# Secret Soss: A simple Soss hinge jig



## newTim (Jul 11, 2008)

*Just add Soss*

In two recent projects, the Copper Patina box and the String Box II, I installed Soss hinges. I had once thought of a way to adapt a regular square hinge jig to make routing the mortises for the Soss hinge easier. It turns out, with this jig, it is very easy, and fast, and accurate. The Secrets of the String Box Revealed blog showed some photos of the jig and described how it works. I'm sure most folks on LJs could see how this was built, but I thought I'd do a more detailed blog to show how. So let's start at my favorite part, the end.

Here's what we'd like to achieve, tight fitting hinges that are aligned so that the box and lid are square and flush. The Soss hinge requires eight mortises, four narrow, deep, inside, and four wider, shallow, outside. While the outside or top mortises ideally need to be tight to the hinge, the inside or bottom mortises can be a little larger to provide easier installation. But not so wide that it interferes with the screw holes.



















Let's start by considering the required dimensions of each mortise. The table below shows the mortise size and (my) template groove sizes for the Soss 101 (3/8") and 203 (1/2") hinges. Since my templates use a 5/8" guide bushing, just add the difference between the diameter of the bit (i.e. the width of the hinge) and the bushing to the mortise size to figure the template hole size. For example, the Soss 203 hinge requires a top mortise 1 3/4" long and 1/2" wide. Using a 1/2" diameter bit and a 5/8" bushing the difference is 1/8" (i.e. 1/16" on each end), so the template's guide hole needs to be 1 7/8" long or the 1 3/4" mortise plus 1/8". There are plenty of sites on the net including Woodcraft, Rockler, etc., that have the dimensions for the hinge you're using. Just use this table as a concept guide and make the appropriate calculations.



















Now that we finished the end, next time we can begin the finish.


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## Ecocandle (Jan 2, 2010)

newTim said:


> *Just add Soss*
> 
> In two recent projects, the Copper Patina box and the String Box II, I installed Soss hinges. I had once thought of a way to adapt a regular square hinge jig to make routing the mortises for the Soss hinge easier. It turns out, with this jig, it is very easy, and fast, and accurate. The Secrets of the String Box Revealed blog showed some photos of the jig and described how it works. I'm sure most folks on LJs could see how this was built, but I thought I'd do a more detailed blog to show how. So let's start at my favorite part, the end.
> 
> ...


That was a great post! I was just wondering about how to do this yesterday. The box you made is fantastic. Very nicely done.

I think I will have to pick a project which will let me try this out. You have inspired me.


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## Sawdust2 (Mar 18, 2007)

newTim said:


> *Just add Soss*
> 
> In two recent projects, the Copper Patina box and the String Box II, I installed Soss hinges. I had once thought of a way to adapt a regular square hinge jig to make routing the mortises for the Soss hinge easier. It turns out, with this jig, it is very easy, and fast, and accurate. The Secrets of the String Box Revealed blog showed some photos of the jig and described how it works. I'm sure most folks on LJs could see how this was built, but I thought I'd do a more detailed blog to show how. So let's start at my favorite part, the end.
> 
> ...


Thanks. I had made a jig for my Soss hinges but it was, I now see, too small and that's probably why it did not work right.
Favorited this until I can make the jig correctly.

Lee


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## newTim (Jul 11, 2008)

newTim said:


> *Just add Soss*
> 
> In two recent projects, the Copper Patina box and the String Box II, I installed Soss hinges. I had once thought of a way to adapt a regular square hinge jig to make routing the mortises for the Soss hinge easier. It turns out, with this jig, it is very easy, and fast, and accurate. The Secrets of the String Box Revealed blog showed some photos of the jig and described how it works. I'm sure most folks on LJs could see how this was built, but I thought I'd do a more detailed blog to show how. So let's start at my favorite part, the end.
> 
> ...


Thanks. I'll post more details tonight. It got late last night. Sawdust… I don't know if this is the correct way to do it, but it sure works. Takes a little time to build the jig, but once you do it should last a long time.


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## RjGall (Jun 16, 2008)

newTim said:


> *Just add Soss*
> 
> In two recent projects, the Copper Patina box and the String Box II, I installed Soss hinges. I had once thought of a way to adapt a regular square hinge jig to make routing the mortises for the Soss hinge easier. It turns out, with this jig, it is very easy, and fast, and accurate. The Secrets of the String Box Revealed blog showed some photos of the jig and described how it works. I'm sure most folks on LJs could see how this was built, but I thought I'd do a more detailed blog to show how. So let's start at my favorite part, the end.
> 
> ...


