Mirror's arrived and now the fun starts

[Astroman]

Looks great, Phil! A bit of overkill on the plywood thicknesses, but that's usually a good thing in this case. (I generally make the annulus out of 12mm and the back board 18mm and it works just fine, but more is better.) Well done.

[geppetto]

Thanks guys..

AM

Can I pick your brains..

Regarding siliconeing the mirror to the ply ring.

Did you use three pads of silicone at 120 degrees or some other method?

[FLO]

Looking well Phil. You've got more done in 4 days than I got done in 4 years!!!

I assumed there was a shortage of MDF up your way

[GazOC]

MDF? The elbow grease shortage affected the job far more.....

[Astroman]

Three pads of silicone at 120º is ok for smaller mirrors, for a 12", I'd go, (and did, for a 12.5") with 6 pads at 60º. That scope is still going strong. Just make it fairly thin, and don't push it too much when setting it on there. Let the weight of the mirror do the trick.

[geppetto]

Thanks for that AM

Will go for the six pads at 60

A suggestion that I read somewhere was to put lollipop wooden sticks

between where the silicone pads were so that the mirror lowered onto those

whilst compressing the silicone thereby insuring that the mirror sits level with

the plywood.

Then, withdraw the sticks after the silicone is cured.

Might again be overkill but it seems to make sense....

[geppetto]

Bit more done today.

The mirror is sat on its silicone pads and curing nicely.

Got the front OTA box put together and mounted the focuser

and secondary.

Next job is to fit the trusses and then with the primary in place, I can slide the

front box up and down till I find focus.

Truss poles can then be cut to size

[Kaptain Klevtsov]

Great job Phil, it's coming on in leaps.

Captain Chaos

[Astroman]

Lolipop sticks sounds good, but I think tongue depressors are more uniform thickness. I used them as shims on the rollers in the dome. 8)

[geppetto]

Good day with the QDD today

Cut the truss poles and mounted the mirror on its cell.

The silicone is holding the mirror rock steady.

Was going to leave it at that for today but excitement took over and I just had to have

a look through the beast.

Screwed the poles on (will be bolted later) and fixed the cell with mirror into the bottom OTA box.

Slid on the front OTA box and set up the secondary to the focuser using my barlow.

Put the laser in and tweaked the secondary to hit the primary and finished of by

collimating the primary with my barlow (and somebody to turn the wingnuts )

Collimation went perfectly so I had to drag it outside for a looksee...

Propped it on a table and pointed it at Bolsover castle up the hill and WhooooHooo thar she blows :D

Took a quick image with the Nikon to mark the occasion..

Long way to go yet but its lookin good 8) and big :shock: 8)

[GazOC]

"First light" as they say. Nice one mate!!

[Kaptain Klevtsov]

Yeah, nice one mate. Can't wait for a "first dark" report.

Captain Chaos

[GordonCopestake]

Looks impressive. I look forward to seeing your mount (and ladders!)

[geppetto]

Gordon

Hoping not to need the ladders

As it is, stood on its end on the floor, the focuser is 3 inches below my eye level so

with a bit of fiddling and a very low profile mount I might get away with it 8)

[GordonCopestake]

hehe, we'll see

[geppetto]

Could always get some platform heels

[GordonCopestake]

lol, i can just see you starting a new fashion

[justin138]

Phil, that is the business! I may just nick your design for the Smellyscope (if you don't mind of course!)

Totally off topic, my father in law used to live just down the road from you, in Shuttlewood, and we went round Bolsover Castle in the fog one day, nice piece of history you've got there and the only place I've ever seen bullfinches.

<Ramble over>

Justin

[geppetto]

I may just nick your design for the Smellyscope

Nick away Justin nothing original in this..

Yes, Bolsover has turned into a nice place to live and the castle brings

revenue to the town...

[geppetto]

Yet more done today

Roughed out the parts for the DOB base in 18mm MDF.

The two ALT bearing blocks are 12" in diameter and are

two thicknesses of MDF each. The blocks will have Formica glued to the edges

to make a good slippy surface to mate against the teflon blocks.

When all is set up and working, I will route out shapes in the base side walls

to reduce the weight and also to pretty it up a bit.

[Jaffa007]

I would just like to say what quality job you've done so far. 8)

Keep up the good work! Look forward to reading more & seeing the final result.

James

[justin138]

Good work so far Phil. Quick question, where do you get the Formica strip from to do the alt bearings?

Justin

[geppetto]

Justin

The formica strip is what you get for gluing on the ends of kitchen worktop lengths and is included in the pack.

Never seen it sold separately but generally I had used the metal end plates on worktops in the past

and I saved the formica strip in case it came in useful... which it has 8)

[Zeffer]

Is this any good to you?

http://www.astrobuysell.com/uk/propview.php?view=8884

[geppetto]

Funny that, just been looking at it earlier on...

Thanks for the heads up Zeffer