GRS-16 Track Saw Guide Rail Square Review


The GRS-16 being used to cross cut cabinet parts

Track saws are very versatile and accurate tools for making precise cuts in a variety of materials.  There are a variety of accessories available that add to the accuracy and capability of a track saw, and the GRS-16 guide rail square is one of those accessories.  In this review I will go through the design and features of the GRS-16's, explain how they work and I also share my real world experience with them as a professional cabinet maker after putting them to work in my shop.

There are two different models of the GRS-16 available.  One is the regular GRS-16 and the other is the GRS-16 PE (PE stands for parallel edge).  Both of these models are designed and made by TSO Products.  I will explain the difference between the two models and which applications each excels at as we go.  TSO was good enough to send both of these models to me to put to work in my shop and review, so a big thanks to them for that.  Be sure to watch my full video review at the bottom to see the GRS-16 in action and also leave your comments or questions in the comments box below that.


Both models of the GRS-16

Track clamp being used

Both models are made of CNC machined aluminum, so they are very accurate and durable.  The basic design consists of a 15 3/4" long reference edge that registers to your work piece and then another reference edge that is machined exactly 90 degrees to the first edge.  This second reference edge is what your track saw guide rail registers against.  The attachment method is quick and easy with no fussing.  A T-channel is machined in the top of the square which simply slides into the T-slot on the underside of your guide rail.  A draw clamp with a hooked end then hooks onto the lip of the guide rail edge and pulls everything tight and locks the square in place.  To see this process in action, check out my review video at the bottom of the article.

GRS-16 stored in L-Boxx3

I appreciate the fact that there is no loose hardware to keep track of with this design and no extra tools required to install the square.  Another great feature of the GRS-16's are the notch that allows a guide rail clamp to be used in conjunction with the square.  The bar of the clamp nests into this notch so that the ability to use clamps is not lost when using the GRS-16's.  The overall size of either GRS-16 model is small enough that I can easily store one inside the L-Boxx3 that I keep my track saw and all of its accessories in.  This is a huge advantage since it takes up no extra space when I'm travelling to site.  For Festool users, the GRS-16's will also fit in a Systainer 1 laying flat.


Single edge GRS-16

The GRS-16 is the single edge model which has one reference edge that contacts the work piece.  This model is best suited to working with sheet goods where you have the option of using either edge of your work piece to reference.  I found that the slimmer overall profile of the regular GRS-16 model was a little bit easier to work with for the majority of cuts and I found myself using this model the most for general cuts.


GRS-16 PE (parallel edge)

GRS-16 PE countertop cut

The GRS-16 PE is the parallel edge model which has two reference edges instead of one.  The advantage with this model is you can reference either the front or back edge of the work piece depending on the situation.  This ability comes in handy when you are working with materials that have the back edge trued up but not the front edge, or if you are cross cutting countertop without backsplash.  In the countertop scenario, the GRS-16 PE can reference the back edge which is square rather than trying to reference a rolled edge on the front, so you get a more accurate cut.  I used the PE model recently for cutting some countertop and it worked great for that application.  Being able to reference either the front or back edge also gives flexibility as to which direction you cut, and with a track saw that makes a difference since you want your 'keeper' piece to be on the same side as the guide rail.


Installing the GRS-16

The process to install either model of the GRS-16 is quick and easy.  You start with your guide rail sitting on your work surface and overhanging a bit at the end.  The T-channel simply slides into the T-slot on the underside of your guide rail and slides along until it's in the desired position.  You then hook the end of the clamp onto the lip on the edge of the guide rail and draw the clamp down to pull everything tight and lock the GRS-16 in place.  TSO claims that it is a 5 second install process, and I found that to be true.  The connection that the GRS-16 makes is solid and secure.  I never had any worries about it being knocked out of alignment or moving since the guide rail solidly registers to that machined reference edge and the clamp doesn't let anything move.  Both GRS-16 models are compatible with Makita, Festool or Triton guide rails.  To see the installation process in action, watch my review video at the bottom of the article.


Checking the GRS-16 for square

So it's all well and good if this square is quick and easy to use, but if it's not accurate then it just becomes a snazzy looking paper weight.  Accuracy was the first question in my mind when I got the GRS-16's and it was the first thing I checked.  I installed the GRS-16's and checked them against the guide rail with my engineer's square.  Both models were bang on square which I was very pleased to see.  I'll talk about how that accuracy translates into real world cuts in just a minute.  One of my first impressions of the GRS-16 was that it seemed to have a fairly short reference edge when looking at it installed on a guide rail.  I then realized though that the part of the GRS-16 that goes under the guide rail is also included in the reference length since that reference edge continues under the guide rail.  So the total reference length is 15 3/4" on both models which seems to be enough to give very accurate results. 

