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Alan64

Celestron PowerSeeker 127EQ

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For several years, I had read of the dratted and dreaded "Bird Jones" telescopes.  They come in a few different apertures, and under a few different marques.  I decided that it was about time to get one for myself; so I did, and last February...

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1253906876_Vixenstyle2.jpg.371d60567d0373e4b53dfb327ab16f2b.jpg 

The bundled accoutrements...

accessories.jpg.a030b709b338f11e2385b8b851ad3829.jpg

The 20mm erecting-eyepiece is a rather bizarre inclusion.  The 4mm I didn't take seriously; that is, at first.  The 3x-barlow no doubt will introduce false-colour, therefore it has not been and probably will not be used.  The 5x24 finder-scope isn't all that bad, I've found; for a 5x24, but it will not be used with this telescope.

I have read every review, and a vast multitude, of this kit that I could find online, and watched videos as well, yet after I bought the telescope, instead of before.  I bought this one, not unwittingly, but on purpose, and whilst knowing all about it already.  Quite a few purchasers like this telescope; but most, I think, do not.  Mind you, they want to like it, to love it even, but if it arrives mis-collimated they simply cannot collimate it.  If they don't end up returning the kit, which many have done, they display it within their homes, as a decoration, and forever mis-collimated.  The telescope is an economical alternative to a Celestron C5 Schmidt-Cassegrain.  Indeed, I refer to this star-box as my very own "C5".  It is that aspect, the short, compact tube, and the oft low, low price of the kit, that draws those first starting out, beginners, like proverbial flies.

Why, even my own arrived mis-collimated...

Polaris.jpg.78a99e03bef23f7dc449d14bddd7b4b4.jpg

That's supposed to be Polaris, the north star.  Instead, it looks like the devil's own pitchfork.

  • Sad 1

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The kit also included Celestron's CG-2, an EQ-1, and the smallest equatorial on the planet...

mount5.jpg.81f95a6e00ff8f041233de89ff6acd1d.jpg

Can you see it there?  It's just as spindly as the wintry branches in the background.  The counterweight for it is enormous, and far too heavy for this mount...

counterweight.jpg.132340f3fb88c58590a7651ff4ed1501.jpg

...but necessary to counter-balance the telescope.  But this mount will not be used for the telescope; rather, for my smaller telescopes, the very smallest, and with smaller, lighter counterweights.  What I did to the mount was done before this project.

And now, what I did to the telescope itself...

Edited by Alan64

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Hmm, the cowling of the telescope; it has four, quite thick, spider-vanes, or -stalks rather...

obstruction3.jpg.836d1682b3695b6387d42c7522f610e8.jpg

That's the collimation scene upon arrival, there on the right.  Does that look right to you?  It looks a bit off to me.

The front of the telescope; it's reminding of a jail-cell...

BOxUBaZ.jpg

...and in imprisoning the primary-mirror, and a spherical one at that.  This telescope is actually, incognito, a 127mm f/3.3 to f/4 Newtonian.

cowling2.jpg.6b2f2c961da4d32a3af4d4c8db6859b3.jpg

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No center-spot on the primary, and to be expected...

1488615411_nocenter-spot.jpg.01aa9bbfb4dff85f0093b3893fa77448.jpg

My, it certainly is shiny within, no?

I encountered a problem with the cowling, the secondary-hub specifically...

1453803494_hubmisalignment.jpg.3db4a8294b807c7fb1ac7fd69c403b42.jpg

Not a single one of those set-screws were aligned with the focusser, and with no way to adjust it...

1152572262_hubthreads.jpg.e69a7a279b498b2697c83e189ce97f33.jpg

I saw threads, so the hub must unscrew.  But with all that factory-paint, and the hub no doubt glued in place beforehand, that wasn't going to happen.  There's only one thing to do...

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This, an eco-friendly paint-stripper, and most effective...

stripper.jpg.16b120692967556c37c43ffa7fa15729.jpg

stripper.jpg.6d3656728109794dcfada4aeb4db813b.jpg

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That's a rather nice piece of hardware, but I still couldn't unscrew the hub.  It was glued in place after all.  So, I took it outside, along with a mini butane-torch, and heated that area all over.  I then took it inside, and after a few pulls with pliers round the rim of the hub, to the left, it broke free...

cowling7.jpg.4893abdf4ac907717bd92aa36b2f8968.jpg

Indeed, quite a nice bit of hardware, but why, and within this cheap kit?

Incidentally, this is the exact same cowling as that found on the Sky-Watcher 130mm f/7 Newtonian; the 130 it's called, and also with a spherical primary-mirror.

Edited by Alan64

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How many would you remove?  Just one?

cowling3a.jpg.c4d5d968313e589913935d5ad051bebd.jpg

Two...

cowling3b.jpg.089b398785ab954c45205513450cd6de.jpg

...or these two?

cowling3d.jpg.08e7f22762e0b8f37a8d1f717ee4fb6e.jpg

How about three, rather...

