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View Grumpymike's profile

flat bottom dado

by Grumpymike
posted 688 days ago


32 replies so far

View knotscott's profile

knotscott

5374 posts in 1981 days


#1 posted 688 days ago

Both of the dado sets you mentioned are considered to be pretty good sets. It could be your saw….what saw do you have? Some of the TTI/Ryobi made Craftsman and Ridgid contractor saws are known to have miscut arbors that cause problems with dado stacks.

-- Happiness is like wetting your pants...everyone can see it, but only you can feel the warmth....

View Dennisgrosen's profile

Dennisgrosen

10850 posts in 1721 days


#2 posted 688 days ago

no its not you that is the problem its just the way the dado is made on a tablesaw
if you get a handrouter in iron or wood your problem will be solved in a snap
since you can get a dead on flat bottom with that and with the correct debth all the way
some call the router … granny tooth

Dennis

View BinghamtonEd's profile

BinghamtonEd

1204 posts in 975 days


#3 posted 688 days ago

I have the Freud 8” stacked dado set, and I get some marks when cutting tenons wider than the width of the dado, due to the slight bat-ear cut on the outside of the outer blades and having to make multiple passes, but my chippers leave pretty even bottom. Every once in a while I will see some variation, but not on the order of 1/32 to 1/16 like you’re seeing.

I would ask if your chippers had been sharpened, but it looks like you bought the set new. Do they fit, without any play, on the arbor? If you know somebody with a dado set that does not have the same issues as you, you could swap sets and each do a test cut, that might tell you if there is an issue with your saw.

-- - The mightiest oak in the forest is just a little nut that held its ground.

View BinghamtonEd's profile

BinghamtonEd

1204 posts in 975 days


#4 posted 688 days ago

Dennis, I would agree that a table saw isn’t going to leave the same cut as a router or plane, however I don’t think a 1/16” difference between chippers should be considered “just the way the dado is made on a tablesaw”. If my Freud set gave me that, I’d be returning it.

-- - The mightiest oak in the forest is just a little nut that held its ground.

View knotscott's profile

knotscott

5374 posts in 1981 days


#5 posted 688 days ago

It sounds to me like its far more than just the nature of dado made with a TS. Many of us get such good results with a TS, that it’s debatable which is the preferred method…TS or router.

These cuts were made with 4 different stacked dado sets on a TS…3 of them are sub-$100 sets:


-- Happiness is like wetting your pants...everyone can see it, but only you can feel the warmth....

View Dennisgrosen's profile

Dennisgrosen

10850 posts in 1721 days


#6 posted 688 days ago

Bingham
I don´t have a Ts and we ain´t alowed to use dadoblades here in europe
I just saw a videoclip on ( I thoink it was woodwisper ) that shows
how the sheet tend to be liftet a bit from the table so you don´t get
the same debth trugh the cut thats why I thought of the old router :-)

if its chiping out from the dado and into the sheet ….. I wuold use a scoringblades
infront of the sawblades if the Ts can be updated with them
or score the dado with a knife before I cut them

Dennis

View BinghamtonEd's profile

BinghamtonEd

1204 posts in 975 days


#7 posted 688 days ago

Dennis, you’re very right about the piece lifting with the dado set. When I first got my set, I had sloppy looking tenons because I did not maintain pressure over the cut. With just a little downward pressure though, they turn out well. Featherboards work well when cutting rabbets with the dado set. Good tip with scoring the dado, too, that works well also when using a router (electric, never used a hand router).

From my experience (however brief), chip-out has not been an issue on the TS except at the trailing end of the dado as it exits the workpiece, and a sacrificial fence helps that a lot.

-- - The mightiest oak in the forest is just a little nut that held its ground.

