Fitting Sky-watcher Star travel 102 to EQ6 Mount

[Taff]

Hi' I am looking for some advice please.For the first time tonight i tried fitting my Sky- Watcher Star Travel 102 to my EQ6 mount but could not get the dove tail to fit when turning the two knobs.But i did noticed the two bolts under the dove tail are in the way,can any one help me along what to do.Thanks for reading.Mark

[fozzybear]

photo's might help as a guide even from you phone

[Merlin66]

Yeah,

This happens when the dovetail is too short for the length of the saddle clamp on the mount.....

Some short OTA's don't allow a longer dovetail to be used...

The answer I've found is to replace the socket head screws normally used to connect the tube rings to the dovetail, with M6 x25mm countersunk screws and drill out the base of the dovetail to accept the countersink.

Not to many other solutions........ 

[Taff]

35 minutes ago, fozzybear said:

photo's might help as a guide even from you phone

 

[Merlin66]

The two smaller screws on either side of the central M6 screw can be removed...these are only there to provide “cone error” adjustment, and seldom used.

[Waldemar]

2 hours ago, Merlin66 said:

The two smaller screws on either side of the central M6 screw can be removed...these are only there to provide “cone error” adjustment, and seldom used.

I think it is the M6 screws that are in the way, not the two screws next to them.
The M6 screws stick out and prevent the dovetail to go in deep enough.

A picture from the side would explain everything...

[Merlin66]

Yeah,

That's why I said the solution was to replace them with countersunk screws.............................

[david_taurus83]

Where the M6 bolts are, you could drill an 8mm hole down into the bar just enough to sink a cap head bolt. I've a dovetail somewhere where I've done that but cant find it otherwise I'd post a picture to show what I mean.

[Waldemar]

Just take 'm out would work as well... the 4 M5 screws are strong enough,

[Taff]

Hi' Thanks for your help and advice on the subject.Because my Sky Watcher 102 sort tube a longer dove tail won't be useful, so with the two bolts being in the way  when i place the dove tail to the mount i am thinking of putting the bolts in the other way and see if that will work for me cross fingers.Mark

[Geoff Lister]

If you remove the rear M6 bolt, but leave the front one, you can slide the dovetail plate rearwards into the clamp; and if the clamp pressure releases slightly, the front bolt will act as a stop, preventing the OTA sliding out completely. This is what I did with my ST120.

Geoff

[Merlin66]

Waldemar,

The two smaller screws are not connected to the tube ring, they just push against the ring......

[Taff]

I will give that a go  what you done Geoff.Mark

[Geoff Lister]

My ST120 was supplied as a package with an AZ3 mount. The rings for the ST120 are bolted to the top plate of the AZ3. This is fine for using the ST120 on the AZ3, but there is no flexibility to use the ST120 on other mounts, or other OTAs on the AZ3. This is my solution:-

Dovetail rail with the ST120's rings attached

The bolt in the centre, at the right-hand (forward) end of the rail, stops the rail sliding rearwards out of the clamp.

14 hours ago, Merlin66 said:

The two smaller screws are not connected to the tube ring, they just push against the ring......

Yes.

With my modification, the 4 cap-screws are mounted from the ring side, with tapped holes in the rail, and clearance holes added to the rings. If I remember correctly, I mounted the rings on the rail with the 2 large bolts, attached the OTA, drilled 4 pilot hole marks in the rings (being careful not to damage the rail's threads), disassembled and drilled the rings' clearance holes. The tippex marks on the rail and OTA body indicate the balance point for OTA+finder+diagonal+eyepiece (just under 4kg in total). The rail came with 2 photographic tripod mounting tapped holes (1/4" - 20 UNC), and the forward one is close to the balance point; so I could, if necessary, use a photographic tripod and the ST120 (probably a case of "tail wags dog").

This is the reciprocal modification to the top of the AZ3. The original ring mounting hole can be seen off the end of the wooden block. The block is attached to the AZ3 with (shortened) 6mm coach bolts and wing nuts for easy removal - although I have not had to remove them yet. The clamp is attached to the wood block with 3-off size 10 x 1" screws.

Geoff

 

[Taff]

Thanks' to everyone for your help and information  for the advice.Mark