Help, sawing straight

[Ivan Vegvary]

Using a Makita battery operated circular saw. Very happy with it for the last 5 years. Trying to make a long (8 foot) sawing guide. Using a 1"x 1/4" slat as the fence, secured to 7/16 inch thick plywood. Slat aligned with a 7 foot aluminium (extremely straight) extrusion. Two problems.

1. When I try to pass the saw along the fence with the blade about 3-4 inches from the fence, I can only saw about 7-8 inches before it becomes humanly impossible to push the saw forward. I'm a big guy, I can push 80-100 pounds.

1. When I pass along with the saw flipped (blade 1-1/2" from the fence) it is impossible to keep the saw plate against the fence. A gap of approximately 1/8" develops no matter how hard I try.

What am I doing wrong? Has anybody run into this. I've used this saw for thousands of cuts, but always cross-cuts, or, simply following a line by eyeball. This is the first time I've cut along side a fence.

All suggestions appreciated. Thank you

Ivan Vegvary

[Electric Comet]

what is the blade diameter

may be that it wanders and is not stiff enough

maybe you should plunk down 1000 bucks for an uncle festool

have seen some nice and somewhat affordable track saws for around 100 or 120 or thereabouts

[Leon]

Your blade is not parallel to to the saw shoe rdges. I would say it is toed in toward the wider section of the shoe.

I am not sure if this can be adjusted with that saw.

To make this work you need to set the saw on a small sled to index against you fence instead of the saw shoe/base. You will also need to be able to adjust the minute angle that the saw sets/attaches to the sled.

[Leon]

To confirm this, unplug the saw, expose as much of the blade as possible and then mark the front most tooth with a Sharpie. Then measure the front most tooth, to the edge of the saw shoe. Rotate the blade so that the marked tooth is at the back of the saw and make the same measurement. If the measurements are not "precisely" the same you have found your problem. The blade absolutely has to be parallel to to the fence reference.

[Puckdropper]

Leon wrote in news: [e-mail]:

It might not hurt to do this with a second tooth, say 90 degrees away from the first. If your blade is flat and your arbor is running true, you'll get the same readings.

I think Leon's on the right track with the blade not being parallel to the fence, but in the back of my mind is the possibility of a bent blade.

Puckdropper

[OFWW]

Ivan, I agree with Leon in that the problem is your saw. Make sure the saw blade is attached properly, take it off and put it back on, with everything cleaned. Then make sure it does not wobble when you physically manhandle the blade. (like for worn bearings. Up/down, sideways.

Then check to see if your blade is parallel to the foot of your saw. Measure each end to the opening parallels to it. Sometimes you can loosed and realign the foot. Then check to see if the blades is parallel to the outside edges of your saw.

Hope this helps.

[Leon]

I think because he is getting the exact opposite effect when using the opposite side of the saw it pretty much insures that the blade alignment to the shoe is the issue.

BUT NOW, it could be a number of issues if he forced a narrow kerf blade into submission. The blade is probably warped now, too.

[Leon]

One more suggestion. ;~)

[Ivan Vegvary]

last 5 years.

e fence, secured to 7/16 inch thick plywood. Slat aligned with a 7 foot al uminium (extremely straight) extrusion. Two problems.

ches from the fence, I can only saw about 7-8 inches before it becomes huma nly impossible to push the saw forward. I'm a big guy, I can push 80-100 p ounds.

t is impossible to keep the saw plate against the fence. A gap of approxim ately 1/8" develops no matter how hard I try.

r thousands of cuts, but always cross-cuts, or, simply following a line by eyeball. This is the first time I've cut along side a fence.

