Author Topic: Connecting two rails in parallel for making dados  (Read 2557 times)

0 Members and 1 Guest are viewing this topic.

Offline koze

  • Posts: 11
Connecting two rails in parallel for making dados
« on: February 27, 2019, 07:11 AM »
Hi,

New to FOG, and sorry if this has already been done but search gave me nothing.

I'm making cabinets with full width dados, and I find the process of aligning rails and measuring everything two extra times a bit tedious. Currently using the 1010 and the FS-OF 1000 but I constantly have to move it around for double width dados. I would love to put two FS rails in parallel and have some sort of adjustable spacer between the rails, and the just free hand in the space between. Is this doable, or should I just build a simple wooden jig for this?

Thanks
KS 60 E • OF 1010 EBQ • CTL MIDI I • TS 55 REBQ • PDC 18/4 • FS-SYS/2 • SYS MFT

Festool USA does not pre-approve the contents of this website nor endorse the application or use of any Festool product in any way other than in the manner described in the Festool Instruction Manual. To reduce the risk of serious injury and/or damage to your Festool product, always read, understand and follow all warnings and instructions in your Festool product's Instruction Manual. Although Festool strives for accuracy in the website material, the website may contain inaccuracies. Festool makes no representations about the accuracy, reliability, completeness or timeliness of the material on this website or about the results to be obtained from using the website. Festool and its affiliates cannot be responsible for improper postings or your reliance on the website's material. Your use of any material contained on this website is entirely at your own risk. The content contained on this site is provided for informational purposes only and does not constitute professional advice.


Offline Renovatedspaces

  • Posts: 60
Re: Connecting two rails in parallel for making dados
« Reply #1 on: February 27, 2019, 07:22 AM »
 How wide is the dado you are cutting?
Kapex, CT 26e, Installers clean up kit, RO 125, MFK 700, Domino 500, Carvex 420 with Kit, TS 75

Offline koze

  • Posts: 11
Re: Connecting two rails in parallel for making dados
« Reply #2 on: February 27, 2019, 07:31 AM »
How wide is the dado you are cutting?

It depends: 18 mm or 36 mm. And in terms of length, I'm routing 200-400 mm, and in some cases I'll just line up the sheets and do multiple dados in one cut.
KS 60 E • OF 1010 EBQ • CTL MIDI I • TS 55 REBQ • PDC 18/4 • FS-SYS/2 • SYS MFT

Offline Renovatedspaces

  • Posts: 60
Re: Connecting two rails in parallel for making dados
« Reply #3 on: February 27, 2019, 07:47 AM »
I would go for a Festool MFS or similar. Also you could use a set of parallel guides to easily adjust for the wider cuts. And you could easily move the setup from piece to piece without having to remeasure.
Kapex, CT 26e, Installers clean up kit, RO 125, MFK 700, Domino 500, Carvex 420 with Kit, TS 75

Offline koze

  • Posts: 11
Re: Connecting two rails in parallel for making dados
« Reply #4 on: February 27, 2019, 07:56 AM »
I would go for a Festool MFS or similar. Also you could use a set of parallel guides to easily adjust for the wider cuts. And you could easily move the setup from piece to piece without having to remeasure.

I'm sure the MFS is awesome, but I was hoping to achieve this with something simpler :)
The parallel guides look cool, but I'm not sure how to use them in this case. Could I use them with two rails to create a space in between?
KS 60 E • OF 1010 EBQ • CTL MIDI I • TS 55 REBQ • PDC 18/4 • FS-SYS/2 • SYS MFT

Offline Renovatedspaces

  • Posts: 60
Re: Connecting two rails in parallel for making dados
« Reply #5 on: February 27, 2019, 08:05 AM »
Set the parallel guides to register the first pass with the router. Adjust to move rail by say 18mm
Over to widen the cut. You will need the rail guide for the router.
Kapex, CT 26e, Installers clean up kit, RO 125, MFK 700, Domino 500, Carvex 420 with Kit, TS 75

Offline Renovatedspaces

  • Posts: 60
Re: Connecting two rails in parallel for making dados
« Reply #6 on: February 27, 2019, 08:09 AM »
Does this help?
Kapex, CT 26e, Installers clean up kit, RO 125, MFK 700, Domino 500, Carvex 420 with Kit, TS 75

Offline koze

  • Posts: 11
Re: Connecting two rails in parallel for making dados
« Reply #7 on: February 27, 2019, 08:14 AM »
Set the parallel guides to register the first pass with the router. Adjust to move rail by say 18mm
Over to widen the cut. You will need the rail guide for the router.

