Replies

1. 
   JMartinsky | Aug 25, 2006 05:24am | #1

   Forgive me as I am not familiar with that particular saw, but it sounds to me like sawdust built up on the threads of the lowering mechanism, or on the "stop". Just a guess.

   best,

   John

1. 
   oatman | Aug 25, 2006 05:39am | #2

   John: Thanks for your reply. I got in there and blew out all the dust and checked the stops. They appear to be OK. I haven't measured the blade and just read in an archived message that there are variations in blade diameters. Maybe that's it.

    

   Dennis

1. 
   JasonWhite | Aug 28, 2006 04:41am | #23

   I read somewhere to put a 7-1/4" circular saw blade in and raise it as much as possible.  Then, put in your 10" blade and finish it. 

   TFToolfanatic (a.k.a. The man formerly known as "Toolfreak")

2. 
   polarsea1 | Aug 25, 2006 05:45am | #3

   That's normal for my saw, your's too looks like. My solution is to route a 1/4" groove on the bottom of the insert.

1. 
   oatman | Aug 25, 2006 05:52am | #4

   Good idea. I was able to make several zero clearance inserts when the saw was new and had no problems lowering the blade far enough. Weird.

3. 
   forestgirl | Aug 25, 2006 06:14am | #5

   "The saw blade no longer lowers far enough to clear the blank's underside...."  Oatman, it probably never did!  Most contractor saw blades stop their downward movement before they get under the level of the table.

   PS (sorry, I was laughing so hard at my 80# dog sitting in hubby's lap, I punched Post too soon).  You can also put a smaller diameter blade on the saw to start the kerf with.

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 
   

   
   

   ---

   Edited 8/24/2006 11:17 pm by forestgirl

1. 
   oatman | Aug 25, 2006 07:05am | #6

   Forestgirl: Although long of tooth, I distinctly recall, shortly after purchasing this saw, making several ZC inserts using the "lower the  saw blade, insert blank and raise the spinning blade up through the blank" method to create customized inserts for several  10 inch blades. I still have these inserts (a little worse for wear) so I must assume I have not completely hallucinated this problem. I just can't arrive at a reasonable explanation. Thanks for your input.

1. 
   Knotscott | Aug 25, 2006 03:38pm | #7

   I'm at a loss for an explanation....my first thought was the same as Forestgirl's, b/c I've never had a saw that had enough clearance for a full thickness insert with a 10" blade unless it was precut underneath.  Was it possible that you used an 8" or 9" blade back when? ...Or a 10" blade that had been sharpened enough to reduce the diameter a bit?

   A possible answer that would leave your sanity intact is that the trunnion gears and ways have loaded up with sawdust. 

    

4. 
   highfigh | Aug 25, 2006 03:54pm | #8

   If you look at a lot of the commercially available ZC inserts, they have a dado going through the area where the blade will rise through it. Place a board over the insert and clamp it in place before raising the blade through it while making the slot. A poster here raised it with his hand over the insert with bad results (fortunately, it could have been a lot worse).

   "I cut this piece four times and it's still too short."
5. 
   hammer1 | Aug 25, 2006 05:17pm | #9

   That's normal for many saws. To cut the slot for a new insert, you place a smaller diameter blade on the saw. Just remember not to bevel the blade with a wood throat plate in place. For bevel cuts, I use the metal insert.

   Beat it to fit / Paint it to match

1. 
   oatman | Aug 25, 2006 05:44pm | #10

   Thanks, all, for your input. I'll use my 8" dado to precut the underside of the blanks. 

1. 
   MRGreer | Aug 25, 2006 07:58pm | #11

   I too have a Delta contractors saw, it's about 8 years old, before they changed the leg design and moved production out of the US.  Anyway, I have made zero clearance inserts for this saw and I could swear I had the same problem with the 10" blade.  I looked at the inserts last night and couldn't see where I had modified the bottom, so I must have figured a way to make the plung cut, I just don't remember how I did it.  The other insert was for my dado set and it's 8" so not a problem.

2. 
   mufti | Aug 25, 2006 08:52pm | #12

              To avoid changing blades (the kerf may be different) you could do as I and clamp your stock on the top of the table and raise your regular blade in a number of positions, then use the best old ZC insert to trace out the new ones. It's quicker than cutting and raising. 

