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kruscica
05-11-2005, 07:00 AM
Hi.

Having read and listened to discussion on various scopes, eyepieces, finderscopes, etc. and having known what I was after for the best part of the year, I propelled myself to purchase a 10in dob from Bintel last thursday, so that it would be there friday ready for my to use my days off work to learn to use it.
Friday came and went, then Monday, Tuesday. You get the drill. I emailed the sypplier to see if they'd held the scope to make it super-perfect (also since I asked them to drill holes / setup some accessories they didn't have in stock at the time). On Thursday I received a call from TNT - "what's your address, our driver can't find it". Now this was the first I'd heard from them - 5 days of driving around? - use the Melways or a phone directory, maybe? Anway, the truck comes around noon. Wow, it's so light and in one box too! Maybe it's not quite the monster I'd been worried about. Hang on, box one of two! I called the truckers - oh yeah, it must have been separated. We'll check and get back to you. :mad2: Bintel, to their credit, were concerned and mystfied when I let them know.
Today I received a call that my box was coming. :)
Yay!

When I saw the box I thought, is that it! It looked wrong somehow - too wide and too shallow. Of course when I opened it there were a couple of flat pieces and round ones, bags and boxes of screws and bolts and doohickeys.

After a while, I put out a drop sheet on the back veranda, placed the round bits together and the flat ones and stared at the pieces and the fastenings, working out what went where. I started to cross off material received, but take with a grain of salt - it contains material list for all their scopes and not everything is there - you wouldn't really need large and small allen wrench, 1/4 and 5/8 in washers for example.

I started with point 1 of the (about) 5 page manual. The feet were unmistakeable and the wood screws were different to the other ones and were the only set of 3 - they went in from the bottom. It took me a small while to work out the bottom plate was the one with only 3 holes (for the feet) and the plastic backing on the overside.

Then I looked at the front and side boards. All of a sudden I could see how they went together. I screwed in the sides to the front board, then these to the bottom board. It required holding the whole lot on an angle close to perpendicular so as to not put too much strain on the loosely connected boards while finding the holes underneath. Then I put the locking bolt and washer through the bases. The 'nylon' doohickey kept falling out, so I had to thread the bolt and washer through the two bases (it doesn't stick out much) and then push the nylon thing through, then put a washer and the nut. When I tried to tighten the nut, then bolt would move with it. It took me a little bit to position the screw driver underneath and move it in a countermotion to the shifter and nut on the top.

I added the carrying handle. The instruction said to insert the screws in through the capture nuts, then tighten with a screwdriver. What is a capture nut? I realized the nice looking recess for the handle was actually the metallic capture nut and that screw was hanging in the middle of a hole. There was nothing to use a screwdriver on, though, just an allen key for the front. I had put the front on as-about it. :o If I reversed the front board and screwed the screw through the handle it was anchor itself at the back as well. I thought about it. If I did this I would throw away 3 hours of work (much of the time looking for a better diagram on the net, printing the Orion manual, looking for a better screwdriver, lighting, pen, etc.) Then I thought about carrying the scope with the handle as it was. There was nothing for it but to unscrew the locking bolt, unscrew the front and side boards from the bottom and each other. Then I thought, the side boards are back-to-front as well - there were two tiny holes on one that would have to be for the eyepiece rack. However, there were also two large recessed holes that did not reach the other side. I later came to the conclusion they are related to the OTA and springs.

I was a lot quicker reattaching the boards to each other and to the bottom the second time around - about an hour if I include putting the bases together and hunting screws and bolts when they fell out. The book may say 15 minutes, and for some it may be like that, but if you don't have a lot of tools in close proximity, experience in assembly and tools (like the names), and work alone, it will take longer, an hour I would say.

Having created the base, I was left with an eyepiece rack. It seemed clear where it went. I was a little uncertain when the book said to thread the screws loosely so that the rack could be removed by sliding out the screwhole (If I understood that section, the rack would have screw holes larged than the screw heads so that you loosen the screws and then slide out the rack) However my screw heads were larger than the hole, so I just screwed them in until there was little movement of the rack. Also I stopped screwing it in just before it would have broken through to the inside.

