There is no denying that the most prominent name in dovetailing jigs is Leigh! Since the early '80s, Leigh have been manufacturing and retailing dovetailing jigs to woodworkers, with their now famous D4 model jig recognized as one of the best available for the woodworking hobbyist or professional.

Since then, Leigh have also manufactured a mortise and tenon machining jig, and more recently, the little brother to the D4, the D1600 jig, which is the subject of this particular review.

Out of the Box
The D1600 comes supplied in a well packaged box with an assortment of bits and pieces, so separating and sorting everything out on a large enough surface is recommended to avoid confusion. The first item you will probably be keen to pick up is the DVD included in the kit. No doubt you will have this in the DVD player and running not long after opening the box. I love when manufacturers include DVDs. It's that little extra bonus you don't find in many product boxes. The DVD provides an excellent overview on setting up and using the D1600 jig, and it is well worth watching before you get stuck into using the jig.

The most important item you will want to read through is, of course, the user manual. This ring-bound resource is full of step by step instructions for assembling and using the D1600 to construct all the types of joinery the jig is capable of producing. It is also a little more detailed than the information provided with the DVD, so don't just throw it back in the box. It's meant to be used in the workshop as you craft your fine woodworking item. Keep it close by and handy while you learn the ropes of your new D1600 jig.

A bag of various knobs and fixings are included for initial assembly and setup of the D1600. One of the first steps outlined in the assembly process is to build a base for the D1600. This can be made out of any stable material, but plywood or MDF are probably best suited for the task. I used 3/4" chipboard as I had plenty available at the time and it has worked fine for me so far. The purpose of this base is to provide a wider footprint and to add a surface to which you can clamp the jig/base down more efficiently and safely to a workbench or work surface. Full instructions and a measured drawing for cutting and drilling the base is provided. There are only a couple of other basic assembly steps to complete and the D1600 is ready to use. It took about 30 minutes to construct the base and assemble the jig fully ready for use.

Before you get started using the jig it is recommended to acquire several boards of cheaper softwood, usually pine or poplar, to use as sacrificial practice boards before getting your teeth into more expensive wood. I would also advise to go back to the DVD and look at the examples given, and also take note of special safety precautions mentioned. The last thing you wish to do is to destroy your new investment!

Leigh D1600 Features
So what makes the Leigh D1600 so special? I mean, you can buy cheap dovetail jigs from a number of other suppliers for basic dovetailing tasks... The keyword there is basic. The inexpensive dovetail jigs available are somewhat limited in the types of dovetail joints they can create. Many will only be able to make half-blind dovetails with pre-set pin spacing. What makes the Leigh dovetail jigs so popular is that they offer, among other features, fully variable dovetail joint spacing, i.e. you can position the pins and tails wherever you like across the width of the joint, as well as choose how many pin/tail joint combinations you desire as well. The cheaper jigs usually have pre-determined spacing that is not adjustable, which makes it hit and miss as to whether you can make a half pin on both edges of the joint, a trait which seems quite desirable in dovetail joinery. The Leigh D1600 can of course ensure you have half pins on each end of the joint, as well as variable spacing between these, and this is a great asset as it allows you to create joints that appear unique and different to the next. The D1600 can also be fitted with outer dovetail type template jigs to create more artistic-looking joints, but we will look at those in part 2 of this review later.

The D1600 is indeed capable of producing a wide array of joint types. No longer are you restricted to just half blind dovetails with the cheaper jigs on the market. The D1600 is capable of producing half-blind dovetails, through dovetails, sliding and angled dovetails, as well as rabbetted and end on end joints too. And then there are angled and offset dovetails, to name just a few more. You can create joints up to 16" wide with the D1600.

Build quality is also one of Leigh's best assets. All components are solid in construction and are precisely machined for accuracy. When you pull the D1600 out of the box, you can immediately see the level of quality it is built with. That higher price tag is quite justifiable in this case. You are buying a quality, well-machined and finished dovetailing jig that, if looked after carefully, should last a lifetime, and then some. The main body of the jig is CNC machined one piece aluminum extrusion that is very rigid and provides a solid working reference surface to mill wooden dovetail (and other) joints. In addition to the main jig body, the D1600 also ships with:

• Dovetail Cutter Nos. 80-8, 140-8 and 120-8
• 2 Piece Brass Template Guide (711TP)
• Cam Action Speed Clamps
• Cross Cut bar
• Screw Driver
• Fully illustrated manual
• Bridge piece material

