Making a Moxon Vice with Derek Jones

I’ve looked at a couple of variations of the Moxon vice in the last couple of years and in that time I’ve built a fair few of my own; some quick and easy from offcuts and redundant hardware and others more swanky and convoluted. Each one has helped with the development of the next in the time-honoured tradition of a maker of things. Fundamentally the design has remained the same – a portable, wide twin screw vice set in front of a small integrated worktop with dog holes. The original self-imposed brief was to deal with what seemed to me to be a missed opportunity with the majority of traditional Moxon style vices which are a simple two jaw affair; a front and a back that elevates your sawing position to one more suited to accurate work. There’s nothing wrong with that if all you want to do is hold things tight.

I’m still using the first Moxon I built so I’ve had plenty of time to evaluate its worth. It’s a rare occurrence when form and function blend in perfect harmony first time round but of all the things I’ve made from scratch over the years this design is about as close as I have ever got to achieving that end. However, it wasn’t as calculated as I’m making out, serendipity also had a hand.

Less in more

Built with the intention of touring in mind I quickly discovered my first Moxon (we’ll call it V1 from now on) was on the heavy side. In his retirement from professional boxing and as a commentator and boxing pundit, Henry Cooper used to refer to fighters as ‘punching above their weight’. The same can be said of many a workshop accessory. Things built to reside in the workshop often assume a robustness beyond their needs, which is all well and good for a static item but not quite so welcome on a portable one. Admittedly the V1 was made from offcuts from my local timber yard so I bargained hard with the yardman and made the most of the generous slabs and his good nature; a slightly over engineered example was the result.

My second proper Moxon (let’s call it V2) was a special order version that came with a request for some fancy dovetails. It was made from thinner, off-the-rack boards, and with the customer’s own hardware it was lighter than my first Moxon which featured the Bench Crafted kit. With a nod towards a houndstooth style dovetail pattern at the front it veered away from my original intent that the vice should not conform to any particular aesthetic hierarchy but have its roots firmly planted in function and utility.

I kept to these principles for my third Moxon (we should call it V3) and stayed with the thinner stock but went back to the Bench Crafted hardware. As well as the sequencing of the build I looked at the method of construction to reduce the number of procedures and arrive at a design that could be taught and built by a group of mixed ability students. My fourth Moxon exists in my head for the time being and tackles a few bugs that surfaced while gluing up – more procedural than technical. Follow this plan and take note when you get to that stage and you will give birth to V4 before I do.

Easy mistake to make

The base frame or back end of the vice is pretty straightforward, just chunky through dovetails joining the back of the frame to the sides. A no frills, tight fitting joint is all that’s required. I’ve been working towards cutting these dovetails freehand and being able to assemble them straight from the saw, apart from trimming to the baseline. To do this with any degree of confidence you need to get to know your saw, your marking knife and your material and then work out where the margins are for cutting. I heartily recommend the process for a couple of reasons.

Firstly, it’s a whole lot quicker, secondly it will make you really concentrate on sawing a straight line and not just following a pencil line. These are the diesel engine equivalent of dovetails, the ones you want to be able to cut all day long without batting an eyelid, that’s how the majority of joiners a hundred years or more ago would have regarded them – just joints, as many as you can as quick as you can. And thirdly, when the time comes to cut dovetails that do require greater precision you’ll find the process less stressful and so much easier. It’s here that we’ll begin.

Starting with the back jaw of the vice, which is the front of the frame, mark a line all the way round the ends of the boards to define the horns. These are used for clamping the vice to your bench top or any other convenient work surface. With that done now rip the board down its length to remove a section that will become the horns. We’ll call it the horn section. If this doesn’t sound like fun to you just make the parts as two separate components from the outset. Remove the waste on the upper part as this will define and be equal to the width of the frame. Now mark out the base lines for the dovetails on the frame sides and back jaw. Note the dovetails don’t run the full depth of the sides.

