Its arrived! 300p

[Doug]

That is one big scope, Beautiful I have look though a big scope before and know you are going to have so much fun

Doug

[johninderby]

The 300P is a great scope, you'll get plenty of enjoyment out of it.

I used to have one and found the following helped.

Fit carrying handles to the OTA. Makes it much easier to carry, particularly through doorways.

Get the balance of the OTA right. The OTA should balance in the ALT axis and not move by itself even when the tension handles are loose. Add some weights to the lower end of the OTA. Put a small amount of lithium or Teflon grease on the rollers that the OTA rests on.

When you fitted the primary mirror did you make sure that the seam on the inside of the tube fitted into the notch in the side of the mirror cell? Otherwise the screw holes won't line up properly. Here's a photo of the 300P I used to have that shows the carrying handles.

John

[Theninjagecko]

I didn't check the seem? although the bottom seemed a little out of shape, i had to force it on more or less. Mine is also bottom heavy when i take the cap off the front of the scope.

[arad85]

TBH, I'd hold out for the Skywatcher Nirvanas for a set of eyepieces. They are about as good as you'll get without going into Nagler/Ethos territory (and that is debatable). A 28mm 82 deg FoV Nirvana eyepiece will give you only a slightly smaller FoV to the 38mm 70 deg Panaview, and you get the extra magnification.

FWIW, I don't forsee buying another wide angle low mag eyepiece now I have a 31mm Nagler...

[johninderby]

I didn't check the seem? although the bottom seemed a little out of shape, i had to force it on more or less. Mine is also bottom heavy when i take the cap off the front of the scope.

I had added a new focuser and different finder and it was a bit top heavy but yours might need a more weight on the top, a "dew shield" to help block out stray light perhaps (in this case it would just a light shield).

Here's a photo of a SkyWatcher dob (different size) that illustrates the seam and the notch.

Johh

[Theninjagecko]

So the seam on the tube lines up with the notch on the cell ?

[johninderby]

Yes. I think that there may be two notches on the 12" cell, one on either side, but it doesn't matter which one you use. When you line up the seam and notch the cell should just slide into place.

If you look inside the top end of the scope you should see how the seam fits into the notch in the top tube end ring.

John

[Theninjagecko]

Yes. I think that there may be two notches on the 12" cell, one on either side, but it doesn't matter which one you use. When you line up the seam and notch the cell should just slide into place.

If you look inside the top end of the scope you should see how the seam fits into the notch in the top tube end ring.

John

Should i lay the cell on the floor and fit the tube ontop or lay the tube on its side and insert the cell ?

[Theninjagecko]

hmm, just took the tube off, and no notch on the cell.

[johninderby]

Are there any indentations in the edge of the cell where the seam could fit?

John

[Theninjagecko]

Are there any indentations in the edge of the cell where the seam could fit?

John

i can get the scope to fit into a seam on there, but the holes just don't line up. I'm having trouble with the last 2 now. one hole isn't even visible!

Whoever drilled the holes for this tube need sacking.

[Theninjagecko]

Here are a couple of pics of 2 of the holes.. All the screws are in bar 2. the tube wont budge at all to work the screws in or anything.

1.

2.

[johninderby]

Is it possible to remove all the screws and rotate the cell 180 degrees and see if the holes lineup.

If the holes then do line up perhaps only putting the screws half way in until all the screws are in might help.

John

[Theninjagecko]

the tube wont rotate once in the seam, its too tight, i have to take it off then plant it back down, ive tryed all ways, only 1 hole will line up, thus making all the others miss aligned.

[Theninjagecko]

Should the 3 black plastic bits that hold the mirror down to the cell be lose? the smaller screws on the bottom of the mirror cell are also lose.

[simon84]

Congrats on the scope mate, I see you got some pictures up quicker than I did.

I picked up a fairly cheap 2" Rigel 32mm 70 degree FOV EP and it gives fantastic views. I can frame the Pleiades perfectly with it, it does go a little bit soft around the edge but after my wife has got over the shock of the cost of my 300P I might be allowed to look at Naglers......