So you get pretty much everything in the kit to start producing great dovetail joints. All you need to supply yourself is a router. The router either needs to have its own 8mm collet (to use the included 8mm shank router bits supplied) or have a 1/2" collet (to use the 1/2" to 8mm collet reducer supplied in the kit). Additionally, a plunge router will provide more flexibility and ease of use, and Leigh recommends using a router with at least 1.5HP rating. Your router will also need to be compatible with the supplied Leigh Template guidebush (code 711TP) to use it with the D1600. A mounting adaptor system which includes a range of fittings to suit many routers is also available. I would recommend checking out the Leigh pages directly to determine whether your router is compatible. See http://www.leighjigs.com/ugs-16.php
For what it's worth, I found none of my three routers actually fit the supplied guide bush. The routers I own are not popular models, and not readily available in the USA (I am in Australia) so this probably accounts for the compatibility problem. If you are in the USA, chances are your router will most likely be compatible, or there will be an adaptor to suit. Again, check the above webpage for compatibility. I ended up buying a new router which is compatible to use and test the D1600 with... Good excuse for a new tool :)

Using the D1600 Jig
So once you have set up your jig and read through the basics of the manual, it's time to start cutting some wood. Initially, you will need to do a few test runs on different thickness material. This is so you can "calibrate" the D1600 and scribble down some important figures so your accuracy can be repeated later on. This is an important step in the process of using virtually any dovetail jig, not just the D1600.

In order to describe the process of creating some dovetail joints using the D1600, I'll copy and paste, for simplicity sake, the instructions available on the Leigh website, basically because the instructions are hard to beat and I don't think I could explain them any better to be honest! I'll then give some of my own comments and opinions, or highlight any issues I had crafting these joints following each procedural description.

Through Dovetails The D1600 Dovetail Jig cuts through dovetails the same way as its big brother, the D4. Here's how you do it: Cut Through Dovetails 1. Position the finger assembly in the Through dovetail Tail mode . Icons identify joint type. The readable scale area always faces you and is colour coded grey for Through and green for Half-blind. There is just one scale setting to rout your Through tails.   2. Using the included 7/16" template guidebush with the included ½" 8 degree dovetail bit, the template guidebush steers the router along the guide fingers, ensuring precise, accurate routing of the Through dovetail sockets. All bits with 1/4" or 8mm shanks work within a 7/16" o.d. template guidebush.   3. Individually adjustable guide fingers let you quickly set up custom layouts to suit your work. You can create any joint layout you want-the guide finger spacing is infinitely variable. Whether you want a symmetrical or asymmetrical joint. Now rout all the tail boards.   4. Flipping the finger assembly front to back switches the mode from Tails to Pins . 5. Adjust the pin scales to make a precise, recordable and repeatable setting for each bit combination. The pins will fit the sockets perfectly, joint after joint.   6. Install the matching straight bit in your router. The template guidebush follows the angled guide finger surfaces to cut perfectly mating pins. 7. As you can see there's just one setup of the guide fingers, so perfect pin and socket alignment is guaranteed, no matter what joint layout you've chosen. That's all there is to it…perfect Through dovetails!     A Perfect Fit Adjusting through dovetail joint tightness is very straightforward. Towards You is Larger In Through dovetail Pin mode, moving the finger assembly towards you lets you cut slightly larger pins, making the joint fit tighter. Away is Smaller Moving the finger assembly away from you lets you cut slightly smaller pins, making the joint fit looser.

The through dovetail joint was one of the first ones I attempted to create using the D1600. I'll say now that the first few joints take quite a while to make. This is not because of a deficiency or issue with the D1600 itself, but more of a learning curve to be worked through, primarily attempting to get all the required steps into your brain and then reproducing these with your hands and router. I found that after I had made three or four accurate through dovetail joints, the process became a little more engrained in my mind and I no longer needed to reference the manual for step-by-step instructions constantly, which was the major time consumer in the beginning. The D1600 can create through dovetail joints on boards up to 13/16" thick. After I had learnt how to use the jig, I found crafting dovetail joints was very quick and efficient using the D1600. I could probably create 4 joints for a dovetailed box faster with the D1600 than marking out just one joint doing it the "old fashioned" way.