View Dennisgrosen's profile

Dennisgrosen

10850 posts in 1721 days


#8 posted 688 days ago

I think it was when making Dado´s in plywood he talk about scoring the dado

Dennis

View teejk's profile

teejk

1208 posts in 1290 days


#9 posted 688 days ago

I’ve had a Delta 8” set for 8 years (on a Delta saw)...never had a problem unless I used a spacer (that stands to reason and I expect it…quick clean-out with a chisel).

I read here quite often about sloppy arbors where the inside blade can run high. That is one issue that I don’t have.

If you are stacking the chippers properly and you know you have a good perp from table to blade, the fact that you have run through a few sets tells me that you have a poorly machined arbor on your saw.

View Alexandre's profile

Alexandre

1417 posts in 797 days


#10 posted 688 days ago

I have a freud dado set. It is a good set.
You probably have a bad arbor.

-- My terrible signature...

View muleskinner's profile

muleskinner

663 posts in 1042 days


#11 posted 688 days ago

Grumpy, I know exactly what you’re talking about. It’s not you. It’s not the dado set. It’s your saw arbor. I wouldn’t say you have a bad arbor, it might be just the way it is. I had the same discussion a few weeks back. http://lumberjocks.com/topics/39853

-- Visualize whirled peas

View teejk's profile

teejk

1208 posts in 1290 days


#12 posted 688 days ago

binghampton…I forgot to mention…due to a stupid thing I did with the TS a few years ago (where I got a new found respect that I think will stay with me until I die), I borrow the jointer push pads when I do dado work now. They allow me to apply some downward pressure on the cut and they are cheaper than band aids and blood cleaning solutions. I guess when you think about it, the concept of running a jointer is the same as running a dado on the TS.

View Grumpymike's profile

Grumpymike

1023 posts in 921 days


#13 posted 688 days ago

Wow what a response!! First lets see if I can insert some photos, first is the arbor, I have laid a streight edge on it to see if it was indeed streight … appears to be OK. Well been at this for some time now, can’t seem to figger out how to get photos inserted here.
Let me answer some questions:
It is not chipping out the sides, the bottom is uneven like each chipper blade is a different size.
This is a new set never sharpened or resharpened I should say.
The TS is a Rigid 2424. The stock is not lifting off the table, I use a fingerboard on the fence to hold down.
If I could get dados like Knotscott shows I would be happy as a pig in mud!! And if I could get photos to show up here I’d show what I mean … I’m just not much of a computer guy, the G-Grandkids will be here in a few weeks maybe they can show me how.
I will contact Rigid to see if they can send a new arbor, this thing has a lifetime gaurentee. Lets see if they stand behind it??
Thanks to everyone for their help.

-- Grumpy old guy, and lookin' good Doin' it. ... Surprise Az.

View Grumpymike's profile

Grumpymike

1023 posts in 921 days


#14 posted 688 days ago

Oh wow the photo showed up, now I will post the rest … By god this is a great day we have killed another giant … I got the computer to post a photo … Wheeeha!

-- Grumpy old guy, and lookin' good Doin' it. ... Surprise Az.

View knotscott's profile

knotscott

5374 posts in 1981 days


#15 posted 688 days ago

LOL…congrats on your pics!

It does indeed look like you have a miscut arbor. Getting a properly cut arbor is a solid fix if they’ll send you one, and if you’re up to it. I have heard of folks filling that miscut thread with JB Weld, and claiming good results….it’s not as elogant, but for $3, and 5 minutes of effort, it might do the trick. You can search the Ridgid forum for more info.

-- Happiness is like wetting your pants...everyone can see it, but only you can feel the warmth....

View Jim Jakosh's profile

Jim Jakosh

11099 posts in 1711 days


#16 posted 688 days ago

If I have the need for a great looking front of the dado, I use the router to cut it. However for fitting shelves into sides where I usually cover up that front of the dado with a trip piece, I use a Craftsman wobble dado. I have had mine for over 40 years and it cuts flat bottoms. A friend of mine bought 3 or 4 of them from different manufacturers and none would cut a flat bottom. I’m afraid to every get this one sharpened because I think they’ll screw it up!! I have it set up on my Craftsman RAS and that is dedicated to dados only!

