2 Cuts to a "Perfect" Miter Sled

a few years ago I made a video called five cuts to a perfect cross cut slit where I show you the five cut method and also giving you my formula for calculating mirror and making the adjustments since then I had many requests for me making a video on the miter sled now I hesitated on that for a couple of reasons first I was new to YouTube so when I posted that video there were a lot of positive comments and very supportive but there was a few that was pretty negative and downright nasty they were saying like you're you've been making it way too complicated we're not sending it to the moon it's not rocket science you know I have one person saying that woodworking is supposed to be fun and your video just totally ruined it for me I even have one person say once you take your map and just shove it up your you-know-what and so I said Wow welcome to YouTube so early on I learned that haters will always hate so a couple years later after my video came out I start to notice that there are other people on YouTube using my formula to make their own slide videos so I thought well it can't be that complicated they're using it and they're accepting it and also had a couple of emails from we're working magazines from other countries asking me for permission to see if they can write an article based on my video that they would give me credit and also reference it back to my video of course I was thud Ernest is you know of course and thanks for asking because he shows integrity and I just also want to thank all the people on YouTube that actually used it and reference it back to me I really appreciate that so today I'm going to show you how I make my mighty sled so that you can cut perfect 45s on either side without using a whole lot of math okay now I promise you I will keep it as simple as possible I won my sled to be able to cut all my 45s on one side I would put it together and it should fit I don't want to have to cut one on the left and then one on the right just so that I can cancel out any discrepancies to get my 90 sometimes it's just a hassle to have to keep track of which side I cut especially when you start doing a little bit more complicated joints like these now can you imagine trying to keep track of all this that would be insane sometimes you don't have a choice like this piece here sometimes I have to cut one on the right and they flip it over and cut this on the left keep track of all this and which side I cut now I'm gonna make a couple of mighty slits one of them is gonna be an attachment for your existing slit and then I'm gonna make one that's totally separate there's advantage and disadvantages now you know that a triangle has three sides with three angles totaling 180 degrees in my previous five cuts that video I say that if you have a sled that's dialed in you can cut a perfect 90 this angle is taken care of and all we have to do is calculate for our two 45s I'm gonna do that using your basic trig function now I promise no complicated math so I'm not gonna get into the sine and cosine and all the other stuff because all we need to know is that if we have a ninety degree here and the length of a is equal to the length of B then these two angles will be equal and so in our case will be 45 degrees so to make a miter attachment for your existing crosscut sled I'm gonna start off with a piece of plywood I'm gonna make my first cut so I can get a nice clean edge and then I'm gonna flip it around put it against my fence and then make my second cut this will give me my perfect 90 now by now you probably realize that I'm gonna need a sled to make this Jay so if you haven't made one yet you might want to go to my other video it's called five cuts to a perfect crosscut sled there I will give you a detail in sure-tan how to build one I will show you the calculation for error and also make the proper adjustment so the more accurate your sled is the better your jig is going to turn out so if you're between two and three thousandths of an inch off per cut I would say don't worry about it that's good enough if you can get it better than that then there's gonna be better for you now that we got our 90 the next thing I want to do is I want to make sure that this distance which I'll call a is equal to distance which I call B so I'm gonna take my sled off put this up against my fence make this cut put this eye up against my fence and make this cut then this way I know that a or equal to B so I just finished my cut now I know where some of you might be thinking I'm gonna make a cut from point to point get my triangle I'm gonna put this up against my fence and then there's my miners that well I'm not gonna do that first of all it's very difficult to make a perfect cut from point to point secondly it's kind of a waste of material and also adds weight to my sled besides I can make three minor fences out of this piece here's I'm going to do this I'm gonna set my fence to two inches I'm gonna cut them on this side stop shy I'm gonna cut on this side and stop shy and then finish it with a bandsaw then I'll repeat myself and get two more fences out of this so here's my ninety degree I'm going to cut this one and then I'm gonna cut this one I mark it out so it'll be a good inch away from here so we stop shy of that here's my name I'll put this against the fence so here's my first one I'm gonna get two more out of this [Music] so here are my three pieces the next thing I want to do now is to cut A+ relief on the bottom here I change over to my flat top blade so as you can see it's much easier to get my two points of contact by saving the fence and cutting my v-shape the length on the outside is the same as the length on the inside and by cutting