The flipping of the finger assembly is the unique part of the D1600 jig. One one end the fingers are machined/shaped to produce dovetails pins, and on the other, dovetail tails. Because the fingers are secured down with screws and the jig is referenced on both ends, as you flip it, the fingers remain perfectly aligned, ensuring your joint comes out nearly perfect each time. As mentioned above, if the joint fit is loose or tight, fixing the problem is very easy indeed. Simply slide the finger assembly forward or back as required and mark down some settings for later use. The ability to infinitely space the pins/tails in any configuration you desire is a great feature.

Referencing the pin scales makes the job of setting up the D1600 for accurate joints quite simple. I would advise, however, that when you reference or secure the finger assembly down at a specific point on the scale, look straight down at the scale from above to ensure there is no parallax error in your reading of the measurement. The system employs a 7/16" guidebush which rides against the fingers on the dovetailing template. Depending on the type of dovetail joint you are making, you generally use either the special 8mm dovetailing bit supplied, or for the pins, a straight cutting bit (also supplied). A half-blind dovetail joint only uses a dovetail cutter for both parts of the joint.

Also, as you rout the joints, be aware of which part of the fingers the guide bush needs to ride on. After a few goes, it will become second nature, although if you haven't used a dovetail jig before, practice with no cutter installed in the router just gliding the router base over the finger assembly. Good balance of the base plate on the finger assembly will ensure good results. A nice, well-balanced router also helps here. If you can get a good feel of your router and master controlling it with your developing fine motor skills, you will have far less hassles when creating joints on the D1600. But in saying this, it only took me a few minutes to master handling the router on top of the jig. I prefer to use a smaller and lighter router on the D1600. it just seems a little easier to manage. But like anything, practice makes perfect!

In saying that however, in terms of mental brain power needed to use the D1600, there is very little. You just have to follow a few key rules, one being not to raise the router (for plunge routers) with the dovetail bit installed. You will soon break it! I almost did this, but stopped myself just in time. Phew! It's a good idea to switch off the router and keep it firmly in place on the finger assembly until the router bit comes to a complete stop. This will ensure you do not damage any parts of the D1600 jig.

Through dovetails can be used for a wide variety of projects. They make great looking joints for all sizes of boxes or chests. And if you use different contrasting wood species for the front/backs and sides, the joint really pops when a finish is applied. It looks stunning and very beautiful as a finished joint. You will probably never consider a butt joint again. And not to forget overall joint strength as well. Because of the dovetail design, there is an abundance of surface area for glue to cement itself to, providing one of the strongest joints possible in woodworking.

Half-blind Dovetails Almost every dovetail jig that was ever made to cut half-blind dovetails cuts them the same way. A single dovetail cutter cuts both the pins and tails. However, unlike template jigs, the D1600 allows you to change the size and spacing of the tails. How to Cut Half-Blind Dovetails 1. If the finger assembly is in the through dovetail mode, simply slide it off the jig and turn it end for end. Now you are ready to make half-blind dovetails.   2. Set the pin scale to the thickness of your drawer side (tailboard). The readable scale faces you and is colour coded green. 3. Use the included 7/16" template guidebush and the included #120-8 dovetail cutter. Or use on of the other dovetail bits listed. 4. Bring the drawer front (pin board) up against a scrap board for quick alignment. Now rout your tail sockets leaving the pins exposed. 5. After routing all your drawer fronts, simply rotate the finger assembly toward you to access the half-blind tail mode (drawer side) . 6. Again, set the scales to the thickness of your drawer side. 7. If you have wider tails, simply slip in the provided bridge piece material. Bridge pieces ensure precise routing on the backside of the tail and guarantee a perfect fit with the tail socket resulting in maximum glue surface area in the joint. 8. Now rout all the tails on all drawer sides.   A Perfect Fit Adjusting half-blind dovetail joint tightness is very straightforward. Lower is Tighter Lowering the bit cuts a narrower opening between tails and removes a little less material from the sides of the pins, making the joint tighter. Higher is Looser Raising the bit cuts a wider opening between tails and cuts away a little more of the pins as well, making the joint looser.

Cutting half blind dovetails is not a lot dissimilar than through dovetails on the D1600. If anything, they are perhaps a little easier and quicker to make once you have the process figured out. It is perhaps slightly speedier because the same dovetailing bit is used to cut both the pins and tails for the joint. There is a difference in making adjustments for tighter/looser fitting joints however. Whereas with through dovetails, the finger assembly itself is adjusted, with half-blinds, the actual router bit is raised or lowered to make joint fit. On the D1600, you can make half blind dovetails on boards up to 1" thick.