With the base ready, I have two long screws with a round wheely head (like focus or control knobs), two long black phillips head screws, 3 plastic sleeve thingies that narrow from the middle, two springs that don't seem to have any give or a way of attaching, and two small circles of rope.

I looked at the OTA and there were brass threads in the middle of the round circles where the OTA would sit on the base, that matched the brass threads on the side boards of the base. I am assuming that two screws go on the OTA, two go into the side board, and the springs and string get attached somehow. According to the book the base in finished and you can put the OTA on now, but that it will fall because the springs have not been installed. 3 pages later in the section on 'balancing' it says how great the proprietary spring tension is, but you can't really tell anything from the pictures except they are there. Both screws are too long for the holes unless I screw them in so that they break through to the inside.

I don't want to scare newbies. When I think about it, it isn't that complicated. The book is written in english and is pretty informative - it exists and is not written in mystifying chinglish or some other unintelligible hybrid. The pictures could be better though - the base diagram looked like a photocopy of tracing paper - faint and small, pics could be lighter so we can see holes and screws and springs clearly.

I guess at this stage, I'm still not sure which screws go in which hole - they fit as well as the other in both positions. Also there is the 'nylon' spacers - what are they for? And just how is the spring and loops attached to the screws even if it does stretch to reach?

Also, I looked at the finderscope and the base for it on the OTA. I didn't really see any screws for it unless I undo the base on the OTA and then thread the screws through the bracket on the Finderscope and the base on the OTA.

Clear Skies and good luck noobs who will follow. I hope my tale will be of some small help to someone. And to those who have gone before me, you are welcome to enlighten me. Close in good quality pics of the various parts would be good, and If you think I've put something back-to-front, let me know.

Phil

davidpretorius
05-11-2005, 08:37 AM
wel done, got any shots mate of the parts?

kruscica
05-11-2005, 06:17 PM
no. no shots yet. I have a camera somewhere but don't think I have the cable to connect and upload.

Phil

kruscica
07-11-2005, 05:59 AM
Part II.

After I arose on Saturday, I cruised the web looking for a really good pic of the tension system and found one. On Sunday I was going to put the OTA on the base and hook it up. I was still concerned about having 3 spacers and 4 screws. Then I found the missing 4th spacer, attached to the OTA. I was going to set it up Sunday arvo, but it was windy and hot and I didn't feel comfortable in those conditions. I did work out that according to the pic, my suspicion on Friday was right. The large-round-knobbed screws go on the OTA, with the spacer thin-end next to the OTA. The ordinary black screws go on the base, spacers fat-end to the screw (thin at the base). This allows the springs to fit snugly between the base or OTA and the screw, going on the spacer.

After I got home from work, washed, ate and relaxed, I went outside to work on the scope at 2am. It was cooler and there was almost no wind. I felt comfortable working with an OTA at rest on the curve of the base. When I did this initially, I screwed the screws in and then worked out that to put the springs on you thread it on the screw / spacer of the OTA and then screw in as far as it goes. I also discovered that there was indeed a small space, as there had to be, that allows the rope loop to go on, and that indeed the spring did extend. I had had some concern that it would be difficult to get the rope on the screw, but when I applied downward pressure, the spring moved without too much resistance. I was able to put the rope on the screw / spacer of the base. One side did twist a little, which I attribute to putting the spring possibly facing the wrong way, but I don't see it having any affect.

