Delta 36-725 Table Saw Blade Alignment Procedure
The Delta 36-725 table saw is a great tool designed and priced for the amateur woodworker and suitable for a professional shop where a less powerful motor is acceptable. I call saws like this Cadillac's for Harry Homeowner. The two most often asked questions about the Delta 36-725 table saw are the best blades to use and how to properly align the blade. Understand that I am certainly not a woodworking expert nor an authority on table saws or blades. I am a retired engineer and have been an amateur woodworker for many years. I wrote a review and a follow-up review of this saw and I have answered all questions to the best of my ability. These are my thoughts and my methods written so as to focus on the first time owners of table saws and those less experienced.
For reference, here are the links to the original and follow up reviews
Review
http://lumberjocks.com/reviews/3822
Follow-up review
http://lumberjocks.com/reviews/3881
Blades Selection
There seems to be a wide variety of opinions about the best saw blades. My approach is quite simple. I don't get into the debates. I am retired so I have outlived blades like my Forrests. I simply can't afford the price tag and the expense of sharpening. I'm in the less than $50 blade market now. I use them up and throw them away. I was using the Diablo blades for a long time but changed to the Irwin Marples series on the recommendation of Knotscott. The Diablo series is a fine blade but I feel I get finer cuts with little or no sanding and less chips thrown in my face with the Irwin Marples. Note that this is the Irwin Marples series and not simply the Irwin brand. I gave up on all Irwin blades years ago until Knotscott's review of the Marples urged me to give it a try. I use a 50T combo for general work and a 22T for ripping. I have an 80T on my miter saw. I confess that I do not always change to the ripping blade as often as I should but I get fine cuts with the 50T on 3/4 or thinner softwood stock. I'm retired. I get to be lazy when I want.
In my opinion Knotscott is the Guru, the Grand Poobah of saw blades and table saws. I know that writing in such a way that dummies like me can understand it is difficult and time consuming. Thanks for all you do Scott. His ABC's of Table Saws and Tips for Picking Saw Blades weigh heavily in my decisions and I encourage all to read them both. Here are the links.
ABC's Of Table Saws
http://www.woodworkingchat.com/blogs/tips-for-picking-table-saw-blades/8790-the-abc-s-of-table-saws
Tips for Picking Saw Blades
http://www.woodworkingchat.com/blogs/tips-for-picking-table-saw-blades/4919-tips-for-picking-saw-blades
The riving knife on the Delta 36-725 states that it is 0.087" (2.2 mm) and requires a 10" (254 mm) blade. It also says the blade must have a 0.100 (2.6 mm) kerf and a 0.073 (1.85 mm) body thickness. What the Devil does all that mean? Well, if you read Knotscott's writing on saw blades you'll understand it. But, even then the reality is you may still not have ALL that information when you go blade shopping. For example, some blades (like my Marples) only say it's a 254 mm blade. I have seen some with all the details but the ones I have only say 254 mm. What can I say? The blades work fine. I have friends using other blades with no other information and they work fine. Today's fad is thin kerf blades. Delta made a decision to have a middle of the road riving knife. It's slightly more than a really thin blade but works fine with standard and (what do I call it) slightly thin or just a bit skinny blades. If you want a Twiggy blade (look her up youngsters) then you can buy a thin kerf riving knife. If you're a newbie, I recommend you just run what you brung. Build your woodworking skills and don't worry about fads. You'll know when you think you've outgrown a standard blade. Hell, I'm still happy with the old style. But then again I'm old and shy away from new stuff especially thin blades that make me worry about things like blade flex.
Blade selection is a personal choice based on your skills, the type/thickness of the stock you're cutting and your financial capabilities. I can only recommend that you buy the best of what you can afford to own and maintain. I also suggest that you know the area you live in. Are there reasonably priced people that can sharpen your expensive saw blades? I'll add to that by asking if they can sharpen them correctly? The last of my Forrest blades went in the trash after the chainsaw sharpener in my area was done with them. Any new saw blade, including the one that came with the saw, will do the job. Get the best you can and keep them sharp and clean. If you're financially unable to buy finer expensive blades then buy cheaper. Keep them clean and they'll give good service for longer than you would expect.