Half-blind dovetails are stock standard joints for constructed solid and strong drawers. Because of the pin and tail design, it is almost impossible to pull the front piece of a drawer away from the sides. Dovetailed drawer joints are also a sign of quality woodworking in a finished cabinet, dresser, or tall boy. Half-blind dovetails allow you to hide the joint also when the drawer is closed, the joint design only being visible on the draw sides.

A point worth mentioning here in relation to the cam clamps used to secure wood or material to the D1600 jig... You should be careful with how much pressure is applied, and learn to use the cam clamps properly to avoid damage to the jig. Also, the right amount of pressure will not only hold your workpiece securely, but will also eliminate any marking of the piece, which is possible with softer timbers when the cam clamps are engaged too tight. The clamps hold extremely well when tightened correctly. It really is a quick and efficient design employed on the D1600 jig. Kudos to the R&D department!

One particular step required with half-blinds, especially if your finger spacing is wider than 3mm apart, is to cut some small strips of the included bridge material to insert into between two tail end fingers on the jig. The hardened plastic strips are easily cut with a fine saw. I used a hacksaw followed by a quick edge cleanup on the belt sanding station. You will need to cut them to length accurately as they sit between the fingers and are shaped to wedge into the milled ends of each finger. They are a friction fit, but won't move during use. They provide a flat reference surface between each finger so the dovetailing bit cuts the inner tail sections properly for the half-blind dovetail joint. The bridge pieces are re-usable, so keep them handy!

The process in general is simple with these joints. Essentially you select a dovetailing bit and check the required depth setting for each bit (all info provided in the manual). You can then cut the tail pieces, and then the pins with the workpiece mounted horizontally in the top clamp. Once both tails and pins are cut, you can dry fit the joint. If too tight or too loose, simply adjust router bit height accordingly to correct. It's all very simple really.

Again, with our initial half-blind joint test, we came up trumps, producing a well-fitting joint that required very little sanding to complete it. This is a testament to the accuracy of the D1600 jig, and to the detailed instructions and explanations provided in the manual.

Sliding Dovetails Cut Sliding Dovetails 1. Set the finger assembly in the half-blind tail mode on the 5/8" mark. 2. Using the supplied 7/16" template guide and the included 1/2" 14? #120-8 dovetail cutter.   3. With the centerline of your socket marked on the edge of the work piece, line up this mark with the outside edge of the 3/4" vertical board. You have now perfectly aligned the socket to where the router bit will cut. Install the included crosscut fence and rout your sockets. 4. Now clamp the tailboard vertically flush under the finger assembly. Rout one side, rotate the board and rout the other side. Moving the finger assembly in will reduce the size of tail.

Sliding dovetails are the perfect joint for shelving projects in cabinets, although they can be used for other construction joints as well. With glue applied, there is virtually no need for any other fasteners to be used. However, they are also the perfect shelf joint for knock-down furniture as well, that is furniture you can disassemble later on if need be. Even without glue, this joint will hold plenty of weight and will remain in place (assuming a well-fitted sliding join).

The D1600 finger assembly is used slightly differently. Instead of actually using the pin/tail pieces as guide references, a crosscut fence is added to the edge of the guide fingers to provide a straight reference surface. After about 1 or 2 initial attempts, I was able to make perfectly fitting sliding dovetail joints with almost no effort at all.

Of course, sliding dovetails can be made using other methods as well, but having the option to create them on the D1600 jig is an added bonus. You can probably craft them a little quicker using a router, router table and some pre-calculated figures, and its perhaps a little easier this way, particularly if you are working with long boards which can be a bit cumbersome to use with the D1600, but for smaller work, the D1600's sliding dovetail option is pretty good.