With this out the way, I gingerly pushed the scope back and forth to see how easy it moved and how it stayed at rest. Then I looked at the finderscope. Now, the standard finder is a straight-thru model, but I ordered the RA one for an extra 20 dollars. As a result, there was already a dovetail? (base or bracket) attached with two screws. And there was also on on the finderscope which had been boxed separately. I put the two brackets together and they were identical, so I am assuming that I had a spare. The instructions referred to installing the bracket with two screws and I took that to have been done, so I unscrewed a small thumbscrew on each bracket, removed the one from the finderscope and slid it UP the bracket on the OTA. I had expected to slide down, with gravity, but it only moves up, and then you tighten the thumbscrew to secure it in place. I consider it leaves the tiny but possible chance of it falling, gravity and all, but that is the manufacture.

Having secure the finderscope, I took out the cover of the eyepiece focuser? and saw a big hole, where you put the eyepiece in fully. At least that is what I did. I took out the 9mm GSO Plossl and put in fully into the hole, which I take to be a 1.25in focuser. There is one screw on this part, which is the set screw I believe - ie. you loosen it, put your eyepiece in, then screw it a little to secure the eyepiece. There is another ring, with 2 screws. I believe this is the actual focuser, a 2in girth. I did not play with this. Then I looked through the eyepiece. I hadn't dilated, the scope probably needs collimation, and there were clouds (at least I couldn't see any stars naked-eye where usually I see something. I could tell that there was a change - I could see the starless sky, which is a start. If only I could have started with the skies I'd been having earlier in the week while waiting for the scope :)

Any how, the scope is pretty much assembled now, so I can start looking through it. I just need to begin the black art of collimation ;), and work out how to attach the Telrad (which most people seem to put between the finder and focuser) so that it can be moved to best position for me, and then put the batteryholder somewhere. Or at least that's the feeling I got when I looked at the dew shield, a batter holder, and the telrad itself, packet separately. Then it's AN, shower cap and knobs and odds time.

All in all, after a shaky start, it's worked out ok. For the newbies, it's not that difficult, though there may be stumbling blocks, it's all a learning experience.

One question I do have for the veterans, and that is, about the fans. I haven't looked at the underside of the OTA, where the mirrors are, but I did not notice a fan or pieces to power it (unless, as I have just realized, the battery holder I thought was for the telrad may be for the fan). How did it come for you? It was my understanding that provision of a fan and Crayford 2in focuser were longstanding elements of the Premium packages.

Also, I just remembered. I was feeling the tube and I noticed some indentations in the middle of the scope toward the eyepiece side. Not very sharp, but still about 1-2mm in and 5 wide. It seems a little thin. Also, on the other side it seems to not be perfectly round but slightly teardrop ie. sharper. Should I be at all concerned about this. It may be normal wear and tear from transport and lying down in the box, as I wasn't sure which side was the top (and if I put it upside down the mirror would / could fall out), and also thought wind might knock it until it was attached to the base. Thanks.

So Good Night and good luck to all

Phil

slice of heaven
07-11-2005, 06:14 AM
The fan should be premounted on the underside of the primary mirror and the battery pack should be an 8 AA holder. The Telrad battery pack should be inside the Telrad and holds 2 AAs.

iceman
07-11-2005, 06:26 AM
I wouldn't be concerned about small indents in the OTA.. you should see my OTA.. surface rust is setting in :(

But it doesn't affect the views at all. It's the mirrors and collimation that is all you care about with the tube.

kruscica
08-11-2005, 12:08 AM
Thanks guys.

It didn't occur to me until I was writing, that the battery case could be for the fan. And I am relieved to hear that the shape of the tube wasn't likely to be a problem. I thought so, because when I see truss scopes I was initially floored by the idea of all that open space letting light in, whether with a shroud or not, or even that stringscope idea someone made. But I thought I'd check.

Tonight should be a good chance to see Mars. I made it out as I came home, to the north /-west. Apparently the moon is out too, but it is too low on the horizon to see (I mean Starry Night Pro has it at about 20 alt, but I didn't notice it to the southwest.) Scattered cloud and moisture in the air in Melbourne. Should be interesting.

