To me, the one big critical flaw in the VSP design was the lack of a dovetail/saddle provision. This mount was designed so that the scope OTA rings are bolted directly to the mount head. There are two holes in a flange on the mount head to attach the rings - this results in a fixed spacing of the rings with no options for changing the distance between the rings. This was an annoyance for some time, but not a deal-breaker. I mounted several scopes on the VSP and the lack of dovetail/saddle facilities did not become a major issue until I bought my Synta 6" Mak-Cass.
The Synta 6" Mak-Cass has a Vixen/Orion dovetail attached to the OTA which cannot be removed easily - not without removing the meniscus to access the captive bolts inside the tube which hold the dovetail to the tube. This is more surgery than I was comfortable with on my new scope. Worse, the stock dovetail runs the entire length of the OTA - leaving no gaps or space to use hinged mounting rings. Apparently you either mount this OTA with a dovetail-compatible mount, or you use the OTA as a paperweight. Using rings was not an option. So now I had a nice mount and a nice scope, but I couldn't put the two together. I had a problem.
Due to the shape of the VSP mount head, you can't simply bolt a flat plate with holes tapped in it to the mount head - it won't sit flush because of raised ridges which are cast into the mount head. Any piece of metal that is going to be bolted to the top of the head must be shaped to mate with the ridges on the mount head - a minor PITA and a deal breaker to a guy like me without access to a metal-working shop. I looked around the garage and through my junk piles, looking for some low-tech solution to this problem - something I am usually quite good at. "Jerry rigging" is an artform I have mastered, but in this case, I couldn't find any cheap solution that I would trust to hold my $500+ OTA.
So I started thinking about the people I know. Who do I know that can fashion some kind of adapter for me? Right away a name popped into my head - Steve Forbes, or "Telescopeman54" here on CN.
I've done a bunch of gear deals with Steve over the last few years on AstroMart and I know that Steve is a talented tinkerer and fabricator. He has fully-stocked shop and the skills I lacked. So I contacted him and asked him if he could make an adapter for me that would allow a modern dovetail equipped OTA to be mounted on my old-school Vixen Super Polaris GEM.
He said "No Problem, piece of cake, send it to me."
So I boxed up the mount, minus the tripod and counterweights, and shipped it to Steve via USPS Priority mail with Insurance and a tracking number. It cost me about $30 each way to ship it, so about $60 total cost for shipping. I could have saved a few bucks by shipping Parcel Post or UPS, but I didn't want to wait over a week each way in transit. $30 and Steve had my mount sitting on his front porch in about 3 days.
Within a couple of days, I got an email back from Steve - complete with photos. It showed my VSP with a block of some kind bolted to the head - this "block" is a piece of steel that Steve machined to fit perfectly flush against the VSP mount head - the raised ridges on the head mated with grooves Steve had provided in the adapter block. The adapter block is then bolted to the mount head with two large rosette knobs which Steve provided from his personal junk pile. Any standard bolt/nut combination would work, the rosettes just look better and make swapping out the adapter a breeze.
The adapter block simply sits on top the VSP head, bolted securely in place. The block has a slot in the top of it to accept the OTA dovetail bar - two rosette knob tightening screws lock the dovetail into the adapter/saddle.
Steve painted the entire adapter block black and supplied me with the necessary rosette knobs. When I got my mount back in the mail, I was amazed at how this simple modification had greatly improved the utility of my old near-obsolete mount. I could now mount any scope to my VSP using a widely-available Vixen/Orion style dovetail bar. The Synta 6" Mak-Cass now rides perfectly balanced on my VSP and the entire rig sits ready to go at a moment's notice in my computer room.
I share all of this because I know there are a lot of Vixen Super Polaris mounts out there in use. And I know many of the owners may be like me - frustrated by the lack of a dovetail provision on an otherwise superb mount. I asked Steve if he would make these adapters for other VSP owners, and he said "SURE". So, consider this post a "heads up" for VSP owners - if you want your mount modified to take modern dovetails, contact Steve. He'll hook you up.
What did this adapter cost me? Well, first off, it cost me about $50-$60 for shipping expenses to and from Steve's shop. Steve and I had done many deals before, including several gear trades, so we worked out a "unique" swap deal - Steve gave me the adapter and I hooked up Steve with some astro goodies he was needing. So I didn't pay a set cash fee for his services. Anyone wishing to have Steve fabricate an adapter will have to chat with him and hammer out a deal. I can just say that I am very happy with the final modification.
Here are some photos of the modification...
First, here is the final product - my 6" Mak riding on the VSP using the dovetail and modified "saddle" adapter.