Collimator help

[MrRusty]

Hi everyone,

I'm new to the forum so hoping that I'm posting in the right place.

I have a Revelation Collimator which I have used successfully in the past with my newtonian, but the battery in the collimator has run out and I can't for the life of me work out how to replace it.  I've searched all over and can't find any advice or instructions.

One end of the collimator unscrews, but only reveals the top of what I presume is the laser unit.  This appears to be fixed in place.  There are 3 screws on the body, presumably for collimating it.  I don't want to undo these unecessarily, but cannot see any alternative. 

Any advice gratefully received.

thanks in advance

MrRusty

[Ricochet]

Does that little metal cap that has been exposed pull off? It might be that it is supposed to be attached to the part you have already removed. The dull grey tube beneath it contains the batteries. The laser part must be at the end that the beam comes out of, else the batteries would get in the way of the beam. 

[John]

I have one just like that. The 3 grub screws inset into the body press against the laser unit and those are how you collimate the unit. To replace the batteries, you unscrew the silver cap on the end of the laser unit using a thin hex key or similar in the hole drilled through it to give you leverage.

Hope that helps.

 

[MrRusty]

Thanks for the feedback.  The cap unscrews to reveal the batteries.  2 of which have come out with the encouragement of a strong magnet, but there's another (at least 1) which is not coming out.  It'a bit of an awkward design really.

Any final tips on how to remove stuck batteries ?

[Alan64]

31 minutes ago, MrRusty said:

Thanks for the feedback.  The cap unscrews to reveal the batteries.  2 of which have come out with the encouragement of a strong magnet, but there's another (at least 1) which is not coming out.  It'a bit of an awkward design really.

Any final tips on how to remove stuck batteries ?

In that it was inserted, it can be removed, if with persistence.  You don't want to pour oil or other inside to loosen it.  If you don't have a set already...

https://www.amazon.co.uk/Rolson-59136-Probe-Set-Pieces/dp/B001MJ0JOU/ref=pd_lpo_60_t_0/260-8574297-3163865?_encoding=UTF8&pd_rd_i=B001MJ0JOU&pd_rd_r=2e2ab246-55a1-49a2-a8f8-e93e32d541b1&pd_rd_w=jmBct&pd_rd_wg=CwlxB&pf_rd_p=7b8e3b03-1439-4489-abd4-4a138cf4eca6&pf_rd_r=ZRTEMT7CSDB1YZ3462VA&psc=1&refRID=ZRTEMT7CSDB1YZ3462VA    

[Starwatcher2001]

Bluetack on the end of a pencil?

[John]

11 minutes ago, Starwatcher2001 said:

Bluetack on the end of a pencil?

Yes, I think that might do the trick.

[MrRusty]

Thanks for all the tips.  I've been using a very strong magnet without success and bluetack doesn't work either.

I'll try and get some probes as sub dwarf suggested, but I'm beginning to think that I'll have to drill it, then attach a screw to pull it out.

I don't think changing batteries should be this hard !

 

[Ricochet]

On 13/10/2020 at 12:12, MrRusty said:

Thanks for the feedback.  The cap unscrews to reveal the batteries.  2 of which have come out with the encouragement of a strong magnet, but there's another (at least 1) which is not coming out.  It'a bit of an awkward design really.

Any final tips on how to remove stuck batteries ?

The collimation screws for the collimator push against the sides of the battery holder. Someone has tightened them too tightly and now they are digging in and preventing the battery from being able to pass down the tube. You will have to loosen the collimation screws, change the batteries, and then recollimate the collimator. 

[Starwatcher2001]

A previous thread says there's three batteries, so you've just got the one to extract. It also explains how to collimate the laser:

https://stargazerslounge.com/topic/337135-revelation-astro-collimator-battery/

 

[MrRusty]

Genius !

Undoing the colimation screws has indeed freed the 3rd and final battery. 

I'll follow the link to the recollimation instructions and I'm good to go.

Thanks everyone for all your help.

 

 

[Ricochet]

1 hour ago, MrRusty said:

Genius !

No, experience. 🤣

If yours is like mine there is enough strength in the battery holder/laser assembly that it will hold position in the v block without any of the collimation screws touching it. You can then carefully tighten just two of the screws to collimate and then nip up the third one, hopefully without pinching the batteries again.