Comparing MFS and parallel guides on eBay, the price difference is not that huge. The guides are less and feels a bit more versatile since I can use them for TS cuts too (repeated cuts with TS is also pretty time consuming). As a first step I might just try to build a simple jig holding two rails in parallel and see how far it takes me. Thanks for the input!
KS 60 E • OF 1010 EBQ • CTL MIDI I • TS 55 REBQ • PDC 18/4 • FS-SYS/2 • SYS MFT

Offline koze

  • Posts: 11
Re: Connecting two rails in parallel for making dados
« Reply #8 on: February 27, 2019, 08:15 AM »
Does this help?

This is how I make the cuts today, but constantly readjusting the rail is very time consuming.
KS 60 E • OF 1010 EBQ • CTL MIDI I • TS 55 REBQ • PDC 18/4 • FS-SYS/2 • SYS MFT

Offline koze

  • Posts: 11
Re: Connecting two rails in parallel for making dados
« Reply #9 on: February 27, 2019, 08:40 AM »
So, these are the three options I have so far. One of them being an unknown jig/accessory to attach and align two rails and then free hand between them.

KS 60 E • OF 1010 EBQ • CTL MIDI I • TS 55 REBQ • PDC 18/4 • FS-SYS/2 • SYS MFT

Offline Michael Kellough

  • Posts: 4162
Re: Connecting two rails in parallel for making dados
« Reply #10 on: February 27, 2019, 08:51 AM »
Do you really need to make two adjacent dados? Why not use the MFT?

Offline koze

  • Posts: 11
Re: Connecting two rails in parallel for making dados
« Reply #11 on: February 27, 2019, 08:58 AM »
Do you really need to make two adjacent dados? Why not use the MFT?

The main problem for me is not making adjacent dados, it's making repeated dados and constantly readjust the rails and clamps and having to measure everything again. How could i use MFT for this? Or are you thinking of MFS? It's a bit expensive for my limited need, but I might consider it :)
KS 60 E • OF 1010 EBQ • CTL MIDI I • TS 55 REBQ • PDC 18/4 • FS-SYS/2 • SYS MFT

Offline TSO Products

  • Retailer
  • *
  • Posts: 847
    • TSO Products
Re: Connecting two rails in parallel for making dados
« Reply #12 on: February 27, 2019, 09:00 AM »
@koze  - http://festoolownersgroup.com/other-tools-accessories/new-tso-pg30-parallel-guide/new/?topicseen#newok

look what is shown in video clips on this thread,
NEW TSO TPG-30 Parallel Guide under REPLY # 231:

Simple!

Hans
TSOproducts.com

Home of the GRS-16 and GRS-16 PE  plus TPG Parallel Guide -  the MTR-18 Triangle - TDS-10 Dog Stop and GRC-12 Guide Rail Connector; Work Holding solutions plus AXMINSTER UJK in the USA

Offline Michael Kellough

  • Posts: 4162
Re: Connecting two rails in parallel for making dados
« Reply #13 on: February 27, 2019, 09:19 AM »
Best way to layout/cut dados is by the center of the groove. Ideally you’ll have a bit that does the job in one pass.

You can move a guide rail and whatever other alignment hardware required across the work or you can move the work pieces under the guide rail on the MFT.

In either case you need to find the center of the groove the router will cut. Use the brad point 5mm dowel bit and plunge so the point makes a tiny dot on a scrap work piece. Adjust the router’s guide rail support rods so the offset from the aluminum rail is some easy number to work with like 20mm.

If the parts are small enough to place on the MFT add some kind of registration mark to the MFT that you can align the work piece to (align to center of groove). Drop the rail, add the router, adjust the depth (just for the first cut) and go. Remove router, lift rail, re-position work (or substitute next work piece), lower rail, add router, plow another groove.

If your work is nice and square and you need dodos on opposite ends and you set up the MFT then all you have to do is rotate the panel against a stop. In this case the outrigger foot will need to be set to ride on the MFT.

Offline tomp

  • Posts: 97
Re: Connecting two rails in parallel for making dados
« Reply #14 on: February 27, 2019, 11:52 AM »
I recently had to make a box with a series of cubby holes in it and wanted to dado in the uprights, and came up with this easy, low tech way to get tight fitting dadoes on the undersize thickness plywood that I was using.

