FrankenSaxon

[brian nordstrom]

Hi all , as the title suggests here is my ' FrankenSaxon'

I got this standard 102mm f10 black tube Saxon refractor here in the IIS classifieds for a steal and upon using it realised although the optics are first rate , very good actually and the focuser while Ok was the weak link here .

I was going to grab a LP 10-1 focuser from Andrews for $70 like I have on my 90mm f10 Saxon but a GSO Linear that came up here for only $100 so I grabbed it .

Fast forward to yesterday and the focuser arrived and being off a SCT but was not compatible with the 102 ( I knew this before buying )
and it is rotatable so it was easy to machine up an adaptor and this morning so this adaptor was machined up to mount it on the 102mm Refractor OTA .
.
I had to move the finder to the side of the tube , easy as I have a few bases in my junk draw , drill 2 holes and bolt it on .
The adaptor was measured up to replicate the length of the standard R&P focuser so all my eyepieces will reach focus .
The screws are M4 x 14 CS stainless steel that hold the focuser to the adaptor and M4 threads to attach the adaptor to the OTA .

I must have done something right ;) as a quick test with a laser colimator had the red dot dead centre of the lens :thumbsup: .
I like the feel of this focuser , nice and smooth with just the right ' Weight ' and is very well made , typical good GSO quality .

I also made a carry handle for the rings at work the other day .

FrankenSaxon you may wonder why :question: , well the OTA is Saxon ( Synta ) , the 8x50 finder is Celestron , the focuser is GSO , the mount is a sweet Vixen SP , the SloMo controls Mizar and tripod is a Meade HD field model , a bitsa for sure but it all works well as a unit and has become the scope of choice for those quick look sessions we all enjoy .

On that I hope you all enjoy my journey with this scope as much as I have and I had forgotten how well these 4 inch refractors perform , brilliantly .

Brian. .

[brian nordstrom]

One more photo of the 102 and one of the LP focuser on the 90mm .

Brian.

[Tinderboxsky]

I like it Brian. Definitely enjoyable spending "shed time" making improvements to one's astronomical equipment.

[brian nordstrom]

:thumbsup: Yes Steve I love doing it as well it's much better than rotting your brain watching that carp on TV , a few coldies , good music , my wife is always asking , " What do you do out there all the time ;) " .

"Stuff and things" my darling .

Brian.

[brian nordstrom]

ATM'rs out there ? :thanx: . enjoy as I do .

Help me ! :thumbsup: , I saved this POS off the road side on my Push bike going to work friday ,,, terrible ( but thru it in my back pac and got it home ) that they sell these ... 50mm f9 , plastic city thats broken ,,, another young astronomer lost ! , I can only imagine the dis-:help: apointment from an aspiring young amateur astronomer with one of these .

Brian.

[MortonH]

Beautiful result, Brian!

Will make a world of difference compared to the stock focuser.

[ZeroID]

:thumbsup: Definitely !!

[brian nordstrom]

:thumbsup: Well , the long weekend was great here , 3 perfect nights so I had the frakensaxon out all 3 .
On the second night it was cooler than we have had for what seems like ever and noticed a bit more SA on the out of focus stars :question: I wonder .

I took off the dew shield and grabbed a 3mm allen key and phillips head screwdriver and had a go at a little lens colimation , cant really hurt now , can it ?? .
fast forward 1/4 hour and no amount of adjustments made any difference to the SA that was showing ?? it was worse than last week by a fair margin , ok .:shrug: .

I took the ota into the shed for a better look and putting it on the table and rolling it a bit I heard a faint rattle :D YES ! I know what that is , and mounting the ota on a mount in the shed and putting the lens pointing straight up looking at the retaining ring and YES :D it was loose so a few light taps on the cell to settle it back in place as I snugged it up and then setting the colimation screws back to zero position I was back out and after a few attempts had the lens perfectly aligned and what a difference , almost perfect intra and extra rings showing a 90% improvement of the SA , just a little colour in the centre rings but that all but disappares in focus , just a perfect aeiry dick with the faintest of rings around it .

That beautiful Vixen SP mount is a sweet mount , when alligned south well it keeps the object dead centre for 1/2 an hour or more at over 200x and this makes colimation easy , just a touch of a direction button to re-centralize after a tweek , very nice .

The CA was also a lot better in focus , none seen on 3-4th mag stars , just a little on 2nd mag and even Rigel at over 1st was pretty clean with it's companion very easily seen , very good .

Jupiter and saturn were awesome at 200-250x , Mars was ok , getting better all the time . The tripezium was so good at 200x I just took it in for a long time until it got a little low in the west .

I knew this was a good achromat but its even better now after a little maintiance and my advise , if you suspect there is a problem with colimation , even with a doublet refractor don't be shy to have a go , it can make a huge difference .

Brian.

[brian nordstrom]

:D Well I forgot to add a photo of the scope waiting for dark . Here it is .

Also a shot of some tree tops about 750 metres away the day after the colimation to show the ( lack of ) CA . As always , my phone held up to a 15mm TV plossl giving 67x , the slight blureing was due to a strong wind blowing .

Brian.

[Prickly]

Hi Brian

An awesome setup. The SP is a great match for the Meade field tripod by the looks of things. As I have a SP mount do you mind my asking whether you needed to make any adapter to fit the SP mount to the tripod.


Also have you tried it with the c9.25. The c9.25 might be a bit heavy perhaps but the beefed up tripod may help


Cheers
David

[brian nordstrom]

:thumbsup: Hi David , no worries mate .

To fit the SP to the Meade tripod top all I did was machine up a 100mm dia alloy block with a 60mm hole to fit the bottom of the mount and screwed it down in 3 places from underneath with 3 off M6 x 25 S/S bolts . For the azimuth pin I drilled and tapped a M8 x 40 S/S bolt with it's head cut off and screwed it in with a lock nut underneath , its good and solid as the M10 threaded rod that holds the spacer does all the work holding the mount to the tripod .
This is super solid holding the 102 with hardly any vibrations when focusing and a good smack on the tube while viewing at 100x plus dampens in about 1-2 seconds , very nice .

I have not tried the C9.25 as it's got a Losmandy dovetail fitted but I dont recon it would be a problem ,, in a pinch ;) , this set up holds my iStar 127mm f8 refractor ok ( when I use my 2nd set of rings fitted with a Vixen dovetail , and its heavy but I use it and the C9.25 on the SOLID !!:eyepop: Celestron CI700 mount .
Those tripod legs are 3 inches in diameter. .

See photo .

Brian.

[Prickly]

Thanks Brian

That celestron mount looks a fine bit of kit. I am soon to get a c9.25 and I must say that looks an excellent match for the CI700. I suspect the c9.25 may be confined to my Eq6 rather than the Super Polaris. I could be very tempted at some point to upgrade from the Eq6 although it has served me well and does the job. The CI700 looks beautifully machined and looks a lot like the G11.

Thanks for the details on the adapter. I have an old c102 and they are nice scopes and very portable.

Cheers
David

[brian nordstrom]

:thanx: David , yes these were mostly built by Losmanday for Celestron so very solid and tracks beautifully , they used to put C14's on these as good as they are that's about Max for a mount of this size , 3.8 metres of focal length will tax the best mount under 10k , usable yes ,,, just but a C11 would be perfect as it is under my C9.25.

Here is my iStar 127mm f8 on it , note the position of the counterweight ;) , plenty more weight able to be put on it .

Your EQ6 would hold a C9.35 with ease as I used an HEQ5 for years , no worries and yes these 102mm f10 achromat's on a Vixen's SP mount is a great setup , so easy and fast to set up and use ..

Brian.