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large SCT badly damaged, can it be used?

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#1 cavefrog

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Posted 11 April 2013 - 09:00 PM

as in title... this has a secondary with a 3/4 inch hole worn completely through the coating in the center, and working its way out toward the edge. this is a C-14, just for proportions sake.
the question is, would it be possible to collimate with this much damage? I cannot seem to get any movement out of the center spot while defocused. it always stays at about 7:00, and flattened in the same area. the primary is damaged also, but not as much in percentage as the secondary. I think if it was just the primary damage, it would be useable (to what degree I could not say), but the secondary damage has me wondering if anything at all could work. am I just wasting my time?

Theo

#2 cavefrog

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Posted 11 April 2013 - 10:45 PM

no answers... anyway, I don't know, it may have been pilot error, but I got the collimation in focus somewhat. I went to the other side of focus, and started to get some results.
I started with a 31mm, then a 20mm, then down to a 9mm. It still doesn't focus very well. judgement was made in a very low (may be the focus problem) Orion nebula. not much contrast. I think I may need to look at something else, but need to rest my back right now.

#3 Starhawk

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Posted 11 April 2013 - 10:55 PM

Huh? Try a photo.

-Rich

#4 Steven

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Posted 11 April 2013 - 11:36 PM

What caused the damaged?

#5 tim53

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Posted 12 April 2013 - 02:34 AM

By damage, do you mean the coatings are oxydized or coming off? If so, you should be able to still collimate and try the scope out. If that's what the damage consists of, you could send the mirrors for recoating. You might want to consult someone who's removed the primary from its mount, as it might be RTV'd in place. I don't know about the secondary.

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#6 RogueGazer

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Posted 12 April 2013 - 03:29 AM

I would think you could collimate this poor scope in theory. If it were my scope I would gently tighten the 3 collimation screws all the way down and then back them all off 1 half turn. This should tighten things up and remove any possible slop in the secondary. After that go ahead and collimate with a properly cooled down scope and without using any diagonal. The image may look like doo doo even after collimation but who knows. :shrug:

#7 KerryR

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Posted 12 April 2013 - 08:55 AM

Why not remove the secondary and send it in for a re-coat? Not all coaters will coat secondaries with the backing plate attached, but some will. I believe OWL does, as does, I think, Spectrum. The primary could be done, too, but I'm pretty sure you'd have to remove it from the carrier, which, because it's glued on, is a big deal...



#8 cavefrog

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Posted 12 April 2013 - 09:03 AM

here's the photos. one can see what was the cause, and that it was not oxidation.

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#9 cavefrog

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Posted 12 April 2013 - 09:05 AM

I really wanted to cry when I saw this.

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#10 cavefrog

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Posted 12 April 2013 - 09:05 AM

the culprit in shipping.

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#11 cavefrog

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Posted 12 April 2013 - 09:21 AM

now there was a few variables thrown in here. I did not have any means to cool the scope, but it was out a couple hours. it was very humid, and I had to use a hair dryer about every 15 mins or so. even though I did finally get it collimated with a 9mm EP, it still does not focus very sharp. the secondary is, well... shot. one can see a chunk 1" long on the left side gone, and dead center coating is gone. would this be a problem? :) . no really, could this cause bad focus? I am surprised this works at all, that is why when I first could not get collimation under control, I wondered if it was possible to collimate at all with this kind of damage. there is a chunk out of the primary too. it is mostly out of the backside (2" across), and some of the first surface. about 1/2" x 1/8 inch.

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#12 cavefrog

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Posted 12 April 2013 - 09:26 AM

Tim... waddayathink? can it be recoated? I think I could file down that secondary enough to get some silver fingernail polish to stick! :)
seriously though, I did not have enough forethought to paint the crater in the secondary flat black. easily enough done though, it is fastar.

Theo

#13 cavefrog

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Posted 12 April 2013 - 09:32 AM

Hey Chris! ya out dere listenin'? I thought just too dang late about trying the laser for rough collimation. it wasn't utill I almost had it done , that I thought about it.
it would have been an opportune time to try out what we discussed. It fer sure couldn't of hurt anything.

Theo

#14 tim53

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Posted 12 April 2013 - 09:45 AM

Yikes! Was the scope insured in shipping? At the least, both mirrors need to be refigured. The chip at the edge of the primary isn't too bad, but the one in the secondary is so big it could have affected the figure. And the scratches can only come out by refiguring. If you're covered by insurance, I would contact Celestron a out replacing the optics.

Tim

#15 Starhawk

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Posted 12 April 2013 - 09:50 AM

Is this a new OTA? Any warranty option? The damage looks pretty bad. Yes, it could be collimated, but it will take fair amount of Tamiya XF-1 to keep this from playing merry heck with your contrast.

I agree, though- truly heartbreaking.

The Celestron option will be a new optics set at the bulk of the cost of a new OTA.

Otherwise, this one needs some earnest TLC to make it whole.

-Rich

#16 cavefrog

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Posted 12 April 2013 - 10:15 AM

yes, it was insured. just for grins and giggles, I called the "Tron". They said they need to examine the patient before they could give a prognosis. They would not give either a low or high estimate at the replacement cost of the optics. I know it would cost somewheres around $150.00 for one way shipment, so... end of inquiry.