RVA-1 Router Vacuum Attachment
Here's a great little accessory that works wonders with your router, and not just for use on the Leigh jigs too. The RVA-1 vacuum attachment is a device that attaches to your router via the standard fence mounting holes found on most models and allows hookup of your vacuum extraction system to remove the majority of waste material produced during routed cuts. It has a spring-type swinging vacuum port that allows the port to be set up close to the router bit, but will pivot out of the way easily should it come into contact with something during the cut, plus a small roller at the end of the dust port glides easily along the edge of a workpiece, allowing you to maintain the port as close to the cutting bit as possible in use.. When in use on the Leigh jig during cutting operations, I found the router grabs a high percentage of the dust and debris created. I have it hooked up to a Festool CT Mini vacuum system which provides great suction, and as far as I could tell, pretty much all the fine dust and debris is extracted efficiently during routing operations. Only some of the larger and finer shavings created when routing softwoods like pine occasionally managed to escape the suction from the RVA1 port, but this was most likely due to the debris being trapped between the workpiece and parts of the D1600 jig itself. The RVA1 attachment, which sits underneath the router base and can be arranged to be as close to the router bit, or as far away as desired makes an excellent improvement to any router, particularly for edge cutting and profiling tasks. Naturally, it is not as effective for dado or trench routing, but great for edge rebate work. It certainly beats the dust extraction features built into many routers as default, and I'd go as far as to say it's just as effective, and perhaps even more effective than the handy vacuum attachments shipped with the Festool OF1200 router which I have reviewed, and praised, previously. This RVA1 attachment is just that little more flexible, and with a wide dust port footprint too, to maximize coverage area. Even if you don't end up buying a Leigh dovetailing jig, the RVA1 would, and should be an attachment for your router that you should consider purchasing. Sold separately as an accessory and priced at USD$44.00 the RVA1 seems perhaps expensive for the materials used to make it, but in practical terms, and efficiency and general design effectiveness, it is worth every cent in my opinion. As I have said before, and I will say it again, I don't think you can spend enough on any system designed to reduce your exposure to airborne dust. It is a small price to pay to save your respiratory system, and it will save a LOT of cleanup time later on, that is certain.

Conclusion - Part 1
It probably goes without saying that the D1600, at least in my tests, has been shown to produce very well-fitting dovetail joinery, and even on the first attempt. In fact, if you follow the instructions carefully, it's very difficult not to produce a near-perfect joint on your very first attempt. Such is the design and the quality of the D1600 jig that makes this possible. I know I wrestled with more than a few bad joints trying to make my first few half-blind dovetail joints on my el-cheapo half-blind dovetail jig.

I know a lot of people often comment on the price of the Leigh jigs (retails for around US$359), and ask, "are they worth the money?" Well, I can tell you now that after using one for a couple of months now, the answer is a definite yes! It's very exciting to produce fine joinery on such a fine piece of equipment, and the results certainly justify the cost in my opinion. I know many woodworkers shy away from dovetail joinery because it is either too difficult, or too time consuming, but the Leigh D1600 at least appears to solve both those problems.

Of course, nothing would probably beat the thrill of crafting a perfectly fitting dovetail joint using a pencil, fine tooth saw and some chisel work, but if you don't have 20 or 30 hours to produce a couple of draw or box joints on your next project, the Leigh D1600 has to be the next best thing.

I am very happy with the results the D1600 delivers. I haven't come across an owner of a Leigh jig that wasn't happy with their product yet, and I can see why after finally getting my hands on one myself. If you have the money and are eager to produce fine dovetail joinery using power tools, definitely add a D1600 to your woodworking wish list.

End of Part 1 of Review

Leigh D1600 Review Part 2 - Isoloc Templates
Ok, as promised here is Part 2 of the D1600 + accessories review, looking at the Isoloc Templates and the Variable Guidebush System (VGS).

The Leigh Isoloc templates were primarily designed to provide something different in the world of half blind dovetail joints. While traditional half-blind dovetails feature straight edges, the Isoloc templates allow the user to craft equally strong joinery with more unique and distinctive joinery patterns.

We received the I1600B Isoloc Template designed for the D1600 jig, but the templates are also available for the larger D4 jig too, and template designs are numerous. Each Isoloc template allows two different designs/styles of joinery to be created. The I1600B offers the "clover" and "bear ears" patterns, which are probably the most unique of the set to date.

Like the normal finger template for the D1600, the Isoloc templates can be used for many types of dovetail joints, including through-dovetail and rabbeted dovetails, even inlaid dovetails, but for the purpose of this review I chose to focus on the half-blind dovetail joint, as this is what the Isoloc templates are primarily designed for. If you wish to try the other joint types, the included product manual that ships with the Isoloc templates will provide step-by-step instructions on creating all the other types of joints. For the record, I crafted one test through-dovetail joint and it worked very well first go. But let's get back to the process of machining some unique half-blind Isoloc joints using the I600B template.