Checking Blade Alignment
There are a lot of fancy gadgets on the market to measure blade alignment. These range from complete jigs/fixtures to dial gauges. I used a dial gauge to align the blade on this saw ONLY because I wrote the reviews and people wanted to talk thousandths of an inch. Frankly, I don't normally get into such things. I only need to know if the blade is close enough or out too much. If it's in it's in. If it's out I adjust and don't care what the measurement used to be. I want it less and I don't care how much less. I'm going to adjust and the "too much" measurement is going away. Table saws were around hundreds of years before dial gauges were. Now, I'm not bashing any tools or anyone. Do it the way you want - the way you feel confident and comfortable. But for those who don't own such fixtures or dial gauges - don't get your knickers in a twist. You can bring your blade into alignment without them. You can use a ruler, an adjustable square or even a stick. In is in and out is out. I'm going to describe my simple, old-fashioned way. There should be no problem for those with fixtures or dial gauges to interpret the methods accordingly.
Begin by raising the blade all the way up. Make sure the blade is perpendicular/square to the cast iron table.
Now you can use the miter gauge with a small ruler or piece of wood. Just make sure the miter gauge is square to the blade. Another way (my preference) is to use a combination square riding against the inside (blade side) of one of the slots in the cast iron table. Which slot is not important. The right slot is closer, but by convention the left slot is typically used. I think it is easier to hold something steady with my left hand and rotate the blade with my right so I use the left slot. Maybe a lefty will think otherwise.
Use a felt marker to mark a tooth on the forward edge of the blade. Which tooth does not matter but I have my preference. Teeth alternate left, right, and flat. I look for a flat tooth because it is easier for me to slip a feeler gauge (dollar bill) in without hanging on a sharp point. More on that later.
Move the ruler or stick on the miter gauge until it just touches the marked tooth. Don't push. It's a feel thing. Just touch the tooth. Hold the ruler/stick firmly and don't let it move. If you are using an adjustable square in a miter slot, then extend the ruler blade to just touch the tooth. Lock the blade in the square head. Double check that it did not move when you locked it down and still just touches the blade.
Rotate the blade so the same tooth is at the back of the saw. Slide the miter gauge/adjustable square to the back of the blade. Note that you may have to rotate the blade slightly to get past any angled teeth now in the front of the blade. Check that the same tooth touches the ruler/stick. If it does then your blade is in alignment.
The following assumes you are measuring from the left of the blade. If there is a gap then the blade is towed in. The fence is typically used to the right of the blade. Used here, towed in means the blade is not square and the back is angled towards the fence. If the marked tooth wants to push the ruler/stick away then the blade is not aligned and it is towed out (away from the fence). If this happens then rotate the tooth back to the front and measure the gap there.
It is important to understand what happens when a blade is not aligned. We'll talk about how much is too much in a moment. Simply put, the front of the blade will begin a cut and start a kerf but the angled back of the blade will nibble away at one side or the other of the kerf (slot cut in the wood). Within reason this is not a dangerous situation. The nibbling will cause some extra saw marks that may increase the need for sanding. This can become dangerous if the angle of the blade is too much - especially if it is towed in towards the fence. This can cause the wood to bind and the trailing teeth can bite the wood and throw it back at you. I call this a George Washington - where you get wood-in-teeth. A few things figure into whether the trailing teeth (rotating upwards) will bite into the wood. The tooth count, angle of the teeth, the feed rate, etc. The focus is that there is a point where an improperly aligned blade can be dangerous. Slightly out of alignment is typically not a dangerous situation. Yes, there are factors that can kick the wood back at you that have nothing to do with blade alignment. A twist in the grain or feeding the stock too fast are a couple of examples. But a poorly aligned blade is a built in hazard that can and should be corrected.
Now, how much is too much? Delta does not recommend performing a blade alignment unless the blade is more than 10-thousandths out. I can't argue with the safety factor here. I don't personally operate my saw if it is out that much. Maybe not for safety but for a finer finished cut. Remember, I'm retired and get to be lazy. I don't like sanding any more than I have to and the nibbling rear teeth will leave more saw marks. I use a dollar bill as a feeler gauge. I was taught that years ago and it has always worked well for me. For the "I speak in thousandths" fans out there, a dollar bill is about 4-thousandths of an inch thick. If the dollar bill passes through the gap between the ruler/stick then I align the blade. If it does not pass then the blade is less than 4-thousandths out and I leave it alone. You can use feeler gauges to measure the exact width of the gap if you wish. Tow in - measure the gap at the rear. Tow out - measure at the front. You can also make note of the measurement on the ruler touching the tooth and extend it through the gap to touch the tooth. The difference is the width of the gap.