..cowling3c.jpg.9011c940431c0c034059e60d8e50b402.jpg

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The number of vanes makes a difference in the number of spikes that will show in a star image.

DFCCC503-6EF2-47E5-B9EE-123A263C1526.png

Edited by johninderby
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I worked from the front to the back of the telescope.  Since the cowling is at the front, that's the first thing to work on.  During it all, not even a single pebble was left unturned.

I couldn't wait to start cutting out the stalks...

cowling8.jpg.99748017ab852cce4e572c145c724536.jpg

...and that one opposite the favoured one, and for the next step.  Hot-rolled steel, from my local hardware...

steel2.jpg.2c71265bef8ac4e13dd337d5c80e443c.jpg

"Made in USA with Global Materials..."  What does that mean?  Do you folks ever see "Made in UK with Global Materials" on the products you purchase?

I took the whole flat and ground down one end with a stationary belt-sander...

stalk3.jpg.81e2cfea8c9cd7bc79cffbfd138ab5f5.jpg

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stalk.jpg.c0cc3ba8e318cf6aa5e734db0af28808.jpg

You can see how weak it is there where that stalk joins the frame.

With the steel splint removed from the flat, I used the stalk that I had cut out, as a pattern...

splint2.jpg.923d944d0bc54e675a692643860fcc27.jpg

splint3.jpg.ae46180e7723995d127c8ac994e1504b.jpg

...and to match the curvature of the top of the stalk to the underside of the splint; close enough.  Incidentally, the entire cowling is of aluminum, hub(anodised), stalks and all. 

In the splint went, slowly but surely...

splint5.jpg.688c3f2cc96f393a53983f978e901afd.jpg

In, at last...

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The splint should not be hammered in snugly, or tapped in either.  It must be fitted somewhat loosely so as not to deform the hub's alignment.

Edited by Alan64

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The top of the favoured stalk and the underside of the splint were scored...

splint8.jpg.3076a7dfb281ec65b5d924f438e0aef7.jpg

I then glued the two together with J-B Weld steel-reinforced epoxy...

splint9.jpg.b7bc6b804bc6191b2dbda136894f20b3.jpg

The bronze tab jutting out there on the left is a "key", and to align the splint whilst the epoxy cured.

After sanding...

splint14.jpg.0a571613ab4ad6a51031282c33987d6a.jpg

splint10.jpg.95bf1aed04087c7cedf6cdc950ce5423.jpg

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Oh no, that's not all.  I couldn't just glue those two together and leave it at that.  The two had to be made as one.  Bronze...

786764170_bronzeplates.jpg.9d0ee0aa7f3f53d5be1569cbe2441e2c.jpg

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Oak and hard-felt were used to ensure that the bronze plates conformed to the sides, and with no lifted or raised edges after the epoxy cured.

Perfectly flat...

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The two were made as one.  With that done, the remaining stalks were removed...

cowling9.jpg.f025f62f62b4a3989ba56bedfd60329e.jpg

Edited by Alan64

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The hub was then glued back in place, but with 5-minute epoxy...

cowling11.jpg.d0800b99e264f2c56b5a555020c7b73b.jpg

...and with one hole for a set-screw aligned with the stalk, also the focusser, and as it should be...

corrected2b.jpg.08d94f7aac81efa20a5616ecac6a43ff.jpg

The cowling was then sanded down, masked where needed, and primed...

primed.jpg.64d3b108f516c19c57938127adf8e06e.jpg

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The outside of the cowling was painted with the original glossy, hammered-black, and from a rattle-can; whilst within the cowling, that was painted with matte, chalkboard black...

cowling12.jpg.0d984dc2bbe4bc77d2d492a04f95d799.jpg

cowling14.jpg.d1e6a3b025eefc9ccb04508e8d2bedf5.jpg

Before...

before.jpg.0f151f3d16971c585fc4a027661ed142.jpg

After...

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Isn't that lovely, free and airy?  Only the two necessary-evils remain to obstruct the primary-mirror.

Incidentally, just before the modified cowling was painted, I had accidentally struck the hub, and the sound and vibration were reminding of a tuning-fork, but very brief; hence, very strong, that lone stalk.

Edited by Alan64
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After the cowling was completed, the next stop was the finder's base.  The post-screws jutting out simply wasn't going to cut it.  I wanted a Vixen-type base.  But first, that base would need strengthening, for rigidity, and to prevent deformations of the tube.  A galvanised-steel whatchamacallit, and from what was left over after we built our house...

1910669323_cornerplate.jpg.7ea237ca881cc81a68135f0ffe1a1d4d.jpg

My giant scissors...

aluminum2.jpg.ba2e4f8d4fe3674327d58e3c2844a514.jpg

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The galvanisation removed...

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Forming...

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The plate was then painted...

1567627923_backplate8.jpg.b3cd3302a9557cd0a97e00216cd52e0b.jpg

...and flocked...

