GTOCP4 Caps


Joe Zeglinski
 

Hi Karen,
 
    Now I see ... in the KIT, those are actually all, in fact, desert “Dust Caps”, but I like to use them to keep any contaminants, wet or dry, off the pins.
Makes sense now. I mistook the rubber cones as leak-plugs, so NOT everyone should be using those, except out west.
Good idea.   :-)
 
    But, maybe add a warning on the instruction sheet, just in case there is a misunderstanding on their application.
My original CP4, and later Mach-2 ones as well,  came with the cone plugs already  installed, so folks east of the great divide, areas  of greater humidity, should be advised to remove them, if installed by a former owner, from out west.
At first, Tony and I thought they were AP pre-installed, for some reason,  as “Case rubber bumpers”.
 
    Glad that is now settled.
 
Joe
 

From: Karen Christen
Sent: Friday, April 23, 2021 10:33 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] GTOCP4 Caps
 

Hi Joe,

 

In addition to Mike’s comments regarding bugs, I would add that some folks use their astro equipment in desert-like settings where dew is not a significant problem, but dust is.  Hence the cone-shaped plugs.  We try to think of everyone in our designs.

 

Karen

AP

 

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Joe Zeglinski
Sent: Thursday, April 22, 2021 10:09 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] GTOCP4 Caps

 

Question to the group.

 

    Can anyone think of a logical  reason to plug “drainage holes”  with those rubber cones?

Do we really want to make sure that any dew or other source of moisture  leaking into the controller, should be kept inside? 

The only thing I can think of is to keep any itsy-bitsy bugs out – but then why drill the two holes into the case, in the first place?

Perhaps that is covered somewhere in the user guide :-)

 

Joe

 

From: M Hambrick

Sent: Thursday, April 22, 2021 8:50 PM

To: main@ap-gto.groups.io

Subject: Re: [ap-gto] GTOCP4 Caps

 

Hi Pete

Those cone shaped plugs are used to plug the drain / vent holes in the bottom of the GTOCP4 housing. Tony (a.k.a. Harley Davidson) made an excellent video a couple years ago about the need to have drain holes in the housing to allow condensate to drain out.

Mike


--
Karen Christen
Astro-Physics


Joe Zeglinski
 

Hi Mike,
 
    If anyone still has the original CP4 released WHITE case – consider drilling the two bottom corner holes, as Tony (a.k.a.  Harley-Davidson) shows in his CP4 video.
 
    My original, like yours,   i.e. the initial release batch’s CP4,  also did NOT have drainage holes, so when the circuit board inside  drowned,   in dew about an inch deep inside - probably from seeping past the exposed Ethernet socket edges.
  I had the original  CP4 board replaced, but unwisely re-installed back into that original-run WHITE case. Who knew what would happen,  again?
    A few outdoor sessions after arrival, the second CP4 board also drowned during a normal night’s use, inside the same CP4 case, ( which is always protected when not in use). That’s when I discovered that the first run CP4 cases were NOT like my old CP3 WHITE case, which DID  have drain holes, and drain plugs were provided in the old days.
 
    The MAIN mistake was replacing the original CP3 on top of the AP-1200 mount, with the new CP4, fully “reposed” there to the dew.
Finally, the now third circuit board is still fine – after AP drilled the two case holes  for me, and I have now silicone-sealed the edges of the panel’s Ethernet socket, for added protection.   The User Guide now strongly advises to NO LONGER use any  old mount’s  upper axis attachment position for a CP4 or later, but rather have it vertically  side-mounted - which is somewhat less prone to dew entry.
    It is those “seemingly trivial oversights”  that gets one in trouble.
 
    I did NOT insert those conical rubber drain plugs from the Kit – why would I ? There never have been any bugs,. not even tiny mites, inside my  old case for nearly a decade, completely exposed in the backyard gardens, and there won’t be, up here in the Ontario wilds. Perhaps the USA southern states have more aggressive bugs seeking a cozy upscale electronics nest. I suppose one could just periodically  pull out the provided rubber stoppers, to drain out any accumulated dew.
 
    Just kidding – tongue in cheek. VERY MUCH pleased with my newest CP4  controller, now high & dry, properly “bolted vertically” on the pier’s sidewall.
 
