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Tublug question

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#1 Ihtegla Sar

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Posted 18 August 2019 - 09:11 PM

So I just got a new Tublug and the inside is a little loose and was a little crooked. I pushed on it gently with my fingers and it seems to have straightened out but it is just held inside by an O ring and slides around a bit with light pressure from my fingers.

I would gave thought the inside part of the Tublug (the part with the built in Barlow and the 45 degree faceplate) would have been more securely attached to the inside of the barrel.

Is that normal or is there something wrong with my Tublug?

#2 Redbetter

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Posted 18 August 2019 - 11:41 PM

Mine was made a couple of years ago, before Howie Glatter died.  The o-ring (or was it two?) holds it reasonably tightly and it doesn't move that much.  However, after enough insertions of the 2" laser I have had to push the insert back up inside somewhat.  This has only happened a few times despite being used for 60+ sessions per year for several years.  I noticed this when the insert had slid down more than normal and seemed a little looser.  Some of the frequency of this depends on how fast the laser is inserted into the Tublug. 

 

It is possible that the tolerances or o-rings have changed slightly while porting the product line, but I have no way of telling. 

 

My understanding is that the Barlow lens assembly and insert don't have to be perfectly aligned for it to still function effectively, which is why the Barlow method is effective for aligning the primary.  The target face/hole should also not be moving so much that it would result in more than a minor collimation offset



#3 Kunama

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Posted 18 August 2019 - 11:48 PM

I bought one from Howie and another from Starlight Instruments, the Blug in both is very tightly held.


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#4 philinbris

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Posted 26 October 2020 - 09:21 PM

I know this thread is a bit old now, but it is applicable.

My 1.25" TuBlug has just arrived and I was expecting it to have a tiny Barlow in the hole, but to my surprise there is nothing but a hole. I can push a soft piece of plastic right through the hole.

When I put my cheap Laser collimator on it there is zero diffusion and the only way I can make it all work as I expected is to put my own Barlow on my laser then place that lot into the TuBlug then I see a bit of the shadow of the doughnut from the primary. Problem is may Barlow does not fit squarely in the TuBlug as the TuBlug does not accommodate too much length and the Barlow with the lens is a little long.

What am I missing? The TuBlug is simply not usable with just a cheap laser.

 

Also for a fairly pricey device ($260 Australian) I was surprised the small screw to secure the laser was made of plastic and its a sloppy fit.I would have thought they would have supplied a soft tipped metal screw like the guider rings use and a small collar to give the thread some meat.

I got better results using a 2x Barlow on my cheap laser collimator.

 

Any advice, insight, help is appreciated.

Cheers



#5 Ihtegla Sar

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Posted 26 October 2020 - 09:48 PM

I know this thread is a bit old now, but it is applicable.
My 1.25" TuBlug has just arrived and I was expecting it to have a tiny Barlow in the hole, but to my surprise there is nothing but a hole. I can push a soft piece of plastic right through the hole.
When I put my cheap Laser collimator on it there is zero diffusion and the only way I can make it all work as I expected is to put my own Barlow on my laser then place that lot into the TuBlug then I see a bit of the shadow of the doughnut from the primary. Problem is may Barlow does not fit squarely in the TuBlug as the TuBlug does not accommodate too much length and the Barlow with the lens is a little long.
What am I missing? The TuBlug is simply not usable with just a cheap laser.

Also for a fairly pricey device ($260 Australian) I was surprised the small screw to secure the laser was made of plastic and its a sloppy fit.I would have thought they would have supplied a soft tipped metal screw like the guider rings use and a small collar to give the thread some meat.
I got better results using a 2x Barlow on my cheap laser collimator.

Any advice, insight, help is appreciated.
Cheers

The nylon screws are normal for the Tublug. Mine has them and they hold my Howie Glatter laser well without marring it. You could probably match the threads with steel screws if you want a more secure fit on an inexpensive laser. The Glatter laser fits so snugly that you almost don't need the screws.

lf there is no Barlow lens in your Tublug that's a serious defect and you should be looking for a return or exchange. There is supposed to be a very small Barlow lens inside the hole. Mine has one. You can see the lens pretty easily by looking at it under a bright light, since it reflects the light. It's not a coated optic since it is just for collimating. So it is easy to see reflections in it despite how tiny it is buried in that tiny hole. If yours is missing the lens, then it's time to contact your vendor.

Edited by Ihtegla Sar, 26 October 2020 - 11:12 PM.

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#6 philinbris

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Posted 26 October 2020 - 11:17 PM

Thanks Steve, that's what I suspected.

I also expected by looking through it text on a book would be messed up. I can see the text exactly the same as I can without looking through it.

I have contacted the supplier, and he is looking into it.

At the end of the day the screw is not a big thing and I do understand its to protect the device inserted. Just thought they would have a bit more thread to secure things better.

Cheers



#7 philinbris

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Posted 27 October 2020 - 05:06 AM

The TuBlug is being returned for replacement. It must be a manufacturing issue.


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#8 Jon Isaacs

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Posted 27 October 2020 - 10:51 AM

Mine was made a couple of years ago, before Howie Glatter died.  The o-ring (or was it two?) holds it reasonably tightly and it doesn't move that much.  However, after enough insertions of the 2" laser I have had to push the insert back up inside somewhat.  This has only happened a few times despite being used for 60+ sessions per year for several years.  I noticed this when the insert had slid down more than normal and seemed a little looser.  Some of the frequency of this depends on how fast the laser is inserted into the Tublug. 

 

It is possible that the tolerances or o-rings have changed slightly while porting the product line, but I have no way of telling. 

 

My understanding is that the Barlow lens assembly and insert don't have to be perfectly aligned for it to still function effectively, which is why the Barlow method is effective for aligning the primary.  The target face/hole should also not be moving so much that it would result in more than a minor collimation offset

 

Mine has two screws. I removed the bottom screw as my 2 inch HG Collimator is a perfect slip fit and it builds up pressure unless the bottom screw is removed to relieve it.

 

Jon



#9 Dave McCrary

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Posted 27 October 2020 - 11:05 AM

I bought the 1.25" and I had a Farpoint 1.25" laser and there was so much slop that it was unusable. The tublug was 1.25 and the laser was 1.246. I sent the tublug back.

 

Dave



#10 Jon Isaacs

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Posted 28 October 2020 - 05:45 AM

I bought the 1.25" and I had a Farpoint 1.25" laser and there was so much slop that it was unusable. The tublug was 1.25 and the laser was 1.246. I sent the tublug back.

 

Dave

 

Dave:

 

The slop shouldn't matter.  What was it that made it unusable?  

 

The TuBlug needs to be 1.250+ because that's the spec on a 1.25 inch eyepiece and Howie Glatter collimators will be 1.249".

 

Jon



#11 Pinbout

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Posted 28 October 2020 - 07:45 AM

 

The slop shouldn't matter.

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#12 Dave McCrary

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Posted 28 October 2020 - 10:46 AM

Well it sure did on mine. The "doughnut" on mine was all over the place. I sent it back assuming the Glatter Laser was a better fit. I got the Cheshire collimator with the laser and that works fine for me.

 

Dave


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#13 Jon Isaacs

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Posted 28 October 2020 - 02:38 PM

Well it sure did on mine. The "doughnut" on mine was all over the place. I sent it back assuming the Glatter Laser was a better fit. I got the Cheshire collimator with the laser and that works fine for me.

 

Dave

 

Something wasn't right. The beauty of the Barlowed laser is that the laser collimation doesn't matter. You can wiggle the laser and the shadow doesn't  move.

 

Jon


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