cutting conti

[eggplant]

Hi all,

I'm sure this must have been covered before but I had a search and cant find anything.
I always struggle cuttiong contiboard, I always manage to get small chips in the surface opposite the blade cutting direction (if that makes sense) I usually use a black and decker circular saw (700W i think) but recently got a table saw from B & Q as I had loads of cutting to do and was hoping this would help - it didnt! I tried goinf fast, slow, inbetween but I still get a clean cut on one side and a not so clean on the other! I'm sure there must be some trick to this, can anyone enlighten me?

Thanks

 

[skybluescooby]

Have you tried cutting it upside down, so that the unused side is facing you when cuting, helps eliminate the chips.

 

[Scrit]

I recently got a table saw from B & Q as I had loads of cutting to do and was hoping this would help - it didnt!

OK, the professionals use a panel saw with a small contra-rotating scoring saw unit just in front of the main saw blade. This scores the surface to a depth of 1mm or so and means that the descending blade cuts cleanly on the top surface and doesn't break out the melamine on the bottom surface. That's obviously not an option, but the following may be:-

If you are not using a carbide (TCT) blade you should be.

Make sure that you are using a blade designed to cut MFC (melamine faced chipboard). It will have an alternate top bevel or triple chip design and many teeth. It won't cut solid timber, so don't try. Even better are the special hook angle blades sold specifically for cutting sheet stock (though not normally available in sizes under 9in). Suitable blades are sold for portable saws and may be of use in a small table saw - make sure that the riving knife (behind the blade) is thinner than the kerf of the cut but thicker than the body of the blade.

Make sure that your saw has adequate dust extraction - hook up that vacuum!

If it is possible make-up a zero clearance insert around the blade from MDF or plywood. Standard blade inserts have very wide slots which allow chipping.

Adjust the blade so that the teeth rise above the board you are cutting by only a few millimetres.

Support the work as it comes off or goes onto the saw. If the sheet is bowing over the saw table you will get chipping.

Then play with the feed speeds.....

Scrit

PS Contiboard is Wheetabix with a coating. Try to get Egger, Sonae, Caberdecor, Kronospan, Finsa or Polyrey (from a sheet stock merchant like Arnold Laver or Hills Panel Products). Contiboard is markedly poorer in quality

 

[eggplant]

Many thanks for the detailed reply, I will try out your suggestions this weekend, I have never heard of the other materails you mention but will have a look for them.

Thanks again

 

[Scrit]

Eggplant

Years ago I learned how to get two decent edges on a piece of MFC usingjust a hand circular saw - all it needs is a sharp, fine toothed TCT blade, a strip of hardboard several inches wide, a couple of strips of chipboard (better still 3 or 4) and a plywood straight piece. The hardboard is sacrificial and everything else gets reused.

Place the two strips of chipboard parallel on the garage floor (or any other hard flat surface). Position the MFC on top of the chipboard strips. Mark the line you want to cut and use a square to mark the ends of the MFC. Lay the hardboard so that one edge just covers the cutting line. Lay the plywood straight edge on top of the pack parallel to the cutting line - it is best to make-up a couple of MDF/plywood spacers the same length as the distance from the blade to the left side of the circular saw plate. Clamp the plywood/hardboard/MFC together. Set the saw blade to just protrude beneath the pack by the depth of the teeth. Make the cut running the left side if the saw base plate against the plywood batten. Gives a good straight edge with minimal chip-out..... And it's what I used to do before getting a plunge saw/rail set.

Scrit

 

[eggplant]

Hi,

thanks for that, I'll try that before I go out bying new blades and stuff. Can I just confirm I get your idea right - basically clamp a spare bit of hardboard to where I'm going to be cutting, so I'm cutting through both? , and the ply is basically a saw guide (I usually clamp a bit of wood to guide the saw as well)

by the way, is it me or are there a lot of people on here from Lancs? I only noticed that because I'm from Lancs myself

 

[Scrit]

Can I just confirm I get your idea right - basically clamp a spare bit of hardboard to where I'm going to be cutting, so I'm cutting through both? , and the ply is basically a saw guide (I usually clamp a bit of wood to guide the saw as well)

Yes!

By the way, is it me or are there a lot of people on here from Lancs? I only noticed that because I'm from Lancs myself

Nah! Must be you!

Scrit