When I wrote the reviews of this saw I felt a certain ownership of the questions asked. That meant that I did more to this saw, including trying different methods than I normally would. This includes using a dial gauge and developing my own blade alignment method. My saw's blade alignment is dead on zero. I've intentionally knocked it out several times and realigned it using different methods. I am confident that the blade can be brought to zero. It's just a question of "does it have to be zero?" My personal opinion is NO it does not have to be zero. Mine is zero only because of my testing and proving my alignment method to myself. Otherwise anything less than 4-thousandths would have been good enough for me - without knowing the actual measurement. I also do not think that more than 4-thousandths is too much. The dollar bill gage is simply what I was taught by my grandfather who built cabinets for new homes - back when they didn't come from a big box store. I don't perceive a safety issue with Delta's recommendation to not align the blade if it is less than 10-thousandths out. I just don't like sanding so I keep mine at 4-thousandths or less.
Blade Alignment Comments
This process is the method I use to align the blade on the Delta 36-725 table saw. It is simple and straightforward if the methods are followed. I cannot emphasize enough that you must know the difference between just cracking screws/bolts loose and loosening them 2, 3 or more turns. Loosening the screws too much can result in the motor assembly unexpectedly dropping. This can cause damage to the saw and/or injury to you. Have patience. Follow the steps. Do no more than is necessary for your purposes. Enjoy your saw and work safely.
Of course I have to add my disclaimer. I'm an amateur. This is the way I do it. You accept all responsibility and risk if you follow this procedure.
For those of you old school types out there, the trunnions can be used to adjust the blade alignment if the blade is out only a couple of thousandths of an inch but this method is simpler. 6-thousandths or less seems to be the norm for this saw. Most woodworkers would not bother to adjust the blade with this variance. However, manufacturing variances do occur and you can experience more blade deviation that does mandate adjustment.
Delta has published a set of Power Point slides that show how to adjust the blade alignment using only the rearmost motor riser tube clamps.
The Power Point slides can be found at: https://dl.dropboxusercontent.com/u/29106827/Delta%20Contractors%20Saw%2036-725%20Blade%20Alignment.pptx
For those who have trouble viewing the slides, a free Power Point viewer is available from Microsoft at: http://www.microsoft.com/en-us/download/details.aspx?id=6
There are some points that need to be addressed about the Delta slides/procedure. Firstly, Delta is not recommending that any alignment be done unless the blade is out more than 10-thousandths of an inch. That is 1/100 of an inch. For the measuring tape impaired, that is less than 1/64 of an inch (16-thousandths). 1/64 of an inch is one half the little tick mark on the tape (1/32). Sorry for the fun I'm having but so many have asked me for help cuz the blade is out "1/16 of an inch". Then they get their calculator and tell me that's 63-thousandths. When we get into how he measured the guy tells me that it is ½ of the little tick mark and insists that 1/16 is one half of 1/32. We were all newbies once and we do all understand. But that does not mean we can't have a laugh.
Personally, I feel that 10-thousandths is not dangerous and exceeds the capabilities of most newbies anyway. Yes, it leaves a minor bit more saw marks but does not pose a serious kickback hazard. My point is not to raise a debate over the minimum allowable blade alignment. My only point is to advise Newbies to think about if they really feel they have to adjust the blade. Don't obsess over what others insist on. You will do over time and you will learn over time. Concentrate on building your personal skills and don't get wrapped up in debates. Most experienced saw owners would find 10-thousandths to exceed what they are willing to live with. Again, not a debate - just a thought for newbies.
Back to Delta. Why would Delta recommend such a thing? I cannot be sure, of course, but my experiences make me feel that they are simply protecting themselves. Even frivolous lawsuits cost big bucks. I have helped many people put their saws back together because they read a short blog somewhere on the Internet and charged ahead. Oops! They dropped the motor because they didn't know what the screws were and loosened them too much. Yes my writings can be wordy but I try to take the time to explain. After all, I'm not writing for those who already know. In all but one dropped motor case, each one of them blamed the stupid saw. Yep, the saw is stupid. It does not give one thought about what you do. People like this have made Delta, and people like me, leery about how much help to give - hence my disclaimer about not being responsible for anything at all. Look in the mirror for someone to blame if you drop the motor.