Joe
 

From: M Hambrick
Sent: Friday, April 23, 2021 9:05 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] GTOCP4 Caps
 
To Joe:

I believe I read or saw somewhere (Maybe Tony's video) that plugging the holes will keep bugs out. This would only be a factor for those who leave their mount set up in a permanent observatory. Interestingly enough, my GTOCP4 (purchased in 2017) has no drain holes in the bottom. I am going to have to go back and watch Tony's video again.

To Ken:

You are correct. The part number that Mouser is sending me is RM15TRD-C(71). It has the correct thread size (M20 X 2). When I entered the other part number (without the "D") in the Mouser search bar it must have brought up the one with the D in it, and I didn't notice. My apologies for any confusion.

Mike


Karen Christen
 

Hi Joe,

 

In addition to Mike’s comments regarding bugs, I would add that some folks use their astro equipment in desert-like settings where dew is not a significant problem, but dust is.  Hence the cone-shaped plugs.  We try to think of everyone in our designs.

 

Karen

AP

 

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Joe Zeglinski
Sent: Thursday, April 22, 2021 10:09 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] GTOCP4 Caps

 

Question to the group.

 

    Can anyone think of a logical  reason to plug “drainage holes”  with those rubber cones?

Do we really want to make sure that any dew or other source of moisture  leaking into the controller, should be kept inside? 

The only thing I can think of is to keep any itsy-bitsy bugs out – but then why drill the two holes into the case, in the first place?

Perhaps that is covered somewhere in the user guide :-)

 

Joe

 

From: M Hambrick

Sent: Thursday, April 22, 2021 8:50 PM

Subject: Re: [ap-gto] GTOCP4 Caps

 

Hi Pete

Those cone shaped plugs are used to plug the drain / vent holes in the bottom of the GTOCP4 housing. Tony (a.k.a. Harley Davidson) made an excellent video a couple years ago about the need to have drain holes in the housing to allow condensate to drain out.

Mike


--
Karen Christen
Astro-Physics


M Hambrick
 

To Joe:

I believe I read or saw somewhere (Maybe Tony's video) that plugging the holes will keep bugs out. This would only be a factor for those who leave their mount set up in a permanent observatory. Interestingly enough, my GTOCP4 (purchased in 2017) has no drain holes in the bottom. I am going to have to go back and watch Tony's video again.

To Ken:

You are correct. The part number that Mouser is sending me is RM15TRD-C(71). It has the correct thread size (M20 X 2). When I entered the other part number (without the "D") in the Mouser search bar it must have brought up the one with the D in it, and I didn't notice. My apologies for any confusion. 

Mike


Ken Sablinsky
 

Thanks Mike, I'd be curious if your model number has a D in it, as I think there's maybe a confusion in model numbers between Mouser and Digi-Key?

Howard's link from yesterday was for "RM15TR-C(71)" from Digi-Key


But on Mouser, at least where I search for it:
RM15TR-C(71) shows a diagram with 19mm x 1 internal thread and obsolete
RM15TRD-C(71) (with a D in the model name) shows 20mm x 2 thread.

In any event, I didn't stop the shipment in time, so I ordered the version "TRD" today.  Looks like I'll have both 19mm and 20mm, to cover all bases!

-Ken


Joe Zeglinski
 

Question to the group.
 
    Can anyone think of a logical  reason to plug “drainage holes”  with those rubber cones?
Do we really want to make sure that any dew or other source of moisture  leaking into the controller, should be kept inside? 
The only thing I can think of is to keep any itsy-bitsy bugs out – but then why drill the two holes into the case, in the first place?
Perhaps that is covered somewhere in the user guide :-)
 
Joe
 

From: M Hambrick
Sent: Thursday, April 22, 2021 8:50 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] GTOCP4 Caps
 
Hi Pete

Those cone shaped plugs are used to plug the drain / vent holes in the bottom of the GTOCP4 housing. Tony (a.k.a. Harley Davidson) made an excellent video a couple years ago about the need to have drain holes in the housing to allow condensate to drain out.

Mike


M Hambrick
 

Hi again Ken

I just received a shipment notice from Mouser for the RM15TR-C(71) caps. I was worried that they might substitute the same one that they recommended for you, but they are sending the ones that I ordered. I will find out when they arrive on Monday April 26. 

FYI - These caps shipped from Mouser Canada. I don't know if they have more than one location, but it is possible that they were only out of stock at the particular location you were trying to buy them from.

I will keep you posted.

