Wandering miter cuts on Dewalt 716 (12" in saw) Urgent...

[Pete Street]

I have to do a bunch of 45 degree miter cuts in 5/4 cedar for some heavy base trim I milled.

I'm having bad problems with wandering cuts..not unusual.

I  need the 12" saw because the trim is too high for a 10" saw..

Driving me nuts..the saw seems set up pretty well..

I replaced the stock blade with what I thought was a decent Diablo..doing the same thing as the stock with a bit of improvement

Wondering what luck you guys have had with nice, heavy, quality blades and miter cuts?? Need help ASAP...thanks!!

 

[bobfog]

A photo of the result would be very beneficial. Else we're just guessing at what's going on. What exactly do you mean by wandering?

In generic terms, technique comes into it, ensuring you're allowing the blade to cut at it's own pace and your hand guiding the handle/blade through the cut rather than forcing it and causing deflection. Cedar is particularly soft so the blade shouldn't be having any problems cutting through it.

 

[Pete Street]

Bob,

I'll try get some pics..I have horrible internet - out in the country and using a hotspot..very touchy for anything but text.

I'm cutting the pieces upright..they are about 6" tall..It's a classic case of the cut going off on a slight angle..fairly consistent line. this does not occur on straight cuts..dead straight in all my tests.

I am clamping and waiting for the saw to hit top speed..going very slowly and not influencing the saw, best i can.

 

[bobfog]

Bob,

I'll try get some pics..I have horrible internet - out in the country and using a hotspot..very touchy for anything but text.

I'm cutting the pieces upright..they are about 6" tall..It's a classic case of the cut going off on a slight angle.

I am clamping and waiting for the saw to hit top speed..going very slowly and not influencing the saw, best i can.

Are you sure the pieces are perfectly flat and not cupped in any way?

 

[Pete Street]

They're pretty good Bob..I checked em..

I think it's the combo of a thin kerf, 59 dollar diablo blade and a 12 inch saw..When I replaced the stock blade with this one things improved a bit..but not near enough.

 

[bobfog]

They're pretty good Bob..I checked em..

I think it's the combo of a thin kerf, 59 dollar diablo blade and a 12 inch saw..When I replaced the stock blade with this one things improved a bit..but not near enough.

I'm at a loss as what to suggest, but in Cedar I would be surprised if even the cheapest, thinnest kerf blade wouldn't cut the thickness you describe. Cedar is extremely soft. One final thing I can think of is have you locked the sliding mechanism tightly in place to eliminate any slack/play and just tried cutting using the drop action of the blade?

 

[Pete Street]

Bob, It's not a slide saw..compound only.

And yes..Im dumbfounded that it's happening in Cedar..

 

[bobfog]

Bob, It's not a slide saw..compound only.

And yes..Im dumbfounded that it's happening in Cedar..

Ah apologies, I thought it was a slider. Ok well apart from a mechanical fault with the saw, i.e. a nut or bolt being loose and the head having some slop then I'm stumped.

 

[Pete Street]

I think it's blade wander...due to centrifugal forces and a crappy, unbalanced blade..??

 

[Michael Kellough]

"wandering cuts.."

As in an S curve or simply wider kerf at top or bottom?

 

[Pete Street]

Michael..It's a fairly straight line, off angle a couple of very noticeable degrees..and of course..the miters are useless

Now, If I use the compound part of the saw and lay the piece down flat..it's sort of curved..not S shape though..like the blade is doing some kind curve...

 

[TomE]

I presume this is for outside corners for the base trim?
If the walls are somewhat square try a sharper miter like 46°
Insides corners are usually best served by coping.
Can also try rough cutting then make a second final cut and keep the trim firmly against the fence and or table

 

[Pete Street]

Tom, outside corners on a whole bunch of cedar posts..

I've made the determination that there is something deeply wrong with this saw..I bought it a while back and used it for some framing..seemed fine...Still is fine on straight 90 cuts, dead on.

Now I'm noticing a huge warp in the main base and that the center disk (which rotates for miter work) changes it's pitch as it spins..made a bunch of measurements with straight edges and squares on a leveled concrete floor and this one is a total lemon..Im inside warranty but Dewalt tells me it would be a week and half to get it fixed,,Im thinking...fixed??? there are ten things wrong here..please replace..

