Scorch marks when routing with template

[AstroKeith]

I've been routing out some cutouts in 18mm birch ply using the MFS template jig. The jig is great overall and I've found cutting circles and arcs very good.

My problem is scorching of the timber at the corners when routing square cut outs. I've tried a number of techniques but none have been 100% effective. What do others do?

I've tried new bits, taking very small cut/plunges, rapid 'cornering'. Havent tried changing speed though. Using 15mm bits in an OF1400.

Grateful for any advice/comments!!

 

[Roseland]

I think (but don't know for sure) that it's caused by going too slowly.  I say I don't know because although that is the prevailing theory I've been unable to go fast enough to stop it happening.  But the fact that it happens mostly on the corners supports the speed theory.

I've not tried slowing the router, but I guess that might help.

Good luck and stay well,

Andrew

 

[CeeJay]

I’d definitely suggest lowering the RPM on the router. The glue in plywood can quite easily burn at higher RPM.

Also have a look at your bit. If it’s gummed up with pitch or resin that can also cause scorching. A quick clean with blade and bit cleaner can make a big difference.

Sent from my iPhone using Tapatalk

 

[waho6o9]

Maybe plunge cut the four corners first and then proceed with routing the square.

 

[AstroKeith]

Maybe plunge cut the four corners first and then proceed with routing the square.

Brilliant - worked a treat - thanks!

 

[waho6o9]

Maybe plunge cut the four corners first and then proceed with routing the square.

Brilliant - worked a treat - thanks!

You're welcome, glad I could help.