With regards to your cell, I had no cutouts on mine either but my holes were pretty good with lining up. Now its all up and running I do feel that some dew prevention of some sorts is needed, my secondary and finder suffered after only a few hours viewing.

Nice that you got the right angled finder, thinking of switching to a telrad myself, read some good things about those.

Well good luck with it and its nice to know that the cloudy skies arn't my fauly anymore.

Cheers,

Simon.

[FLO]

Should the 3 black plastic bits that hold the mirror down to the cell be lose?

(have only just found this thread)

Yes, they are supposed to be slightly loose, they should not be cinched down tight onto the mirror, they have a gap (about the width of a piece of paper) to allow the mirror to expand/contract.

Please bring me up-to-date on the ota/holes/mirror thing. We have sold a lot of these Skyliner 300p Dobs, so far all the mirror cells have fitted to the tube without difficulty

the smaller screws on the bottom of the mirror cell are also lose.

Can you post a picture please.

If at any time you decide your OTA is faulty then please put it back into its original packaging and contact us so we can arrange collection. Please don't modify the telescope or carry out a repair.

HTH

[Theninjagecko]

on the bottom you have the col screws and the lock screws i think? the locking screws are lose, so i tightened them slightly, by lose i mean they would rattle.

i posted 2 pictures of how the holes wont line up. ive managed to get all the screws in bar one now. The problem is you line up one and the rest arnt aligned right. Made it a nightmare to get the ones in Ive got in, but had to screw them in with some force.

It's not such a problem just not looking forward to when i have to clean the mirror.

I had a 8 inch helios dobson before this and didn't have same problem connecting the mirror cell to the ota.

[FLO]

If you have followed John's advice and they still don't line up then we had better have the OTA back. Please repackage the OTA and mirror cell back into their boxes (we don't need the mount) then advise us by PM of a convenient date and location for collection.

Apologies for the inconvenience. You have been very unlucky, other than one that was damaged in transit (dented tube) I don't think we have ever seen a faulty 300p.

[Theninjagecko]

If you have followed John's advice and they still don't line up then we had better have the OTA back. Please repackage the OTA and mirror cell back into their boxes (we don't need the mount) then advise us by PM of a convenient date and location for collection.

Apologies for the inconvenience. You have been very unlucky, other than one that was damaged in transit (dented tube) I don't think we have ever seen a faulty 300p.

The only problem seems to be getting the last screw in. i put the cell on the floor then lower the ota over the celland carefully trying to align the screw holes as im coming down with the ota. I'l make a video to show you. 1 hole isnt a problem steve, im just wondering if it was me not connecting it right.

[FLO]

Take your time and let me know

[Theninjagecko]

Here is a small video as promised.

What is the correct procedure to put the mirror cell back into the OTA?

[John]

Sorry if I've got the "wrong end of the stick" on this but if the cell does not have the notch for the tube seam in it then the tube could deform slightly because of the seam pressing against the notchless rim of the cell - could that slight deformation be why the screw holes don't quite match ? Isay this because I had a similar problem with an 8" dob - but that was because I did not spot the notch in the cell and therefore did not fit the tube seam into it !.

Interestingly the 300P model that was tested by Ade Ashford in Astronomy Now when it 1st came out had a welded (therefore seamless) tube - I can recall Ade being pleasantly suprised by that.

John

[johnh]

Hello Scott, just caught this thread - you've got a great scope there and am glad you saved up for the 300P as SW these days make excellent optics. When you buy a big scope you don't realise how big it really is untill it is standing there in your hallway.

You now have all the NGC available for viewing and I bet you are dying to see M42 and even the horsehead nebula with the right filter.

Clear skies, JohnH.

[bish]

Great scope. Someone kindly let me have a look through is 12" flextube at Kielder. M13 was incredible, as was M57. Would have liked to check out M51 but didn't get a chance. As for dew, I had never experienced it at all on my scope until my first year at Kielder and my secondary mirror got totally dewed up very quickly. Got myself an astrozap and hair dryer for the following year.