Mike


M Hambrick
 

Hi Pete

Those cone shaped plugs are used to plug the drain / vent holes in the bottom of the GTOCP4 housing. Tony (a.k.a. Harley Davidson) made an excellent video a couple years ago about the need to have drain holes in the housing to allow condensate to drain out.

Mike


Pete Mumbower
 

Just going thru my newly arrived 1100GTO boxes and I came across the bag of plastic caps that Karen mentioned above. Here is a picture of all that is included, though I am not sure what the two cone shaped items go to yet. Looks to cover every port on the CP4 that I received.


Joe Zeglinski
 

Hi Mike,
 
    I ordered the plastic caps set for mine. They really should come standard with any CPx controller, and the metal ones offered as a valuable option.
 
    Two things to keep in mind about sourcing the such caps elsewhere.
 
    First, the AP set also includes that ...  tiny plastic plug ... for the CP4/5 USB port (which I don’t use), and it isn’t one of the common PC caps listed in a recent vendor link. The USB and Ethernet socket protection plugs are essential, since these can - (in some perhaps rare cases, like older mount top-side placement), become “tiny water reservoirs”  exposed to dew rolling off an OTA slewing by, potentially  puddling inside the controller. My two unfortunate experiences.
The other  Mil-Spec Amphenol socket ports not only have hermetically sealed leak-proof pin bases inside their sockets, but are very firmly bolted from behind, preventing any panel seepage.
 
    Second, I wonder if the metal caps could become “FROZEN”, (perhaps) difficult to unscrew,  on  exceptionally cold northern winter days.
Guess I would have to either have a portable hair dryer or take the controller indoors, or into the heated vehicle to thaw out the caps.
 
    Tony’s detailed, excellent video  - as  his always are -  about sourcing these metal caps, mentions their underlying “rubber cushions” to provide some push-back, allowing the twist-bayonet cap locks to be snugged-up. But, another benefit of the rubber cushion is to hermetically seal up the exposed tops of the pins, during storage, so they don’t oxidize as easily.
 
    However, I would caution about snipping off the “cap chains” if the scope travels to a dark site. You might lose a cap in the snow or dark ground cover, if they aren’t at least tethered by a shared lanyard to the pier/mount. The black plastic caps are far easier to lose.
If I don’t opt for replacing some of them with the metal caps, I may paint the standard AP black ones with glow-in-the-dark paint. Red plastic “CAPLUGS”, like the AP reducer covers, etc.  would have been somewhat better in that regard, but round ones may not be commonly available in such a wide assortment.
 
Joe Z.
 
 

From: M Hambrick
Sent: Thursday, April 22, 2021 11:58 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] GTOCP4 Caps
 
Hi Linwood

Actually, Astro-Physics offers a set of plastic covers for all of the connectors on the GTOCP4/5 and the mount motors. You will have to call them to order a set. The interest in the metal covers is because they are more durable, and they will stay put, but as a minimum you should get a set of the plastic ones. I think they run about $15.00.

Mike


ap@CaptivePhotons.com
 

> But you won’t need to request them; each mount is shipped with the set. 

 

An even better thing to know, thanks!

 


Karen Christen
 

Hello Linwood,

 

We do sell a full set of plastic covers for all the ports and doohickeys on the CPx control box as Mike mentions below.  But you won’t need to request them; each mount is shipped with the set.  Some folks choose to replace these with metal covers later.  I hope this is helpful.

Karen

AP

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of ap@...
Sent: Thursday, April 22, 2021 11:05 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] GTOCP4 Caps

 

Ah, perfect, when the mount is ready I will ask for one.

 

Mine will be kept inside when not in use, so plastic is likely to work fine.  But when in use it’s a heavy, heavy dew environment so covering unused ports is a goodness.

 

Thanks.

 

 

 

From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of M Hambrick via groups.io
Sent: Thursday, April 22, 2021 11:59 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] GTOCP4 Caps

 

Hi Linwood

Actually, Astro-Physics offers a set of plastic covers for all of the connectors on the GTOCP4/5 and the mount motors. You will have to call them to order a set. The interest in the metal covers is because they are more durable, and they will stay put, but as a minimum you should get a set of the plastic ones. I think they run about $15.00.

