Problem with cutting plywood with a circular saw

[DanEng]

Hello to all,

Following the very good advice and help everyone offered here, I might have found the reason for the wide cut (I am understanding that it is called kerf) and also why the saw is always tending to one side. I have observed and checked with a combination square that the bottom plate and the line of cut are not parallel. I am attaching some photos. Touching the combination square ruler to the blade at the front of the saw leaves about 2mm gap at the back of the blade. I tried this with two blades to confirm that it is not a defective blade.

 

[cgrutt]

Yep that's part of the problem anyway. Is there any way to adjust the base plate on other side? You may need to add a shim or two if it isn't adjustable I'm not familiar with that saw.

 

[tarbellb]

Yup
that's a problem

Circ saws are pretty basic, you can likely just tweak(bend) the stamped metal shoe+hinge for better alignment

Be sure to measure from front and back of the blade to side of shoe that contacts the guide, not the top. Just in case it's not square.

 

[MongoTA]

You want to confirm the distance from the EDGE of the plate that rides against your straight edge guide to the front of the blade is the same distance as the EDGE of the plate to the back of the blade.



If it needs adjustment, there are a few screws that hold the saw body to the plate. Loosen them as needed, adjust the plate, tighten the screws then remeasure.

Good luck!

 

[DanEng]

Yep that's part of the problem anyway. Is there any way to adjust the base plate on other side? You may need to add a shim or two if it isn't adjustable I'm not familiar with that saw.

I do not see any adjustment for this kind of misalignment. I will check if I can insert a shim somewhere or try to bend the metal connections from the base to the main housing.

 

[cgrutt]

Sole usually pivots on front and locks on back with a cam or bolt. You can probably put a washer or two at one of these points where it attaches to saw to close up some of that gap. I'd try that before bending anything.

 

[DanEng]

What saw are you using? I have seen cheap saws that had the shoe not square to the arbor.

Parkside PHKSA 20-Li B3

https://www.amazon.de/dp/B0BZWYV4XT/

And yes in fact the guide is not square to the arbor as can be seen in my posted photos unfortunately.

 

[DanEng]

Sole usually pivots on front and locks on back with a cam or bolt. You can probably put a washer or two at one of these points where it attaches to saw to close up some of that gap. I'd try that before bending anything.

Yes it is the adjustment to set the depth of cut, right? I was thinking of inserting a washer between the cam and part attaching the base.

 

[Sumboodie]

Track saw works much better in my experience. Wrestling a big sheet on a table saw is all but impossible to do with precision if you're working alone.

Unless you have a huge table saw like Norm Abrams. Cutting a 4x8 or larger sheet on a contractor sized table saw is a 2 person job.

 

[dogdog]

Unless you have a huge table saw like Norm Abrams. Cutting a 4x8 or larger sheet on a contractor sized table saw is a 2 person job.

you can cut them down with one person, just slower... and more sore and pain...

 

[f121]

If this is a one off job, look at hiring a circular saw that's straight? Or maybe buy a new one?

 

[My Old Tools]

Is the blade on backwards?

 

[alfadan]

For some reason I doubt there's any way to adjust an amazon circular saw

 

[whateg01]

For some reason I doubt there's any way to adjust an amazon circular saw

 

[tarbellb]

For some reason I doubt there's any way to adjust an amazon circular saw

Does ANY circ saw have a adjustment for this?

 

[dogdog]

Does ANY circ saw have a adjustment for this?

The Hitachi corded one I have when you take out the frame it is held by three screws, pretty sure the other two craftsman pro and craftsman framing one is the same way. Although I never have to align them but did have to take it apart to regrease and dust off... so not exactly sure about OP's brand... doesn't seems like it's a brand marketed in the USA...

 

[tarbellb]

The Hitachi corded one I have when you take out the frame it is held by three screws, pretty sure the other two craftsman pro and craftsman framing one is the same way. Although I never have to align them but did have to take it apart to regrease and dust off... so not exactly sure about OP's brand... doesn't seems like it's a brand marketed in the USA...