Thank you everybody. Did check for blade parallel to shoe. Exactly 3-3/8" on both ends of the b lade using same tooth. Checked the blade on my granite surface plate. Abso lutely flat. Blade is extremely thin and ve.....eerey old. Will buy a new 6-1/2" blade tomorrow with a wider kerf. Hopefully that will solve the p roblem. Otherwise I will go to my ancient Skill Worm Drive saw. It's amaz ing how much heavier everything gets after 25-30 years of ownership! It wei ghs a ton. No way would I ever try and cut with it while 'out of position' . Can't handle it at my age (74). Thank you again, Ivan Vegvary, Oregon

[DerbyDad03]

Have you checked for parallel between the blade and the edge of the base?

It sure sounds like they are not parallel. If they are not, the blade will win every time.

[DerbyDad03]

Whoops, sorry, late to the game. For some reason I didn't see all the other posts. Strange.

[Puckdropper]

Ivan Vegvary wrote in news: [e-mail]:

Sounds like the saw is ok, did you check the fence? It might be worth a test cut with a 2x4 fence to make sure the fence isn't flexing on you.

Puckdropper

[nailshooter41]

You have plenty of good advice, and all of it I certainly agree with. So t hese are just a couple of more thoughts.

I use straight edges to break down material and the circular saw/straight e dge combo was the preferred job site method from the time I started. Still it isn't perfect.

I found on my older saws that they lined up parallel as needed, but once sw itched on they fell out of alignment. This happened on my saws that had sl eeve bearings at the arbor blade side, not roller bearings. Of course, whe n the roller bearings wore, they would do the same thing. So measuring the saw revealed nothing, but using it did.

Out of balance saw blades that appeared true and flat, but when whirling at 5K+ r.p.m.s, it made it difference.

Last, and the hardest for me to find the first couple of times was the shoe of the saw wasn't clean. It would pick up a bit of adhesive, some wood re sin, or even a small gouge in the sole plate and that would turn the saw. Now I check the sole plate and the blade guard point that rides on the wood and clean or polish them up with 220gr sand paper as needed before cutting along a straight edge.

Robert

[Scott Lurndal]

I would guess that the blade is not parallel to edge of the baseplate.

[94hwtkaschper4x]

last 5 years.

e fence, secured to 7/16 inch thick plywood. Slat aligned with a 7 foot al uminium (extremely straight) extrusion. Two problems.

ches from the fence, I can only saw about 7-8 inches before it becomes huma nly impossible to push the saw forward. I'm a big guy, I can push 80-100 p ounds.

t is impossible to keep the saw plate against the fence. A gap of approxim ately 1/8" develops no matter how hard I try.

r thousands of cuts, but always cross-cuts, or, simply following a line by eyeball. This is the first time I've cut along side a fence.

Sounds like the edge of the saw base is not parallel to the blade, pulling tight one direction, and wandering away in the other. Not sure whether ther e is adjustment built in, or if you need to either fab a suitable wedge, or otherwise grind/trim the sides to be parallel. I have no experience with y our issue (or a Makita saw), so these are no more than pure guesses/suggest ions... Good luck

[94hwtkaschper4x]

Some suggestions here:

[Leon]

One other thing I have witnessed many years ago. A thin kerf blade on a saw like this can warp from heat. I have seen one warp and stay warped until it cooled, as it cooled it suddenly popped back flat. I just happened to be looking at the blade when it did that.

Oddly while it was still relatively hot I could easily wiggle it from warped to flat and it would stay which ever way I left it. Once it cooled it popped back to and stayed flat.

[krw]

Before I had a track saw I made a "fence" by fastening a ~3" strip of MDF down to a ~12 strip. the 3" piece as the fence to cut the 12" in the right spot. The whole thing is pretty rigid - not much flex. I still use it if I can't clamp the track down like a floor).

[Doug Miller]

Leon wrote in news: [e-mail]:

[...]

I don't think so. I think the teeth on one side of the blade are dull, probably from hitting some foreign object.

[John Grossbohlin]

Leon wrote in

This is a plausible explanation... I'd also add that I've used circular saws that had a lot of end-play in the shaft such that the blade moved away from the motor as I ran the wide side of the shoe down a straight edge. One of those saws (Sears or Black and Decker??) led me to buy my first Porter Cable tool...