Regrettably, whilst the demonstration “looks” convincing it none-the-less pushes the boundaries of good engineering prudence. Yes, the demo went well- as far as it goes - but relying on just 2 to 3 threads to hold what is a relatively massive blade on to the arbor is indeed tempting providence! Sticking my neck out here, I would say, as a time served engineer and a qualified production engineer ( retired over 20 years ago) the minimum engagement of the nut on the arbor must be equal to the thickness off the nut; more if possible under trying conditions, like cutting tough timber on a major scale.
You're holding the blade on with about half a nut AND you're missing the washer that helps keep the nut from loosening. That's not sketchy; that's foolishly dangerous. Doing this will increase the risk of saw failure and the potential subsequent accident. How much of an increase? How bad of an accident? I' don't know and don't want to find out. richard --
I have a Dewalt 7491 and a Dewalt 8” dado stack. The dado stack works perfectly fine with it with full thread contact on the nut with the arbor bolt and blade collar.
Physical space is not necessarily the reason DeWalt states this saw is not compatible with a dado stack. There's also the limits of the motor to consider. It's far more stress on the motor to make a 5/8" cut than a 1/8" cut. Clearly it can be done as indicated in this video, but you could also be dramatically shortening the life of your saw. I have the DWE7485 model of this saw (2021) and there is a metal guard in the dust collection shroud that limits the width of what you can put on the arbour. Others in the thread have suggested the Freud box joint blade pair that support 1/4" and 3/8" cuts. On the 7485, you can only use the 1/4" option as the 3/8" option would result in the blade hitting the guard.
Shorten the life of your saw? Most electric motors can take an incredible amount of use and abuse. That's the last thing I would be worried about. Having the blades come off and hit me in the face is a concern.
This is an accident waiting to happen. No Way would I ever do that. One possible way to do it is to buy a motor from a DeWalt DWE7491 which has a longer arbor and replace this 7480 motor. Of course more research would have to be done to see if it would fit. Better yet, just buy a 7491 which I just bought used for $350.
This reminds me of the Jurassic Park thing: just because you could doesn’t mean you should. I have the same saw and like other people said you can use the 2 blade box cutting set on it no problem. This set up however looks like an open invitation for a visit from the grim reaper.
I have the same awesome saw and I can safely use a Freud 2-blade 1/4 & 3/8" reversible blade pair on this saw. I just run the board through twice to get a wider dado. Thanks for showing others about the feature that swayed me to get this used Dewalt over the newer ones.👍
There are incidents when using a dado stack on this model where the nut got loose during the cut. Don’t do this, definitely nothing more than like 1/4in in height with that many blades.
If you do this on this saw, then your peace of mind is an irrational delusion. Be sure to set aside some money to spend either on a new saw or to cover your health insurance copay.
@@wulf67I’m looking for a cross cut blade for the 8.25 Dewalt. Should I get a 7.25 blade or the DeWalt 40t 8.25? Just worried that other blades won’t fit properly.
@@he-mansuncle7661 I'd get the 8.25" because you'll be able to cut thicker boards with it. The problem with this video is that he's using a dado stack that barely allows for the arbor nut to catch one thread on the arbor shaft. In the case of your crosscut blade either the 7.25" or the 8.25" will be fine (as long as you don't try to put five of them on at the same time) 😂
I have an older model, the DW 745, which has a 10” blade. It will not support a dado stack either. As others have commented, what’s going on in this video is not a great idea. What I’ve done as a workaround to this limitation is to use a box joint cutter set instead. The one I have is from Freud, It has two blades that nest together. They can make either a 1/4” or 3/8” kerf, depending on how you orient the cutters. This particular setup can thread onto the arbor securely. Obviously it’s not a real dado cutter, you can’t make any adjustments to it. But it does cut 3/8” wide just fine, and it seems pretty safe.
I have a dado stack for my DW 744. I know I can't use the entire stack on it. I did buy a Dewalt dado throat plate a few years ago. From my manual it says: Do not attempt to stack thicker than 13/16" (20mm) and do not use dado blades larger than 8". When installing the dado stack do not include the inner clamp washer, replace it with the outer clamp washer. Then install the dado stack, arbor nut and tighten with supplied wrench. Years ago, I got a wobbly dado, but it's a pain to get that lined up sometimes.