Phil

RAJAH235
08-11-2005, 01:05 AM
Phil, you've done a good job of assembly. One thing I would recommend tho., & that is to reverse the finder base plate 180 degrees, so, as you mentioned, the finder will not slide off. (downwards). I think you'll find it has a 'moulded stopper' @ one end. From the couple of t'scopes that I've seen, most come 'wrongly' mounted. imho.
As Mike says, don't worry too much about the dings.
Collimation is easy, really it is...... http://skyandtelescope.com/printable/howto/scopes/article_790.asp
http://www.andysshotglass.com/Collimating.html
HTH. :D L.

kruscica
08-11-2005, 05:04 AM
Yep. Rajah, that's right. It's at the top end. :) So it IS wrong.

P.

hogly52
08-11-2005, 07:46 AM
Mmmmm :o , mine came that way too, had better reverse it. You'd think years of engineering training and practise might have caused me to wonder, "what if that screw came loose ........, where would the finderscope end up?" Too much faith in the manufacturer and supplier! :lol:

bono
09-11-2005, 04:16 PM
I'm looking at purchasing an 8" DOB. Does Andrews or Bintel do pre-setup before sending out the telescopes?

I don't mind doing the trial/error approach and maybe learn a few things, but the last thing I want is to set the scope up incorrectly.:scared:

Jono

Eardrum73
09-11-2005, 04:30 PM
bono,


Bintel do collimate the scope themselves before shipping it out, but you will still have to asseamble the base. it will be too flimsy to send out otherwise.

Thats not to say that Andews scopes are not collimated. Most scopes should be collimated when they are released from the factory. But Bintel do an extra checkup.

rmcpb
10-11-2005, 08:42 AM
I wouldn't be too worried about the pre-setup as scopes need to be regularly checked for collimation anyway. Make sure you get a Cheshire eyepiece when you order your scope so you can collimate it easily.

Cheers

ving
10-11-2005, 01:09 PM
hiya Jono, I bought my 8" from andrews. the colimation was ok but not spot on. lets face it tho, even if it was collimated before leaving the shop the shipping might knock it out agian anyhow, and you are going to have to learn colimation anyhow cause it doesnt matter how careful you are its going to need re-doing at some stage :)

davidpretorius
10-11-2005, 01:29 PM
I would almost say don't get the $29 cheshire unless it is for an 8". My cheshire compared to other longer varieties performed very poorly

I got the $29 cheshire, the wire that forms the cross hairs is not taut, and for secondary collimation (you must do this first before the primary mirror), it is not long enough.

i am going to get a longer sight tube / cheshire and maybe a laser.

I would recommend spending a little more in this area. Steve H had a very good one, so I will check where he bought his!

hogly52
10-11-2005, 01:38 PM
Hi Jono, Collimation shouldn't be feared. Once you've got a few tools to help and guide you, had a look over the information and resources available on the net, and on this site, jump in and give it a go. You'll need to learn how to do it anyway, and by taking it step by step, in no time at all you'll wonder what made you hesitant about it. Poor analogies, but if you can work a self-service fuel pump or program a VCR/DVD player, you can collimate your scope. I'm sure there are others nearby who can help get you started, if not the supplier. ;)


Cheers, :drink:
Graeme

RAJAH235
10-11-2005, 07:31 PM
Jono, I think Bintel sell a longer collimation tube.(940mm). I bought mine from them years ago, so check. Works fine in my 10" f4.5. Cost then around $69. :D L.
ps. Not the Combination 1.

togo54
11-11-2005, 05:17 AM
My laser collimator arrived in the mail yesterday. After collimating the laser itself in a homemade v-block I put the collimator in the 1 1/4" eyepiece holder. WoW. The secondary mirror was reflecting the laser dot about 1 1/2" off of center spot on the primary. After centering laser on primary I then had to adjust the primary to bring the laser back to the collimator. Total time involved...about 20 minutes....about 15 minutes of that being collimating the laser. And for the record, the dealer I bought my 10" dob from did no pre-service on my dob. The last hands to touch my scope were hands in Taiwan...)