Interested to see what those look like, is it adjustable or just hardware vs spot weld?

Got pics!

 

[dogdog]

Interested to see what those look like, is it adjustable or just hardware vs spot weld?

Got pics!

I can take it apart tomorrow it’s just machine screws at least mine is again not sure ops

 

[DanEng]

Hi all,

I inserting washers between the cam and part attaching the base, and aligned the blade as much as I could. Now the cut is much better. The kerf is a lot narrower than was before, around 3mm which is very near the 2.8mm stated on the blade. Also, the tendency of trying to pull to the side stopped. There are other things that I do not like in it, like for example, the laser and notch on the base are not exactly aligned with the blade path, and the zero degree mark of the base does not exactly reflect zero degrees. However, it is somehow usable now. Maybe I am expecting too much now.
I think I will eventually get a Makita.

 

[bb29510]

My suggestions come from four years of teaching Adult Education Carpentry classes, where I focused heavily on using a circular saw. I quit teaching this class for many factors, but a big one was the very poor condition of the saws the class had to use, and the large class sizes. Frankly, I was afraid someone was going to slice themselves with a saw!

saw that happen in shop class, the boy would cut and then place the saw on his knee while blade still moving, the boy was trusting the guard to close, it didnt

 

[DanEng]

The Hitachi corded one I have when you take out the frame it is held by three screws, pretty sure the other two craftsman pro and craftsman framing one is the same way. Although I never have to align them but did have to take it apart to regrease and dust off... so not exactly sure about OP's brand... doesn't seems like it's a brand marketed in the USA...

The circular saw I got is Parkside, it is a brand sold by Lidl supermarkets. For DIY, they are good value for money, at least till this episode. Regarding the attachment of the saw body to the base/frame, it does not seem to have any screws or adjustments.

 

[Old Man Roger]

Hello to all,

Following the very good advice and help everyone offered here, I might have found the reason for the wide cut (I am understanding that it is called kerf) and also why the saw is always tending to one side. I have observed and checked with a combination square that the bottom plate and the line of cut are not parallel. I am attaching some photos. Touching the combination square ruler to the blade at the front of the saw leaves about 2mm gap at the back of the blade. I tried this with two blades to confirm that it is not a defective blade.

Hi all,

I inserting washers between the cam and part attaching the base, and aligned the blade as much as I could. Now the cut is much better. The kerf is a lot narrower than was before, around 3mm which is very near the 2.8mm stated on the blade. Also, the tendency of trying to pull to the side stopped. There are other things that I do not like in it, like for example, the laser and notch on the base are not exactly aligned with the blade path, and the zero degree mark of the base does not exactly reflect zero degrees. However, it is somehow usable now. Maybe I am expecting too much now.
I think I will eventually get a Makita.

Nice catch, and fix.

 

[dogdog]

The circular saw I got is Parkside, it is a brand sold by Lidl supermarkets. For DIY, they are good value for money, at least till this episode. Regarding the attachment of the saw body to the base/frame, it does not seem to have any screws or adjustments.

Don't think your particular brand saw is available here in the states. We have Lidl groceries store in some towns but mostly cheap stuff and fresh produces. so... maybe it was dropped it and skews that cast aluminum frame out of square ? dunno. By adjustments I was referring to the same thing you are doing inserting a washer to try and realign the saw motor to the frame. It was not a common thing to do even for the cheapest $20 circular saw here... but they do sell different thickness shims, if you are able to find it in your country.

 

[Mike65]

What I do is cut the large sheets of plywood down to a more manageable size a little larger than what I need with a circular saw, then do the final cut to the size I need on my table saw. I do it that way because of space restraints in my small basement woodworking shop & it makes the plywood easier to handle on the table saw when it is not a full sheet.