Woodworking Talk banner

Big problem with Dado cut...!!

11K views 41 replies 21 participants last post by  DrRobert 
#1 ·
I'm using my dado blades for the first time, and they're not cutting cleanly.

I have a MIBRO set and not sure what the problem is - if it's the blades, the installation, the technique or the wood?

I have installed 1 blade + 1/8 spacer + 1/8 spacer + 1 blade = 1/2" total

Here's a picture of the problem:



Notice the chipping of the wood?

When I push the piece across the blades, chips and splinters fly everywhere!

Please help - I need this for my newest project

Sorry for the picture size but I wanted to make sure the cut was visible.

Thanks as always in advance
 
See less See more
1
#5 ·
From what I can see it doesn't look half bad. I've had dado sets where you could see where every single chipper cut. A dado set on a table saw doesn't cut as smooth as a router bit. You just can't expect the same cut.
Steve,

Are you saying that splinters and chips are normal for a dado cut?

That's not very promising LOL....

Here's the same cut using my single blade back forth dozens of times

 
#9 ·
That's my suspicion as well @GeorgeC - I can't believe that a dado is going to be sending splinters everywhere and that is normal for this type of cut.

I just ordered a new set - Freud SD208 8-Inch Professional Dado

I'm hoping it's the Mibro bade set I got - it was a Harbor Freight purchase last year.

I also didn't mention, when I use the blade TS shakes and makes a god awful noise like it's going to fall apart. I've tightened the blades, reset them and it doesn't change.

My TS is pretty sturday (Delta 36-725) - with my regular blades it's very quiet and works really well but this Dado set scares me :(
 
#10 ·
Also, I consider a 1/8” spacer very wide. There are chippers that are 1/8” wide.
The ends of the blades can overlap but must be staggered so the tips don’t touch each other.
Usually the spacers are less than 1/16”.
Score the line prior to the cut as suggested above.
Use a clamp on the Miter gauge if needed to hold tight on the line. (I see a wavy line in the picture).
 
#15 ·
sure do appear to be carbide tipped - and not a lot of tips.... i.e. cross cutting with a 30(+/-?) tooth blade....and the 'interior' blades being two tooth . . . I would expect a fair amount of tear out.

the shoulders should have been cross cut to depth using a finer tooth cross cut blade, then the rest hogged off.
 
#22 ·
Here We go....



So I got the Freud a day early and re-dadoed the legs on my table.

First heres the scoop - I think either the Mibro or the Freud blades are back wards.

If you compare the 2, the Freud blades face away from the front of the saw where the Mibro face towards the saw:



The Freud is much quieter and doesn't shake my TS like it's falling apart:



Here are the after cuts once I installed the Freud

This is the Freud cut:


And this is the Mibro cut



While there was a very little bit of chipping with Freud (cross cutting) - it wasn't anywhere near as bad as the Mibro - I was ducking for cover with that one LOL

So, I'm keeping the Freud and selling the Mibro

Kind of weird about the blades though isn't it?
 
#27 ·
I have a different model Freud dado set so you will need to check yours carefully. If I remember correctly, on mine, there is a left outside blade and a right outside blade. The teeth are milled to create a splinter free, flat bottom dado, so it is important to mount the outside blades in the correct position and rotation according to the instructions.
 
#29 ·
In your picture, the Freud blade on the right goes on first, the one on the left goes on last, with the printing facing the nut. On the Buzz blades, the one on the left goes on first with the one on the right going on last, also with the printing facing the nut.


In woodworking there is always more then one way to accomplish something.
 
#31 ·
I'm not all that familiar with dado blades, having only an old Craftsman steel set--which, for what it's worth, actually cuts fairly cleanly. (that being said, I use a router for dadoes).

All that being said, the Mibro blades look like regular TS saw blades that are packaged together with spacers and relabeled for dado use.
 
#34 ·
I have a relatively new Freud Dado set (NOT Diablo). Although the stacking arrangement is in US Standards, I believe the Dado set is in Metric equivelant. The reason for my thinking is that the dados I make, normally 1/2" and 3/4", are slightly undersized. This was first brought to my attention when I started using it and noticed that the 1/2 and 3/4' dado slot fit my plywood perfectly. Normally there is a noticable gap between the dado and the actual plywood. I REALLY love it for that reason - no oversized dados. If I need exactness, there are sufficient shims to do that.

BTW, I just noticed this is a 4 year old thread.
 
#35 ·
I have a relatively new Freud Dado set (NOT Diablo). Although the stacking arrangement is in US Standards, I believe the Dado set is in Metric equivelant. The reason for my thinking is that the dados I make, normally 1/2" and 3/4", are slightly undersized.
You are correct. The Freud Dado sets are not accurate according to their own charts. They are metric.

