GRS-16 PE to square rail to fence?

mikev12345

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I just recently purchased the TS 55 Req-F-Plus-FS and am in the process of setting up a DIY MFT.  I bought a 48x40 CNC mft top, I've ordered a GRS-16 PE, a benchdogs.co.uk  fence, and I'm part of the 6th batch of benchdogs.co.uk quad hinge.  I still need to buy some sheet goods to make the MFT benchtop and sysport cart for it to sit on.  This reason I bring all of this up is even though I saved for this the financial outlay has been hefty with still smaller things still to buy (ie 20mm router bit, ratchet clamps, etc).

I know generally speaking people would use something like the TSO PTR-18 for this duty but I'm just not in the position to spend that right now(probably in 3 or 4 months).  I wish I could get the woodpeckers MFT square but supply chain issues makes it impossible to find in Canada and shipping from the US makes it as expensive as the PTR-18.

So I'm trying to figure out why I can't square the benchdogs fence to the tracksaw rail using the GRS-16 PE? 
 
I bought a rail square and quickly sold it.  Its good if you are doing lots of crosscuts that need to be square but not where speed and portability when not cutting on an MFT is more important than precision.  Cutting roof, floor, wall sheathing its ideal.  Cutting up cabinets or when cutting on a MFT the MTR is a much better choice for quick square ups and isnt a one trick pony as it also provides a good way of cutting angles on wide stock.  I dont use it for that but its available.  I would either see if TSO can change the order or sell it and get the MTR.  You can buy the MTR as just a triangle and add the other stuff later to save some money. 

If you really want and should dial in the square then you tube 5 cut method.   

 
Hi, have your cnc shop make a double thick mft style square or sinlge layer much cheaper. they can even cut alignment dog holes. this also
 

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afish said:
I bought a rail square and quickly sold it.  Its good if you are doing lots of crosscuts that need to be square but not where speed and portability when not cutting on an MFT is more important than precision.  Cutting roof, floor, wall sheathing its ideal.  Cutting up cabinets or when cutting on a MFT the MTR is a much better choice for quick square ups and isnt a one trick pony as it also provides a good way of cutting angles on wide stock.  I dont use it for that but its available.  I would either see if TSO can change the order or sell it and get the MTR.  You can buy the MTR as just a triangle and add the other stuff later to save some money. 

If you really want and should dial in the square then you tube 5 cut method. 

Aye the MTR-18/PTR-18 looks like a great solution.  I think I decided on the GRS-16 PE for sheet breakdown and in instances where I'm not using the MFT bench.  Also I bought it from Lee Valley since I'm in Canada and I used a cyber Monday gift card I've been sitting and lee valley doesnt carry the PTR 18.
 
mikev12345 said:
So I'm trying to figure out why I can't square the benchdogs fence to the tracksaw rail using the GRS-16 PE?

Assuming your CNC cut hole pattern is accurate (definitely worth checking, by the way; do not assume the hole pattern is perfectly square to the outside profile of the worktop), and the Benchdogs fence sits in those dogholes along the back row, you could use dog rail clips and long dogs to support the guide rail and it should be dead accurate. Here's a video which shows the long dogs and dog rail clips in use - they're fairly cheap given what you've already spent to get this setup up and running.


This assumes you're just wanting to make accurate 90 degree crosscuts. If you're doing any variable angle stuff, the MTR-18 is definitely the way to go.
 
As for the GRS16, you can use it for squaring, but it does not have much reference surfaces.

While the GRS 16 it is very precise itself, about same as DIN Class 1, it connects to the rails over only 150 mm or so and this limits the overall accuracy as the "back" side of the rail is not - absolutely - parallel at all times. I found this the hard way and that is why I would advise the FS-WA ahead of the GRS 16 PE for absolute precision - as it can be calibrated in complete set with the rail even when the start of the rail is a bit off.

If you /just/ want something for squaring stuff, get a quality engineers square instead if you not already have one.

