Vixen Porta

[Alan64]

I'm sitting here wondering as to how many reading might have, or once had, this smaller of alt-azimuth mounts...

It exists currently as the "Porta II", for what that's worth. However, this one that I managed to stumble upon, and noticeably with other interested parties doing just that, exhibiting uncomfortable interest, is older, a good bit older given its rather unusual colouring.  It's not as dated as this...

My guess is that it was born sometime during the 1980s, if not the late '70s.  I can't find any history of this mount online, nothing.  

Truth be told, I bought it twice.  After the first sale, and as an afterthought, I sent the seller this image, inquiring after the tripod's hub, of the same colour, but with aluminium legs with white trim...

It turned out that no, the hub was not included, so I asked the seller to cancel the order, which they did.  

But there it was the next day, re-listed by the seller, and drawing me.  Then, a new Svbony 225 alt-az head doesn't come with a hub, either..

https://www.amazon.co.uk/Alt-Azimuth-Adjustable-Altazimuth-Adjustment-Accessories/dp/B0CMD5YBSD/ref=sr_1_3?crid=6Q9EXJGHXLBL&dib=eyJ2IjoiMSJ9.MhzWJ9pQgd5wzhW-ALnz3OWHIrnQWXzgPk-uO0HsXoFQ7mpQ7MrxgH_epSfBz7zkeut3zSbX9r-j7M_HH4SIQVJAdNugCUlXDnKXeH4uiP66PuJ-LU6cYJ5kn7vDGc7LIS5eueq9mHRzW9CRmZOauZdUSlWEKF8ooIxpXVsQM4JcSL054yeVTSB01fw2VYOd1BKLZ9EwgbviP43amQ13-P9MGE5QzXWOYH8OPfosQXE.xkro41tL3ld5Rluyq6DGECprT1Cabe7yCjVtbUq8lDI&dib_tag=se&keywords=svbony+sv225&qid=1719720839&sprefix=svbony+sv225%2Caps%2C187&sr=8-3

So I purchased the old Porta head a second, and final time.  

The seller simply wanted a flat $100 for it.  It's now on its way to me from New Jersey.     

Ideally, the mount should never have been parted, but I'm not complaining.  

I can't wait to replace the axes's washers.

[JeremyS]

I have a Vixen Porta and tripod, original version, but white. I use it with my Lunt 50mm Ha scope. Works fine, useful slo-mos, but I wouldn’t want to put anything much larger on it.

I also have a Mini-Porta somewhere. Now that’s a pretty poor mount!

[John]

I had one of the first generation Porta mounts a long time back (probably around 2008). It was quite good with my Vixen ED102SS F/6.5. I didn't try anything else on it though (just had one scope back then 🙄)

Edited June 30 by John

[PeterStudz]

5 hours ago, JeremyS said:

I also have a Mini-Porta somewhere. Now that’s a pretty poor mount!

Interesting... I had my eye out for one of these (secondhand) for a small grab-and-go/travel setup. But they aren’t readily available in the UK, so I eventually gave up waiting. Maybe just as well!

And nice to see @Alan64 back. I might have missed some recent posts so could be mistaken, but Alan has made some superb threads on this site in the past. I just like to take the opportunity to say thanks. Many were informative, useful to me and also great reads.

[almcl]

3 hours ago, PeterStudz said:

And nice to see @Alan64 back.

Alan has made some superb threads on this site in the past. I just like to take the opportunity to say thanks. Many were informative, useful to me and also great reads.

+1👍

[Naughty Neal]

Not having the same kudos as the VP one can get a  clone version Sparta  from AliExpress , mine was approx.£45.

[Alan64]

My thanks to all who have replied.

It finally arrived...

 

The L-shaped arm of the mount is not in one piece, but in two pieces.  We'll have to take that apart someday...

There are two neodymium magnets, which hold the two hex-keys in place...

I think I know as to what the off-colour is due: tobacco.  I had already ordered and received this...

I want to paint it a metallic red, somewhat darker, like a dying star about to nova.  But the Sun will fade the paint, turning it orange most likely.  But then, there are red glitter paints, which may be more resistant, and requiring several clear coats, like a fine automobile...

The base of the head...

I will need a 1/4"-20 to 3/8"(or 10mm-1.5) adaptor if I want to attach it to my astro-tripods.  I've seen an adaptor from Singapore, but I'd rather make my own, with brass or stainless(if I might find them) inserts.  The disc will be taken from this...

[Stephenstargazer]

I had a Vixen Porta c2007, but thought the tripod was the weak link and made an aluminium adaptor (M10) to use it with the excellent HAL 130 tripod. Those are both sold now but the adaptor remains.........somewhere.

Tobacco? Now that is what I call a heavy smoker!

