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Discovery 17.5 splitube Dob base

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#1 Tim Gilliland

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Posted 24 October 2012 - 02:18 PM

I am in the planning stages of rebuilding my Discovery Base. It was a bit on the weak side from the begining and I made a few modes to stiffen it up. I also added wheels and handles, and a EP and accessory holder. The mods work fine but were done on the fly and the end result is ugly.

So my question is, are there any tips I need to know about building a copy of my current base but adding the mods. Seems pretty straightforward. I have a small woodworking shop and am reasonably experianced as a hobbyist woodworker.

#2 gatorengineer

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Posted 24 October 2012 - 07:18 PM

Couple of suggestions

1) buy quality multiply plywood not homedepot stuff, while it will work its full of voids.

2) Consider lightening holes, and accessory trays, and possibly a stalk for a phone for sky safari or the like

3) To go along with 2), go ahead and do encoders now, becarefull to arrange things so the wheelie bar handles dont interfere.

4) There was an ingenious guy who used large 6" or so pipe clamps on the wheelie bars to give a handle at a more convenient elevation

5) If you have the small bearing discovery, contemplate an adjustable tension strap if you have balance issues (discovery made a few different 17"s so I dont know what you got and how it works...

6) Russ sackett has posted on cool finishes if this is your thing.......

Most importantly have fun...

#3 Tim Gilliland

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Posted 24 October 2012 - 07:42 PM

1. Will do.

2. Had already planned on lightening holes accessory trays but had not thought about a stalk for the Ipad, thanks for that.

3. Already have encoders, will be careful.

4. Will look into the 6" clamps, thanks again.

5. My scope has relatively large bearings.

6. I will look at this also. It's kind of the purpose of the build. Scope works now, just ugly.

Thanks for the helpful suggestions.

#4 Pinbout

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Posted 24 October 2012 - 08:08 PM

how are you going make your joints, biscuit, nail gun?
waterproof glue, titbond III?

how are you going to do the pivot bolt? re-use, astrosystems?

so if your re-using the alt bearings, the bearing color/grain will have to compliment the box colors/grain.

#5 Tim Gilliland

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Posted 25 October 2012 - 05:35 AM

how are you going make your joints, biscuit, nail gun?
waterproof glue, titbond III?

how are you going to do the pivot bolt? re-use, astrosystems?

so if your re-using the alt bearings, the bearing color/grain will have to compliment the box colors/grain.



I will use biscuit's.

Did not know about Astrosystems for a pivot bolt, thanks I will check them out.

Planning on refinishing the altitude bearings.

#6 Tim Gilliland

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Posted 04 November 2012 - 10:54 AM

Ok, so I am getting started. What is the accepted laminate for the AZ bearing surface. Is there a supply of Ebony Star? It will have to be full size. A ring like is advertised on scope stuff won't work. I mount my scope on a platform each time I set up which entails positioning the center bolt by sliding the scope around just a bit.

#7 Tim Gilliland

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Posted 03 December 2012 - 09:38 AM

I am well into this now and am wanting see some examples of wheelie bars on larger standard Dob base's. My scope is a solid tube so the truss tube examples would not apply. Anybody have any link's or pic's ?

#8 Project Galileo

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Posted 03 December 2012 - 10:29 AM

Ebony star can be found but you will find it very cost prohibitive. I use Formica 909-42. 909 is their black modifier, -42 is their Crystal finish. You can get other colors but the Crystal finish is what you want. I have found it to be buttery and smooth and indistinguishable from ebony star when used with PTFE pads. It is used by many others too. It can be ordered at Lowes for in store pick up. Also used for the bottom of the rocker box is FRP. It is readily available in most home centers. It only comes in white or light grey. I have an extra 24"x24" piece if you are interested in it. If you use FRP most dob builders recommend using slightly larger PTFE pads with it.

Clear skies and have fun!

#9 Tim Gilliland

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Posted 03 December 2012 - 03:30 PM

Thank's for that, I have the base effectively built just need some help with the handlebars and wheels. I did use the 909-42 laminate. I will pop over to the reflector foram and look at some photo's of what other's have done.






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