Mike


--
Karen Christen
Astro-Physics


Ken Sablinsky
 

Either I'm really confusing myself, or the drawing I found was incorrect.  I found this on the Mauser website showing the "71" version is 19mm x 1, and the 31 version matched that.  Guess I should have measured my actual CP4 instead of relying on the drawings, darn it.  Plus, the 71 version still shows out of stock discontinued - maybe I'm looking at the wrong adapter?
https://www.mouser.com/ProductDetail/Hirose-Connector/RM15TR-C71?qs=%2Fha2pyFadujF6dwDSTFNgVUE%2FRNk7I0u0R6Fk%252BD%252B6mmqK1TJX8uIgQ%3D%3D


M Hambrick
 

Hi Ken

The RM15TR-C(71) caps are the ones that will fit the larger diameter threaded connectors on the GTOCP4 that the Y-cable and Encoder cable attach to. I checked the website and the internal thread specifications for the RM15TR-C(71) and RM15TR-C(31) are different (see below). 

Be VERY careful if you try to screw the RM15TR-C(31) caps onto your GTOCP4 that you do not strip out the threads of the connectors. If they do not thread on very easily, don't try to force them. In fact, based on the drawings below I don't think I would try them at all. I measured the threads on my GTOCP4 and verified that they are M20 X 2 threads.

It is interesting that Mouser told you they are out of stock of the RM15TR-C(71) caps. I ordered three of them yesterday and they don't show to be backordered. I am on the Mouser web site now, and they are showing that they have 26 of the RM15TR-C(71) caps in stock. You can also try searching using the Mouser number 798-RM15TRDC71.

Mike

Here is the RM15TR-C(71) It has M20 X 2 internal threads. This is the correct cap for the connectors on the GTPCP4. 

 

Here is the RM15TR-C(31). It has M19 X 1 internal threads:


Ken Sablinsky
 

Maybe I jumped the gun and ordered too quickly on Mouser yesterday.  They showed the larger cap was out of stock and also said obsolete.  They recommended a different cap, RM15TR-C(31) which seemed to have the same specs as far as I can tell.  Guess I'll find out!


ap@CaptivePhotons.com
 

Ah, perfect, when the mount is ready I will ask for one.

 

Mine will be kept inside when not in use, so plastic is likely to work fine.  But when in use it’s a heavy, heavy dew environment so covering unused ports is a goodness.

 

Thanks.

 

 

 

From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of M Hambrick via groups.io
Sent: Thursday, April 22, 2021 11:59 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] GTOCP4 Caps

 

Hi Linwood

Actually, Astro-Physics offers a set of plastic covers for all of the connectors on the GTOCP4/5 and the mount motors. You will have to call them to order a set. The interest in the metal covers is because they are more durable, and they will stay put, but as a minimum you should get a set of the plastic ones. I think they run about $15.00.

Mike


M Hambrick
 

Hi Linwood

Actually, Astro-Physics offers a set of plastic covers for all of the connectors on the GTOCP4/5 and the mount motors. You will have to call them to order a set. The interest in the metal covers is because they are more durable, and they will stay put, but as a minimum you should get a set of the plastic ones. I think they run about $15.00.

Mike


Seb@stro
 

Hello Howard,

Here are links to the Hirose covers. 
I suppose the two small ones would also fit the CP5 (keypad and power), right ?

What model would you recommend for the RA and DEC threaded connectors as well as those one the Mach2's back panel ?

Sébastien


ap@CaptivePhotons.com
 

> I expect that Astro-Physics' master machinist could easily fabricate whatever caps we

> might ever want, and I would happily pay for them.

As someone waiting for a mount, I’d love if I could just add a package of “covers for every opening” covers to the order, even if they are resold at a markup, it would be very convenient.

 

Linwood

 


M Hambrick
 


What a coincidence ! I also ordered some of the caps from Mouser yesterday. They must think there is a run on the Hirose connectors. I checked the Digi-Key web site that Howard provided the link to, and it said that there was zero stock of the RM15TR-C(71), and also that they were obsolete. I checked Mouser again and they had both types of caps in stock, so I ordered several of each. The last time I checked the Mouser site, they were also out of the RM15 caps, but were expecting a shipment in June. The shipment must have come in early.

Unless someone knows of another manufacturer of these caps besides Hirose, it would be a good idea to grab some up from Mouser while they still have some in stock.

I would still like to find some caps to thread onto the RA and Declination gearbox motors on the mount. I have not had much luck finding anything.
 
I expect that Astro-Physics' master machinist could easily fabricate whatever caps we might ever want, and I would happily pay for them.

Mike