I made a T-Square with a leg long enough to span the material being dadoed.


Showing the gusset added to strengthen the joint



The finished assembly



For some reason, I didn't take any photos past this point, but it's use is pretty easy to explain. Not shown in the part is the notch added to align the T-Square with the dado location - I use the Woodpeckers Story Stick to lay out the dadoes on each cabinet side for accuracy, and mark the TOP side of the dado. As I'm using a 1/2" router bit to cut the u/s 3/4" dado in two passes, the alignment notch was made with a strip of 1/2" thick MDF against the guide leg of the T-square, effectively moving the groove 1/2" over from the "normal" position where the edge of the router base runs against the guide. The first pass is then made with the T-square clamped to the part (the gusset makes a very handy clamping point) and the MDF strip against the long leg. After making the first pass, replace the MDF with a strip of plywood from the sheet that was used for the cabinet dividers and, moving in the other direction, make a second pass which opens the dado to an exact fit on the divider.

And, as the OP was asking how to do this using the Festool rail, I came up with this solution using the same basic method - you'l need a rail of the appropriate length, a GRS square with the angle accessory (short one should be OK) and a wood spacer. The base of the router would be guided by the rear (grooved) edge of the rail so that the Festool router adapter is not required. The angle would have to be modified by adding a couple of holes so that the wood can be attached to it. In use, the wood spacer would be attached to the angle and, still using a 1/2" spacer, the alignment notch cut in the wood spacer. At that point, the use is the same as my wooden version - line the notch on the wooden spacer with the layout line on the part, clamp both ends of the rail, put the 1/2" MDF spacer against the back of the rail and cut the 1/2" wide groove, remove the MDF and replace it with the plywood strip and cut the dado to the finished width. The big advantage of this method is that it can be used to cut dadoes of different widths as long as they're wider than 1/2", so that variation of thickness between different brands/batches of plywood doesn't affect it's use.

Actually cutting the dado takes less time than it took me to type out the instructions. I don't have a way to make a demo photo with the GRS square (still waiting for the drill jig to become available so that I can upgrade my early-model GRS) but I could maybe dig out the wooden square and try that. I replaced that method once I figured out how to adapt the EZ Bridge and SSRK to mount on the MFT, and use the stops on the SSRK to give me the end points for the dado - still using the 1/2" MDF and a piece of the plywood being used to set the stops on the SSRK.

Offline Cheese

  • Posts: 6367
Re: Connecting two rails in parallel for making dados
« Reply #15 on: February 27, 2019, 11:53 AM »
Cheapest method:
If you want to space 2 FS rails, why not just cut 2 identical length stop blocks from wood, mark a center point on each of the blocks, align the blocks to your pencil mark for the center line of the dado, slide the rails up to the blocks and use the rail slots underneath the rails to clamp them to your work piece.
See photos below. In this case, I'm using the stop blocks to limit my router travel. However the concept is the same, 2 identical width/length blocks to maintain rail spacing.

More expensive method:
Purchase 4 Festool guide stops, 488752, and some 8mm (5/16") rod stock. Place a guide stop on each end of the FS rail and connect the guide stops with the 8mm rod. Once adjusted to the proper distance it's a simple matter of removing the guide stops, moving the rails, and then replacing the guide stops.

Most expensive method:
This also happens to be my preferred method.  [smile]
Purchase a MFS... [big grin]



« Last Edit: February 27, 2019, 12:05 PM by Cheese »

Offline DynaGlide

  • Posts: 475
Re: Connecting two rails in parallel for making dados
« Reply #16 on: February 27, 2019, 11:56 AM »
I just got a BCTW Kerfmaker in the mail yesterday to help with making dados. Check out https://youtu.be/eFpNxtiSaYY?t=576

If the piece is long enough I envision keeping the router in the same position on the guide rail and using two stops on my MFT fence to move the work piece underneath the rail with the Kerfmaker. Or I have that little guide rod adjuster he uses in the video from my MFK fence. Either way works.

As mentioned above the easiest thing to do is use a bit the exact width of the material and find the centerline but I think in practice this doesn't work out unless you're doing cabinet back panels which can be a little loose.
Instagram @matts.garage

Offline JimH2

  • Posts: 819
Re: Connecting two rails in parallel for making dados
« Reply #17 on: February 27, 2019, 12:02 PM »
Cheapest method:
If you want to space 2 FS rails, why not just cut 2 identical length stop blocks from wood, mark a center point on each of the blocks, align the blocks to your pencil mark for the center line of the dado, slide the rails up to the blocks and use the rail slots underneath the rails to clamp them to your work piece.

