MFT and Rail Square - my thoughts

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Molynoox

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As a novice who has just dived into the world of MFT, I thought it might be interesting for me to share my experiences with my first go at it. It's my first attempt at building and using an MFT and a rail square. I wish I knew at the start what I now know and perhaps I can save others a bit of time if they are on the same trajectory and also thinking about investing in an MFT setup.

I have spent about 4 or 5 weekends with the setup, making workshop cabinets/benches. I have a sort of 'build thread' on it so won't go into any more detail.

What can it do
  • It makes square cuts, quickly and accurately
  • With some accessories it can also eliminate the need for marking up
  • It can help you assemble things square
  • Note: making >200mm cuts needs a different method to <200mm cuts (see below for more on this) but both can be done

For context, here is my current setup:
IMG_20230325_182642.jpg


Here is my setup before I built my benches:
IMG_20230205_122116.jpg


Important note on my setup
I do NOT have a hinge for my rail. I am reliant on using the dogs to align the rail and the workpiece at 90 degrees to one another. Many of the constraints listed below are specific to my setup and could perhaps be solved (or reduced) with a hinged rail.

What can't it do (without a hinged rail)
  • A standard 718mm deep MFT cannot be used to cut anything wider than about 550mm as you need a long dog at top and bottom of workpiece (to support the rail) which reduces the usable width of the table by about 150mm
  • In my experience that is quite a restriction for the stuff I am building as pretty much every cut is wider than 500mm.
  • You CAN use the table lengthways, but then you would need an extra table for support (I do have an extra table but only after I built my second unit).
  • Anyway, it was all a bit chicken and egg for me as I needed the MFT to make the cuts and I needed to make the cuts to build the MFT (and all my other units)
  • Once I had the MFT bench and another bench of the same height I found that I could achieve pretty much any MFT type task....
  • BUT, up until that point I was having to use my sawhorses as a temporary workstation (I used two long (2.5m) lengths of 4x2 stretched across my sawhorses with a sheet of plywood on top)
  • It would be good to have an MFT table that was 2.7 x 1.5m, and then you wouldn't need a rail square, but that is too big for most workshops I imagine
  • Fortunately I had a rail square from the start (which I bought at the same time as my MFT top) and this allowed me to work on the large sheets and make large cuts
  • Yes I could have just marked the sheet up at top and bottom and lined up the track with my pencil marks but I am aiming for speed and accuracy as for me that is the whole point of the MFT. If I start messing around making marks all over my workpiece and lining up the rail its not so big an upgrade over a standard track saw setup. IMO

Rail square
  • The Benchdogs square I bought is definitely a nice piece of equipment - I know it's expensive but it works. It comes with a little calibration report showing the measured accuracy on all dimensions and the accuracy appears to be plenty good enough for making cabinets (but perhaps not quite up to scratch for space telescopes)
  • I also bought the 'fence+tape+stop' thing that attaches to the square (I think it was about £60) which can be used to rapidly set your chosen cut length and simply line up the square and it will cut at the exact right length
  • I created a 200mm calibration block so that I could fix the rail square to the fence in the right place every time I use it. It would be better to have a longer calibration block I think because when I calibrate mine to the 200 block it is slightly off at 600mm (less than a mm but even so I would like it to be spot on without extra tuning)
  • In practice I tend to just leave the square attached to one of my rails and keep the other rail for cuts without the rail. I have two 1.5m rails
  • In use the rail square is quite the dream - simply set the little blue slider to your width, turn the screw to lock it and away you go. Just line up the rail and make your cut and you have a perfectly square and accurate cut with almost zero setup time.
  • It's actually quite liberating to be able to get cuts that accurate and repeatable with so little effort, no measuring, no marking, just move the little slider and go.
  • If you are making multiple cuts of the same size its super rapid.
My calibration block:
IMG_20230326_173026.jpg

200mm block in use to set the fence to exactly 200mm:
IMG_20230326_173222.jpg


once calibrated you don't need the block anymore you just move the little blue slider to the lengths you want