Hi Red, nice try! Thx for this demonstration ! The DeWALT Saws have a great torque, and if it stays tight after more times on and off is the question! Even with 1 Blade if you don,t thight the Nut enough it comes loose! Happened to me the very first time, Blade stays on the arbor SPINNING FREE until it hits something like the Riving Knive mount or so! Took 2 teeth out of my Blade, and a bit of damage underside insert that was all !!! Didn,t fly out of the machine!! Better make the stack thinner so the nut will fully engage the Arbor! Btw, the 7492 has Dado Capability!!! Greetings Piet!!
Having only half the arbor nut engaged would scare the h3ll out of me. If there’s a failure related to the arbor, the blades or the arbor nut, the blades could easily leave the saw and who knows where they will wind up - possibly in the operator’s chest or forehead. There’s another video that shows both blades and one chipper, for a total 3/8” stack, and the arbor nut is flush with the end of the arbor. That seems a whole lot safer than having only half of the arbor nut engaged.
You must consider the blades center on the shoulderd portion of the shaft. Placing them on the threaded portion can allow for an improperly balanced part of the blad which can cause vibrations. This could damage the threads on the shaft as well as wear the bearing out in the saw. Though it can be done and I will be doing this myself I will only go as wide as the shoulder on the shaft permits.
I have the same saw and looking at doing 1/4 and 3/8 dadoes for drawer bottoms. Thinking either box cutter joint set or dado set without the chippers which I think may give me the 1/4 in width I’d need
On dewalt saws that do support datos the blades are on the threads so I don’t think you have much of an argument. From the 7480 to 7490 the supports a dato stack, it’s exactly the same part with a longer arbor. A am going to buy the longer arbor (and nut) and add it to my 7480
That's mad! A nut is only considered to be "in safety" when you have at least one whole thread to a a thread and a half protruding from the free side. You need maximum thread interlock to ensure it won't undo. You'll do yourself some serious harm.
Funny you said that, that’s the main reason I use that ‘old’ thing for, just for dado stacks. I’m temped to try the Dewalt like everyone else has but manual says not to and I’m listening to the manufacturer.
Using almost a full set of dado blades with little to no thread left is extremely dangerous on those small saws. My first portable saw is the older dewalt contractor table saw with the rocker on/off switch, then bought the same exact one you have. I still pop in 2 max 3 blades in and i make sure a leave full tread for nut. It's your life! For God sake. PS. I recently bought the 32.5 max rip contractor saw now I can use a full set of dado on it I am super happy. I used to built cabinets foryears, years ago with big delta table saws, now I only to remodeling.
It’s not just the lack of thread engagement in the nut that is the problem, it’s the washer! The washer is dished on purpose, to maintain a reasonable clamp load should the nut back off slightly. There’s a whole science in bolted joints. The washer isn’t a spacer, it’s a spring. The set up proposed here is extremely dangerous.
This is very dangerous; a better alternative would be a wobble (adjustable) dado although not as clean cut as the stacked, but you would still have a decent number of threads left for tightening the blade.
@@brianmurray667 I am a 35+ year experienced trim carpenter and cabinetmaker, i have that exact saw and have used it on many occasions on jobsites with a wobble dado, the width of the cut adjusts without much change in the width at the shaft of the dado and i always have enough thread to tighten properly you do however have to remove the outer washer and just use the tightening nut by itself, but i also do not go beyond about 1/2inch in adjustments and always use a zero-insert plate, works fine for occasional use .
@@selwyncallender399 I fail to see what 35+ years of experience has to do with safety, compatibility, and proper use. I have known experienced tradesmen that have made mistakes with safety and paid for it. Search RU-vid for Perkins Brothers and you will see an experienced contractor that lost multiple fingers in a jointer accident, for failing to follow safety standards and paying attention.
Doesn’t really look like a good idea. I have this saw and when it’s turned off, the blade stops almost instantly. With the dado blades, there was a lot of run on, which would be increasing wear on the motor. That’s without mentioning the potential for the blades flying off.
Watching this and thinking as soon as that blade started spinning, somewhere in the world an OSHA Manual just went up in flames. Thats a ballsy setup bro! My choice would be to sandwich three 7 1/4" blades together alternating the teeth from touching each other and have a full nut full of threads on the arbor.
As it happens, I have a 7485 AND a dado set on order, and only just realized that the 7485 supposedly can't take a dado set. But your video gives me hope! And if on the 7485 there is some kind of guard in the way, I'll consider modding. Over 50 yrs using power saws and never injured. (Except once slightly by a table saw guard. If you must use a table saw guard, be EXTRA careful!)
The comments on here are pretty negative, i think this is a awesome video, I have this same saw and want to do box joints with it, this should work fine! Yes I see you need to install with care but doable! Thanks for the great video!
