Hi, Welcome to the forum! 

Melamine is one of the few things that a rail might not get a good grip on. A couple Festool rail clamps will solve that issue.

It sounds like you have it well supported throughout the surface, but if not a flex in the material can cause loss of grip.

Also try to make sure you are always pushing the saw from straight in line with no side force. Which can be hard to do on  a wide cut when you need to lean over the sheet.

Seth

I have a set of clamps but my setup it won't work unless I straddle the melamine over the edge of the work table and then assuming I can clamp one side, the other side will not overhang.  My work table and sacrificial ridged foam is 4 x 8

Suction cups?  I have never seen or heard of them?  Can someone point me to them?

Also has anyone ever replaced the rubber strips on the back of a track?  Does it help?

thanks

this might work

https://www.amazon.com/Festool-489790-FS-Rapid-Clamp-System/dp/B00149B7W6/ref=sr_1_10?keywords=festool+clamps&qid=1573691358&sr=8-10

What Birdhunter said. Tape your track down and then cut through the tape. Easy.

@tjbnwi Tom you seem to be an expert on this.  Do you know what is the difference between 492617 or 493507.

@vkumar,

What @mwolczko said. You need the adapters to use the Geckos with the guide rails.

Tom

Another thing I've found useful is to first anchor the rail with clamps or geckos, then make the first (scoring) cut 2mm deep.  Without moving the rail, make the second cut full depth.  This seems to help on really thin melamine that wants to chip out quickly. 

Someone should figure out how to make a Festool track stick to a surface with vacuum like Mafell has done.

It exists! I've been keeping quiet the last year.

I had this problem when making some cabinets. So, I decided to try out an idea that uses vacuum pump clamping (not a dust extractor). After a few iterations and much use over the last year I finally have a finished CNC’d product that I'm really happy with and just geared up to produce small scale so hope there is a demand.

Benefits of my design are that it requires no access to the underside of the work, so is great if your on an MFT or on the floor.  No tool required to attach to the rail.  No movement of the rail when clamping force is applied.  Also, because it uses a vacuum pump system (VacSys or other) you can align the rail and clamp the rail before you start cut leaving both hands free to guide the saw with no awkward manoeuvrers trying to hold the rail down which is much safer.

I have a few units made and I'm hoping to sell them, probably via e-bay to begin with in the next couple of weeks.