More expensive method:
Purchase 4 Festool guide stops, 488752, and some 8mm (5/16") rod stock. Place a guide stop on each end of the FS rail and connect the guide stops with the 8mm rod. Once adjusted to the proper distance it's a simple matter of removing the guide stops, moving the rails, and then replacing the guide stops.

Most expensive method:
This also happens to be my preferred method.  [smile]
Purchase a MFS... [big grin]

or purchase one of these Mafell MF26cc which was my solution. Dado cutter width is adjustable from just over 1/2" to just over an 1". Cutter for 1/2" is being worked on by some other Mafell users. Many of us have asked Mafell to offer a smaller cutter, but it has been to no avail. There is no easier way to cut a dado.

Offline RKA

  • Posts: 1698
Re: Connecting two rails in parallel for making dados
« Reply #18 on: February 27, 2019, 01:46 PM »
Okay, Jim wins for most expensive solution.  Sorry Cheese!

I think Michael is on the right track (no pun intended).  You have two issues you are trying to solve for. 
1.  Setting up your panel and track for multiple dado's in the same location on multiple panels (don't measure and mark, they will all end up slightly off and the likelihood that you make a mistake goes up).
2.  Getting uniform width on dado's that require more than one pass.

For #1, assuming they are all sized similarly, set up a back fence at 90 degrees to your track.  Incra T track works nicely for this, just as long as it's shallower than the piece your are cutting.  Use the flips stops at the appropriate locations for your dado's.  When you finish a dado, flip up the stop and slide the panel down to the next flip stop.  Find a way to fix the track in a consistent 90 degree position in relation to the back fence and stops.  Some dogs and some 20mm holes in a worktop are fine.
https://www.woodpeck.com/drilling/drill-press-tables/woodpeckers-stainless-steel-arm-flip-stop.html

TTrack Plus
https://www.woodpeck.com/incra-tt-scale-track.html

For #2, use a pair of stop collars like the one's below.  Place one on the rod on either side of the router base and loosen the locking nuts on the router base and slide it along the rods to the other stop to make the second half of the cut.  Do some test cuts to get the width just right for your bit and desired dado width.
https://www.amazon.com/uxcell-Internal-Woodworking-Drill-Collar/dp/B00YCDSEVS

This doesn't involve too much of an investment and will give you accurate results.  And you'll always find uses for these parts. 
-Raj

Offline koze

  • Posts: 11
Re: Connecting two rails in parallel for making dados
« Reply #19 on: February 28, 2019, 03:12 AM »
Wow guys, I did not anticipate this much effort in helping me with this. Much appreciated! I will try to experiment with the solutions you present in the thread. TBH I think one issue is my bad work bench, I just moved in to a house and have not had time to build proper shop furniture yet. This makes it much harder to clamp down both rails and panels. I experimented last night with some simple spacers between two rails, but just aligning that setup with clamps, spacers between and under the rails etc took me much longer than just making one cut at a time with the router back up against the high groove side of the rail without any rail guide.

I actually decided to order a set of Festool parallel guides for evaluation, this will help me with repeated track saw cuts primarilly, but I think routing dados will be easier too since I can just slide the whole setup and make dados on multiple narrow panels in one cut. The MFS would have a more limited use case obviously.

Not a huge fan of the router rail guide (hard do get dado depth right, vertical play), but I think it might be my lack of experience that's the issue rather than the hardware :)
KS 60 E • OF 1010 EBQ • CTL MIDI I • TS 55 REBQ • PDC 18/4 • FS-SYS/2 • SYS MFT

Offline rst

  • Posts: 2226
Re: Connecting two rails in parallel for making dados
« Reply #20 on: February 28, 2019, 07:46 AM »
When dadoing with my router, I do not run the router on the rail.  Granted this is awkward on narrow stock but this has not been an issue in my experience.  The fact that the rail sits a few mm higher than the router base has also not been an issue for me.  Sedge's tip on attaching the thin base to the 1400 to make up this difference is something I will use the next time.

Offline Cheese

  • Posts: 6367
Re: Connecting two rails in parallel for making dados
« Reply #21 on: February 28, 2019, 09:38 AM »
Here's another solution that will let you dial in distances on-the-fly.