The diameter of the blades is not really 8 inches, either. They are 200 mm (7.87 inches), which is just enough smaller to cause problems for SawStop owners, especially the jobsite saws, which do have have a blade diameter adjustment screw.

See my posts in this thread, where I complain about the difference between Freud's dado chart and the actual measurement. Simply put, the chart is inaccurate, probably to avoid discouraging US customers when they learn that they need shims for exact standard measurement cuts:
 
#36 ·
@Tool Agnostic
David, I actually did call Freud Tech Support (or whatever they are called) several months ago. The guy I spoke to said he was unaware of the what I was talking about. I have not made any box joint jigs yet as I haven't needed them yet. You, on the other hand, will have to make new ones.
I like the way it is working out for me with the plywood as I have done small mods for other RVers in the park. I also have a Freud blade for my table saw. Haven't checked that only because I haven't had the need yet. If it is not leaving exactly 1/8" kerf, THEN I will have an issue with them. I like pinstripes in a lot of my stuff. My pinstripes are always 1/8". Often times I cut my 1/8" strips on the left side of the blade using the tape on the TS fence and advance it over 1/4" at a time leaving me with 1/8" pinstripe with a 1/8" kerf. Simple measuring system
 
#37 ·
@Tool Agnostic
David, I actually did call Freud Tech Support (or whatever they are called) several months ago. The guy I spoke to said he was unaware of the what I was talking about. I have not made any box joint jigs yet as I haven't needed them yet. You, on the other hand, will have to make new ones.
I like the way it is working out for me with the plywood as I have done small mods for other RVers in the park. I also have a Freud blade for my table saw. Haven't checked that only because I haven't had the need yet. If it is not leaving exactly 1/8" kerf, THEN I will have an issue with them. I like pinstripes in a lot of my stuff. My pinstripes are always 1/8". Often times I cut my 1/8" strips on the left side of the blade using the tape on the TS fence and advance it over 1/4" at a time leaving me with 1/8" pinstripe with a 1/8" kerf. Simple measuring system
Hi Tony - You make good points. They make me want to check the kerf width of the full kerf Freud Fusion blade I have.

I find it stunning that Freud technical support claims that they are unaware of the issue with the dado stack. I call BS on that. There are reviews on Amazon and elsewhere from others complaining about the same issue. A Freud technical support engineer who didn't know about must be living and working in a deep mine on a deserted island. Did you see my post #13 in the thread I mentioned? I posted my letter that I wrote to Freud tech support along with their response. See this post with the letters:
https://www.woodworkingtalk.com/thr...-dado-stack-and-1-64-inch.220127/post-2139463

Note that I don't have to make a new box joint jig as long as I am willing to use shims to size my dados to a perfect 3/8 inch.

Confession Time:
The Freud stack was getting old and I vowed not to resharpen that cheap set, so I bought a Ridge Carbide dado stack recently. Besides, I wanted to see if I can get better cuts with four wing chippers rather than the two wing chippers in the Freud stack.

I have not used the Ridge Carbide dado stack yet. I continued to use the Freud stack because I was working on "junky" projects such as softwoods and reclaimed wood (for shop projects, etc.), reserving the Ridge Carbide stack for the "true" fine woodworking projects, whatever that means. I haven't had a chance to test the Ridge Carbide to confirm that they make true standard measurement cuts without shims, but that was my belief when I bought it.
 
#38 ·
@Tool Agnostic
I hadn't noticed your earlier posts but I did press the link. Very interesting to say the least. I'm going to stick with the Freud because of the plywood thing. I did think it was strange that the Tech Support guy said he was unaware of it. I just chalked that up to the possibility he was a new guy.
And.....your post was highly educational. Enjoyed it
Thanks
Tony B
 
#39 ·

This is the set I bought and pricy but cuts beautiful every time
 
#41 ·
https://www.infinitytools.com/dadonator-stacked-dado-blade-set-with-5-8-bore
This is the set I bought and pricy but cuts beautiful every time
I have a newfound respect for Infinity Tools after I complained about some design issues in one of their products. They joined WoodwokringTalk and responded. A short time later they redesigned the product. The updated design addressed all of my concerns and more. I am very pleased with the new version of the product. It was an impressive display of great customer service.

I bet that dado stack cuts beautiful.

For myself, I considered the Infinity Tools dadonator set, too. Unfortunately, it has solid body chippers and depth limiting shoulders behind the carbide tips. Solid body chippers and blades with depth limiting shoulders are not recommended for SawStop table saws.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top