The next thing to note about the Delta procedure is that it is only half - the back half - of the alignment capabilities of this saw. You can get your saw well within 10-thousandths of an inch using the Delta method. But why only the back half? Because the safety set screw is on the front riser tube. This is where you can drop the motor if you are not careful. Delta is simply protecting themselves (my opinion). I can't say that I blame them in today's world. They can't give an amateur class disclaimer.
Blade Alignment Procedure
Make sure the power switch is in the off position and unplug the saw.
Lower the saw motor at least halfway down. This makes it easier to see and work in the tight spaces.
Remove the back panel of the saw.
You may loosen the wing nut on the dust chute and lower it if you wish. I personally don't find it to be in the way.
Note that raising and lowering the motor will not affect your adjustments unless you really loosen the screws and have everything free swinging. Again, this is dangerous. Just crack them loose. They will be snug enough to raise and lower the motor without issue.
Look at the rear motor riser tube. That's the silver tube the motor rides up and down on. Follow the tube up towards the table and see the two hex screws that lock the tube in the clamping collar. Using the 3/16-inch hex wrench that came with the saw (the one you used for the rails, etc.) crack both screws loose.
Now raise the motor up and bump or twist it in the direction you want it to go in order to zero it in. It may be easier for you to bump/twist the motor if it is lowered about half way. Do so if it works for you. Then raise it up to check the alignment.
Note that you should take care not to pull down on the motor when you twist. Don't add extra weight or extra forces in directions you don't want to go. Focus on just twisting/bumping horizontally.
Let's face it, you don't have a calibrated bump/twist tool at the end of your arm. It's a bit of trial and error to get the blade dialed in, especially the first time you do it. Have patience and keep tweaking until the blade alignment is satisfactory to you. Bump, check, bump, check. You'll get it. Or, you'll get what the saw is capable of with the procedure so far.
Lower the motor and retighten the clamping screws by snugging from one to the other until they are both tight. Do not tighten one completely and then the other. This can throw your alignment off a bit.
Up to this point, there are no differences from the Delta procedure. Most saws can be dialed in using only the rear riser tube clamp. I encourage you to try this first, as there is no danger of dropping the motor. This is all the adjustment you need unless your blade is really out of alignment. If you just can't get the blade aligned and need more adjustment then continue on. Remember my amateur status disclaimer. You are responsible and no one else if you continue on.
Look again at the rear riser tube and follow it up to the locking collar. Notice that there is a screw hole in the middle of the collar but no screw in it. If you look at the Delta Power Point slides you may note that this screw hole is not visible. It is always hidden (intentionally or unintentionally) by the motor position or text boxes.
Now look at the front riser tube and follow it up to the locking collar. Everything is the same as the rear EXCEPT that there is a screw in the hole centered in the collar. This is a safety set screw. It seats in a groove in the front riser tube and keeps the motor from dropping. Call this the danger screw. The groove in the tube is shallow. You WILL drop the motor if you loosen this screw too much or loosen the collar clamping screws too much.
Lower the motor about halfway down. Crack the rear then the front riser tube clamp screws loose. Now crack the safety set screw loose. Remember that this screw holds the motor. Just crack it loose.
Now bump/twist the motor in the direction you want it to go. Raise the motor and check the alignment. Check, bump, check until the blade is aligned.
You can throw your alignment off by tightening one screw completely at a time. Retighten the collar clamping screws by snugging from one to the other, front to back, until all four are tight. It's cramped in there. Make sure you don't knock your motor/blade out of alignment with your arm. Now retighten the safety set screw.
Now stop holding your breath. Sometimes you get lucky and the blade lines right up. Sometimes you spend the better part of an hour. As many times as I've done this I can give the motor a twist and a love tap and bring it right in. I've read so many short statements (with no explanations or cautions) from people who claim to align the blade in 5 minutes. Bull. They must have gotten very lucky on one bump and only be talking about the alignment. They must be leaving out the back panel, going from back to front to raise/lower the blade, etc. Figure on an hour and be happy when it is less.
Sit back and have a beer. Everything is harder the first time. Think about how easy it will be if you have to do it again. Or better, if your buddy buys a saw and you just zip through it and get to show off.
