Need help with Circle Cutter & carvex 420

[3PedalMINI]

Ive used the circle cutter once before in a thin piece of plexiglass and it went fine. Now not so much.

I need to cut a hole for a sink in a 1.5" cherry countertop I made, which will be undermount so i need my circle to be perfect. FORTUNATELY I practiced on a piece of 3/4" plywood before i did the real thing, so far I've ruined two brand new blades and 2 splintergards  [mad]

I can get 5 or 6 inches (perfectly) and then the blade bends outwards, smokes and melts the splinter guard also wondering (pulling) it out of "square" so my circle starts to become an oval. i cannot for the life of me figure out what is happening. My saw is setup fine, adjusted fine and both times I'm using a brand new 75mm blade. I know for my 1.5" countertop i will need a 105mm blade, but I'm pretty upset right now that this isn't working right.

Any help or incite would be appreciated, what is more frustrating is there is no directions or videos on how to properly set this up, i know it seems like it shouldn't be this hard but obviously I'm doing something wrong.

 

[Stone Message]

Assuming the obvious things are right - grub screw adjusted for the blade etc. then it could be that you have set up the circle cutter wrong. There are two ways to do it and only one works otherwise the blade is not cutting at a tangent to the circle which will heat the blade - make sure that the pin goes through the correct hole - I think that I cover it at about the 9 min 30 sec point in this video:



Peter

 

[VW mick]

Hi

Personally I wouldn't try and cut a finished circle with a jigsaw

I'd make  a jig with a router on a trammel then switch to guide bearing cutter for the final cut on the actual top

 

[curt boyer]

Brendon, I would use a router to make that cut. I made a circle cutter for my 1400 that works every time. You make several passes at increasing depth and viola perfect hole!
Cheers
Curt