To begin with, the template mounts to the D1600 jig just as the finger assembly does via the two end support arms. Unlike the finger assembly the Isoloc templates are fixed, so there is no adjustment available in terms of spacing pins. This means that there are certain dimensions of material that will guarantee half-pins on each end of the joint, and anything else you must compromise upon. Because of the actual design of the Isoloc template and the unique patterns it creates, trying to make an adjustable version of this template would be a bit of an engineering nightmare if you ask me. I do not see this as a problem. Just something to keep in mind. The product manual offers a wide array of material sizes that will guarantee perfect half pins on each end of your material, if that is an essential element to your project.

The I1600B Isoloc template mounted on the D1600.

Each side of the Isoloc template features a different joint pattern. As mentioned above, we have the "clover" and "bear ears" patterned template. With it mounted in the D1600 jig, I set about crafting my first "clover" Isoloc joint. The first task is to set the template up to match the thickness of the pin board material being used by adjusting it using the scales - 3/4" setting in my case. I milled 7" wide boards for the sake of assuring half-pins on each end of the joint. Next you set your spacer block in the rear clamp and adjust the Isoloc template to drop down and sit flush with the spacer. Next clamp your pin board piece into the front of the jig. Using your socket board piece, you then mark the depth of this board on your pin board face so you can adjust your router bit depth to produce a clean fitting joint. With that all set, ensure the pin for the Isoloc template is in the left "pins" mode hole. This pin allows the template to be slid accross the length of one half pin to mill the socket board accurately in the next step. With everything set, you can proceed to mill your pin board by allowing the guide bush and a 5/16" straight cutter to follow the template pattern. With the pin board, you can rout at full depth on soft woods without too many issues, but if using thicker pieces of material for the sockets (and hence a deeper router bit setting) you may want to take multiple shallower passes if working with hardwoods. For the tests I used soft pine.

Milling the "clover" pattern pins.

When the pin board routing passes are completed, you should have some really nice looking pins routed cleanly and smoothly (if your technique is good). For the record, the first pin board I crafted came out essentially perfect (see photos)

First attempt and perfect "clover" pins!
Doesn't get much easier than that!

With the pin board milled, it's time to craft the sockets to fit the pins. The socket board is mounted horizontally in the top clamp of the jig. It is aligned flush with the face of the pin board (or equivalent dimensioned stock) that you re-mount in the front clamp for this setup purpose. The template is lowered flush onto the face of the socket board and then the template pin is removed, allowing you to slide the isoloc assembly to the left to engage the metal pin into the hole for the "socket" mode. This essentially moves the whole template over to offset it correctly for perfectly aligned sockets.

Now, milling the socket board is a little trickier, particularly if using softwoods or wood that tends to spilt or chip easily. Because you are often cutting with the grain, the chance of a section ripping right off is increased. The manual makes explicit mention of this fact, and to my detriment (of not fully reading the manual first) the first socket board I attempted to mill in the usual left to right router movement across the jig, and at full depth, ended up with problems as shown below...

Eeek! Almost all the sockets had their nice left rounded
edges ripped away completely, as circled here

After consulting the manual, which I should have done in the first place, I discovered that this is noted as a likely and common problem. Instructions are provided to correct this, and basically involve milling the sockets in multiple passes (as opposed to a full depth pass I tried initially) and making the first few passes in a right to left manner instead, with a final pass in the normal left to right way. Of course, after adhering to these instructions, the second socket board attempt came out perfect!

Ahh.. this looks much better. Just a little fine sanding to remove those furry edges...

Moral of the story... read the manual in full first, and don't let your enthusiasm run wild :)
With both pins and sockets now milled, it is just a matter of testing the fit now. I had a sense these would go together just about perfectly, simply by looking at them. The lines were smooth, flowing, but sharp and oozing with accuracy, attributed to the ultra-accurate milling
of the Isoloc template itself. And just as I thought, when fitting the joints together, they joined with almost unbelievable precision...

A dry fit of pins and sockets on the "clover" pattern joint.
I splashed a little mineral turps on the joint to make the joint "pop" out
a little more for ease of viewing.

Needless to say I was thrilled with the result of my first ever Isoloc joint, again reinforcing the fact of how easy it is to craft professional looking joinery with the D1600.

Now, for the "bear ears" pattern. Simply flipping the Isoloc template to the other side offers you the bears ears template. Routing and milling both the pin board and the socket board is done in exactly the same way as the "clover" joint was made, so I wont repeat the steps. Because the process is the same, I was able to craft the bear ears joint in half the time.
From start to end it probably took me about 15 minutes to craft the joint. Of course, it would almost be impossible to craft a complex and curved joint like this by hand, so I can't compare it to a similar hand tool working time, but 15 minutes is time very well spent when you achieve results as good as these...