Second hand purchase, but in brand new condition before shipping. :bawling:

Theo

#17 cavefrog

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Posted 12 April 2013 - 10:20 AM

Tamiya XF-1 ? had to go look that up. you think I should paint the center too , along with the big chip? not a joke...serious question.

Theo

#18 cavefrog

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Posted 12 April 2013 - 10:29 AM

Why not remove the secondary and send it in for a re-coat? Not all coaters will coat secondaries with the backing plate attached, but some will. I believe OWL does, as does, I think, Spectrum. The primary could be done, too, but I'm pretty sure you'd have to remove it from the carrier, which, because it's glued on, is a big deal...


glued on?? wow. I would think that would cause some problems with a mirror that big. however , I have never pulled a primary on an SCT, let alone a C-14. Think I'll leave that for when it really needs to be done, and there is no other way out.

as far as the secondary is concerned, it is a loss. any respectable recoater would laugh at this.

Theo

#19 EFT

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Posted 12 April 2013 - 10:37 AM

No way insurance is going to cover that. Even when the corrector is smashed they say it wasn't their fault and in this case, the secondary let loose and they will not consider that to be their fault.

Best bet is going to be optics replacement by Celestron, but it may not be cost effective.

#20 KerryR

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Posted 12 April 2013 - 11:58 AM

Why not remove the secondary and send it in for a re-coat? Not all coaters will coat secondaries with the backing plate attached, but some will. I believe OWL does, as does, I think, Spectrum. The primary could be done, too, but I'm pretty sure you'd have to remove it from the carrier, which, because it's glued on, is a big deal...


glued on?? wow. I would think that would cause some problems with a mirror that big. however , I have never pulled a primary on an SCT, let alone a C-14. Think I'll leave that for when it really needs to be done, and there is no other way out.

as far as the secondary is concerned, it is a loss. any respectable recoater would laugh at this.

Theo


The primary is held on to the carrier by the threaded central post that slides on the baffle (to allow focusing). A retainer threads onto that, pinching the primary between the 2 parts. The glue is used to hold the primary in collimation. As far as I know, all Celestron ota's are done this way. Meade's are not, or at least that used to be the case, which made re-coats and cleanings far easier.

Like the others, I think it's unlikely you're going to see insurance compensation because the issue was probably not due to mishandling, unlike, say, a crushed box and dented tube; this could have happened no matter how well the tube was packed. Sad, but I don't think the optics are ever going to work very well. At least Celestron can replace them with a new (matched) set, but that's going to be very expensive...

Not sure who should be saddled with this, you or the person you bought it from. Doesn't seem like you should have to eat all this-- none of it was your fault, and it sounds like the secondary may not have been tightened down sufficiently before shipping-- new scopes ship all the time without loosing the secondary. This would suggest a fatal error on the part of the previous owner... Yuck. I wouldn't want to have to deal with this. :bawling:

#21 jrcrilly

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Posted 12 April 2013 - 01:01 PM

Second hand purchase, but in brand new condition before shipping. :bawling:

Theo


That's a tough break for the seller - unless he tricks you into thinking that it's your fault he chose the carrier he selected, or the packing method he used. There's a reason that only the seller can buy insurance. It's because only the seller has any liability.

#22 KerryR

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Posted 12 April 2013 - 02:43 PM

As John suggests, it doesn't seem fair that you would get stuck with a loss-- this wasn't your fault by any stretch, yet you're the one who's positioned lose out. You should consider getting your money back from the seller and let the seller deal with the issue-- it's more his/her fault than yours or the shippers. At least that's the way it's looking to me. This doesn't fit into the "all sales final" realm, unless you bought it knowing it was broken.

#23 Geo.

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Posted 12 April 2013 - 04:57 PM

Yes, legally the seller carries the liability to get the cargo to the buyer safely unless the parties have expressly agreed otherwise.

See: Primer on Freight Loss and Damage Claims http://networkfob.co...claimprimer.pdf

As the shipper's liability runs to the consignor, he's the one who has the claim for loss and has to prosecute it. He cannot shift his burden to the consignee. Paypal will enforce the consignee's rights if the seller baulks.

Hey, wasn't there someone here last week looking for a corrector?

#24 orion61

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Posted 12 April 2013 - 05:13 PM

If the packaging passes the minimum it should be covered.
If they decide to reop the packages from the back of a Semi instead of lifting it is their error.
There is a thing called expected handeling care of your package.
There will be signs of mis-handeling on the box, even if it landed flat.
Are there pics before shipping? Don't let them give you guff.
You paid for their service and they are responsible for its care while in their hands.
I have battled with shippers about 10 times.. the latest was
just paid off last month, after them trying to decline the
claim!! I wouldn't take it.. A quick letter from my Attorney got their attention.....
Don't give up.. you may be able to buy it back for 10 cents on the dollar for parts... You could sell the Corrector easily.. Not that it would be a premium match.. but may get another system working.

#25 Steven

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Posted 12 April 2013 - 09:39 PM

From the pictures, the secondary back plate is still intake. That means it came off because the collimation screws are not tighten well. Does it have Bob Knobs or the original screws? It sure point to the seller negligence.






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