...Im 105 miles from the nearest DW service center so Im basically screwed in this one..need to get another saw to finish this gig...uGh.

Bad day...

 

[bobfog]

Tom, outside corners on a whole bunch of cedar posts..

I've made the determination that there is something deeply wrong with this saw..I bought it a while back and used it for some framing..seemed fine...Still is fine on straight 90 cuts, dead on.

Now I'm noticing a huge warp in the main base and that the center disk (which rotates for miter work) changes it's pitch as it spins..made a bunch of measurements with straight edges and squares on a leveled concrete floor and this one is a total lemon..Im inside warranty but Dewalt tells me it would be a week and half to get it fixed,,Im thinking...fixed??? there are ten things wrong here..please replace..

...Im 105 miles from the nearest DW service center so Im basically screwed in this one..need to get another saw to finish this gig...uGh.

Bad day...

At least you got to the bottom of it.

I guessed (as I mentioned above) that I thought it would be a mechanical issue more than the blade deflecting in Cedar.

 

[Pete Street]

Indeed..wsa puzzle for me too..the Cedar issue. I've seen this plenty with harder woods in chop boxes using thin kerf blades..

I prefer a 10 inch saw with a heavy blade..pretty spot on for the most part..This stuff won't fit though.

In the end having a reliably level surface to troubleshoot on was key..everything became apparent. Not sure how this one made it past the inspector. I actually love the feel and ergonomic of this saw and friends feel the same way about it..We'll see what happens when i finally bring it in..

I appreciate the help and suggestions..

 

[peter halle]

A warped base like that will give you those results - especially if you are being economical with material and just trimming off an end for the 45.  The difference between the 90 and 45 results is due to the location of the cut over the warped table (closer to the valley = worse results.). My very first miter saw back in the 80's was returned for just that.

In a pinch and to get thru the job you might be able to place a wide piece of wood on the table that can't be cut all the way thru and see if that will support yur workpiece better.

Peter

 

[bobfog]

Indeed..wsa puzzle for me too..the Cedar issue. I've seen this plenty with harder woods in chop boxes using thin kerf blades..

I prefer a 10 inch saw with a heavy blade..pretty spot on for the most part..This stuff won't fit though.

In the end having a reliably level surface to troubleshoot on was key..everything became apparent. Not sure how this one made it past the inspector. I actually love the feel and ergonomic of this saw and friends feel the same way about it..We'll see what happens when i finally bring it in..

I appreciate the help and suggestions..

Hopefully you can get the saw fixed. If you do end up going for a new one, I guess the Kapex will obviously be a contender as you're on a Festool forum, but reliability is questionable at the moment to say the least.

I have the Bosch Glide 12" saw and I find it's the best of both worlds, large capacities, but with the right blade the unique slider design gives you the rigidity and lack of deflection of a smaller bladed saw.

 

[bkharman]

[member=58732]Pete Street[/member]

can you lay the trim down and cut through it with the saw on a bevel?  Not sure if it is possible, but even if it cuts through 3/4 of the stock without deflecting, and you have to cut the rest with a hand saw, it will be better than what you are contending with now.

Cheers.  Bryan.

 

[justinh]

Tom, outside corners on a whole bunch of cedar posts..

I've made the determination that there is something deeply wrong with this saw..I bought it a while back and used it for some framing..seemed fine...Still is fine on straight 90 cuts, dead on.

Now I'm noticing a huge warp in the main base and that the center disk (which rotates for miter work) changes it's pitch as it spins..made a bunch of measurements with straight edges and squares on a leveled concrete floor and this one is a total lemon..Im inside warranty but Dewalt tells me it would be a week and half to get it fixed,,Im thinking...fixed??? there are ten things wrong here..please replace..

...Im 105 miles from the nearest DW service center so Im basically screwed in this one..need to get another saw to finish this gig...uGh.

Bad day...

A warped base will present like that.  The 716 is my primary saw for trim.  The blade makes all the difference.  I won't run anything but a standard kerf. Makes a huge difference in that saw.  The vast majority of the problems people have with 12" saws are caused by thin kerf blades.  The arbor bushing on all DeWalt saws bends easily when you jam a cut especially with heavier blades.  You can feel it in the cut immediately. It's a $5 replacement part.  The fact that the inexpensive part bends is that it saves the arbor and the blade. I keep a few in the van at all times.