Milling the pin board for the "bears ears" pattern

First pin board attempt. Again, perfect!

The matching bear ears socket board. With the proper technique, this board
came out perfect first time around.

And the resulting joint... again a dry fit with turps added to highlight the joint.
Note how clean and well fitting the joint is right off the jig.

Imagine opening up a cabinet drawer and discovering these unique looking dovetail joints (can you even call them those?) on a finished piece of furniture. It would sure surprise your visitors, or your customers. It certainly adds flair and a unique design element, one that looks even more attractive than your traditional square lined dovetail joints.

As mentioned, both these joints made above were the result of my first ever use of the Isoloc template on the D1600, adding to the fact of how easy it is to use. And the results speak for themselves. No matter what your level of woodworking skill you could create these joints with little trouble if you are confident with using a router and have a somewhat steady hand.

Variable Guidebush System (VGS)
I was lucky in the fact that I nailed the setting first go for the Variable Guidebush system used in my router to craft the Isoloc joints above. What is the VGS I hear you ask? Essentially it is just a system of guidebushes that instead of having a perfectly straight (vertical) guide surface to run against a template, they have a slightly tapered outer edge that allows you the adjustability needed to fine-tune an Isoloc joint. By moving the VG up or down (by screwing it in further, or out further of its guidebush retainer ring) you can alter the width of pin/sockets ever so slightly to provide a more snug, or a more loose fitting joint.

Rotating the barrel 1/8 of a turn adjusts joint fit by a mere one thousandth of inch. The VGS, which comes standard with each Isoloc template, mounts in many router bases like an ordinary 2 piece screw on template guidebush or by using a Leigh template guidebush adaptor.

If you buy an Isoloc template, the VGS system is included in the Isoloc kit, so you do not have to spend any more to receive and use it with your Isoloc template. As I luckily set the right variable guidebush depth for the joints, I didn't need to alter it, but once you do have it set, you can mark the guidebush itself and its retainer to allow you to accurately re-align the guidebush later on, hence avoiding a repeat of setup and ensuring snug fitting joints first go.

Overall Impression of D1600 + Isoloc Templates
I'm not going to say much here except to simply state that the results speak for themselves.

You know you have a special tool when you can craft virtually perfectly fitting joinery quickly and easily, and with little prior knowledge of this type of complex joinery. I have crafted a few dovetail joints with a hammer and chisel in the past and although they provide a good challenge, they are very time consuming to make, and take a lot of skill to perfect. The D1600 jig + accessories provide the solutions to all those problems, and then some.

I have yet to find a Leigh Dovetail jig owner that is unhappy with their purchase, and I too applaud the design, engineering and development that has gone into this device. If you are serious about making dovetails or the fancier Isoloc-type joinery on your future projects, I would highly recommend this jig. You simply cannot find a better and more versatile dovetail jig on the market today.

Leigh VRS System Accessory Mini-Review
A while after I reviewed the D1600, Leigh came out with the VRS system. VRS stands for Vacuum and Router Support, and it is an accessory that can be used for the D4R, D1600 and the Superjig dovetail jig products. You need to make sure you order the correct VRS version for your dovetail jig as there are slight variations in components required to secure the VRS to your particular jig model. Since I have the D1600, I received the VRS suited to that jig.

The goal of the VRS is two-fold, as suggested by the product's name. It is designed to supply a better vacuum containment system to collect dust and debris during the routing process, as well as to provide additional base support for the router, which previously hung out over thin air on the user side when in operation on the jig.

Attaching the VRS is fairly straightforward. The standard finger assembly guides that came with your Leigh Jig are replaced with new ones that have two additional tapped screw holes to hold the new VRS support bars in place. Just swap the old ones with the new ones. Then you attach the black metal support arms to the finger guides. Now, the main VRS support bar component is made from channeled steel and features strong magnets on the underside. These grab the installed support arms allowing the VRS to basically sit on top of them, held firm by the magnets. The VRS can still be adjusted in/out on the support arms as the magnetic fixing is not permanent and can be adjusted. On the underside of the VRS channel bar is a plastic dust collection hood, that is basically a rolling carriage on small wheels. This slides left and right along the VRS channel to follow your router and ensure the collection hood is always positioned in the router bit cutting area. Two metal control arms are positioned on the vacuum carriage body with a half inch clearance on both sides of the router base. Basically, as you move the router side to side while routing, the base pushes the control arms left or right, which in turn pushes the vacuum collection carriage left or right as well. The mechanics are very simple, but they work perfectly well.

