Grooves in a big MDF-board

[pewa]

Hi everyone!<?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>
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I’m new here on this forum, but I’ve been a frequent guest for some weeks and I’m quite impressed with all the knowledge that seems to be around! I live in <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-comffice:smarttags" /><st1:country-region><st1lace>Sweden</st1lace></st1:country-region> and here up north there is no such forum around, so I’m thankful for the internet!<o></o>
I’m also quite new to woodworking as a hobby and consider myself to be a happy amateur. <o></o>
Now my question; I’m about to route some grooves into a 2200X1200 mm. size MDF-board. The plan is to make it look something similar to an old panel, it will serve as the back to a build-in shelf for my living room.<o></o>
I’ve tried to make the routing with the help of a long aluminum ruler, but the result sucks! The board is to big for me to be able to reach all over it and make the grooves straight.<o></o>
Does anyone know of an easy solution or do I have to by one of those quite expensive Feestol guide rails that I’ve seen somewhere? <o></o>
It would be nice to hear your opinion!<o></o>

[Greg Q]

Hi Pewa, and welcome. Do you have any other straight edge available? Even a 200mm wide strip of 18mm MDF would be rigid enough to use as a router guide. (Perhaps an offcut from somewhere?)

I like the Festool guide system, but it's a little pricy for one job. Trend (uk) has a guide that is suitable, but I am unsure of the maximum length available.

Good luck

Greg

[mickp]

why not make a rebate jig to suit the base plate of your router, clamp the jig to your mdf at each end and with a couple of toggle clamps in the middle and away you go. easy to stop & start the router without any problems while you move so that you can reach, quick & easy to re-position for the next cut

[redwood]

How bout a sub base that screws onto your router base with a auxiliary fence screwed on the same distance as the distance between your grooved panneling on the mdf. If the grooves are 8mm x 5 mm deep then make your fence the same (little bit less so it slides nice and tight) and make it 400mm long. rout your first groove using it as a guide then put that into the routed groove and use that as a guide for the next groove, then the other and other till you have a series of exact grooves done fast and quick migth work might not:confused: give it a try

[ozwinner]

Hi and welcome.

What sort of bit are you using?
I would use a spiral upcut bit, the bit will make all the difference too.

Al