Thin cuts
  • If you are cutting a width of more than 200mm, then the rail square works really well. In this case you are measuring to the left of the rail using the etched measurements on the fence. The fence goes up to about 650mm with one part of the fence and if you want more you can add the second bit of fence which will get you to about 1.1m. I never actually tried cutting anything longer than 600mm so haven't tried attaching the extra fence extension yet.
  • If you want to cut something which is less than 200mm then you are going to have to get creative.
  • The method I used was to setup a 'stop block' - a piece of timber clamped down at the right place so you can push your workpiece up to it and guarantee the right length of cut
  • Now your focus shifts to the right side of the rail.
  • Basically the rail is about 200mm wide so about 200mm of the workpiece ends up underneath the rail, that's essentially why there are two methods needed. It took me a while to get my head around that.
  • A pair of rail clips would be really good when using this technique as its a bit fiddly to get everything lined up and squared up against dogs and the stop block
Tips
  • Make your first mark on your MFT top as early as possible and get the first mark out of the way. You can use spoiler boards under your workpiece and save having to damage your MFT top BUT the convenience of NOT having to protect the table top with every cut is quite significant so I have decided not to protect the top as I don't want to lose efficiency. You can replace the top for £40 anyway.
  • On my makita equipment, the rail is 4mm thick, therefore I set my depth on the track saw to the material thickness + 4mm. So if I'm cutting 18mm ply I set my saw to 18+4+1 = 23mm. This will make a 1mm deep mark in the MFT top.
  • I would say that if you DONT want to buy a rail square and you have a need for regular cutting of full sheets (8' x 4') then an MFT is not going to solve all of your track saw issues.
  • My 1.5m long rails are a bit of a pain sometimes and I would like a shorter one to give me the option.
  • Clamps - make sure your clamps will fit through the holes. Mine dont and fortunately I designed in an overhang around the MFT which means I can at least clamp at the edges until I get a clamp that CAN fit through the holes
my rail clamp NOT fitting through the hole in the MFT top:
IMG_20230312_111027.jpg


My opinion
As I mentioned earlier, take this with a pinch of salt as I am pretty much a total amateur but here are my thoughts having spent a few days with an MFT:
  • A rail square is essential for sheet goods and pretty much a dream to use if you like speed, quality, repeatability and efficiency (as I do)
  • A rail square is semi essential if you plan to regularly cut anything wider than 500, because a standard 700mm MFT top won't do it unless you turn it lengthways AND have an extra table for supporting the workpiece. This is something I didn't even consider so really think about this one before you dive in and start buying things to support your needs.
  • If I was going down the 'NON-rail square' route, I would 100% invest in a fence+stop for the MFT top - both Benchdogs and UJK both make something similar that can be quickly inserted into the table or taken out when you need the full table for larger workpieces
  • I have noticed that the UJK one does have a stop but doesn't have a tape so that feels like a miss in my opinion
  • For me (in my little experience) the fence and stop system is where a lot of the efficiency is - it gets rid of marking up, which does remove some human error but it's the speed and efficiency of it that I love the most.
  • My rail square (plus little fence+stop) is the thing I use 90% of the time, as oppossed to using the dogs to align the rail and workpiece at 90 degrees
  • IF I had a fence+stop for the MFT top also (which I don't) then I might use the square only 50% and the MFT the other 50% for everything under 500mm wide.
  • MFT is useful for assembly operations, not just for cutting. For example when I made my drawers I simply lined all the sides up against my dogs, then clamped them down before screwing in the pocket holes.
  • I wish I had bought some rail clips at £15 - it's totally useable as is but it would be much better with the clips
  • Not having a hinge restricts my max width of workpiece to 550mm if using he MFT without the rail square
  • If I installed a hinge I suppose I could increase my max cut width to about 700mm - that would really change things as lot of things are 600mm wide (probably not a coincidence)
  • Note, my workshop has 2.1m headroom and a 950mm bench height - so using a hinged rail could be problematic with a 1.5m rail as it would hit the ceiling! Something to consider if you are planning an MFT setup yourself and have a UK shed or garden room with similar height issues!
Overall, I am 100% convinced that the MFT + rail square route was a good road for me to go down - I really enjoy using the system, and it allowed me to build things faster than I would have done otherwise. Its potentially more accurate also which really helps with cabinets and drawers.

For me its hasn't been merely a novelty, it has immediately become a part of my standard workflow and I am using it every time I use the workshop now. Ultimately, this has removed the need for me to have a table saw, so in that respect it's a win, but its also made my track saw (which I already liked) significantly faster at getting the job done.

In a nutshell, here is the workflow:
1. set the length (in this example to 600mm)
IMG_20230205_123148.jpg


2. Line up the rail and run the saw down it and voila; 600mm:
IMG_20230205_123141.jpg


Future upgrades
  • CLIPS: A couple of rail clips at £15 are a no brainer. Yes you can make them but you need some hardware to attach to the rail so I may as well just buy the clips.
  • FENCE: Definitely a fence + stop for the MFT top is something I would like to have
  • GUIDES: I would like some parallel guides for helping with thin cuts (<200mm) - I need to give that some more thought, not entirely sure if that would solve anything or just be something else to faff with. At the moment, the stop block situation is working OK ish.
  • HINGE: this is the big upgrade but typically quite expensive - it would take my cross cut capacity to 700 from 550, which is a more significant impact than the 150mm shortfall would suggest (as a lot of cuts are 600mm).
Finally
I will iterate once more than I am not writing the above as an expert on this topic, I am only sharing the information from a beginner perspective - it is information which I wish I had at the start - I think this will help somebody in a similar position but it certainly wont be useful for seasoned users.