While the MFS works well for widths that do not change, set & forget...if you have to continually make the width narrower, then wider, the MFS is rather clunky. The MFS can easily be set in .5 mm increments however it usually needs to be removed from the substrate you're working on for ease of adjustment. You then have to be able to accurately re-register the MFS on your previous dadoed groove.

The Micro Fence is really slick for both repetitive width dadoes and also for easily and accurately changing the width of repetitive  dadoes. This way the rail is positioned and clamped down and all adjustments are made to the router carriage assembly. There is no re-registering of the rail.

For the imperial version, it can be adjusted in .001" increments and has a backlash of about .0015". There is also a metric version available that is adjusted in .5 mm increments. I chose the imperial version for it's better resolution. For actual .750" thick ply, if you need .754" you just dial it in and make a cut.

Because of the small amount of backlash, this is capable of extreme accuracy and very repetitive dimensions.

Here are a couple of photos of the Micro Fence in use on Kerdi board. In the 3rd photo check out how even and straight the peak of the 2 chamfers are on the RH piece of Kerdi.

https://microfence.com/product/interface-essentials-package-straight-line-only/








Online waho6o9

  • Posts: 1465
    • Garage Door Handyman.com
Re: Connecting two rails in parallel for making dados
« Reply #22 on: February 28, 2019, 11:48 AM »
Microfence rocks

I like to dado the full sheet and then rip to size when it's feasible.


Offline koze

  • Posts: 11
Re: Connecting two rails in parallel for making dados
« Reply #23 on: February 28, 2019, 02:07 PM »
Here's another solution that will let you dial in distances on-the-fly.

While the MFS works well for widths that do not change, set & forget...if you have to continually make the width narrower, then wider, the MFS is rather clunky. The MFS can easily be set in .5 mm increments however it usually needs to be removed from the substrate you're working on for ease of adjustment. You then have to be able to accurately re-register the MFS on your previous dadoed groove.

The Micro Fence is really slick for both repetitive width dadoes and also for easily and accurately changing the width of repetitive  dadoes. This way the rail is positioned and clamped down and all adjustments are made to the router carriage assembly. There is no re-registering of the rail.

For the imperial version, it can be adjusted in .001" increments and has a backlash of about .0015". There is also a metric version available that is adjusted in .5 mm increments. I chose the imperial version for it's better resolution. For actual .750" thick ply, if you need .754" you just dial it in and make a cut.

Because of the small amount of backlash, this is capable of extreme accuracy and very repetitive dimensions.

Here are a couple of photos of the Micro Fence in use on Kerdi board. In the 3rd photo check out how even and straight the peak of the 2 chamfers are on the RH piece of Kerdi.

https://microfence.com/product/interface-essentials-package-straight-line-only/

(Attachment Link)

(Attachment Link)

(Attachment Link)

(Attachment Link)

That does look amazing, I will definitely check that out. Thanks!
KS 60 E • OF 1010 EBQ • CTL MIDI I • TS 55 REBQ • PDC 18/4 • FS-SYS/2 • SYS MFT

Offline ben_r_

  • Posts: 1206
Re: Connecting two rails in parallel for making dados
« Reply #24 on: February 28, 2019, 05:45 PM »
Another MicroFence user here. That system along with the BCTW KM-1 Kerfmaker is how I cut pretty much all my dados.
If at first you don't succeed, redefine success!

Offline Michael Kellough

  • Posts: 4162
Re: Connecting two rails in parallel for making dados
« Reply #25 on: February 28, 2019, 08:31 PM »
Microfence rocks

I like to dado the full sheet and then rip to size when it's feasible.

I’ve never done this but it seems like an excellent idea.

Offline Sean KS

  • Posts: 109
Re: Connecting two rails in parallel for making dados
« Reply #26 on: March 01, 2019, 01:52 AM »
Ill put in a vote of confidence on micro fence too. Works so well I really don’t know what I’d do without it. Even use it to cut mortise and tenon joints. The owner/inventor/maker/showman Rich is a great to work with and makes really smart tools.

https://microfence.com/product/interface-essentials-package-straight-line-only/

Sean

Offline Bob D.

  • Posts: 1254
Re: Connecting two rails in parallel for making dados
« Reply #27 on: March 01, 2019, 04:21 AM »
Does this help?

This is how I make the cuts today, but constantly readjusting the rail is very time consuming.