If you really want to do that change the arbor out the arbors work on several different models there’s videos out there with people showing you that the arbors on the dado work on other models. It’s about 100 bucks total but to save yourself from getting killed it’s worth it the 745 does have a smaller motor and will after awhile wear it out.
I'm scared to go this route but do use an Oshlun 8" Finger/Box Joint 2-blade set. Depending on how you orient them, you get a 1/4" or 3/8" cut/groove/dado (check throatplate clearance on the 3/8" setup. You may have to create a custom throat plate or file off an edge of the factory plate when using it this way. I did). The caveat is that the second blade is resting on some of the arbor threads (but not enough to keep the nut from fully engaging). At first, this was not a problem. Over time though, it has caused a few of the threads nearest the solid portion of the arbor to become flat. Now I get a very small (1/128"?) height differential on half of the cut. I.e., the blades still cut flat but half the cut is offset. I will assume the second blade is "wobbling" somewhat on the threads that have flattened. If it is wobbling, it's so slight that the human eye cannot detect it. This is not a major problem but does require, in some instances, sanding or chisel work if you want your mating piece to be completely flush with your cut. Over time, using multiple blades to form a dado may cause the same problem if they are resting on some of the threads. Also, I will at times, use just one of the blades to create a small (5mm?) groove to accept box bottoms on my pieces or to cut a small rabbet/rebate when needed. Each blade has 30 teeth so I feel safe using it this way but keep my cuts nowhere deeper than 1/4" at a time or even less with harder woods. Be safe!
Wow thank you I have the same saw and was always wondering about this as I know some of the later models did say they excepted dado blades. Then I was thinking maybe I should sale mine and upgrade. They also make an Insert from DEWALT. Worked good enough for me Thanks for the video
There is a video online where a guy replaces the arbor on this saw (assuming 7480) with the longer one from the 7491rs. He includes part numbers for the arbor and the bearings, etc. Not a difficult task. I did it on mine and it works great.
Well done. I admire your fortitude. We may Never know the real reason Dewalt purposely built their most popular contractor saws to not accept a Dado stack, but I would be willing to be it was determined by a room full of actuaries who likely concluded that they could save a bunch of money by putting in a smaller motor that would wear out sooner if they didn’t also alter it so adding a stack was discouraged along with the instructions discouraging it. So for what likely saves them ten bucks We gen an inferior product that they also likely concluded means a portion of the customer base would buy a second one or upgrade sooner as well. Garnering them even more profit overall. Bastards.
More likely they designed this "portable jobsite saw" to meet the needs of tradesmen doing rough carpentry and trim and casework installation ON JOBSITES, and they designed it to be able to handle those common jobsite tasks (like ripping a cabinet filler, stair riser, or a piece of oak flooring, not doing joinery on an ebony piano case) while also keeping it light enough to be PORTABLE so that one skinny 20 year-old or arthritic old man can get it in and out of his truck by himself with a cigarette in his mouth or carry it up and down stairs or even the occasional makeshift ladder slapped together with bowed and twisted 2x4 culls and extra purlins. They probably correctly assumed that if a person needed a full-size cabinet saw they would buy one of those instead of buying this product and complaining that the reason their stock Hyundai Sonata doesn't generate as much torque as Kyle Busch's dyno-tuned, bored and cammed-out Camaro ZL1 is because of corporate greed. There's a reason that a decent cabinet saw costs 5 times more than a jobsite saw, and there's a reason that woodworking craftsmen pay that price to have a real belt-driven cabinet saw in their shop that is actually DESIGNED for what they do instead of just picking up a 40 pound direct drive jobber saw on sale at Home Depot and calling it good.
Don’t worry about the naysayers. Just concentrate on the mission, and proving the man wrong. Tools were made to be pushed to the limit…. If you think this is unsafe don’t use it.
Dewalt flat says NO cannot do Dato cuts with this table saw. I knew it could be done. I would find away to make the drive bolt longer is all perfect job.
Just because you can doesn't mean you should. Dado sets are much heavier than regular blades and bench top saws are not designed for them. The bearings will not last, the universal motor is no where near as powerful or robust as the induction motor on a real table saw. Bad idea all around.
I have a dewalt 7485. Going all the way to 5/8 seems scary but if I were to just do 1/4 dado would anyone recommend that? I’m assuming I would have more thread for the bolt.