In Action

The GRS-16 in use on the MPT

So now for what it really all comes down to, and that is how do they perform in real world cuts.  I've put both models to use in my shop over the past couple months and I've been very impressed with how they perform.  The bulk of the work I've been doing with them is cutting cabinet backs to length.  Most of the rips for cabinet backs are too wide to fit on my table saw cross cut sled and are also too wide to fit between the Parf dogs on my Multi Purpose Table (MPT).  The GRS-16 allowed me to make quick, easy and accurate cuts on these wider cabinet parts that would have otherwise been a pain to deal with.  I set up the full 8' rips on the sacrificial strips on my MPT and was able to quickly cut all my parts to size.  I checked each piece after I cut it with both a square and measuring corner to corner and they were bang on which is what I like to see.  Really, the limiting factors for accuracy in this case are: how accurate your guide rail is for straightness, and how straight the edge of your work piece is.  If both of those are accurate then your cuts should be bang on square.

The method that I found works best for positioning the guide rail to my cut mark when using the GRS-16 is to press down on the GRS-16 which tips the guide rail back off the grip strips.  It's then easy to slide the guide rail along the work piece until the splinter strip lines up with the cut mark and then let it drop back down.  I give a little push on the GRS-16 to ensure it's making full contact with the edge of the work piece and then I'm ready to make the cut.  I also found that the GRS-16 makes a great place to hold onto while making the cut to ensure everything stays where it's supposed to.  Again, this method is demonstrated in the video review.

Which Model to Get?

Both GRS-16 models being used together

If you're wondering which model is the best to get, that really depends on the work that you do.  If you are mainly breaking down sheet goods and usually have two good reference edges to choose from, then the regular GRS-16 model should work great for you.  Like I mentioned earlier, I do like the smaller form factor of the regular GRS-16 and it is also a little cheaper.  If you do a lot of countertop work or regularly work with materials that only have one good reference edge, then the GRS-16 PE may be better for you.  The PE model gives maximum versatility with only a slight increase in overall size.  If you can afford both models you can also use them both together.  The GRS-16 can be installed at the front of the guide rail and the GRS-16 PE can be installed at the back with the distance between them matching the work piece width.  This setup is useful for making exceptionally long cuts where you want to ensure you are square to both edges of the material.  Personally, I haven't come across a need to use them like this yet but it is an option if you need it.

DP Tool Score

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Quality - 5/5

For quality I give 5/5 stars.  The build quality and machining are excellent and they feel solid and durable.  I don't feel like I have to baby them and they should stay accurate for years to come.

Performance - 5/5

For performance I give 5/5 stars.  The GRS-16's let me make very accurate cuts quickly and easily.  There is no fussing with anything, they do what they are supposed to do and do it well.

Design - 5/5

For design I give 5/5 stars.  They are well thought out with no loose hardware to contend with and integrate well with the guide rails with no modifications required.  The GRS-16's are easy to install and work with.

Value - 5/5

For value I give 5/5 stars as well.  They aren't inexpensive but I think you definitely get what you pay for in this case.  In my opinion, the speed, accuracy, and ease of use are worth the investment.

Overall DP Tool Score - 5/5


So that's my take on both models of the GRS-16.  As I mentioned earlier, TSO Products did send these to me to review but they did not pay me to do the review and I'm not associated with them so my review is just my honest thoughts and experiences based on my use of them.  The fact that I didn't have anything negative to say about them is simply because I couldn't find anything that I didn't like, they really do work that well.  So with an overall DP Tool Score of 5/5 stars, I would highly recommend either model if you are in the market for a guide rail square.

To see the GRS-16's in action, make sure you also watch my full video review below.  Please leave any questions or comments you have in the comments box at the bottom of this page.  For more information or to purchase a GRS-16, you can visit TSO Products at

Watch my review video of the GRS-16 and GRS-16 PE and see them in action!


Dan Pattison

My name is Dan Pattison and I am a self-employed builder and designer from Halifax, Nova Scotia, Canada.  The majority of my local work consists of custom kitchens, built-in cabinetry, trim work and finish carpentry.  I enjoy the design and build process and the satisfaction that comes from building things with my hands.

My interest in woodworking was sparked by a junior high woodworking class where I was fascinated by the band saw. I was determined to get my own band saw and started my own small woodshop in my parent's basement. My skills and tool collection grew from there and has brought me to where I am today.

I am always trying to come up with better and more efficient ways to work.  My Multi Purpose Table (MPT) design came from my desire for a more efficient way to work along with being able to build it myself rather than buying something commercially made.  A result of the Imagine-Design-Build process.

I enjoy sharing my ideas with others through digital media. My YouTube show 'DP Shop Talk' was created for that purpose and focuses on shop made efficiency solutions. I have a passion for the work I do and I hope I can pass that passion on to others as well.