The Delta 36-725 table saw is a great tool designed and priced for the amateur woodworker and suitable for a professional shop where a less powerful motor is acceptable. I call saws like this Cadillac's for Harry Homeowner. The two most often asked questions about the Delta 36-725 table saw are the best blades to use and how to properly align the blade. Understand that I am certainly not a woodworking expert nor an authority on table saws or blades. I am a retired engineer and have been an amateur woodworker for many years. I wrote a review and a follow-up review of this saw and I have answered all questions to the best of my ability. These are my thoughts and my methods written so as to focus on the first time owners of table saws and those less experienced.
For reference, here are the links to the original and follow up reviews
Review
http://lumberjocks.com/reviews/3822
Follow-up review
http://lumberjocks.com/reviews/3881
Blades Selection
There seems to be a wide variety of opinions about the best saw blades. My approach is quite simple. I don't get into the debates. I am retired so I have outlived blades like my Forrests. I simply can't afford the price tag and the expense of sharpening. I'm in the less than $50 blade market now. I use them up and throw them away. I was using the Diablo blades for a long time but changed to the Irwin Marples series on the recommendation of Knotscott. The Diablo series is a fine blade but I feel I get finer cuts with little or no sanding and less chips thrown in my face with the Irwin Marples. Note that this is the Irwin Marples series and not simply the Irwin brand. I gave up on all Irwin blades years ago until Knotscott's review of the Marples urged me to give it a try. I use a 50T combo for general work and a 22T for ripping. I have an 80T on my miter saw. I confess that I do not always change to the ripping blade as often as I should but I get fine cuts with the 50T on 3/4 or thinner softwood stock. I'm retired. I get to be lazy when I want.
In my opinion Knotscott is the Guru, the Grand Poobah of saw blades and table saws. I know that writing in such a way that dummies like me can understand it is difficult and time consuming. Thanks for all you do Scott. His ABC's of Table Saws and Tips for Picking Saw Blades weigh heavily in my decisions and I encourage all to read them both. Here are the links.
ABC's Of Table Saws
http://www.woodworkingchat.com/blogs/tips-for-picking-table-saw-blades/8790-the-abc-s-of-table-saws
Tips for Picking Saw Blades
http://www.woodworkingchat.com/blogs/tips-for-picking-table-saw-blades/4919-tips-for-picking-saw-blades
The riving knife on the Delta 36-725 states that it is 0.087" (2.2 mm) and requires a 10" (254 mm) blade. It also says the blade must have a 0.100 (2.6 mm) kerf and a 0.073 (1.85 mm) body thickness. What the Devil does all that mean? Well, if you read Knotscott's writing on saw blades you'll understand it. But, even then the reality is you may still not have ALL that information when you go blade shopping. For example, some blades (like my Marples) only say it's a 254 mm blade. I have seen some with all the details but the ones I have only say 254 mm. What can I say? The blades work fine. I have friends using other blades with no other information and they work fine. Today's fad is thin kerf blades. Delta made a decision to have a middle of the road riving knife. It's slightly more than a really thin blade but works fine with standard and (what do I call it) slightly thin or just a bit skinny blades. If you want a Twiggy blade (look her up youngsters) then you can buy a thin kerf riving knife. If you're a newbie, I recommend you just run what you brung. Build your woodworking skills and don't worry about fads. You'll know when you think you've outgrown a standard blade. Hell, I'm still happy with the old style. But then again I'm old and shy away from new stuff especially thin blades that make me worry about things like blade flex.
Blade selection is a personal choice based on your skills, the type/thickness of the stock you're cutting and your financial capabilities. I can only recommend that you buy the best of what you can afford to own and maintain. I also suggest that you know the area you live in. Are there reasonably priced people that can sharpen your expensive saw blades? I'll add to that by asking if they can sharpen them correctly? The last of my Forrest blades went in the trash after the chainsaw sharpener in my area was done with them. Any new saw blade, including the one that came with the saw, will do the job. Get the best you can and keep them sharp and clean. If you're financially unable to buy finer expensive blades then buy cheaper. Keep them clean and they'll give good service for longer than you would expect.
