DW7491 table saw not maintaining blade height

[D Angst]

Dewalt 7491 Table saw blade height not staying where set when in operation. I’m trying to cut a dado and when the saw is in operation, the blade creeps down and I cannot cut an accurate dado. I can watch the hamdwheel turn on its own due to vibration. 
Is there an adjustment to ‘tighten’ the screw to prevent this from happening?

Thanks in advance

[Eric - TIA]

Great question.  We were just talking about that with another saw.  There has to be something and we were going to check next week with the saw we are working with.  I don't have the Dewalt in front of me, but wondering if there is a cap on the middle of the handwheel that can be taken off and tighten.  Not sure if that will just tighten the handwheel or fix the problem.

[helg420]

D Angst, you guys find a solution to this? i have the same saw and have the same issue when cutting a dado. Thanks!

[Eric - TIA]

No, couldn't find anything but would love to know what is causing that.

[SteveT]

Was there a resolution to this issue? Same saw, same problem. ☹️

[Andre]

I have not had the blade height wander but I am having a related issue.  The blade height on my DWE7491 is stuck at the maximum height.  This is a saw that only has about 60 minutes of use so corrosion should not be the problem.  Nevertheless, I sprayed WD40 on the two shafts and was able to get a little movement up and down.  I don't want to put too much leverage and was hoping someone has had a similar issue.  This happened after I was ripping some rock maple which is surprisingly dense.  The saw did not overheat or bind.

 

[Andre]

Finally got my blade to lower and now it will not raise.  Very frustrating.  Is there an adjustment screw that needs to be loosened?

 

[ARW3]

Started experiencing the same problem with blade height slippage today on my Dewalt DWE7491RS table saw that I've had for about two weeks.  Nothing in the manual regarding blade height adjustment.  I lower the blade to the lowest setting, raise it to the height I need, start the saw and can watch the height adjustment handle slowly turn counter-clockwise thus lowering the blade.  No dust on the gears underneath as it is basically new and I don't see anything else that can be tightened really.  Called the Dewalt number on the manual, but of course, they're closed and now I get to waste my weekend not getting any work done.  Would love to know if this is just a faulty unit or if there is an actual fix.

[glass]

There is a solution. Buy a Makita 

[RobInNC]

I recently bought the DWE7491RS table saw as well, and put my dado blades on this morning to make some cuts for cabinets I'm making. Had the same issue with the blade height dropping. It took a couple of calls, but found the answer! The Dewalt factory service techs were outstanding.

 

The height adjustment knob is attached to a horizontal rod that connects to a vertical rod under the table top with a pair of sprockets (or pinion). Immediately below that pinion on the vertical rod is a nut. Tighten that nut with a 17mm wrench a bit while holding the height adjustment knob. Don't over tighten, or the knob will be difficult to turn.

 

That took care of it.

[Eric - TIA]

Awesome, thanks for sharing and glad the techs helped out.

[UncleJimmy]

I had the same problem. Thanks RobInNC

[EDP56]

I have the same issue with maintaining height adjustment. I reported the problem to Dewalt. They want me to check that all linkages are tight under the table. I have heard that this problem is common with contractor saws due to high vibration levels.

[EDP56]

Thanks RobinNC. I will try that. Dewalt helpline were not overly helpful. 

[P Gore]

You guys are amazing... I thought I was going crazy not able to get my 3/4 inch dado for a track install on a sled....what am I doing wrong I said, maybe wood working isn't for me I said, then I just turned the saw on and stood back and watched... wheels go round and round, round and round. Bet if I let it go for 10 minutes the bland would be beneath the cutting top..... I'm off to my tools to find a suitable wrench.

 

 

[ToolBane]

Dewalt table saws get rave reviews and for good reason. They would be high on the list if my current table saw were to kick the bucket. A lot of tradespeople use them daily for years and are very happy with them.

[susb8383]

On 6/11/2021 at 10:55 AM, P Gore said:

You guys are amazing... I thought I was going crazy not able to get my 3/4 inch dado for a track install on a sled....what am I doing wrong I said, maybe wood working isn't for me I said, then I just turned the saw on and stood back and watched... wheels go round and round, round and round. Bet if I let it go for 10 minutes the bland would be beneath the cutting top..... I'm off to my tools to find a suitable wrench.

 

 

Same here! This is my first attempt at a cabinet and I calculated everything out so carefully, but then when I cut my dados the panels didn't fit together as expected. Kind of forced them together but then when I tried to cut the tenons on the door rails it just wasn't working. I got the tenon on the test piece to fit perfectly but they wouldn't fit when I cut them on the actual rails. Then I watched the wheel slowly turn and the light bulb went off.

This fix worked, thanks so much!!

[M Hays]

I am having the same problem with a brand new DEWE 7485. I was making some staggered slit cuts for fingers on the corner of a box. Every time I move over and make a new slit the height keeps decreasing. I read the previous thread and when I turn my saw over I do not see a similar 17 mm nut to tighten the vertical rod. There are no nuts or screws or adjustments of any kind that I can see to help increase the tension. Has anyone found a solution on the 7485 model?

[TonyB]

Thanks for the tip. I was looking at that nut thinking that might do the trick, and sure enough, it worked great! Better to have some tension and have to use a little muscle to adjust the blade height than to have the blade move while using the saw!