I Love the box!! I also really like the blog you did….Thanks for posting it!


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## newTim (Jul 11, 2008)

*Let's Roll*

Well let's get this thing going. The object is to make a rectangular hole in the middle of a board. Two boards actually; one for the top mortise and one for the bottom. Start by getting the measurement of the diameter of your router base. We need to make the jig wide enough so the base doesn't bump into the hinges. As you will see later, you can mortise the hinges into the jig to make a flat surface, however, this would take time and risk the two boards being slightly out of alignment which will throw off the final result. Just seems easier to make it wide enough for the base. You'll see what I mean.









I made mine 4" wide. You will need four pieces identical in size. I use 1/2" plywood which is strong enough for the router yet shallow enough for the bit to reach the mortise. (Note: pictured here is 3/4" ply which I used before discovering that the bit would not reach the bottom of the mortise).








Use a scrap piece to dial in the blade height. Here I'm using a 5/8" guide bushing so the blade needs to be raised just 5/16".








Check the chart on the previous blog or the specs that come with the hinges to determine the exact length of the hole. To center the hole use a fence to register each side and make matching cuts the distance from the edge that is required to form the outsides of the hole. Then plow out the middle of each cut.


























Now is a good time to clean up the cuts and mark centerlines. Be careful not to remove too much material as you've invested a lot of time already to get a precision mortise. You can fine tune the opening later. Next glue up the matching pairs making sure the pieces are flat and the sides are flush.

















You want to end up with parts that look like these.









This gripping tale to be continued…


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## RjGall (Jun 16, 2008)

newTim said:


> *Let's Roll*
> 
> Well let's get this thing going. The object is to make a rectangular hole in the middle of a board. Two boards actually; one for the top mortise and one for the bottom. Start by getting the measurement of the diameter of your router base. We need to make the jig wide enough so the base doesn't bump into the hinges. As you will see later, you can mortise the hinges into the jig to make a flat surface, however, this would take time and risk the two boards being slightly out of alignment which will throw off the final result. Just seems easier to make it wide enough for the base. You'll see what I mean.
> 
> ...


Thanks Tim for walking us through the process …this will come in handy !


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## newTim (Jul 11, 2008)

*Steps to success*

Like most things it takes much longer to explain a process than it does to complete. Still, there are a lot of steps involved, and while you can sometimes change to order chances are there are no shortcuts, especially when precision is the final goal. Well enough philosophy, how 'bout we just do woodworking. At this point the jig is maybe a half hour from being functional.

Here I trimmed one side of each template to about 1 3/4" from the centerline of the mortise. You may wish to also trim the other side, but for this setup, since the knuckle of the hinges will rise above the surface you need the room so the router does not bump into them (see step one of this blog). Of course you can get around this by simply mortising the hinges into the templates. This requires a little more work and requires a precise alignment so the mortises line up. It seems to be just as easy to leave the template's wide and apply the hinges as you'll see below.









Next we raise the blade to cut a little higher than the centerline of the mortise to create a channel through which we can attach a fence to register the mortise against the back of the box.









You only need to make these cuts on the wide (top mortise). Remember, we cut the top (the wide and shallow) mortise first, then the narrow, deep bottom mortise.








Then head over to the router table and cut some dados, grooves, channels, whatever, deep enough so the head of the screws holding the fence do not interfere with the router.








Now comes the payoff pitch. The two templates are self registering. Since they are the same height and width, you simply pair them up and attach hinges to the end. The only thing you have to watch for is that the side you just cut on the router is on the inside.


















Next time we'll get a very precise alignment of the fence, do some test cuts, and finish the series. Hope this helps.


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## newTim (Jul 11, 2008)

*Adding a precision fence: ready to use*

The fence sits underneath the templates and is used to register the jig against the back of the box and securely clamp the jig to the box. The Soss 203 requires a 1/8" space between the back of the hinge and the back of the box. Since the hinge is 1/2", the centerline of the hinge must be 3/8" from the back. It is important that the fence be square to the template otherwise the hinges, hence the box lid, will be crooked. I cut a piece of 3/4" plywood about the width of the templates, drilled through holes, and inserted threaded nuts. Here's how I set the fence.

