Alan64

The leg assemblies are now ready to be dyed; and yes, the brass is quite flat and conformative to the wooden surfaces...

On the flip side of those overlays, the brass, but the edges of the wood must be dyed first, as there'll be no dyeing where that epoxy touches; same with wood-glue, but I didn't want to dye around the maple overlays, as the glue might not hold in that instance.  Why take the chance.

I cut the dye, half to half, with denatured-alcohol, and it's still a bit dark...

I may use two parts of the alcohol to one of the dye, but I'll need to test that first.

I did the last three in one fell swoop, whatever a fell swoop is. Now, those overlays are lighter than the legs, and I want them inconspicuous, so they'll get a double dose of the dye...

Now for epoxying the brass...

Three are not done...

...but three are.  You can't rush these things, you know.

The grain of the maple runs perpendicular to that of the lauan, or meranti, whichever, and for added strength.

Maple...

14 hours ago, Stu said:

How do you shape all these lovely washers and shims Alan?

After the drilling and cutting-out, you tidy up the rough edges, oft very rough, with a rotary-tool and a small sanding-drum; then sandpaper and steel-wool to smooth and polish, and by hand.

Time-consuming, but it is what it is if you want it...

Lovely brass, although not quite as lovely as bronze...

The cut-outs have been shaped, and all the pieces sanded down.  Here they are in the same box within which they were stripped...

Now to cut out the brass...

The first, actually second, set of legs has been prepared further, sanded down, numbered, and in preparation for the brass, then the dye...

13 hours ago, LukeSkywatcher said:

EQ1.....

The stuff of my nightmares.

*Shudder*

Indeed, and as they fall off the barge from overseas.  Aside from the need to finish it, the trick is not to overload it, and then to enjoy an ultimate in grab 'n' go.

The mount-head is done for the most part; just a few odds and ends to which to tend...

...like clamp-screws for the saddle, a lock-nut for the latitude bolt, a lock-washer or other for the latitude-clamp; little things like that.

My, it certainly is a diminutive, li'l darling...

Incidentally, that Coke can is two years out of date, and it seemed swollen a bit, so I took it outside and threw it up into the air onto the road, then threw it in the bin.  I didn't want it to explode one night whilst I slept.  Now I don't have me prop.

Today, I'm working on my legs...

I have to get those cut-outs just right, and then epoxy that .010"-thick brass over each, a total of six.  I may apply  something or other over the outsides as well, and to further strengthen the wood there, since it's now thinner.

I wonder if I should dye the legs first before applying the brass...

Thanks all.  

With the RA-clamp locked, there is only half of a millimeter, if that much, of movement in either direction; not nearly a full measure of same.  I may then hold the mount with one hand, and with a little effort twist the worm shaft with the fingers of the other, and round it goes in a complete circle without a hitch; nothing short of marvelous, the motion.  I removed the steel washers from the axes' lock-nuts, leaving only the bronze washers, and I must say the improvement was rather noticeable afterwards; those rotten steel washers, they're history now.  Also, I feel that I used PTFE as a shim for the stepped RA-bore...

...in a pinch, with the now-obvious and most preferred solution having escaped me at the time.  The PTFE shim was .015" in thickness, so I made two shims of .008" phosphor-bronze, and for a total of .016"...

I made the inner shim 1mm shorter than the outer...

...a more solid interface, and it shows when testing the axis.  Incidentally, PTFE is subject to creeping, spreading out over time, and what amounts to nothing more than deterioration.  Hindsight is not only 20/20, but also most fortuitous.

I don't think I can add or do a single, solitary thing extra to these axes.

I had to cut down the right-angled portion of a hex-key to batten down the bolts.  Anyhoo, I had gotten three of these smaller bronze washers for the worm assembly...

...but I needed only two in the end; one polished only, and one with its O.D. ground down in order to recess into the hole of the threaded yoke...

The one that's recessed is barely visible on the right...

The motions throughout are most satisfactory, but I do expect that it will need a tweaking here and there once a telescope is mounted upon it.

Earlier, I took the block and the bolt with me.  I went straight to the standard nut-checker and...<drum-roll, please>...

...10-32...

Being that this is a Chinese clone of Japanese design and manufacture, why isn't everything in metric???

I would like to extend my thanks to Themos for urging caution when working within this area of the mount-head, for it is of the utmost importance not to torque-down the bolts when reassembling.

Drat, the longer bolts will not thread inward.  I took the original bolt with me and fed it into the nut-checker.  Later today I will take the threaded block itself.

8 hours ago, themos said:

Just be careful with the worm holder, I've had mine break in bits. 

Oh, I'm always careful, save for that one time...

The outing today was successful...

The originals are 12mm in length, whilst the next size up at my local hardware is 20mm, so I thought about lock-washers in addition.  The bolts turned out to be M5s, and as I had suspected.  I may have to cut them down slightly, I don't know yet.

The DEC-control components, before...

...and after...

The spring and the actuator are noticeably cleaner.  But the insides of the two housings for the spring were rusty, particularly the larger.  You can tell by the outside surface of the smaller one.  I didn't take photos of what I sanded and scoured out of them, as I'll leave that to your imagination.  I did spend at least an hour doing so.

The components freshly-lubed and installed...

In hunting for my aluminum stock, I ran across this aluminum yardstick that my father had exposed to some sort of solvent which erased about half of the indicators, so I thought, "Why not?"...

It just so happens that with the thicknesses of the yardstick and the thinner sheet combined, the two measured out to a total thickness of, believe it or not, 2.5mm or 1/10".  Actually, from end to end, an average of 2.7mm, but who's counting...

But as fate would have it, the bolts to fasten the assemblage are too short.  That means yet another trip to my local hardware at the county seat, but I don't mind as I love the place.

There was a rather thick layer of paint on the worm-block's mating substrate as well, and tenacious...

I would assume that the horizontal and vertical centers of the worm should mate and mesh with same of the RA-gear, and as precisely as this level of manufacturing will allow...

...a 2.5mm, or 1/10" gap.

I didn't realise that the paint was that thick.  

Yet again, I had to remove paint, from the worm-block's bottom surface and within all of the threaded and non-threaded holes...

The RA-axis now has its clamp-pin...

The depth of that hole is 12mm.  I made the pin 5mm in height. 

The DEC clamp-pin; out with the old steel one, in with the new one of brass...

That sort of looks like a steam-engine, and a train to the stars. 

I had second thoughts on using the clamping-knobs from the spare "AstroMaster" CG-2, as they just didn't look like they went with this "PowerSeeker" CG-2.  After all, I do want this one to appear as original as possible, and the original thumbscrews, now with the brass-pins, are not difficult at all to batten down or loosen.  These thumbscrews are, as a matter of fact, charming, and at the same time, subtle, tasteful.  No need for the flashy stainless-steel there.

They also match the thumbscrews for what will be the wooden legs for this mount-head...

I decided against a shim for the needle-thrust bearing, as the slop was only .010" all around.  Here, the RA bearing and washers are lubed and ready to go...

...and to fit against and into the RA bore with its finalised PTFE shim in place...

The bronze lock-nut washer...

The mount-head with the axes completed, and with the RA-gear cover installed...

The RA bearing and washers all nice 'n' comfy-cozy...

Next up, the worm assembly...

"Pickering, this is going to be ghastly!"