Example I would advise if you were over here is the Kinex stuff, but should help you for references - there is a PDF with the DIN standard for reference.
https://shop.kinexmeasuring.com/en/precision-flat-square-kinex-300x200-mm-din-875-0-p8452c22c34/

A Class 0 DIN square /not sure of the equivalent US standard/ provides for  for 0.01 mm accuracy over the shorter 200mm leg. That is way better than a GRS can give you and is aplenty when you are squaring two otherwise straight lines line when squaring a fence. It is also great to have when you need a know-good square for referencing.

That said, MTR18 is a great thing. But it is IMO way overkill for squaring fences with it...
 
ryanjg117 said:
mikev12345 said:
So I'm trying to figure out why I can't square the benchdogs fence to the tracksaw rail using the GRS-16 PE?

Assuming your CNC cut hole pattern is accurate (definitely worth checking, by the way; do not assume the hole pattern is perfectly square to the outside profile of the worktop), and the Benchdogs fence sits in those dogholes along the back row, you could use dog rail clips and long dogs to support the guide rail and it should be dead accurate. Here's a video which shows the long dogs and dog rail clips in use - they're fairly cheap given what you've already spent to get this setup up and running.


This assumes you're just wanting to make accurate 90 degree crosscuts. If you're doing any variable angle stuff, the MTR-18 is definitely the way to go.


Dogs will never compete with a proper fence and good rail hinge. If you just doing installs where close counts then they are great. Otherwise no way will they beat the fence and hinge. 
 
Also, if you’re doing a lot of cutting it’s really annoying to not be able to quickly get the rail completely out of the way to remove and load workpieces.
 
Michael Kellough said:
Also, if you’re doing a lot of cutting it’s really annoying to not be able to quickly get the rail completely out of the way to remove and load workpieces.

That is how I started doing it, except I put the dogs to the back side of the sheet. It seems odd to me to have so the board is able to move in the same direction as the cut?
I do this with a cross-cut station that is 49" wide, so a hinge is just not in the cards for me. I have gotten used to it to the point that I don't bother with the clips anymore, just push the rail to the dogs and go. The only time I use the clips is on beveled cuts, which I try to avoid on this station. It just tears up the backing on the table.
I have thought about getting or making a couple of the wedge-style clips that Dave Stanton created on his Youtube channel. They seem more secure than just winging it, but far more simple than the spring clips.
My holes were drilled with the Peter Parfit system, very accurate.
 
Crazyraceguy said:
...
I do this with a cross-cut station that is 49" wide, so a hinge is just not in the cards for me.
...
Curious, what led you to the "49" cross-cut station route ?

Is it practical aka preferred/used also for "narrow" cuts - like making pieces from 15" wide boards etc. or have other "station/tool" for those?
 
The whole table-top is 49" wide, I think the max cut is something like 36"?, but I have a second row of holes that is closer to the side of the table I cut from. Those give a cut capacity of just over 20". I use the station mostly for cross-cutting the access panels on the employee side of the reception desks/ nurse stations that I build. I make full length (97") strips of material out of the off-cuts from cutting other parts. The access panels are either 18" or 20" high, depending on the countertop height on the inside. I keep the full length strips, with a 3/8" x 3/8" rabbet on the lower edge, ready as pre-cut stock. Then I can just cross-cut them as needed when fleshing out the inside of the desk. The sizes and spacing of the panels is generally not specified on the drawings, only the dimensions of any cabinets or supports. "Unless specified" the panels/spacing don't matter to anyone. I have developed my own general guidelines over the years, more for peace of mind/consistency than anything. I have always felt that a little bit of OCD is what makes a person good at this trade.
I am kind of in the process of developing a new "parts cart" for moving/storing my parts as I move around in my own area, as well as when bringing parts back from the beam saw. We have a bunch of drywall/panel carts and even more of the Hafele cabinet parts carts, but neither of those is ideal.

Sorry, we got off topic here.
 
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