1632197880_backplate9.jpg.7323f4677641e0daa2fd697db91d26f5.jpg

The edge of the plate was then matte-blackened all round.

Edited by Alan64

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The tube was emptied out, utterly, and clear-glossed...

413104019_tubeglossing2.jpg.eedb3b71a5413b0c97b20394c7c22233.jpg

Flocking with Protostar...

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The flocking covering the tube's holes was carefully cut out...

flocking25.jpg.0aaaf607405f2d3ebda18a663757675b.jpg

...then the finder-base was installed, and that portion of the hardware within blackened...

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Next up, Synta's wonky, plastic focusser...

focusser3.jpg.050df86d5d2cbcf62abe0d55d2ca2811.jpg

The basic focusser exploded...

focusser4.jpg.37f38167b1d3fd5c42c1ad3af26dc287.jpg

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I got a total of one, a single corrugated-plastic bearing for the drawtube.  Note the molding-marks, and numbered.  #1 is raised, whilst the other three are recessed.  #1 was ground down flush, along with excess sprue all round.  The last thing I needed was seating problems.

A triad of three PTFE strips were installed as bearings for the drawtube...

focusser9.jpg.ca4a1114c1d934044419d3b2388a5438.jpg

...with the racking in and out straight and true, freely and butter-smooth, and no binding or slop whatsoever.  Even when barely and gently twisting the knob, back and forth, the drawtube would move, instead of a dead spot.  That, yet another successful renovation of yet another of Synta's "masterpieces"; most successful in this case, as others have exhibited a slight dead spot when racking.

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Ah, but that is no ordinary focusser, as its drawtube contains a cemented-doublet, presumably a corrector for the spherical aberration inherent to the spherical primary-mirror...

1525727182_doubletcorrector2.jpg.9f3f66b0f32892b5d1a42d88d85d6b25.jpg

There are a few tutorials on how to collimate a "Bird Jones".  All require that the corrector be removed, then to collimate the telescope in the manner of a classical, traditional Newtonian.  But it is indicated within those tutorials to remove the doublet itself, and leaving its cell in place.  Rather, it is far better and best to remove the cell and its doublet, both, together...

doublet9.jpg.6c30047697bd13e97bc4e91d4062072f.jpg

The last thing you need is to have the cell in place to narrow the view during collimation, not to mention either flipping, losing or soiling the doublet if removed from the cell.  I blackened that portion of the drawtube that juts into the light-path, and with satin-black instead for less friction when racking in and out.  Also, the tip of the rack was flocked.  No need for a wee mirror aimed directly at the primary...

drawtube9.jpg.3559700ca0765b7da08e72655077a4b4.jpg

This is the only drawtube that I have flocked.  With others, I didn't care for the flocked framing when looking down the drawtube.  But in this case, the doublet's cell plugs up that end, so I glossed then flocked the tube's interior...

flocking8b.jpg.4f29893c69ce5f1ee6d7a7aa76bbdb4d.jpg

For the last piece, I made a pattern...

flocking11.jpg.1746cb8d5cd003ebde0455a0d03b09f9.jpg

Edited by Alan64

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26 minutes ago, happy-kat said:

Cracking work.

Begs for bigger turning twidlers on the focuser

Not at all, even at the higher powers, I've found.  The renovation is that effective.

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The doublet, the corrector...

doublet.jpg.2e84c2afe89535fef0f0607f1b7a41ac.jpg

Isn't it lovely?  That's what transforms my 127mm f/3.3 to f/4 Newtonian into my Celestron "C5".  But it needs work, don't you think...

doublet2.jpg.ec2e0934d92ae5cedc3e8b988604b37e.jpg

doublet3b.jpg.c0f73fbf3197244f4f73daa1a7fecb9a.jpg

doublet3.jpg.06c7c93e80d72568abab99faabe74784.jpg

Its cell was also blackened, where needed...

531935609_doubletcell3.jpg.05fdd2eb2224f9c62d3898fe33d0f7d2.jpg

...and with that, the focusser was completed...

doublet5.jpg.e0fc6b7f0c0d64f7d1cf3fb1629b9da3.jpg

focusser8.jpg.a9c8ced465d13db1fe312c18af577c2e.jpg

doublet3d.jpg

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Stunning write up, very impressive work.

Love to see some photos taken using the finished product.

 

 

  • Like 1

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1 minute ago, Kev M said:

Stunning write up, very impressive work.

Love to see some photos taken using the finished product.

 

 

The telescope is indeed finished, but mustn't spoil the surprise.

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Can you give me that Takahashi if you no longer need it then......😉

 

 

 

 

Edited by Kev M
typo
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6 minutes ago, Kev M said:

Can you give me that Takahashi if you no longer need it then......😉

 

 

 

 

Actually, we need none of our telescopes.  It's quite another thing in wanting one however...

FS-102v3b.jpg.c07849fb5983ada1c9a27800b52ecaf2.jpg

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