I have had very good luck cutting rabbets and dados on the table saw by carefully dialing in the width and depth of cut with a dial indicator. I used to rabbet with the router, but now I go for the table saw first.
If you skip to far each cut, you have a little wood to clean off the bottom with a chisel….....Jim

-- Jim Jakosh.....Practical Wood Products...........Learn something new every day!! Variety is the Spice of Life!!

View muleskinner's profile

muleskinner

663 posts in 1042 days


#17 posted 688 days ago

Grumpy, try this – put one of your blades on the arbor hard against the back washer. Try to move it up and down to see if there is any slop between the blade bore and the arbor. Now slide it out onto the threaded portion of the arbor and repeat. I found a .002 difference on mine and I had exactly the same snaggle-tooth dadoes. I put the stack on my RAS which has a straight cut arbor and had smooth bottomed cuts.

-- Visualize whirled peas

View Grandpa's profile

Grandpa

3057 posts in 1281 days


#18 posted 688 days ago

When cutting threads on a lathe you run to the shoulder then stop the feed and then back the tool out. This leaves what is called an under cut. This is much like what we see in your photo. It is a simple way of keeping the tool from hitting the shoulder and causing damage to the tooling. This arbor might have been made that way. It does look like it has been hot in that area. I am wondering if at sometime a blade or chipper has stopped turning and the arbor was able to continue turning causing this to heat up. In any case it looks like you need a new arbor. This is not going to heal itself and you will not be happy no matter how many dado sets you buy. JB Weld might do the trick. I would try it first. Like the Scott said $3 and 5 minutes will tell you if it was worth the effort.

View BinghamtonEd's profile

BinghamtonEd

1204 posts in 975 days


#19 posted 687 days ago

Teejk, I’m with you on the push pad. I use a long push pad (maybe 12-16”) with handles on either end. That allows me to put pressure where it needs to be, without having my hands anywhere near the cut.

If you can remove the arbor it would make repair pretty easy (could still do it in place, but might be difficult to get to). Like others have said, fill the recess with JB weld, and file it smooth. You say that it looks like each chipper blade is a different height, from the pictures it looks like your only problem area is that first chipper, the one that would end up sitting on that slight recess in your arbor, giving it some play. The rest of the dado looks fine to me.

-- - The mightiest oak in the forest is just a little nut that held its ground.

View Grumpymike's profile

Grumpymike

1023 posts in 921 days


#20 posted 687 days ago

Good morn’in
now I see the problem on the arbor. Yes there is a “void” at the end of the threads that could let that second balde (chipper) be a bit ofset and now it would stand proud of the rest causing the uneven dado. My photo cought the problem and I didn’t know that I was looking right at it all along. ...
I will try the JB Weld first, then see if Rigid will make an adjustment on the replacement arbor or what.
I can’t thank all of you enough for your help.
I will add that Teejk and Binghamptoned are right about using the jointer pads, I use the feather boards in the ‘T’ slot on the rip fence and use the push pads to feed the board across the cutter. I have this fear that the board will shatter and leave my hand to deal with the spinning cutter … (shrug and shutter) ... just my phobia.
Thanks again,

-- Grumpy old guy, and lookin' good Doin' it. ... Surprise Az.

View BinghamtonEd's profile

BinghamtonEd

1204 posts in 975 days


#21 posted 687 days ago

If you’re thinking about asking Rigid to provide you with a new arbor, or assistance in purchasing one, you may want to contact them before you try the JB weld. They may be more likely to work with you if you haven’t tampered with the arbor yet.

-- - The mightiest oak in the forest is just a little nut that held its ground.

View johndale's profile

johndale

9 posts in 688 days


#22 posted 687 days ago

dennis—why can’t you use dado blades in europe?