 

[Alan64]

28 minutes ago, Stephenstargazer said:

I had a Vixen Porta c2007, but thought the tripod was the weak link and made an aluminium adaptor (M10) to use it with the excellent HAL 130 tripod. Those are both sold now but the adaptor remains.........somewhere.

Tobacco? Now that is what I call a heavy smoker!

I can't say as an absolute, but it certainly does appear to be tobacco staining, possibly by more than one smoker in the household somewhere in New Jersey.  It was an estate sale, and we all know what that might indicate.  But then, there is some evidence that the mount had been semi-stored outdoors...

That black-oxide set-screw had been facing skyward for years, but it wasn't rusted too badly...

Hence, did the Sun cause the discolouration?  

[plyscope]

These Porta mounts are very handy for smaller scopes. I bought mine way back in 2006 and wrote this review.

https://www.iceinspace.com.au/44-353-0-0-1-0.html

I still use it mostly with a TV60. I tried heavier tripods but then the lightweight convenience is compromised. For the TV60 the standard tripod is fine.

[PeterStudz]

I do wonder why it has yellowed like that. Many white paints will yellow given enough time. But some paint types suffer more than others. And some environments make it happen quicker. 

With oil based enamel paint (especially older enamel paints) it can actually be down to being kept OUT of sunlight. and not in sunlight. As mentioned here…

https://www.dulux.com.au/applicator/technical-advice/performance/yellowing-of-enamels/

But that can’t be what had happened here, as you can clearly see that parts of the mount that were covered (ie out of sunlight), like the Allen key compartment & where covered by the dovetail, are still white. 

So for me best bet is too much strong sunlight or tabacco smoke.  Now, it’s a long time since I lived in old rented student accommodation (where there was or had been a heavy smoker), but from memory it didn’t take a huge amount of smoking to stain light coloured items.

And since the mount didn’t come with a tripod or head, maybe it had been mounted/fixed to something solid outside. In which case it could have spent much time out in the sun. Why would the head/tripod be removed? It’s my understanding that the tripod for this doesn’t fit anything else. 

Anyway, enough rambling!

[Alan64]

It was upon the removal of the clamp when I began to strongly suspect tobacco...

There's a rather dirty dust-bunny nestled within the large hole at left of centre.

The faces of the D-shaped ends of the worm-shafts; note that only one of the altitudinal faces was marred by a set-screw, at lower-left...

The rubber cover for the hex-key compartment is in remarkably good shape.  It is dirty on the outer, skyward side.  After cleaning, I will treat it with Armor All, and a bottle I've had for many years...

Based on this statement, or disclaimer, within the buy-it-now listing...

...I was prompted to enquire as to any and all accessories that might've been laying round.  Anything at all that might've gone with the mount.

When I opened the box, these had been included by the seller...

Ah, there's the offending screw-type cable, at right.  Vixen provides, there at left, friction-fit controls, which are fine if the worm-shafts twist most easily.  If only they would, for of that, the axes and worm-shafts do not turn so easily, not on this head, not easily at all, and I know why. 

"At first glance we thought the stand was so well finished and assembled, rigid and free of slop that we thought it was made in Japan. But this mount is designed by Vixen Co., Ltd. in Japan, then manufactured in China with the cooperation of Vixen engineers." - Company Seven

The damping of the axes with the equivalent to molasses, or tar even, and throwing in these two set-screws...

...just isn't going to get it.

 

 

[Alan64]

That threaded hole is 25mm in depth, from the outside surface to the "pipe" inside.  From that...

The two axial set-screws are now in the bowels of history, or is that the annals thereof?  These will replace them, from Amazon...

I got these as well, but from AliExpress.  They are 5mm longer than the others, and so to clear the slow-motion control-modules just above...

But we can't have an iron-based set-screw bearing against the aluminium "pipes".  The original set-screws are 8mm in diameter.  A buffer between the stainless-steel tips of the levers or knobs on order and the "pipes" is necessary.  The shafts have a solid core 6mm in width, hence, also via AliExpress...

10mm long slugs will be sawn from the rod.  I would've used brass, but I've graduated to the bronze, for these inserts.  Bronze will bite better when the axes are clamped or locked, resulting in less slippage, if any at all.  That's the theory anyway.

Edited July 7 by Alan64

[Mr Spock]

I have one stuffed in a cupboard where it's been for years. I put an 80ED on it and it was like jelly. Plus one of the slow motion controls broke. I'm not sure why I haven't binned it.

[Alan64]

11 minutes ago, Mr Spock said:

I have one stuffed in a cupboard where it's been for years. I put an 80ED on it and it was like jelly. Plus one of the slow motion controls broke. I'm not sure why I haven't binned it.

