What's wrong with my circular saw

[aveatry]

I am cutting kitchen worktop and used a circular saw and noticed the end of the cut is not square where the start of the cut is. Its a works saw with a De Walt blade. Is it technique or is something else going on.
See left side bottom is not square. You are looking at the front edge of the worktop I started the cut from the back to the front. The right side edge in the picture is the factory cut. Its not that rough its just pixelated - the cut is very good.

For my next cuts I plan to cut slightly oversize and square off with my router. Or put it on my table saw as some pieces are only 1m and 500mm

 

[big-all]

brand new blade 40-48 tooth cut upside down front to back and if it still wanders end off cut its possible overstretching is forcing the saw somehow but i have never had this happen with a circular saw
if its progressive along the cut it could be blade and fence not parallel ??
would expect burning on one surface iff its cutting off line as the back off the blade would be cutting as well so cutting hard work rather than smooth

 

[big-all]

several more edits to post above

 

[aveatry]

Its a 24tooth not new but good enough not to give chips to the serface . Fence I am sure was parallel I did do it upside down. I had it on the ground chocked up to clear the blade teeth only just sticking out, and then straddled the worktop so my body was in the middle and could reach both ends comfortably. Havnt cut anything this thick before so never noticed.
I have more to cut today so will pay particular attention to my technique and then check the results.

 

[big-all]

the worktop must be fully supported so when the final cut through nothing moves

 

[aveatry]

the worktop must be fully supported so when the final cut through nothing moves

I have worked out that is part of my problem. I have been cutting on sponge to protect the worktop from scratches, but I have done a few more cuts today on the sponge but paid very close attention to my stance and positioning and concentration at the end of the cut and now it is square, I think I was trying to "follow through the cut but must of lifted and twisted at the end.
I have more cuts to do but will be lifting the worktop off the floor on wood and not sponge.

 

[big-all]

thanks for getting back and being honest with your answer warts and all it how we all learn the most from each other

 

[aveatry]

I am fairly experienced with the saw and other types of power saws but maybe that was part of the issue and I was perhaps being too cocky at the end lifting it up and out of the cut. Having said that I have only ever cut 15-18mm stuff with it before which would not of mattered/ noticed so much.
If you look at the wonky cut you can see that is exactly what I have done - that is the end of the cut and I have lifted the saw and its tilted away from the body or the work piece.
Need to concentrate on keeping it against the fence and flat on the work piece.

 

[big-all]

that is the reason i gave my dewalt dw62circular saw away over 10 probably nearing 20 years ago when i got my 18v plunge saw as the track means 100% to the end with splinter protection

 

[aveatry]

that is the reason i gave my dewalt dw62circular saw away over 10 probably nearing 20 years ago when i got my 18v plunge saw as the track means 100% to the end with splinter protection

How does the track protect from splinter, never studied one up close. As I never use the saw freehand and always up against a fence then I see no need for my saw as it is and might swap for a plunge saw with a track so all I have to do is concentrate on keeping it down and not also square against he fence at the same time as is currently needed.

 

[Deleted member 174758]

Its a 24tooth not new but good enough not to give chips to the surface

24 teeth? On what diameter blade? 165mm? If so you normally need more like 40 to 50 teeth (at that diameter) to guarantee cutting a laminate worktop cleanly and in a perpendicular plane. You ideally also need a ATB (alternate top bevel grind) blade. Also what kerf is your blade? Very thin blades have a tendency to bend in the cut on thick materials - as indeed do blunt or dirty (resin caked) blades. I'm not saying you absolutely need the right blade, tooth profile etc - just that the further you stray from the ideal the more likely you are to get a bum cut

BTW skip the sponge. Any cut needs to be supported on a solid surface, e.g. a couple of 3 x 2s supported on trestles

How does the track protect from splinter, never studied one up close.

The track has a rubber anti splinter strip at the edge.

The other thing to note about plunge/track saws is that they mostly have twin lockable pivot points, one each to the front and rear of the blade. A conventional rip saw with a single pivot point at the front can easily have the saw "bent over" (i.e. the base of the saw flexes) by the changing of the direction of pressure applied to the handle at different points in the cut (i.e. as you are reaching further over the material). This occurs more with saws which have a sheet metal base than it does with an alloy base, but it can happen with many saws. On reflection that is probably your biggest problem

 

[big-all]

How does the track protect from splinter, never studied one up close. As I never use the saw freehand and always up against a fence then I see no need for my saw as it is and might swap for a plunge saw with a track so all I have to do is concentrate on keeping it down and not also square against he fence at the same time as is currently needed.

its brilliant first cut because the saw blade is up cut at the front it trims the rubber meaning unless the blade wanders all cuts are with a rubber edge supporting cut edge cleanly
2 or 3pencil marks on work track along the work track thrown on the marks with half pencil marks showing waste side
with a pencil mark along the exact measurement means half the mark thickness is on work side and half on waste side so you need the blade to cut on the waste side taking half the mark out
you should always have half the maks/line showing there when complete or somthing is wrong

 

[aveatry]

The other thing to note about plunge/track saws is that they mostly have twin lockable pivot points, one each to the front and rear of the blade. A conventional rip saw with a single pivot point at the front can easily have the saw "bent over" (i.e. the base of the saw flexes) by the changing of the direction of pressure applied to the handle at different points in the cut (i.e. as you are reaching further over the material). This occurs more with saws which have a sheet metal base than it does with an alloy base, but it can happen with many saws. On reflection that is probably your biggest problem

The saw in that respect is very good as it has an alloy base and the saw handle can rotate as you move

 

[aveatry]

The track has a rubber anti splinter strip at the edge.

I thought to stop splinter/ breakout you had to support both sides of the cut. So with one rubber edge do you have one good edge and the off cut a bad edge.

 

[aveatry]

24 teeth? On what diameter blade? 165mm? If so you normally need more like 40 to 50 teeth (at that diameter) to guarantee cutting a laminate worktop cleanly and in a perpendicular plane. You ideally also need a ATB (alternate top bevel grind) blade. Also what kerf is your blade? Very thin blades have a tendency to bend in the cut on thick materials - as indeed do blunt or dirty (resin caked) blades. I'm not saying you absolutely need the right blade, tooth profile etc - just that the further you stray from the ideal the more likely you are to get a bum cut

Its a dewalt 24 teeth 71/4 blade. Yes also a thin kerf. I should of done more research and got a better blade for the job. The factory edge is actually very good on the worktop so I have used that on critical areas ( I have 4 with 2 tops ) and the bad cut I made in the picture is in a place where its not seen/ noticed. The last couple of cuts will only be 500mm wide and those will be going on my table saw after a rough cut with my circular saw. Table saw I have a 40 and 60 tooth blade to choose from.