I thought I'd post my progress for my current build. This is my first attempt at ATM, and I have to give a big THANK YOU to mental4astro for all his advice.
As you might have seen, I've been selling off a lot of my gear as I'm getting out of imaging and back into visual astronomy. This is mainly because I simply don't have much time for this hobby anymore. So I began looking for a good dob... but in the end I decided to make a dob base for my 10" Sky-Watcher newt as this would be much cheaper and I hope MUCH better than cheap commercial dob bases.
So I came up with a plan with much assistance from mental, see attached plan. The cut outs are meant to represent celestial bodies. I stole mental's use of the large disc with a smaller disc on either side, this symbolises how Galileo first pictured Saturn. My design on the side is meant to resemble a moon disappearing into the planets shadow... but looks a bit more like a snowman!
So to date I have cut out all the parts and have them sanded awaiting assembly. I'm using 15mm marine ply and I've sourced virgin teflon AND secured a massive sheet of ebony star (must be the last piece in QLD!!!). I was stoked to find the ebony star, I rang around and visited loads of kitchen places, in the end I went to a benchtop wholesaler and the foreman found their last piece tucked up the back of the warehouse, its 650mm x 2.2 meters long! And the best bit... I offered $45 as it was old stock and they happily obliged!
My plan is to stain a medium walnut colour and finish with satin exterior poly. Also I've purchased an Argo Navis that will be installed. Not sure yet how I'm going to mount the handset....
I've been enjoying the build, this is my first time cutting circles with a router, but after using my brother's little laminate router I simply have to have one!
I did a dry run with the scope to make sure it was all going to go together as planned. Happily everything fits together beautifully and I experimented sitting at the scope and using it at various altitudes and its very comfortable.
After the dry run I glued up the rocker box ensuring it is nice and square.
In the first pic showing the inside of the rocker you can see a side brace I've made to help strengthen the tops of the cradle (good suggestion mental). I made cutouts in the corners of this brace to allow routing of cables.
I also did a stain and varnish test run on some offcuts today, we'll see how they look tomorrow
Big fan of the 10" Dob for capability and mobility. Your mount looks very professionally crafted and unique. I love mental's Dob bases and I love what you have done here. The timber looks great with the blue Newt.
Thanks John, I too think the 10" is a good sized scope, and the biggest I'd get in a solid tube. A 12" collapsable is temping though.....
Thanks Alex, its funny, I also find that brace very nice to look at
You think YOU can't wait for it to be finished!!! I'm dying to complete it. I've been on holidays this week, but back to work on Monday so progress will slow sadly. But I'm hoping to have it assembled by then and the finishing started at least.
Thanks Stu, yes I'm hoping this base will last many years - the marine ply is beautiful stuff, its a 9 ply and machines nicely. I've got an Argo Navis sitting on my desk and can't wait to fit it. Gary has been amazing helping me plan my base and the argo install. He even custom made me a pivot bolt to my dimensions!
I'm really hoping this will be a smooth and pleasurable base/mount to use, it will end up being worth more than the scope!
Not a lot to report today, I glued everything up and cut the azimuth pivot holes. The pic attached shows how I ensured the rocker was exactly centred over the pivot hole. I used fine copper wire and strung it corner to corner - easy. Finally I wet all the timber down (to raise the nap) and I'll give it a final sand tomorrow before staining the lot. Hopefully I can cut out the laminate too, ready to be glued once the varnish is on.
Well, I've moved the project out of my brother's shed and I'm back home to finish it off. Here is a pic showing how the grain is looking after the first coat of poly. I'm quite happy with the look.
I've almost finished gluing the ebony star into position - the azimuth disc is done and only one alt disc remains to be trimmed (the other is ready for more poly).
Then its just 2 more coats of poly, some teflon and its finished! Can't wait!
Well here it is! Its not quite finished yet but I couldn't help myself, I had to assemble it to test out the balance and teflon positioning.
It currently only has 2 coats of poly, and I plan to put at least one more on, probably two.
I'm VERY happy with how it has turned out and it looks like it will be a pleasure to use. A big thankyou to Alex for all his help during the planning stages and putting up with all my questions during the build.
One issue I discovered today is that the discs don't attach to one side of the scope perfectly square so will need some careful shimming.
One thing not shown in the pics is that I have attached some ebony star to the inside of the discs so that I can place a small tab of teflon on the inside of the cradle to eliminate sideways movement of the discs. Attaching these and the alt teflon is all thats left to do other than more coats of poly. Oh and then I can mount the Argonavis. Once the mount is finished the OTA will be next to be refurbished, I have a FT focuser and plan to get the OTA powdercoated, but what colour????
Thanks everyone for looking and your support. I can't wait to get back into this hobby and enjoy visual observing once again!
Colour suggestion? First is leave it as it is, then maybe metallic gold/manganese. The blue works well with the stained ply. I wouldn't go white or black. Maybe even one of those two tone paints that change colour in different directions. If you're going to go to so much trouble then make a statement. You can always have it sprayed to look like a cannon, laser or rocket. The last two would really endear you to the Spooks if you take it to a public place!
I've had a bit of a think about your alt disks. You've only got a couple of screws holding them in place. With the load they are supporting the will always flex out. Look to strengthen the coupling mechanism to the tube rings as that is the weak spot. That's the reason why I prefer the more cumbersome looking box-cradle around the tube that holds the alt disks - no flex then.
Maybe if you fashion a plywood arc to act as a third tube ring that only reaches over the top of the scope to give you a third point along the top of the disks, this will stop the flex.
Thanks Alex for your kind comments And I too think I should do something interesting with the tube colour!
The alt discs actually attach to the tube rings very securely and rigidly as there is a flat mounting pad on the rings. Once screwed on tight there is far less flex in these parts than in other areas of the mount (which only has minimal flex). I will need to ensure they are square though. I'll give it a try as is, I can always fashion a support bar that goes between the discs and sits under or over the tube (or both). I'm not sure why they didn't go on square today, when doing a dry run early on they sat very square, so maybe I just need to be more careful doing up the screws.
Hmmm, first light on 47 Tuc after alignment? Then push the puppy for the Grus Quartet centred on NGC 7590. Then across to NGC 1365 should be a good test of your build coupled to the Argo, . Pin these three and you've got a monster set up! Not a challenge for the scope, but their spacing will.
Dave, your build is a joy to the eye. The lines, curves, geometry - lovely, mate.
Dob Base Build 10"
(must be the last piece in QLD!!!). I was stoked to find the ebony star, I rang around and visited loads of kitchen places, in the end I went to a benchtop wholesaler and the foreman found their last piece tucked up the back of the warehouse, its 650mm x 2.2 meters long! And the best bit... I offered $45 as it was old stock and they happily obliged! 
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