That's somewhat startling, as I've found the head to be built like a tank.  Was there that much slop in the axes?

[Alan64]

The saddle was removed first, with its knob and thumbscrew put away in a bag.  The saddle will be going into a either a quart or gallon freezer-bag, and after it's coated with the formic-acid based paint remover. 

The disassembly of the head begins; the azimuthal-axis is removed from the two-piece L-shaped arm...

The front and back of the azimuthal-axis...

Note what is used instead of a nut on the central bolt; a pin of tool-steel, and for a flush surface.  However, that may not need to be removed to disassemble the axis.  But then, what will I encounter upon removing the medallion of the altitudinal axis?

I haven't done that yet...

We have a chain of stores here in the First Colony called "Dollar Tree".  Up until several years ago, the vast majority of items actually sold for $1.  Everything is now $1.25.  That's how much I paid for that sponge-holder, quite a few actually, almost ten.  I prefer to wash dishes by hand.  Others in the household use the dishwasher, that I installed, and repaired recently.  

From that sponge-holder, there are two rather large suction-cups.  The idea is to use a blow-dryer to heat up the area round and about the medallion, attach the suction-cup, pull it off, and all in one piece. 

Never pry it up, lest...

That individual pried up the epoxy-based(or other) decorative portion, instead of the white, metal plate underneath, but the latter would require digging or drilling out a place to wedge in a small screwdriver.  

I'm going to use the heat-and-suction method, first.  But I'm not going to use a blow-dryer...

After heating it up for a while, I'll test the medallion's surface for stickiness, and before placing the suction-cup onto it.  I hope it works.  I'm in an unknown territory with this.

That's the drying-rack that came with the previous dryer, a Whirlpool.  It also fits this relatively new one.  What a stroke of luck, as I like to use the rack on occasion...

[Alan64]

I heated that part of the head, and to where one could not hold on to it for any real length of time, but to no avail.  Fail.  However, I am not daunted in the least.  

I will drill, and dig, below the metal plate, then heat it again in the dryer, and try to pry it off in one piece.

[Roy Challen]

On 07/07/2024 at 06:23, Mr Spock said:

I have one stuffed in a cupboard where it's been for years. I put an 80ED on it and it was like jelly. Plus one of the slow motion controls broke. I'm not sure why I haven't binned it.

If you're going to bin it, I'll take it off your hands! If I can't get it working, I promise to make sure it goes in the recycling 😜

[Alan64]

10 hours ago, Roy Challen said:

If you're going to bin it, I'll take it off your hands! If I can't get it working, I promise to make sure it goes in the recycling 😜

I believe that once I unlock all of the secrets of this one, that it will help others with their own; even purchasers of brand-new units.

[Alan64]

I drilled a hole,

I know not where,

"Was it crooked or straight?"

I haven't a care.

You may see where I had started, but then skittered upward and drilled there instead.

I had used a 1/16" drill-bit, perhaps a bit too large, in hindsight.  The hole is 1/8" in height, and as you can see it did not break through the top.  I then removed and reversed the bit, inserted it into the hole it had made previously, and used it as a pry-bar, to pry the medallion up and off...  

Afterwards I had thought about a smaller hole instead, perhaps 1mm, and with the use of a curved heavy-duty quilting-needle or other to pry it up.  I would cut or snip off the sharp tip of the needle.  Of course, the operation should be done after that area is thoroughly heated.

The entire backside of the medallion was sticky...  

But I thought it was adhesive applied to white paint.  Based on that, I proceeded to soak the reverse with charcoal-lighter fluid, which is a high or highest grade of kerosene.  I then scraped it all off...

It turned out that a circular, two-sided adhesive sheet was used for the medallion's attachment...

[Alan64]

I will be re-attaching the medallion, in future, via three small neodymium magnets, and with risers crafted from the various hardwoods that I have on hand...

My decrepit Minolta still has what it takes.

I marked the axes...

I'm chomping at the bit to get inside of those, but it must be done carefully, slowly, and photographed.

It's time to strip this portion of the head, to remove the contaminated powder-coating...

[Alan64]

Firstly, I treated a small area with the green paint-remover; success...

Subsequently, I then slathered down the entire arm with the stuff...

After about five hours, I started seeing results...

Note the squiggly, wavy paint.  It will sit overnight before I inspect it again.  I also added the bar-clamp, and in its own bag...

[dave34]

Cant wait to see the finished item, metallic candy apple would look a treat, great thread.

[Alan64]

It appears that certain areas were unaffected by the onslaught.  I may, or may not, need to re-do those areas.

[Mr Spock]

On 07/07/2024 at 06:23, Mr Spock said:

I have one stuffed in a cupboard where it's been for years.

Dug it out this afternoon. It's actually a mini Porta  I might try the 60mm on it.