I started with one of those chinese-made wood-threading kits from Woodcraft. The threads made by the tap didn't match the threads on the screw. Woodcraft returned my money and generously gave me some free wood. Then I graduated to the Beall system, and upgraded my router. Chewed through a lot of dowels, and never was able to create anything that worked. Beall even sent me a replacement part at no charge, but by then I was thoroughly disgusted with the entire process.
During this time I industriously pulverized massive quantities of fir and maple, clearing entire hillsides of native forests. Beavers were lining up outside my door, waiting for a free meal. The local pulp mill wanted to sign a contract. It was that bad. But I both exaggerate and digress, as I'm sure you've noticed.
The 8/4 hard maple chosen for the project was set aside at the bottom back of the wood rack. A few months ago, it was moved to a corner while re-arranging the wood pile. The sight of it still provoked muttered curses even after the passage of much time.
Then over the holidays I had a few weeks off, some of which was spent sitting in the shop, contemplating the contents, wood inventory, unfinished projects, etc. When I could look at the maple without inciting an internal riot, I figured I had a chance to do something with it - other than reduce it to matchsticks, that is. A new LV Shoulder Vise Screw also sat in the corner next to the maple, a victim of another abandoned project.
A few cobwebs were brushed aside, a rusty cog started to turn, and the beginnings of an idea were germinated. Hmmm......still a few days before Christmas.....I dashed inside to the computer, and added a LV shoulder vise screw to my online wish list. There was an off chance, even at this late date, that it might happen.....
And it did. The second shoulder vise screw appeared under the Christmas tree, and I was off to the races. A few hours in the shop, and I was able to produce a workable Moxon vise.
Boring out the holes with the 14" brace and Irwin expansive bit. That's a bit of work, would really be tough without that big brace.
The front chop of the vise sags a bit, so I installed the UHMW inserts to provide some stability. The screws action is pretty smooth now.
The tail end of the screw was countersunk and screwed on to the back of the Moxon vise. I didn't use the countersunk screws that came with the shoulder vise screw, as I had to turn everything around and attach from the back. So I used pan head screws, and they worked fine.
This thing is a beast of a vise and works great. The shoulder vise screws are a bit of overkill, but they work well. It was one of those "Use what you got" moments, so I'm good with the results.
Now on to doing a few dovetails!
But First, A Modification....After using it a bit, I decided to switch things around a little. The current setup works, but it was a compromise. I did it this way because the brackets/nuts were too large to attach to the back without chopping a mortise in the bottom support strip of wood (a symptom of picking up this project and making changes after almost a year). The best way is to move the brackets/nuts around to the back - this way the threads can stick out the back instead of the front. A pic is worth a thousand words.....
You can see where I had to cut away some wood to get the bracket in place. Previously, the end of the screw had been held in place, fixed, by that little green thingamajig. This made the entire length of the screw stick out the front, which would get in the way constantly. I think this new configuration will work better in the long run, even if I had to hack up the wood a little. Compare the first pic in the thread to this last pic and see if you don't agree.
One Last Note....Several individuals have informed me that the first arrangement, with the nuts/brackets on the front "just doesn't work" or is "plain old wrong". Well, I must agree it isn't the best; the second arrangement works better. But the first setup actually worked pretty decent. I think the main reason it did work was the holes in the wood are 1.5" and the threaded rod is 1.08". With the UHMW providing some support yet being flexible, there was enough play in everything to allow some independence in each screw.
It just goes to show you that there is more than one way to skin a cat. People choose different approaches for reasons that make sense to them; often this is not clear to the casual observer. It pays to keep an open mind and leave the dogma at the door.