I am sure Peter Millard would die laughing if he read this post, but I honestly learned a lot of this stuff on the fly after I started to use it without fully realising it beforehand - I hope its useful for somebody! And finally, if you are thinking about getting an MFT / track saw, Peter's youtube channel is an information goldmine if you don't know that already :)

Martin
 
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Sounds pretty similar to my own mft experience, including those very same clamps! You can cut away some of the metal at the bend to make them work, it probably weakens the clamp but it's not been an issue for me. I ended up buying 4 of These when Axminster had them on offer a little while back and they're a big improvement, and much cheaper than the fancy ratcheting clamps Festool make.

Regarding the hinge, I highly recommend looking at Peter Millard's Plans for a wooden hinge, I made mine from some cheap ply a few months back and it's working really nicely, and as you say gives you that extra cross cut capacity.

I own a bench dogs rail hinge and parallel guides, never got around to buying the repeat guide thingy, certainly looks useful though. Parallel guides are really useful for repeat rips, I don't think I'd trust the square at the end of a 3m guide rail for ripping sheets down for wardrobe sides, but for shorter cuts your setup is probably absolutely fine.
 
A standard 718mm deep MFT cannot be used to cut anything wider than about 550mm as you need a long dog at top and bottom of workpiece (to support the rail) which reduces the usable width of the table by about 150mm
Is this because you are using a cordless saw, are the batteries the part that collide with the tall dogs ? On my corded Makita I do not have issues with the tall dogs on material at least 12mm thick.

Clamps - make sure your clamps will fit through the holes.

Not an issue if your MFT top has the matchfit dovetail slots inbetween the rows of 20mm holes.

You have not mentioned parallel guides, I think for long cuts these will deliver better results than the rail square, so parallel guides to cut to length and the rail square to cut these at 90° for the actual parts.

With a rail square and parallel guides I think the hinge system becomes just a luxury, unless your bench can take a full sheet then with ail square and parallel guides you can easily work on tressles anywhere.
 
Ive just ordered an mft template jig thing and started a torsion box for site use. It made sense in my head to do it as a full 8x4 but i ended up using a sheet of 12mm for the top, nearly a whole sheet for the torsion box slats and then realised its gonna be heavy 🤣 I'll probably skip the bottom sheet / skin.....
 
With a rail square and parallel guides I think the hinge system becomes just a luxury, unless your bench can take a full sheet then with ail square and parallel guides you can easily work on tressles anywhere.

I would disagree. With a fence, the accuracy comes down to how square the rail is against the fence. This is usually a one-time procedure, and repeatable ofter this.

With a parallel guide, you have to adjust two setting (arms) each time, and they must be identical. And the next time you need this, you do it all again.

15.jpg


It is not essential to have a rail hinge. The rail can be held against dogs as well. What us then important is that the dogs holes are accurately made. In other words, square. Dogs may be used as a fence for a board and as a stop for the rail. This method also is a one-time set up.

Regards from Perth

Derek
 
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Ive just ordered an mft template jig thing and started a torsion box for site use. It made sense in my head to do it as a full 8x4 but i ended up using a sheet of 12mm for the top, nearly a whole sheet for the torsion box slats and then realised its gonna be heavy 🤣 I'll probably skip the bottom sheet / skin.....
8 x 4! Wow 😅
That would be a great luxury for site use but I really wouldn't want to carry that around, the size and weight would be pretty incredible I imagine.

I think if I wanted something for site work I might look at the Bora centipede, you can attach multiple tops together with that I think and it looks really compact and handy

Got any pictures of your mammoth MFT?...

Martin
 
I think you might be missing a piece in your rail square set. There is a little square aluminium block with a grub screw that acts as a calibration guide on the ruler part. after you‘ve calibrated it once, you attach this to the ruler against the square and it acts as a repeat block for easy setup each time. You should only need your 200mm block once. The square block is in the photo on their website. Various YouTube videos show it but the actual instructions are rubbish from memory!
 
8 x 4! Wow 😅
That would be a great luxury for site use but I really wouldn't want to carry that around, the size and weight would be pretty incredible I imagine.