Checking Blade Alignment
There are a lot of fancy gadgets on the market to measure blade alignment. These range from complete jigs/fixtures to dial gauges. I used a dial gauge to align the blade on this saw ONLY because I wrote the reviews and people wanted to talk thousandths of an inch. Frankly, I don't normally get into such things. I only need to know if the blade is close enough or out too much. If it's in it's in. If it's out I adjust and don't care what the measurement used to be. I want it less and I don't care how much less. I'm going to adjust and the "too much" measurement is going away. Table saws were around hundreds of years before dial gauges were. Now, I'm not bashing any tools or anyone. Do it the way you want - the way you feel confident and comfortable. But for those who don't own such fixtures or dial gauges - don't get your knickers in a twist. You can bring your blade into alignment without them. You can use a ruler, an adjustable square or even a stick. In is in and out is out. I'm going to describe my simple, old-fashioned way. There should be no problem for those with fixtures or dial gauges to interpret the methods accordingly.
Begin by raising the blade all the way up. Make sure the blade is perpendicular/square to the cast iron table.
Now you can use the miter gauge with a small ruler or piece of wood. Just make sure the miter gauge is square to the blade. Another way (my preference) is to use a combination square riding against the inside (blade side) of one of the slots in the cast iron table. Which slot is not important. The right slot is closer, but by convention the left slot is typically used. I think it is easier to hold something steady with my left hand and rotate the blade with my right so I use the left slot. Maybe a lefty will think otherwise.
Use a felt marker to mark a tooth on the forward edge of the blade. Which tooth does not matter but I have my preference. Teeth alternate left, right, and flat. I look for a flat tooth because it is easier for me to slip a feeler gauge (dollar bill) in without hanging on a sharp point. More on that later.
Move the ruler or stick on the miter gauge until it just touches the marked tooth. Don't push. It's a feel thing. Just touch the tooth. Hold the ruler/stick firmly and don't let it move. If you are using an adjustable square in a miter slot, then extend the ruler blade to just touch the tooth. Lock the blade in the square head. Double check that it did not move when you locked it down and still just touches the blade.
Rotate the blade so the same tooth is at the back of the saw. Slide the miter gauge/adjustable square to the back of the blade. Note that you may have to rotate the blade slightly to get past any angled teeth now in the front of the blade. Check that the same tooth touches the ruler/stick. If it does then your blade is in alignment.
The following assumes you are measuring from the left of the blade. If there is a gap then the blade is towed in. The fence is typically used to the right of the blade. Used here, towed in means the blade is not square and the back is angled towards the fence. If the marked tooth wants to push the ruler/stick away then the blade is not aligned and it is towed out (away from the fence). If this happens then rotate the tooth back to the front and measure the gap there.
It is important to understand what happens when a blade is not aligned. We'll talk about how much is too much in a moment. Simply put, the front of the blade will begin a cut and start a kerf but the angled back of the blade will nibble away at one side or the other of the kerf (slot cut in the wood). Within reason this is not a dangerous situation. The nibbling will cause some extra saw marks that may increase the need for sanding. This can become dangerous if the angle of the blade is too much - especially if it is towed in towards the fence. This can cause the wood to bind and the trailing teeth can bite the wood and throw it back at you. I call this a George Washington - where you get wood-in-teeth. A few things figure into whether the trailing teeth (rotating upwards) will bite into the wood. The tooth count, angle of the teeth, the feed rate, etc. The focus is that there is a point where an improperly aligned blade can be dangerous. Slightly out of alignment is typically not a dangerous situation. Yes, there are factors that can kick the wood back at you that have nothing to do with blade alignment. A twist in the grain or feeding the stock too fast are a couple of examples. But a poorly aligned blade is a built in hazard that can and should be corrected.
Now, how much is too much? Delta does not recommend performing a blade alignment unless the blade is more than 10-thousandths out. I can't argue with the safety factor here. I don't personally operate my saw if it is out that much. Maybe not for safety but for a finer finished cut. Remember, I'm retired and get to be lazy. I don't like sanding any more than I have to and the nibbling rear teeth will leave more saw marks. I use a dollar bill as a feeler gauge. I was taught that years ago and it has always worked well for me. For the "I speak in thousandths" fans out there, a dollar bill is about 4-thousandths of an inch thick. If the dollar bill passes through the gap between the ruler/stick then I align the blade. If it does not pass then the blade is less than 4-thousandths out and I leave it alone. You can use feeler gauges to measure the exact width of the gap if you wish. Tow in - measure the gap at the rear. Tow out - measure at the front. You can also make note of the measurement on the ruler touching the tooth and extend it through the gap to touch the tooth. The difference is the width of the gap.