What big teeth you’ve got

I’ve looked around and asked a few makers if they were aware of any hard and fast rules about laying out houndstooth dovetails and the general consensus is that there aren’t any as long as the general ratio or spacing doesn’t structurally compromise the joint. One suggestion from Neil Erasmus in Australia recommended a 1:10 ratio for the dovetails instead of my more usual 1:6. The fine tapered proportion is a very tailored look. For this example I’m squeezing a lot of detail into a short span and couldn’t quite get things that tight. My advice, however, is to draw a few different patterns with varying ratios to find one that works and suits the application and the tools you have to hand. Note that increasing the length of the short pin brings it closer to the walls of the tail. In this instance I found that 1:8 ratio was the right balance.

Drop the baseline

There’s not a lot of difference between cutting mixed sized tails from regular ones, just be extra careful about which side of the line constitutes waste and you won’t go far wrong. When you have them trimmed to size you’re ready to transfer the lines to your pin board. I struggled to get this right on V2 with my choice of marking knife so instead set a marking gauge to the depth of the short pins and did it that way. You can be generous here and mark them a fraction longer than required and trim them back later. If you’re not in the habit of identifying the waste area when cutting joints then please just try it this once. You’re going to be cutting on alternate sides of a series of knife lines that aren’t always that obvious at first. You can ask me how I discovered this later.

I’ve been quizzed a few times why I didn’t put a wide chamfer on the front jaw of my Moxon to help with some sawing operations and it’s simple really; it just reduces the front jaw to a clamping component for the rest of its life and it doesn’t gain you much in the sawing stakes either, see the earlier article in F&C 233. For lapped dovetails and this houndstooth pattern, removing the waste between the pins is quickly done with just a chisel and that means chopping vertically as well as horizontally. A thicker top edge on the front jaw gives you somewhere to rest a chisel.

Over time you may find that the top edge of the jaw gets a little scuffed but the extra thickness also means you can clamp a piece of fresh timber with nice crisp edges along the baseline of the joint. To make sure it remains flat in the middle take a couple of shavings off the ends of the strip to create a gentle bow and clamp it concave side up to the top of the jaw. It’s also a really useful reference for paring the walls of the pins. Issues concerning the workpiece deflecting in the jaws are mainly down to the rigidity or lack of it in the back jaw of a standard Moxon.

Bottom half

Dry assemble all four parts of the base frame, turn it upside down and place the horn section on top of the frame sides lining the outer face of the sides with your knife line. Transfer the thickness of the sides to the horn section from the internal face of both sides. Use a marking gauge to generate a mortise and tenon on the respective parts – a mortise on the horn section and a tenon on each side below the dovetails. If you’re going to make a mistake anywhere, here’s where it will happen. That little bit of waste on the dovetail side of the tenon needs to go. It looks and feels strange to be destroying that half pin opening but destroy it you must. Excavate your mortise however you wish and familiarise yourself with how all three components go together. 

Easy buttons

I consider this method of making buttons to be an improvement from V1. A lot of work goes into making a flat worktop and usually the first and last inch at each end goes in the bin when it comes to dimensioning. The low-fat answer to this is to add those inches to your cutting list and make the worktop a little longer than it needs to be and make some buttons in the process. Start by gauging a line to the size of the groove you’re going to cut into the internal face of the frame. This material will be the tongue and it’s still attached to the end of the worktop.

Use a rebate or shoulder plane to create a shoulder and then saw down to the gauge line. Chop the bulk of the waste away with a chisel and then finish off with your rebate or shoulder plane. Try not to overshoot the line. Depending on the size and number of buttons you need repeat the process at the other end. Mark out each button then drill and countersink the screw holes before cross cutting the strip of buttons from the worktop. Chop them off as required and set them aside making a note to do this next time you have a solid worktop to fix.