I was really surprised how much cutting power (and torque) this saw had out of the box. I've used other (10" saws) previously and was pretty surprised with the speed and cutting ability of this Dewalt saw.I have bolted mine to a table to minimize movement which I highly recommend.This is a Great saw ru-vid.comUgkxPeGkHOMe05FySypTOvYumxMn-xi39oRe with a light to see your cutting line (not a laser line).I'd recommend this saw fro anyone looking to upgrade from a 10" miter saw.
I have the Porter Cable job site saw. It will safely take up to a half inch dado stack. I know the older DeWalt job site saws would take a full dado stack.
Confucius say "just because you CAN do something, not mean that you SHOULD!" A plugged-in toaster CAN fit quite easily into a bathtub full of water. You CAN fit like 18 of them in there. The electrician manual says to not plug more than about six of them on any one circuit at the same time though, but I do what I want! I don't follow anyone's rules. I don't even call it a dado stack. It's a Freedom Stack!
Pretty cool, glad it didn’t fly off the arbor when you fired it up. I have the 745(?) with the same arbor length and wanted to try this Kinda sounded like it bogged down when you ran the 2x4 as a rip cut but you did take a big bite Light passes and it seems doable for sure with pine I’m guessing not doable with white oak unless extremely light passes
Obviously, you were successful and unharmed, but I'd never accept less than a full nut/thread engagement..if/when those blades become disengaged from arbor due to centrifugal or excessive vibration forces, what they impact is totally unpredictable..maybe I'm being overly cautious..please reconsider before proceeding
I’ve done similar but decided the most I’m comfortable with are two blades for 1/4”. I’ll make a few extra passes for 3/4” when I need it but I appreciate the flat tooth and the smooth dado I don’t have to clean up. It’s my second amendment right to use a dado blade! At least my 4 year old kid won’t decapitate his younger brother’s dead with a dado stack. ;-)
Manufacturers instructions says don't use a dado stack.... but because a big corporation who have made a world wide reputation on building tools can't possibly have done the science on this you've gone for it anyway (y) makes sense (y)
honestly after reading the many wise comments on why this should not be done, if I were you I would take the video down just to avoid having someone do what you did and get hurt pretty badly or even get killed.
I'm confused. If the T.S. specicfically says in the owners manual not to modify or use a dado because of high risk of bodily harm, ...............help me understand, because this is confusing to a point.
Lots of good comments below explaining possible reasons for Dewalts statement. So far I’ve had no issues but I only use the dado set for very small projects. If you push the saw too hard with a dado set there is increased risk.
"Standard 3/16" blade"?!? Standard ìs typically 1/8" in cabinet shops, and typically weekend warriors are using thin kerf blades in their portable tablesaws, which are thinner than 1/8". (PS: 3/16" is thicker than 1/8", in case I had to tell people that.)
I don't need to be an engineer with a working lifetime experience to know one needs what I call a "full nut" so basically you should see/feel the spindle end once tightened. I suspect in this video, removing one chipper blade would give enough spindle to work safely. As for the motor not being powerful enough; rubbish. My DW745 had an 1800 watt motor running off 240v. Plenty of power for DADOing softwood to 1/2". I very recently sold that saw without ever using or owning a dado set but my new saw a DW7491 does accept a dado stack. A 8.5" Freud DADO set arrived today. I'm sorta glad I never watched this video when I had the DW745, I just see images of blood spurting out of my neck or part of my face hanging off. No thanks.
Super sketchy. I have the745 and am thinking of giving it a go. I suppose as long as you check that nut for snug every time and stay out of the blades line of site it should be ok.
If you consider the arbor’s length and if you have a throat plate in place (and why wouldn’t you?) the danger is not to the user, it is to the dust shroud of the saw, the underside of the table, and the expensive set of blades you bought.
rule o dee thumb is two threads, BUT i wouldn’t trust this. i guess it might be alright in a pinch, but you should wear a suit of armor and a helmet. no joke
This guy is a big time "wannabe" authority" - To begin with: There is NOT two threads on the arbor exposed (barely one thread - the first thread he is counting is a starting thread). Secondly: He says the nut is what he describes as "half way on". LOGIC DICTATES: If there are two threads exposed on the arbor after the baldes are installed then the nut only can go on with two threads. There are approximately (at most, six to seven threads inside the nut so the nut is NOT "half way" - barely one third of the way on. This is a VERY DANGEROUS venture. I give NO advocation to his presentation.
This is the most dangerous power tool in your workshop and you are doing this. Read the instructions that came with the saw. You should not be encouraging owners of this saw (like me) to follow your poor example.🇦🇺🇦🇺🇦🇺🇦🇺
