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View Full Version : Building a MFT: Part Two - making a rail hinge



Derek Cohen
12-27-2022, 11:17 AM
In the first segment of the MFT build, the aim was to construct a bench top that would accept the Festool accessories for work holding. The MFT would serve for routing, sanding, carving, and as an outfeed for a jointer, slider and router table.

The 20mm holes were routed using a CNC-made template.

https://i.postimg.cc/hK9jr8h0/17.jpg

https://i.postimg.cc/MxXnvc4r/16.jpg

It needs to be understood that the reason for making the MFT was partly due the cost of purchasing one in Australia being excessively expensive (the Festool MFT sells for $1595), particularly so when I am not sure how much use it will get.

A large part of this cost lies in the rail hinge and rail fence, since a typical use of a MFT is for sawing ...

https://i.postimg.cc/NB2LyvcS/Festool-MFT2.jpg

The stability and ease of adjustment of Festool rail hinge has come in for some criticism ...

https://i.postimg.cc/6Bsqnb63/Festool.jpg

... which has lead to aftermarket versions becoming available, such as this Dashboard hinge ...

https://i.postimg.cc/6w38XG19/Dashboard.jpg

This looks a beautiful piece of equipment, camera-level precise ... but it would cost around $700 landed in Oz.

So I decided to build my own. Two considerations - design and materials. The design is a mix of ideas, some taken from other builds on the Internet, Peter Millard's hinge design ..



.. and a few of my own. Fabricating in metal was not feasible as I do not have the tools to work it. Using ply wood, MDF and even hardwood was rejected as these are not durable enough. In the end I settled on nylon cutting boards - cheap and very hard wearing.

https://i.postimg.cc/SSmmVHHS/1.jpg

The nylon cannot be glued, and so all bolt holes were tapped for threads, and screwed together ...

https://i.postimg.cc/dsnwf4K8/2.jpg

The dimension across the top is 8" and the height is 5 1/2".

This holder is used for both the hinge side (where the rail is connected) and the pin side (where the rail is squared to the table) ...

https://i.postimg.cc/SknkZ61M/3.jpg

Two key factors are present: each part is built with care for precision - errors are additive and will affect accuracy. Part of this is that the hinge must not have any play.

https://i.postimg.cc/LRCmBCDS/4.jpg

https://i.postimg.cc/G32dnGc6/5.jpg

The rail hinge is set at a height below the bench top when not in use.

The two knobs (above right) tighten the connector to the rail ...

https://i.postimg.cc/z5XJhZnp/6.jpg

The rail connector has rebates to fit the rail ...

https://i.postimg.cc/bp484Z4F/7.jpg

The pin in the pin holder is square and sized for a tight slip fit ...

https://i.postimg.cc/bqb8PzhY/8.jpg

Derek Cohen
12-27-2022, 11:17 AM
All together - the rail swings over ....

https://i.postimg.cc/KZD2KJjd/10.jpg

... and rests on the pin ...

https://i.postimg.cc/qkTrM9Js/9.jpg

The rail is able to be lifted up out of the way in readiness to position a board ..

https://i.postimg.cc/Jr7WjZBt/11.jpg

All feels rock solid.

Checks for square against a rear fence ...

https://i.postimg.cc/05bRBvns/12.jpg

... and against the front of the bench (the ends are exactly parallel and all the holes are square) ...

https://i.postimg.cc/L9yFD5zD/13.jpg

Lastly, a stop is added to both hinge and pin holders, to allow exact re-positioning ...

https://i.postimg.cc/hnMX60sy/14.jpg

All the best for the festive season.

Regards from Perth

Derek

Jim Becker
12-27-2022, 1:00 PM
Brilliant!

Derek Cohen
12-29-2022, 9:50 AM
One EDIT: since building, the pin has been moved over to the left side of the pin holder. This is to increase/maximise the support the rail receives.

Regards from Perth

Derek

Keegan Shields
12-29-2022, 3:07 PM
Nice work Derek! I never thought about using nylon - much nicer to machine than aluminum or steel.

For those following along, another possibility are the Parf/UJK track attachments that clip into the tall bench dogs, which is what I use. Works great.

Here’s the system in action:
https://youtu.be/QxIkut7-nl4

Here are the rail clips:
https://tsoproducts.com/accessories/ujk-dog-rail-clips/

Works great for 90 deg cuts, routing square dados, etc as long at the hole grid is laid out perfectly. I’ve had good luck with the Parf guide system. I wouldn’t recommend the WP version.

Derek Cohen
12-29-2022, 8:12 PM
Keegan, an alternative to the TSO rail clips are David Stanton’s Dog Locks. I have a set, but have only used them a few times so far.

https://m.youtube.com/watch?v=hXsX8rErc50

Regards from Perth

Derek