Put a cross in the box

You’d be surprised how many people get it wrong when they’re asked to put a cross in the box. This tiny X isn’t just for show, it does an important job. When it comes to gluing your base frame together you’ll start with the dovetails, front back and sides to construct the base frame. Don’t try and do things the other way round. When you’re happy with everything and only then can you plant the horn section onto its tenons. The squarer the base frame is the easier you will find to locate the horn section. If it’s tight you should find the X cuts allow the tenon to compress in all directions to help with the initial assembly and fine adjustment. You may want to treat the glue-up as a two-step operation, making it a V4. Driving the wedges into the grooves expands the tenon back to all four corners without applying stress directly across the grain where it could split the bottom out of the horn section. Nobody wants a split bottom. Especially in the horn section.

Clamping caul

Soft wood makes a great clamping caul and also prevents you from bruising the surface of show pieces during glue up and assembly. If you’re working on your own don’t struggle with trying to hold the block in place with one hand while you attempt to tighten the clamp with the other. Just dab a tiny spot of glue (hide is best) on one or two points along the caul. You’ll easily be able to remove it later with a saw or chisel if it won’t come free with a little tap.

Beef it up

With a standard two jaw Moxon when you’re done with sawing, you’re done with the Moxon, it’s served its purpose and can now be put away. This version, however, will be your workstation from the transfer of tails to chopping out waste and then final adjustment before it has to go back on the shelf.

We’ve already looked at the design of the front jaw but so far haven’t mentioned that most of the other functions would be hard to accomplish well, if not altogether impossible without the addition of a worktop. The clamping face of the rear jaw is made up from the edge of the worktop and the internal face of the rear jaw, the former being fixed on top of the latter. In this configuration each component effectively braces the other so the structure is rigid in all directions.

The result is minimal deflection while chopping out waste on lapped dovetails and with some carefully positioned dog holes a rigid platform on which to transfer lines between components. The key to this is partly due to the thickness of the worktop but mostly because of a couple of pegs keeping the two pieces in registration but allowing them to move should the conditions require it. On V1 I used dowels, on V2 I used Dominos and on this version I’m using half loose tenons (if there is such a term) because I’m expecting to build these in a class environment without the use of power tools at some point in the future.

For the record, all three work as long as you follow a couple of basic principles. Number one, only use pegs along the front edge, i.e. the rear jaw and not the rest of the base frame. Number two, position the worktop with a slight overhang of about 1mm when you first put them together and number three, don’t glue the worktop to the rear jaw or any part of the base frame for that matter. With the pegs at the front and buttons holding the worktop in place all the way around the top can expand and contract, front to back, while still staying flush with the internal face of the back jaw.

This final step is optional but well worth considering if you have dog holes in your main bench and like to use holdfasts. Drill the same pattern of holes in the Moxon worktop as they appear on your workbench. In use the Moxon is placed with the internal face of the back jaw sitting flush with the front edge of your bench, and as the Moxon worktop is sitting on top of the back jaw, its front edge is similarly aligned so there’s your template. If you’re happy with the idea of using holdfast through the Moxon you may discover you don’t have a use for the horns at each end of the back jaw. Removing them is tempting but it could limit your clamping options if you want to use the Moxon on a surface other than your workbench.

Flat and square

That slight overhang I mentioned now has to be levelled off so the worktop edge is flush with the internal face of the back jaw. The best way to do this is to fit the worktop in place with the buttons and put the whole Moxon in a vice. Aim to get the entire surface as flat as you can in both directions and square to the worktop including the top edge of the front jaw. Shape the ends of your front jaw if you like or leave them square, it doesn’t make a difference as long as you can get a clamp on the horns. It’s unlikely that your dog holes will interfere with the threads unless you decide to reduce the amount of available adjustment by having more thread on the inside of the Moxon. If this is the case I’d guess the dog holes on your bench are very close to the front edge. Do the maths here first and adjust the spacing between the threads and perhaps consider only drilling for the back row of dog holes. I’ve resisted the temptation so far to drill holes in the front jaw for dog holes although I can see it may create more clamping options. The Bench Crafted hardware is brutish so could easily fracture the jaw at a weak spot in my opinion. Maybe an additional front jaw for this purpose would be an option. Perhaps we’ll call it V5.

Further reading