When I wrote the reviews of this saw I felt a certain ownership of the questions asked. That meant that I did more to this saw, including trying different methods than I normally would. This includes using a dial gauge and developing my own blade alignment method. My saw's blade alignment is dead on zero. I've intentionally knocked it out several times and realigned it using different methods. I am confident that the blade can be brought to zero. It's just a question of "does it have to be zero?" My personal opinion is NO it does not have to be zero. Mine is zero only because of my testing and proving my alignment method to myself. Otherwise anything less than 4-thousandths would have been good enough for me - without knowing the actual measurement. I also do not think that more than 4-thousandths is too much. The dollar bill gage is simply what I was taught by my grandfather who built cabinets for new homes - back when they didn't come from a big box store. I don't perceive a safety issue with Delta's recommendation to not align the blade if it is less than 10-thousandths out. I just don't like sanding so I keep mine at 4-thousandths or less.
Blade Alignment Comments
This process is the method I use to align the blade on the Delta 36-725 table saw. It is simple and straightforward if the methods are followed. I cannot emphasize enough that you must know the difference between just cracking screws/bolts loose and loosening them 2, 3 or more turns. Loosening the screws too much can result in the motor assembly unexpectedly dropping. This can cause damage to the saw and/or injury to you. Have patience. Follow the steps. Do no more than is necessary for your purposes. Enjoy your saw and work safely.
Of course I have to add my disclaimer. I'm an amateur. This is the way I do it. You accept all responsibility and risk if you follow this procedure.
For those of you old school types out there, the trunnions can be used to adjust the blade alignment if the blade is out only a couple of thousandths of an inch but this method is simpler. 6-thousandths or less seems to be the norm for this saw. Most woodworkers would not bother to adjust the blade with this variance. However, manufacturing variances do occur and you can experience more blade deviation that does mandate adjustment.
Delta has published a set of Power Point slides that show how to adjust the blade alignment using only the rearmost motor riser tube clamps.
The Power Point slides can be found at: https://dl.dropboxusercontent.com/u/29106827/Delta%20Contractors%20Saw%2036-725%20Blade%20Alignment.pptx
For those who have trouble viewing the slides, a free Power Point viewer is available from Microsoft at: http://www.microsoft.com/en-us/download/details.aspx?id=6
There are some points that need to be addressed about the Delta slides/procedure. Firstly, Delta is not recommending that any alignment be done unless the blade is out more than 10-thousandths of an inch. That is 1/100 of an inch. For the measuring tape impaired, that is less than 1/64 of an inch (16-thousandths). 1/64 of an inch is one half the little tick mark on the tape (1/32). Sorry for the fun I'm having but so many have asked me for help cuz the blade is out "1/16 of an inch". Then they get their calculator and tell me that's 63-thousandths. When we get into how he measured the guy tells me that it is ½ of the little tick mark and insists that 1/16 is one half of 1/32. We were all newbies once and we do all understand. But that does not mean we can't have a laugh.
Personally, I feel that 10-thousandths is not dangerous and exceeds the capabilities of most newbies anyway. Yes, it leaves a minor bit more saw marks but does not pose a serious kickback hazard. My point is not to raise a debate over the minimum allowable blade alignment. My only point is to advise Newbies to think about if they really feel they have to adjust the blade. Don't obsess over what others insist on. You will do over time and you will learn over time. Concentrate on building your personal skills and don't get wrapped up in debates. Most experienced saw owners would find 10-thousandths to exceed what they are willing to live with. Again, not a debate - just a thought for newbies.
Back to Delta. Why would Delta recommend such a thing? I cannot be sure, of course, but my experiences make me feel that they are simply protecting themselves. Even frivolous lawsuits cost big bucks. I have helped many people put their saws back together because they read a short blog somewhere on the Internet and charged ahead. Oops! They dropped the motor because they didn't know what the screws were and loosened them too much. Yes my writings can be wordy but I try to take the time to explain. After all, I'm not writing for those who already know. In all but one dropped motor case, each one of them blamed the stupid saw. Yep, the saw is stupid. It does not give one thought about what you do. People like this have made Delta, and people like me, leery about how much help to give - hence my disclaimer about not being responsible for anything at all. Look in the mirror for someone to blame if you drop the motor.
