The Giant Binocular

2 thumbs up!!!

Keep up the great work and posts
 
I feel like you need a Miniature Schnauzer to help you with those rats!
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Robert
 
No worries, I will be showing the whole process fron grinding, polishing and testing the mirrors.
Just need a supplier of round tuits.

Round Tuits, that's what I'm missing, i knew there was something I needed, just never had time to find out what, If you find a good supply let me know.
 
For want of a shoe. Or what I've been doing for the last three weeks.

Needed 4 chunks of aluminium for the altitude bearings for the bino.
Guess I had better cast some.
Hmm, floods and rain so better not.
so I knocked these out for the secondary mirror adjusters.

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Just have to silver solder the brass nut to the brass plate, its a larger version of what I made for the tertiary holders. BUT, my gas torch wouldnt quite get hot enough for a good joint so cant finish them off, Gaaaa.
Need a bit of brass for the remaining adjustment screws, none here, I know, cast some, oh, I cant its still raining, bugger, getting totally fed up with it so a change of tack was called for.

I had a go at turning a crankshaft, I dont have a use for it (yet) it was just for kicks to see if I could.
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Got this far then Whoops! crashed the tool onto the chuck and snapped the belt and the parting tool. They are now on order so what can I do now?
As its still bloody raining I still cant cast anything but I suddenly had a light bulb moment, maybe I can machine down these horrible failed castings for two of the bearing blocks.
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I started facing off the bottom of the bowel as the other side allowed (sort of) clamping.
The centre is only just there to help prevent it from moving towards the tailstock.
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Then I thought why not cut the ends off with the table saw
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Now I can use the rear face of the jaws or chuck to get parallel faces then square up for the other two sides then the ends.
Many many hours later and half a ton of swarf
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these materialised.
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The arrowed corner will be rounded eventually which will remove that unsightly bit then I may powder coat or polish depending upon how I feel.
From what I thought was a totally buggered up melt came the best cast aluminium I have ever poured, not an inclusion to be found. Just goes to show.
Oh for a mill or shaper, perchance to dream, the lathe certainly got a real flogging getting these down to size.

Ahh, the rain has stopped, the water damage has been repaired and the land is drying out.
Ta Da, casting time.
Out with the muller and prep the sand.
Not a chance, the motor has failed.
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I have a 1/4 horse I can "borrow" from the mulcher so I've cut the old brackets out ready to re build.
A major problem is the motor is rated at 2850 rpm. Thats a lot of speed dropping to get down to 30 rpm.
I can make some new pulleys and whack a jack shaft in, hang on, I need the muller for the sand so I can cast the pulleys.
Guess I had better spring for a new slower motor, found a 1/3 hp 900rpm for $140AU all up so I think thats the way to go.
They say in never rains but it pours, weve certainly had that in spades of late.
Now how do I get this purchase pass the financial controller???
 
Charles,

You said:
Many many hours later and half a ton of swarf

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but the chuck jaws are totally empty!
At first, I thought maybe you got really carried away........making more swarf for more casting......

okay, enough smart a$$ comments, a few real questions:
Did that "bowl casting" crack in half as it cooled?
What's the plan for more heat for silver soldering?

(okay, just one more smart a$$ comment......I thought it was hot enough down there this summer that your solder would have been running off the shelf.....)

-brino
 
41'C was way too hot for me but its nice now, about 32.
The bowel of aluminium started leaking where it dissolved the stainless steel.
I cut it in half on the table saw ready to re melt but these blocks were just the thing.
I would like to get one of those oxy/map sets but cant squeeze $400 out the retirement fund so I'm unsure what I will be doing.
 
Sav, Could you use your forge to heat the brass for soldering or use it's burner if it is gas fired to heat the large piece of brass and use your torch on the nut. A handy sil-sol paste can be made with 5-15% sil-sol stick (bunnies) and some flux mixed about 50-50. File the stick to get the powder or use a die grinder or Dremel with a carbide burr (much quicker). Bunnies also sell a small roll of what (i think) they call Plumbers solder with matching flux which has a much lower melting point than ordinary sil-sol but is much stronger than ordinary tin-lead solder.
Nice to see you made use of that Ali. You really manage to get some oddball parts in that poor lathe.
John.
 
I have 4 grades of silver solder - ultra easy, easy, medium and hard. They have different melting points so multiple soldering operations can be carried out.
So far I've only used the hard. I will try two torches next as that may do the deal. Failing that then its the forge burner but that will be well over kill:laughing:
 
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