'll continue watching this thread with great interest. Nice one Steve!

 

Any help you need with sourcing a center bolt, formica, ptfe bearings, etc.... just drop me a pm. :)

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Smithysteve
1 hour ago, Doc said:

Agreed the hilux coating will be a fantastic addition. The next big difference is flocking, I was sceptical when I had mine done but the difference it made was noticible. Don't forget a counterweight system as well. The 28mm UWAN I sold you was the main eyepiece I used when I had my Lightbridge, you will need to design a counterweight system or you won't be able to use it.

Thanks Mick, looking forward to getting the flocking done, and seeing how the Optics turn out... before I stripped the scope down I tried out the big Uwan, the scope sank down under the weight, despite the scope having three sets of 5 x 100gram weights arranged around the the base of the scope! The braking system works but does not allow the scope to settle properly. So yes, good point, I need to be able to balance the scope, I will have a think about this...

1 hour ago, Bottletopburly said:

Looking awesome steve ,nice project ,what are you sealing the wood with ,pre cat laquer is good comes in various finishes gloss ,satin etc you can get it in an aerosol gives a professional finish ,wear a mask though and in a ventilated area quite smelly dries quick though.

Not heard of that stuff David, will look into it cheers!

 

25 minutes ago, Brantuk said:

Very nice job so far - I'll continue watching this thread with great interest. Nice one Steve!

 

Any help you need with sourcing a center bolt, formica, ptfe bearings, etc.... just drop me a pm. :)

Will do Kim, thanks a lot... ?

 

2 hours ago, Daz Type-R said:

Nice one, I'd love a bigger scope, just can't justify the spend at the moment.  Looking forward to seeing the end result.

Never say never! Never thought I would, but hey ho! ☺️

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Tweedledee

That is an absolutely brilliant project Steve.

 

I can see you have already spent a lot of time and effort, but it will be well worth it in the end and an improvement on the original Lightbridge. :respect:

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Smithysteve
7 minutes ago, Tweedledee said:

That is an absolutely brilliant project Steve.

 

I can see you have already spent a lot of time and effort, but it will be well worth it in the end and an improvement on the original Lightbridge. :respect:

Thanks Pete, it is a great project, actually it’s more like 3 projects in one with the optical tubes, rocker box and trolley work, plus other stuff like  setting circles etc... they are all different but necessary and it will come together, hopefully over next couple of weeks... it’s got me thinking, and keeping me busy! ?

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Bino-viewer

Great work so far Steve : i will follow your progress with interest.

 

I recently moved from a 10" dob to a 12" and was surprised at just how much bigger the 12 was.

Much heavier and i'm at the limit now i think with aperture in a solid tube.

I have the opposite issue with all the weight being at the primary end (this is in total contrast with my old 10",

where i had to use a weight belt with 1.5kg on it to get balance)

I don't need it with the 12, even with a 2+ kg load on the focuser.

 

Good luck with the 'renovation'. I'm sure it will be an amazing scope when its finished. :thumbsup:

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Smithysteve

Thanks Rob, interesting about the balance... first time I saw the veil, M32 and M110 was through a 12” I was amazed! I cannot imagine the amount of space a 16” solid tube would take up! You would need a barn! ??

 

i have done a bit more today...

The optical tubes are back from the powder coaters... they look good as new ?

I have removed the old internal masking and sealed holes and masked the external sides ready for internal priming and black finish...

 

IMG_1468%20(1).JPG?raw=1

 

 

Ready to paint now! But it will not be today...

 

IMG_1469.JPG?raw=1

 

 

Also had my 50cm diameter setting circle printed off, (a mate printed it off at work, so it was only fair I gave him a nice bottle of red wine for his troubles...???)

 

IMG_1455%20(1).JPG?raw=1

 

 

The resolution is not great, but it is certainly good enough! I am taking the circle to Ryman’s in Sutton-in-Ashfield, cost of laminating same £12.50.

 

Just making sure it fits in the base...

 

IMG_1466.JPG?raw=1

 

Thanks for looking! ?