On the underside of the vacuum carriage is an extraction port measuring 1 3/8" OD (1 1/8" ID) to attach a shop vacuum hose onto. Adaptors are provided to allow a larger 2" hose to be attached, or on the smaller side, a reducer cone allowing hoses down to 1" diameter to be attached. Naturally, the hose will move along with the vacuum carriage, so the whole dovetail jig and VRS support needs to be placed where the movement of the dust collection hose will not be impeded.

The second purpose of the VRS is to provide additional router base support. When using the D1600 or other dovetail jigs without the VRS, at least half of the base of the router is unsupported and hanging over the edge of the finger template guides on the jig. This allows greater chance of rocking the router base, which could easily damage your workpiece in the jig, or perhaps even worse, damage your finger template or router bit if they strike! With the VRS added to the dovetail jig, the router base is now supported on both ends, forward and back, and this provides a much safer, and more stable platform to use the jig safely and correctly. And, what's better, after you power down the router, you can just leave it sitting safely supported on the jig and VRS without fear of it falling over or having to remove the router when still under power. It certainly is a handy aid that will enable safer operation, as well as better cutting results.

VRS in use
Correct setup is the key to using the VRS successfully. You must ensure the VRS is sitting at an equal height to the guide finger template so the router base remains perfectly flat against the template guide for good results. The VRS bar is moved in toward the template only allowing enough room for the diameter of the guide bush used with the router bit, plus a little extra for easy maneuvering of the router. When this is done correctly, there is maximum support for the router base, and your dust collection port is as close to the cutting source as possible.

There is no doubt that the extra support for the router makes using the Leigh jig far easier. You do not have to worry so much now about rocking the router and potentially damaging your workpiece or your tools. As for dust extraction, the VRS seems to work somewhat better than the RVA1 accessory that attaches directly to your router. It is also much easier to move the router without the RVA1 attached, using the VRS instead to catch the dust and debris. Of course, no dust collection method is 100% effective, and the VRS will not catch every little bit, but depending on the strength and power of your extraction system, it can collect pretty close to most debris created by the routing process. As a guesstimate, I'd say it collects over 90% fairly easily, evidenced by the distinct lack of dust and debris on the floor near the jig following use, plus almost visually from the lack of finer dust floating in the air after use. Of course, some will be there, and personal dust protection measures should be employed, but the less there is, the better it is for the operator, and anyone else working in the vicinity. The VRS certainly beats using the Leigh jig with no dust collection at all, and if you have the RVA1 attachment, I am sure you will be happier with the VRS, and the added router support it offers is an extra bonus. Well worth grabbing if you use the Leigh jigs often.

VRS Video
Leigh Industries offer a video showing the VRS in action.
You can view that video by clicking on the graphic below:

Leigh D1600 Photos
All photos copyright onlinetoolreviews.com. Use without prior written permission prohibited!

The Leigh D1600 assembled and ready for action!

The finger assembly scales and icons make life easy.

The cam clamps on the top and front clamp rails are simple to use and work perfectly to hold the workpiece securely to the jig.

The real value of the Leigh jigs is their ability to produce variable spaced joints.


The D1600 on its support base, clamped down to the workbench.


One of the best manuals I have come across in a woodworking product. The D1600 manual explains step-by-step how to produce perfectly fitting joints.

 
Routing the tails for a through dovetail joint. Looks good so far.

Dry fitting a through dovetail joint. This was the first joint I made on the D1600 and it came out pretty much perfect! Some small gaps you see in corners where the result of chipout on the pine, which it is very prone to... but a suitable and cheap material for initial jig tests!

Routing tails for a half-blind dovetail joint.

The tails are complete! Notice the black pieces of bridge material inserted between the fingers to run the guide bush against to make proper tail cuts.

Completed tails and pins... it looks like these will go together well...

And they do! Another well-fitting half-blind dovetail joint crafted on the D1600 jig.

RVA1 Router Vacuum Attachment

The collection port on the RVA1 sits below the base and can be adjusted to sit up close to the router bit. It also pivots out of the way to clear obstacles during a cut.

The top side of the RVA1. Note how it attaches to the fence rail clamps on this router. The vacuum hose is attached at the top of the connection tube.

VRS Vacuum and Router Support Accessory