I clamped a piece of scrap wood in the bench clamp and used a 3/8" brass bar to mark the centerline of the hinge on the bench.










Then I lined up the centerline of the jig to that line and used the clamp to gently press the jig's fence against the bench before tightening the bolts that hold the fence in place. You don't want to tighten the clamp too much. Just enough to press the fence against the bench. And that's it. The fence is perfectly fitted to the jig.








I place the scrap wood back into the clamp, drew a centeline across the piece, and clampled the jig in place.










To make the first mortise cut, which is the top mortise for the hinge, you zero out the bit onto the surface of the part being cut and use the hinge itself to set the router's depth gauge. I like to use long bits for mortises, but I think a regular length bit should still work. I like to first make a series of plunge cuts then clean out the waste.










After the first cut I vacuum out the mortise and flip the other half of the jig in place to cut the second mortise.










Same procedure as before. I first zero out the bit then I use a scrap piece to set the depth gauge. Note, in this step I am zeroing out the bit into the bottom of the first mortise so I only have to cut another 1/2" plus a shade deeper (IOWs, the total hinge depth is 3/4", 1/4" top mortise and another 1/2" for the bottom).










And here's the result in the scrap piece with no adjustments. Note, particle board like plywood is much softer than most of the hardwoods we use so a hinge which may have a snug fit in the scrap wood may be slightly too big in the actual hardwood. The jig is easy to adjust with a file and sandpaper. If the mortise is too big you can apply tape to the ends as a shim.




























I hope this series has been beneficial. If you have any comments or suggestions on the blog or improvements for the jig please let me know.


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## RjGall (Jun 16, 2008)

newTim said:


> *Adding a precision fence: ready to use*
> 
> The fence sits underneath the templates and is used to register the jig against the back of the box and securely clamp the jig to the box. The Soss 203 requires a 1/8" space between the back of the hinge and the back of the box. Since the hinge is 1/2", the centerline of the hinge must be 3/8" from the back. It is important that the fence be square to the template otherwise the hinges, hence the box lid, will be crooked. I cut a piece of 3/4" plywood about the width of the templates, drilled through holes, and inserted threaded nuts. Here's how I set the fence.
> 
> ...


Tim Thanks for putting together this blog it will come in handy!


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## Dennisgrosen (Nov 14, 2009)

newTim said:


> *Adding a precision fence: ready to use*
> 
> The fence sits underneath the templates and is used to register the jig against the back of the box and securely clamp the jig to the box. The Soss 203 requires a 1/8" space between the back of the hinge and the back of the box. Since the hinge is 1/2", the centerline of the hinge must be 3/8" from the back. It is important that the fence be square to the template otherwise the hinges, hence the box lid, will be crooked. I cut a piece of 3/4" plywood about the width of the templates, drilled through holes, and inserted threaded nuts. Here's how I set the fence.
> 
> ...


thank´s for the toturial
looking forward to lern more from you

take care
Dennis


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## Wyo7200 (Feb 20, 2014)

newTim said:


> *Adding a precision fence: ready to use*
> 
> The fence sits underneath the templates and is used to register the jig against the back of the box and securely clamp the jig to the box. The Soss 203 requires a 1/8" space between the back of the hinge and the back of the box. Since the hinge is 1/2", the centerline of the hinge must be 3/8" from the back. It is important that the fence be square to the template otherwise the hinges, hence the box lid, will be crooked. I cut a piece of 3/4" plywood about the width of the templates, drilled through holes, and inserted threaded nuts. Here's how I set the fence.
> 
> ...


Awesome. Thank you for doing the write up!


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## Wyo7200 (Feb 20, 2014)

newTim said:


> *Adding a precision fence: ready to use*
> 
> The fence sits underneath the templates and is used to register the jig against the back of the box and securely clamp the jig to the box. The Soss 203 requires a 1/8" space between the back of the hinge and the back of the box. Since the hinge is 1/2", the centerline of the hinge must be 3/8" from the back. It is important that the fence be square to the template otherwise the hinges, hence the box lid, will be crooked. I cut a piece of 3/4" plywood about the width of the templates, drilled through holes, and inserted threaded nuts. Here's how I set the fence.
> 
> ...


Thanks again for the series! Worked perfectly with your jig and now I have to wait for the black hinges to arrive.

I used a 3" long carbide bit and it barely had enough clearance at the 5/8's guide to cut out the bottom. I ordered a longer 4" milling bit for future soss'ing.


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