View Dennisgrosen's profile

Dennisgrosen

10850 posts in 1721 days


#23 posted 686 days ago

John its forbidden and therefor as I know of not able to do so
in the olddays the goverments/ factory´s in europe thought they where too dangerous
and the same job can be done just by making more passs with a single blade
and since the market isn´t there …. = no dadoblades in the stores if you are lucky
enoff to have a US made saw

Dennis

View teejk's profile

teejk

1208 posts in 1290 days


#24 posted 686 days ago

not to be cynical…but do you use real wood in Europe anymore? I lived there for years and it seemed that IKEA owned the market.

View Dennisgrosen's profile

Dennisgrosen

10850 posts in 1721 days


#25 posted 686 days ago

Teejk
:—))) don´t be too snoppy there is quite few Ikea´s in US too
but since Ikea developed the flatpacket furniture system only those who
earn more money than they can spend can afford wooden furnitures ….. nearly

not quite so yet but realy lots of furniture masters have shot down since then
and the highend designer stuff is also made on factorys though by very skilled craftmen

another reason is people wants to change stile /colours in there home about every ten years
and think why spend 5000 – 15000$ on a dinningtable with chairs when they can buy it for under 500 $
and a few hours of labor at home = no demands for furniture grade lumber on the shelfs
in the local lumber suplier :-(

Dennis

View teejk's profile

teejk

1208 posts in 1290 days


#26 posted 686 days ago

I hear you Dennis…in the US we live in a “throw-away” society so IKEA’s particle board stuff is enough for many people. And then you/we have that “green” thing…people think they are saving the planet by using saw-dust (forgetting about the energy/chemicals needed to produce it into furniture).

View Dennisgrosen's profile

Dennisgrosen

10850 posts in 1721 days


#27 posted 686 days ago

by then you say those green thinkers are woodworkers too

first cutting a tree in to small pieces and then glue it together again ….in the wrong ordrer
that we are smart enoff to call clever designet woodworking ….. LOL

Dennis

View teejk's profile

teejk

1208 posts in 1290 days


#28 posted 686 days ago

Dennis…I guess we are losing woodworkers here as well…I see it in my sons…not a “pro” shop by any means (although I did treat myself to a dedicated 30×40 shop with radiant heat) but they don’t have any appreciation for turning raw wood into something they can point at. I guess anybody they would show it to wouldn’t notice either. Rather sad I think but I still would rather be in my shop than in the house.

View Dennisgrosen's profile

Dennisgrosen

10850 posts in 1721 days


#29 posted 686 days ago

only the time will tell if you have prepped him enoff :-)
but see if you can learn him the pleasure of hearing a sharp plane
singing when used on wood and the silence between every shave it produce

then there is a chance when has grown to be a man he will walk the path of woodworking

I´m still only a novice myself but can remmember it was to use my first coffeetable and relaxing chair
I made in the primeryschool
now I restore old tools with the wish to get that feeling again after only have been doing diy work
a few decades :-)

Dennis

View Grumpymike's profile

Grumpymike

1023 posts in 921 days


#30 posted 664 days ago

Well guys here is the bottom line:
After some phone calls and a bit of pleading, Rigid came through … I now have a new arbor inslalled by Rigid at no cost to me whatsoever … I did have to deliver the saw to their repair station (about 20 niles away) and pick it up three days later, but it was all FREE
now I have flat bottom dados. Thank You Rigid and thank you LJ’s for the input.

-- Grumpy old guy, and lookin' good Doin' it. ... Surprise Az.

View knotscott's profile

knotscott

5374 posts in 1981 days


#31 posted 664 days ago

Super! That’s the outcome we all like to hear about. Thanks for the update.

-- Happiness is like wetting your pants...everyone can see it, but only you can feel the warmth....

View Dennisgrosen's profile

Dennisgrosen

10850 posts in 1721 days


#32 posted 664 days ago

thanks for the update Mike .-)

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