 

 

 

Edited by Smithysteve

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Tweedledee

Looking great Steve. :thumbsup:

 

I think the 1 degree resolution on the circle is perfect. In the dark you don't want too many graduations to get confused with. If it is set up accurately your eye will interpolate much more accurately within the degree mark and your bigger eps will still show a good 1 degree FOV.

 

I'd be interested to know who did your powder coating. 

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Doc

Why are you putting the degree circle inside the base, shouldn't it go between the base and ground board unless you are cutting a viewing hole in the base board. Looking good though Steve.

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Smithysteve
1 hour ago, Tweedledee said:

I'd be interested to know who did your powder coating. 

Hi Pete, the powder coaters are just a mile or two from you...

W. H. Paint Finishers at:

Bleak Hill Siddings, Off Sheepbridge Lane, Mansfield NG18 5EW, tel. 01623 420393

Basically, they are on Sheepbridge lane, just after the traffic lights, on the left. Where the scrap yard used to be...

Ask for Zak. Minimum order is £40.00, I got both my tubes done for £40. I think that is a bargain! No orange peel finish, looks like new!

cheers!

 

Edited by Smithysteve

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Smithysteve
15 minutes ago, Doc said:

Why are you putting the degree circle inside the base, shouldn't it go between the base and ground board unless you are cutting a viewing hole in the base board. Looking good though Steve.

Hi Mick, the 50cm circle is big enough to just go in the rocker box, I will have viewing windows in the sides. I will have a fixed pointer in the rocker box. I am mounting ithe circle between two thrust bearings above the original thrust bearing and Tensioner nut, a further nut will adjust tension on the circle.  I have tried it out in a jig and works great! If I had it between the ground board and base board I would not be able to travel the scope down the side of my house... it would be too wide... that’s my plan anyway, ☺️

Edited by Smithysteve

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Smithysteve

Me too, time will tell Mick, if it does not work then it’s back to tried and tested plan B, one thing I know for sure, I have tried the Wixey and setting circles on others scopes and it really works so well, so I definitely will end up with a system of one type or another...

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Tweedledee
On 06/11/2017 at 19:09, Smithysteve said:

Hi Pete, the powder coaters are just a mile or two from you...

W. H. Paint Finishers at:

Bleak Hill Siddings, Off Sheepbridge Lane, Mansfield NG18 5EW, tel. 01623 420393

Basically, they are on Sheepbridge lane, just after the traffic lights, on the left. Where the scrap yard used to be...

Ask for Zak. Minimum order is £40.00, I got both my tubes done for £40. I think that is a bargain! No orange peel finish, looks like new!

cheers!

 

That's the company I have used several times over the past few years for blast cleaning and powder coating. Always been very satisfied with the results.

 

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Smithysteve

A bit more done...

I have dropped off my setting circle at Ryman’s, same should be back by the end of next week ?

 

Yesterday, I went to pick up my mirrors from Orion Optics, Stoke-on-Trent, this was all very exciting, and worth the 3 hour round trip. I am not a fan of most distribution/delivery systems, My old firm worked at many of these centres and I could not trust them with delivery of these precious items ???

 

The secondary has turned out like new and the primary mirror looks fantastic and almost new, just a couple of tiny marks left on same due to the level of degradation of the coatings prior to the new Hi-lux coatings. 

I spoke to the manager John, at the workshops at Orion Optics, about this, he stated the mirror is fine, the marks are negligible, with reflectivity now nearing 97%. I am totally happy with the results!?

Here is some info from the website...

What actually is Hilux ? It is a method of allowing considerably more of the light which your telescope collects being passed to your eye or camera. Typically a standard coated telescope mirror with a typical protective layer of Silicon Oxide will reflect around 87-89%. This does vary depending on the actual measurements carried out during coating, assuming the deposition is being monitored and not just literally guessed at. Hilux has a completely different set of numbers. Over a wide section of the visible spectrum, the light which your eye is most sensitive to and, the light which CCD cameras like, every surface to which Hilux is applied, reflects up to 97% of the light it receives. You can see a representative graph and more info here...

http://www.orionoptics.co.uk/OPTICS/opticalcoatingsh.html

Ok! Here is the secondary before and after...