I think if I wanted something for site work I might look at the Bora centipede, you can attach multiple tops together with that I think and it looks really compact and handy

Got any pictures of your mammoth MFT?...

Martin
I havent recieved the mft jig yet, so the framework is fixed to the top, just sat on it. I left 50mm all around for clamping. The frame pieces are 80mm, which should be pretty stable. I'll almost certainly fit a border of mdf to the underside to stop the frame getting bashed apart as it's only glued ( pu ) and pinned together.
I figured that once its all in one piece it'll be fairly rigid
 

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Thanks for a great write up - I have been thinking about the rail stop. as for quick jobs I tend not to put my fence on the MFT - as I use it outside on a bora centipede. I have been thinking about a second one as they are really handy. I like the idea of the hinge with the mft fence but will wait a while
 
I still don't see the point. A huge amount of effort and expense to solve a non existent problem. Yes and it is just a box, torsion doesn't come into it!
 
It is not essential to have a rail hinge. The rail can be held against dogs as well.
Yes I do use these clips and benchdogs

https://www.axminstertools.com/ujk-technology-dog-rail-clip-pair-102973
If you use these parallel guides they are very precise once setup

https://benchdogs.co.uk/products/330mm-parallel-guide-system-festool-makita
or these

https://fctools.co.uk/product/parallel-guide/
And @Jacob does have a point, everything that we can do using the more expensive options of rail squares, hinged guides etc etc can be done with far cheaper options but maybe with a little more effort and more skill. I think the biggest benefit is that with a tracksaw and these accessories that anyone can cut a sheet into the required pieces but how many could do it with a handsaw !
 
................. I think the biggest benefit is that with a tracksaw and these accessories that anyone can cut a sheet into the required pieces but how many could do it with a handsaw !
You wouldn't do it with a hand saw. Rough cut maybe and then a plane.
But with a tracksaw you don't really need an MFT in the first place.
With a hand circular saw you don't even need a track - a length of MFC shelf and a couple of clamps will do, or just the fence alone.
 
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I think back to the years I just used a circular saw and length of angle iron, with clamps which is not much different to using a length of MFC shelf except a bit heavier. I suppose if it brings more people into woodworking then it has to be a good thing and if these extras make it possible then it is good business for the likes of Benchdogs and Fc tools which are both UK based.
 
I think perhaps I haven't been very clear about the 550mm crosscut restriction.

I took two pictures this morning to help explain:
IMG_20230327_072618.jpg

IMG_20230327_072623.jpg


The table is 718mm deep and that board (workpiece) is 600mm wide/deep and 1200mm long. It DOES fit on the table BUT there is only space for one long dog, the other long dog doesn't have a hole available. This means you have no way to square up the fence against the workpiece because you need two long dogs for that.

So you either cut a smaller board, up 550mm max (probably not an option!), or you use a rail square, or you do it the non-MFT WAY and just mark up the workpiece and manually line up the rail with your lines then make your cut.

There is nothing broken about doing it that way, it worked that way just fine before MFTs came along, but it's faster using a rail square or an MFT to do it.

In my opinion the time savings are significant enough to justify the move to a new method, especially if making cuts is your day job and time is money.

Martin
 
I think you might be missing a piece in your rail square set. There is a little square aluminium block with a grub screw that acts as a calibration guide on the ruler part. after you‘ve calibrated it once, you attach this to the ruler against the square and it acts as a repeat block for easy setup each time. You should only need your 200mm block once. The square block is in the photo on their website. Various YouTube videos show it but the actual instructions are rubbish from memory!
Really? That makes a lot of sense!
Thanks for the heads up I will investigate this further 👍
Martin
 
Is this because you are using a cordless saw, are the batteries the part that collide with the tall dogs ? On my corded Makita I do not have issues with the tall dogs on material at least 12mm thick.



Not an issue if your MFT top has the matchfit dovetail slots inbetween the rows of 20mm holes.

You have not mentioned parallel guides, I think for long cuts these will deliver better results than the rail square, so parallel guides to cut to length and the rail square to cut these at 90° for the actual parts.

With a rail square and parallel guides I think the hinge system becomes just a luxury, unless your bench can take a full sheet then with ail square and parallel guides you can easily work on tressles anywhere.
No it's not a clearance issue, hopefully the pictures I've just added explain it better 🙂
I did mention the parallel guides in my future upgrades section 😃 but you might be right about them being better for long lengths than the rail square. There is some risk using them for repeat thin cuts though because any error on the setup of the guides will accumulate and your last cuts on the board might not be at 90 degrees. If that makes sense.... 😃
 

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