Countertop cutout fail and how to correct it?

[Amplidyne]

Jigsaws don't cut square. It doesn't matter which model, how used, or which blades, the cut wanders off square.
It's a fact.
The only answer is a router.

 

[Spectric]

Jigsaws don't cut square. It doesn't matter which model, how used, or which blades, the cut wanders off square.

That tends to be my experience in material over 12 to 18mm thick, they just don't like cutting perpendicular but then they were designed to cut curves. If I get a need where the jigsaw is the only option then I would just buy the mafell as that with it's expensive thicker blades looks to be the only jigsaw that can cut perpendicular.

 

[johnnyb]

Don't plunge cut these solid wood worktops honestly that saw will spit out when the wood tension grips the blade. Composite worktops are fine but solid wood isn't safe. More specifically I've had v dodgy moments when cutting along the grain. Not an issue on the cross grain. Plunge saw or not use a jig saw.
The mafell isn't a game changer and the thick blade is intended for curved cuts in general which it does very slowly. I've had one for years and it's not worth the
Mulah tbh.

 

[scooby]

40mm solid oak can be a handful for most jigsaws which are best not used for the final cut anyway. I've fitted hundreds of kitchens professionally and would never use a circular saw either. Jigsaw to remove the bulk of the waste then a router to finish is quick and easy. A router is so useful you should have one anyway (I have 4), look for a Lidl / Aldi version if you want cheap, they're half decent and have 3 year warranty.

If you have hand tools you could use a block plane or even a sharp chisel to straighten the cuts.

Excellent advice. My jigsaw approach is the same. Anything thicker than 3/4" the jigsaw is for bulk removal only and the neat cut is done with a router. Disinterior advice (post 17) is also good but I'm not really keen on making plunge cuts in thick material with a track saw.
Jigsaw is definitely my least used tool.

 

[jcassidy]

I used a circular saw for exactly this, finishing the cuts with a panel saw. I didn't have a plunge saw at the time, or I would have used that.
I wouldn't dream of using a jig saw.
Now that it's done, I would use a rasp from the bottom side to remove material, keeping away from the top edge to avoid blowout. Or a small plane. I don't know what tools you have to hand
Hope this helps
John C