IMG_1502.JPG?raw=1

 

IMG_1519.JPG?raw=1

 

 

The primary;

File%2009-11-2017,%2017%2037%2013.jpeg?r

 

 

IMG_1515%20(1).JPG?raw=1

the flowers are a reflection! ☺️?

 

The weather today was comparatively warm and dry, so painted the internals on the optical tubes (and me!) with 2 coats of primer and 3 coats of black paint, same is now ready to be flocked!

 

IMG_1509.JPG?raw=1

 

 

also stripped, sanded and painted the spider vanes etc.

 

IMG_1397.JPG?raw=1

 

Now...

IMG_1506.JPG?raw=1

 

Forward and on!!!

Thanks for looking...??

 

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Smithysteve
25 minutes ago, Doc said:

Looking good Steve, that mirror should be spot on now, should give you wonderful bright views.

I hope so Mick. Looking forward to first light and comparing views with the Meade LX200 etc. Still lots to do, but enjoying the whole project! ?

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Smithysteve

A quick update!

It’s been another busy week...

Cracked on with flocking the optical tubes and inside the 2” focuser.

Started with the easiest end first - the smallest... I followed the EMS posts from a couple of years ago and used an aerosol can to smooth the flock in place, starting from the seams...

Then the edges were trimmed and the holes were cut out using a Stanley knife.

What a difference! 

File%2020-11-2017,%2016%2044%2020.jpeg?r

 

 

File%2020-11-2017,%2016%2046%2022.jpeg?r

 

 

Then built everything back together...

File%2020-11-2017,%2016%2048%2032.jpeg?r

 

 

 

Mirrors went in last, and now it’s collimated ready to try! I need to do a star test at some point!

 

I have now fetched the azimuth circle from the laminators 

Here it is just perched in the old rocker box...

File%2020-11-2017,%2016%2045%2054.jpeg?r

 

And a view from the side... this will be slightly different on my new box...

File%2020-11-2017,%2016%2044%2051.jpeg?r

 

 

 

I really need a trolley to move this scope around, so I have spent several hours (actually more like 20hrs), designing a trolley that will be;

As stable as possible.

Able to travel over grass, fields, (and down the side of my house, which is only 80cm wide in parts).

I wanted large pneumatic tyres to cushion the optics and make steering easier.

Keep it as compact as possible, 

Able to ‘raise or lower’ the bed, to keep the scope as low as possible to the ground.

Incorporate ‘fast’ levelling feet

Have removable wheels.

 

I have picked up lots of pieces of advice from several mechanical people, all of them friends and keen to help. My (our!) latest design, (wheels 9), allows for easy changes to be made over the next couple of weeks to help develop the design into a workable piece of kit.

 

I have been to a local supplier and ordered the steel, mostly 25mm x 25mm box and 30mm x 30mm box section, mild steel. Also ordered the 4 x 10” rubber pneumatic castor wheels. (2 swivel, 2 fixed), should have this lot within a few days! 

Here is a simplified diagram showing basic layouts.

Top elevation

File%2020-11-2017,%2016%2030%2024.jpeg?r

 

Side elevation...

File%2020-11-2017,%2016%2030%2005.jpeg?r

 

 

 

I have cut out my circular 65cm diam. ground board from a completely waterproof material, a hard type of plastic, it is tough and flat. I have enough Baltic ply to do the job, but will try this first... 

 

now it is time to start the rocker box... and the trolley...

 

Must press on!  Thanks for looking! ??

 

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Tweedledee

That looks great Steve. Nice idea with the "fast" levelling feet. :thumbsup:

 

I'm intrigued about your tough plastic waterproof ground board material.

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Smithysteve
1 hour ago, Tweedledee said:

That looks great Steve. Nice idea with the "fast" levelling feet. :thumbsup:

 

I'm intrigued about your tough plastic waterproof ground board material.

Hi Pete, I was told what the ground board is made of, it is not a common name, anyway I can’t remember now ... it is like Formica, it took me 2hrs to cut that circle out with a jigsaw! It is/was used to portion off shower cubicles etc... I will show you the next time you are passing. I was sceptical myself, but a fellow astro buddy has used it on his dob with no problems...

 

the fast feet should save on time spent winding! ?

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