Why move the rail? Once it's locked down leave it there and move the router on the rails of the router guide. There is enough adjustment to accommodate your desired dado width. Thinking about this if you had a couple stop collars that fit the FT router guide rails you could set one on each side of the router to set the dado width and slide the router back and forth (left to right) to make repeats cuts at your desired dado width.

For making wide dados I made a jig for my compact router. It rides on a guide bar clamped to the work. I made it with a slot that the router rides in that fits a guide bushing on the router and my version let's me make dados up to just over 1" wide. It has foolproof adjustment using the workpiece to gauge the slot width that the router rides in. Once set its one pass up and another on the return stroke and I'm done, no moving the guide rail or adjustment required at all.

I have a couple photos somewhere (not accessible from this computer)  I will dig up and add to this post. I made it in the spur of the moment with I had on hand when I was building some cabinets and needed to make a bunch of dados that would have been possible but difficult on the table saw. After a couple hours making the jig I sped through making all the dados easy peasy and every one was perfect.

Edit: turns out I can get to those photos from here. :-)

In the third photo is where you see how to set the dado width for the work. By adjusting the screw you can determine how snug of a fit you get. No measuring, just put your work in the gap and adjust the screw, then lock it in using the lock screw (out of view in this photo).

I leave a 1/2" bit in that router and that let's me make up to a 1 inch dado in two passes, but with a larger could go wider though I have yet to need that capacity.

It's worked so well I've never got around to making a more refined version. I took inspiration from a number of dado jigs I saw on the WWW. There are no plans. If you want one figure it out on your own as I did. There is more than enough information in these photos and on the web to put your own together in about an hour.
« Last Edit: March 01, 2019, 04:40 AM by Bob D. »
-----
It's a table saw, do you know where your fingers are?

Offline koze

  • Posts: 11
Re: Connecting two rails in parallel for making dados
« Reply #28 on: March 01, 2019, 06:50 AM »
Ill put in a vote of confidence on micro fence too. Works so well I really don’t know what I’d do without it. Even use it to cut mortise and tenon joints. The owner/inventor/maker/showman Rich is a great to work with and makes really smart tools.

https://microfence.com/product/interface-essentials-package-straight-line-only/

Sean

What I don't get is how it's better than the less costly Festool FS-OF (apart from the fact that FS-OF seems incompatible with 1010)?
KS 60 E • OF 1010 EBQ • CTL MIDI I • TS 55 REBQ • PDC 18/4 • FS-SYS/2 • SYS MFT

Offline koze

  • Posts: 11
Re: Connecting two rails in parallel for making dados
« Reply #29 on: March 01, 2019, 06:50 AM »
Does this help?

This is how I make the cuts today, but constantly readjusting the rail is very time consuming.

Why move the rail? Once it's locked down leave it there and move the router on the rails of the router guide. There is enough adjustment to accommodate your desired dado width. Thinking about this if you had a couple stop collars that fit the FT router guide rails you could set one on each side of the router to set the dado width and slide the router back and forth (left to right) to make repeats cuts at your desired dado width.

For making wide dados I made a jig for my compact router. It rides on a guide bar clamped to the work. I made it with a slot that the router rides in that fits a guide bushing on the router and my version let's me make dados up to just over 1" wide. It has foolproof adjustment using the workpiece to gauge the slot width that the router rides in. Once set its one pass up and another on the return stroke and I'm done, no moving the guide rail or adjustment required at all.

I have a couple photos somewhere (not accessible from this computer)  I will dig up and add to this post. I made it in the spur of the moment with I had on hand when I was building some cabinets and needed to make a bunch of dados that would have been possible but difficult on the table saw. After a couple hours making the jig I sped through making all the dados easy peasy and every one was perfect.

Edit: turns out I can get to those photos from here. :-)

In the third photo is where you see how to set the dado width for the work. By adjusting the screw you can determine how snug of a fit you get. No measuring, just put your work in the gap and adjust the screw, then lock it in using the lock screw (out of view in this photo).

I leave a 1/2" bit in that router and that let's me make up to a 1 inch dado in two passes, but with a larger could go wider though I have yet to need that capacity.

It's worked so well I've never got around to making a more refined version. I took inspiration from a number of dado jigs I saw on the WWW. There are no plans. If you want one figure it out on your own as I did. There is more than enough information in these photos and on the web to put your own together in about an hour.

Very clever and pragmatic, I like it!
KS 60 E • OF 1010 EBQ • CTL MIDI I • TS 55 REBQ • PDC 18/4 • FS-SYS/2 • SYS MFT