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

 

[ukworkshipper]

Thanks everyone! Really a collection of great advice, I am overwhelmed! I think people have different approaches, my neighbor has a festool track saw and he uses that for solid wood counters but I also see the jigsaw+router as a good approach.

I know the hob has a flange and I don't need a perfect cut, but my hob has ventilation holes (it's a 9kw induction) on the side and I wanted to shift it a bit to the right. So I have used my circular saw to cut off a few mm and straighten the cut, then used the jigsaw to make small adjustments, I had to work with what I had! I didn't plunge directly with the circular saw, I did sort of jigs at the beginning as suggested by @meccarroll and cutting across the grain I didn't notice any backforce, my circular saw is a small one (160mm). Thanks a lot for the warnings on using the circular saw.

When I was doing the final touches with the jig saw I definitely noticed how the blade was bending. I think also my problem was that the feed was not straight, so I already started at a wrong angle making it worse. In any case it seems that my cut without pendulum was a lot closer to 90 then when I used the pendulum, but maybe it was the feed. I managed to go from a 82-85 angle to a 88-89, so I am happy with the final result but not having the right tools is a lot more effort and time wasted. I can't afford to buy every tool, and now I have to decide between a router and a miter saw (making a hardwood floor). The router I could use it for the kitchen sink cutout and to make round corners for the other counter top. So I don't really know which one to get considering I don't plan to install another counter but the miter saw might have more uses. Any advice?

 

[Bingy man]

Do you mean a hardwood door ? A track saw can easily cut sheet goods etc but a router can do so much more so that would be my choice

 

[ukworkshipper]

Do you mean a hardwood door ? A track saw can easily cut sheet goods etc but a router can do so much more so that would be my choice

Hardwood floor, not door

 

[TRITON]

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.

We'd a Festool rep turn up at college touting his wares. He had a jigsaw on show and was showing off its ability to cut perpendicular due to placement of bushings down near the base(A good idea fair enough)
Me though as 'agent provocateur' handed him a bit of ash and asked him to make a straight ripping cut.
He was reluctant, but in front of 20 students and the lecturer(who had a bit of an evil smile) complied.

Wobble city

 

[macetownhouse]

Hello, I am cutting 50mm Douglas Fir with a lot of resin and hard notes for large windows, had a cheap jigsaw where the blade went anywhere but straight. Invested in Milwaukee Top handle the non Fuel one. Kept about 10mm from template and top guided bit to finish.
My point for £100 the Erbauer 1/2 router and £ 40 bit might be an option.
Cheaper than a new Kitchen top and a router as well.

 

[Jameshow]

Could you router square and trim it with some offcuts of oak from the cut out??

 

[ukworkshipper]

How are the Parkside routers such as the POF F4?

 

[okeydokey]

After you had jigsawed and it came out at the wrong angle would you have been able to straighten the cut with a handsaw?

 

[TheUnicorn]

Could you router square and trim it with some offcuts of oak from the cut out??

why trim it? it is covered by the sink?

 

[Woodworker Ireland]

Hey folks,

I hope someone can spare some advice, I am really disappointed by these cuts I have made on a kitchen counter top. I have been doing woodwork for a few months and can usually get pretty straight and precise cuts with my jig and circular saws. This is the first time I have made this type of cut inside a countertop. It's a solid wood oak counter top, 40mm thick, and this was a rectangular cutout for a stove.

I drilled a whole in each of the four corners and then used a Bosch 130 jigsaw with a T308B blade, initially I didn't use the pendulum but I noticed it was taking very long so I set the pendulum to 2. I had the impression that the jigsaw was pushing me towards the inside. Once I was done I realized that almost none of my cuts were at 90°.

Pictures of shame
View attachment 191102View attachment 191103

What did I do wrong? Is it something wrong with my jigsaw?

Is there a way I can partially correct this? Should I do a pass with my circular saw to straighten this mess or again with the jigsaw?

Any advice is greatly appreciated, especially as I will have to make a cut for the kitchen sink and then cut the corners of another counter top.

I always use a circular saw on hob /sink cutouts. Turn worktop upside down straight cuts with circular saw and corners with jig saw. Id say ive done hundreds this way.

 

[ukworkshipper]

After you had jigsawed and it came out at the wrong angle would you have been able to straighten the cut with a handsaw?

I don't have any decent handsaw, but I think it could be an idea.

 

[ukworkshipper]

I always use a circular saw on hob /sink cutouts. Turn worktop upside down straight cuts with circular saw and corners with jig saw. Id say ive done hundreds this way.

I think that's what I will do for the sink. Usually I don't bother to turn upside down, I just put duct tape around the cut and I don't any splinters.

 

[ukworkshipper]

According to Bosch the blades you used are suitable for softwoods up to 50mm thick, your tops are hardwood so perhaps you've used the wrong blade. In my experience a courser tooth, up-cut blade is better for cut outs in hardwood, never use pendulum action as this can cause chipping, cut slowly and let the saw cut through at its own speed without forcing it. Never use a down cut blade (as suggested) in solid wood, they will not cut satisfactorily if at all and will be very difficult to use, if not impossible.

Thanks for the suggestions. The Bosch documentation, that I have also received from this forum, states "EXPERT Hardwood 2-side clean T308BF". What blade would you suggest? I don't see any blade that's exclusively for hardwood, all of them have a bunch of type of wood listed. Maybe the Bosch T101BF or the T308BFP? All these codes drive me crazy!

So progressor blades are not good for this type of cut?

 

[Chubber]

maybe I should try the circular saw instead and finish the corners with the jigsaw.

No, no no, no... Did I say no?

An accurate 40mm (plus a bit) plunge cut with an ordinary circular saw in a costly piece of material is something I would only attempt in extremis. With respect to Perry the O.P. would not ( by his own admission) seem to have a toolbox full of experience, so even starting/ stopping a track saw precisely enough is a 'big ask' (I think that's the current vernacular)

With reference to the foregoing -

1. A downcut blade is only needed for cheaper laminations.
2. Pendulum is your pal.
3. Don't use a very fine JS blade, you want the big sawdust to carry away the heat, give yourself an easy/accurate start by making the 4 corner start/end holes at least 10mm.
4. Hold down two strips of 1/4" batten with double sided tape to make a railway track in which your JS can sit whilst it burbles away in a straight line with very little forward push from you.
5. Oil the little guide wheel and shaft, check base plate is square to blade.
6. Make a note to buy Chubber a pint.

There, now I feel like a tetchy schoolmaster. Wonder where I'll get one this time of night?

 

[Jameshow]

why trim it? it is covered by the sink?

Thought it was for a inset cooker...
Sorry my mistake?