Parallel Guides brass screws do I tighten them each time?

[Acrobat]

Hi
I've just purchased the Parallel guides and am in the process of calibrating them....
Do I tighten the brass screws either side of each "T"? then loosen them to get the guides off the rails? Whats the point of these screws when the large round green knob and flip lever on the back locks the T guide in place anyway? Is it to get the guides square? I notice there is quite a bit of play there on the rails before I lock the green knob and flip down lever.. How tight do you have the brass screws in everyday use?

I do find it tricky to get the calibration set equally for both T' guides, seems each time I loosen the screws and tap the ruler in or out they go too far or not enough and I'm re-checking over and over. 1/2mm difference each time.
Is there an easy method I'm just not getting?
I've watched the Youtube clip on Parallel Guide setups with the Festool guy demonstrating them but he doesn't show how for these parts but does show the adjustments for the extensions, which I haven't tried yet, but they look simple enough.
thanks

 

[Sparktrician]

Make sure that they're adjusted right once and leave them alone.  Use the big green wheel and the lever to snug the rail to the parallel guides. 

 

[Acrobat]

So what do i do with the brass screws, tighten them to the rail each time I put them on?

 

[sancho57]

I adjust them just enough to where the guide slides on the rail with minmum side to side movement. If that makes sense.

Ya dont need to clamp down o them

 

[Acrobat]

Ok ta, I did try at first to tighten them as I assumed you needed to and left 2 indentations on the guide rail so wasn't happy about that.
I'll tweak them so there's a tight-ish fit with less slack but enough to slide them on and off easily now.
Man there is a knack to getting the guides slide on and off, I've found spraying them with crc/wd40 sure helps there!
thanks

 

[roblg3]

Back those screws off.  They are only there to permanently affix the guides to the rail.  That is their only purpose.  There's no need to worry about squaring the parallel guide with the rail.  It doesn't matter if they are square or not.  I found it pretty easy to use a steel rule slid under the rail to the index on the guide and measure to the edge of the splinter guard of the rail.  1/2 a mm is still way better than you'll ever get on a table saw!!

 

[Acrobat]

Thanks Rob, and everyone else who replied here regarding those screws and helpful advice.
As always, much appreciated.
As an aside, it would have been easier originally if the instruction sheet had better detail and could actually be used as an instruction sheet! It shows little lock images for the brass screws so I assumed wrong thinking I needed to screw them down tight each time. 

I look forward to giving them a try in the next weekend and testing them out.

 

[fshanno]

If you tighten the brass screws it will remove wiggle and it will squeeze everything up.  It does improves repeatability on my set by a small amount.  I don't think it's as much as 1/2 millimeter but it could be.  I'd sure like to know what the official line from Festool is on those little screws.  The manual is vague.

As far as dead on accuracy goes there's one sure way to achieve it.  Here's what you do.  Adjust until you sick of adjusting.  You'll be close.  Now leave it alone.  Make your first rip a bit wide and check the results.  If it's not dead on then note the difference and compensate when setting the stop.  For instance, if you are half a millimeter wide on one side then cut half a millimeter when setting the stop on that side.  I've been known write on the arm how much to cut or add.

 

[roblg3]

If you go to festool USA, you can find supplemental manuals for tools!  They are significantly better.  I've been to several festool training classes and been told about those screws by Brian sedgely a festool employee and festool trainer as well as Greg paolini a festool trainer that the screws are only for permanently fixing to the rail.  Hope that helps

 

[paulhtremblay]

I do find it tricky to get the calibration set equally for both T' guides, seems each time I loosen the screws and tap the ruler in or out they go too far or not enough and I'm re-checking over and over. 1/2mm difference each time.
Is there an easy method I'm just not getting?

A tip I picked up from here works as follows. Slide both of the end pieces to the middle so they touch. Adjust one of the measuring pieces to your desired width. Use your fingers to adjust the other one to exactly the same spot. (Your fingers are a much better guide than your eyes.) When your finger feels no difference, slide the parts back to the end.

I use this method each time. It is a little difficult to slide the end pieces down my 2800 mm rail, but it works.

 

[Acrobat]

What a clever and simple idea, love it.