both of these sides without changing the fence setting they are both identical to make the cut from corner to corner perfectly is not easy now to test it out I'm gonna put my angle up against my fence if your sled is then on 90 I can cut on each side to get a perfect 45 if your slab is slightly off from 90 like this I'll show you how to calculate and make the proper adjustment so here's my to cut method first you get a piece of scrap wood either four or five inches in width your first cut is on your sled to get your 90 from here you take it to your miter sled and cut off the corner now try to cut close to the tip don't cut over this will be your a sigh and this will be your B side just like your miter fence this is the a and this is the B once you've cut it we can measure it and if a equals B you've got a perfect meier on either side because we split your 90-degree fence perfectly in half so let's test it out this will be a and this will be B this is a and this is B alright let's measure this now the key is you have to make sure that you hold your caliper right here instead of trying to go like this because it's not easy to keep this steady so I'm gonna hold it right here put this piece up against my fence on this side and I'm just gonna move it until it stops okay right about there okay so you reach three eight zero six or six are now almost seven so now I'm gonna do it this side but I'm gonna flip it over I'm gonna put this up and put this up against my fence hold it tight and oh my gosh he's exactly 0.06 and a half so I'm I'm pretty much nuts on there okay so I got lucky with this one I made this late not too long ago and I was able to dial it in to within half a thousandth of an inch after my fifth cut which makes it a little easier for me to do perfect matters now I'm gonna show you how to calculate and make the adjustment just in case the cut didn't come out perfect I'm gonna do that by making a totally separate dedicated miter sled where my fence does not have a chance to be squared off with my blade so my runners are in place now remember the runners has to be perfect not too tight and not too loose I've shown how to cut it perfectly in my fight cut sled video so I'm not going to go through it here I'm gonna place my base right in the center of my soccer I'm cutting miners here so I don't need to offset my sled I'm just going to align it flush to the table back here or you can put your table saw fence up here and just align it to that it doesn't matter so my friends will be flush against the back here I'm not worried that if this is to the blade just make sure that your fence is long enough so that it would hit these two points but not too long where it gets in a way when you put your workpiece here so let me just quickly put this all together so you're probably wondering why my mighty save is so big why I have two slits in my shop I have a big one like this for cutting big stock ladies and then also make a really small one using my last fence for cutting small joints like these I make it nice and small so it'd be a very light so let's calibrate this so the first thing is I want to screw off my test pieces so I can keep my 90 okay so here we go here's my 90 I'm gonna put it out here okay here we go Hey so this is my a this is my B so this is my a this is my B so let's take a measure and see what we get let's measure a first and it looks like right there three point eight three nine this is three point eight three nine let's see what B measures - well like this but I'm gonna flip it around B and let's see it would be okay and I say point eight two eight eight point eight two eight so we eleven thousand seven inch smaller on the BSI so let me give you the formula so the formula is a minus B divided by two for the two angles divided by the width of your test piece in my case is four inches and then you multiply that by the length of your miter fence in my case is 16 inches is a eight point eight three nine minus B which is eight point eight two eight divided by two and then divided by four times that by sixteen and my error is 22 so I'm twenty two thousand seven inch too short on the BSI so I found 20 mm of an inch on my fila gate I'm gonna put it on the side that's short which is my B sigh so I'm just going to put it right here ladies up against there make sure this is centered now I want to make sure that this is my square angle I'm not sure about this side so the square side has to be out this way I can't cut it like this because like I said I don't know if this is square so here we go okay let's see what we got here's my a and here's my B let's measure that Hey let's measure that Hey okay it's a three point eight two four you see what the B says point eight to four and 8.8 to three and a half almost for some nuts on so if you're happy with the calibration from here I just put a couple of dabs of glue on the bottom let us sit and let attack up and then screw it down I would probably prefer having my school coming from the bottom up so there you have it very simple so I think I kept the video and the process pretty simple and that I've shown you how to make a - that you can cut perfect 45s on either side I hope the video was helpful please share with someone and don't forget to tell them where you learned it from thank you for watching please subscribe and I'll see you in the next video you

Channel: William Ng

Views: 269,873

Rating: 4.9539299 out of 5

Keywords: woodworking, how-to, building, tools, school, learning, miter sled for table saw, miter sled, miter sled jig, miter sled calculation, miter sled diy, miter sled video, how to make a miter sled, table saw miter sled

Id: AgVthkUE4AU

Length: 19min 34sec (1174 seconds)

Published: Thu Feb 15 2018