The next thing to note about the Delta procedure is that it is only half - the back half - of the alignment capabilities of this saw. You can get your saw well within 10-thousandths of an inch using the Delta method. But why only the back half? Because the safety set screw is on the front riser tube. This is where you can drop the motor if you are not careful. Delta is simply protecting themselves (my opinion). I can't say that I blame them in today's world. They can't give an amateur class disclaimer.
Blade Alignment Procedure
Make sure the power switch is in the off position and unplug the saw.
Lower the saw motor at least halfway down. This makes it easier to see and work in the tight spaces.
Remove the back panel of the saw.
You may loosen the wing nut on the dust chute and lower it if you wish. I personally don't find it to be in the way.
Note that raising and lowering the motor will not affect your adjustments unless you really loosen the screws and have everything free swinging. Again, this is dangerous. Just crack them loose. They will be snug enough to raise and lower the motor without issue.
Look at the rear motor riser tube. That's the silver tube the motor rides up and down on. Follow the tube up towards the table and see the two hex screws that lock the tube in the clamping collar. Using the 3/16-inch hex wrench that came with the saw (the one you used for the rails, etc.) crack both screws loose.
Now raise the motor up and bump or twist it in the direction you want it to go in order to zero it in. It may be easier for you to bump/twist the motor if it is lowered about half way. Do so if it works for you. Then raise it up to check the alignment.
Note that you should take care not to pull down on the motor when you twist. Don't add extra weight or extra forces in directions you don't want to go. Focus on just twisting/bumping horizontally.
Let's face it, you don't have a calibrated bump/twist tool at the end of your arm. It's a bit of trial and error to get the blade dialed in, especially the first time you do it. Have patience and keep tweaking until the blade alignment is satisfactory to you. Bump, check, bump, check. You'll get it. Or, you'll get what the saw is capable of with the procedure so far.
Lower the motor and retighten the clamping screws by snugging from one to the other until they are both tight. Do not tighten one completely and then the other. This can throw your alignment off a bit.
Up to this point, there are no differences from the Delta procedure. Most saws can be dialed in using only the rear riser tube clamp. I encourage you to try this first, as there is no danger of dropping the motor. This is all the adjustment you need unless your blade is really out of alignment. If you just can't get the blade aligned and need more adjustment then continue on. Remember my amateur status disclaimer. You are responsible and no one else if you continue on.
Look again at the rear riser tube and follow it up to the locking collar. Notice that there is a screw hole in the middle of the collar but no screw in it. If you look at the Delta Power Point slides you may note that this screw hole is not visible. It is always hidden (intentionally or unintentionally) by the motor position or text boxes.
Now look at the front riser tube and follow it up to the locking collar. Everything is the same as the rear EXCEPT that there is a screw in the hole centered in the collar. This is a safety set screw. It seats in a groove in the front riser tube and keeps the motor from dropping. Call this the danger screw. The groove in the tube is shallow. You WILL drop the motor if you loosen this screw too much or loosen the collar clamping screws too much.
Lower the motor about halfway down. Crack the rear then the front riser tube clamp screws loose. Now crack the safety set screw loose. Remember that this screw holds the motor. Just crack it loose.
Now bump/twist the motor in the direction you want it to go. Raise the motor and check the alignment. Check, bump, check until the blade is aligned.
You can throw your alignment off by tightening one screw completely at a time. Retighten the collar clamping screws by snugging from one to the other, front to back, until all four are tight. It's cramped in there. Make sure you don't knock your motor/blade out of alignment with your arm. Now retighten the safety set screw.
Now stop holding your breath. Sometimes you get lucky and the blade lines right up. Sometimes you spend the better part of an hour. As many times as I've done this I can give the motor a twist and a love tap and bring it right in. I've read so many short statements (with no explanations or cautions) from people who claim to align the blade in 5 minutes. Bull. They must have gotten very lucky on one bump and only be talking about the alignment. They must be leaving out the back panel, going from back to front to raise/lower the blade, etc. Figure on an hour and be happy when it is less.
Sit back and have a beer. Everything is harder the first time. Think about how easy it will be if you have to do it again. Or better, if your buddy buys a saw and you just zip through it and get to show off.
. Having built how shops, sold the tools when I had to more, and done that at least twice, this is the last one. 