1. 
   dtraversi | Aug 25, 2006 10:08pm | #13

   Okay- I'll admit it-
   I made my first ZCI and "plunged" the insert onto a spinning blade. I only did it because I thought "surely delta would not make this simple little design flaw- I must be missing something"I only did it one time- I don't reccomend it to anyone. It just made me wonder if that's what other people did and just forgot.I respect my saw much more now than I did when I first purchased.Make a bunch and change to the smaller blade :-)
   Dave

1. 
   Rich14 | Aug 26, 2006 12:33am | #14

   Dave,

   "I made my first ZCI and "plunged" the insert onto a spinning blade. "

   I just cannot believe that!

   My gosh, that is the most frightening thing I can imagine. I am sitting here with sweat running down my back as I read what you did. I honestly had to stop reading and catch my breath.

   Thank God you lived to tell about it.

   For whatever reason, cutting inserts scares the bejesus out of me. Fortunately it is an infrequent task. I clamp a 4x4 over the insert, raise the blade sloooowly, as I "hide" below the saw table and still cringe with each rotation of the wheel! I simply hate it.

   Rich

2. 
   cadiddlehopper | Aug 26, 2006 03:36am | #15

   Well, I can see that I will have to make some more ZCIs for my Delta saw. I use 1/2-inch plywood. I may have lowered the insert onto the spinning blade. The blade was below the top, but not by 1/2 inch. It didn't scare anything out of me at the time.BTW, for height adjustment I install #4x3/8 flat head wood screws on the underside to match Delta's locations. Works fine.Cadiddlehopper

3. 
   dgreen | Aug 26, 2006 04:14am | #16

   Don't forget to put a pin or lip on the far end so that if something goes south the insert won't fly east.
   Since the house is on fire let us warm ourselves. ~Italian Proverb

4. 
   JMartinsky | Aug 28, 2006 12:00am | #18

   I may have to turn over the "Evil Knevil" moniker..............

6. 
   DougU | Aug 27, 2006 08:37pm | #17

   I think there was someone(on here) that did a ZC by droping it down on the blade and the thing took a left turn and they ended up getting cut pretty bad. I dont recall the details, just remember the reason.

   You can try to search it but that never works worth a damn so........

   My table saw depending on the brand of blade will do the same thing, I know that my Forrest blades are a little bit larger in diameter and I have a problem making the ZC inserts. I usually take my right angle grinder and hog off a little of the back side until it sits down in the slot, then I clamp the insert down before starting the blade.

   Doug

7. 
   wdrite | Aug 28, 2006 12:33am | #19

   To make zero clearance inserts for my table saw, I set the fence even with the right edge of the insert, raise the blade to about an inch or so, tilt the insert at about a 45 degree angle with the end nearest you in the insert slot and against the fence.  Being very careful and aware of where the blade will exit, lower the insert onto the blade  and down into the table slot.  Be careful that the end does not come up out of the slot.  Once the insert is flush with the table, you can hold it down and raise the blade until the slot is the desired length.

1. 
   dgreen | Aug 28, 2006 12:43am | #20

   Sounds like a recipe for disaster to me. It would be much safer to do as previous posters have suggested and groove the bottom of the insert first then clamp it in place and raise the blade through it.

   Since the house is on fire let us warm ourselves. ~Italian Proverb

   Edited 8/27/2006 5:46 pm by dgreen

1. 
   wdrite | Aug 28, 2006 12:52am | #21

   You are right of course that the grooving method is safer.  You could also use thinner material.  I have had no problem with my method over the last 40 years and by the way, I'm not crazy enough to stand directly behind it.

1. 
   dgreen | Aug 28, 2006 01:05am | #22

   Glad you have not been hurt, gives me the hebee jebees just thinking about it.
   Since the house is on fire let us warm ourselves. ~Italian Proverb

8. 
   9619 | Aug 28, 2006 05:47am | #24

   Oatman,
   I checked my Delta Contractors Saw. I cleaned the sawdust out. Still the blade only goes down slightly below table level, just like others have said.

   I read about an interesting way of making the equivalent of a zero clearance insert. You put a thin piece of plywood, say 1/4" or of 1/8" masonite under his fence. I tried this with my Biesemeyer and it works. The fence can be moved and locked with the plywood under it. You can use that same piece of plywood many times with the blade at different angles just by moving the piece of plywood. The piece obviously must go most of the way across the table, and support the width of wood that you are using.

   I haven't tried cutting any wood like this, but I did read about it, and I tried locking the fence over it. I know this isn't what you were asking about, but it might solve your problem another, and cheaper way.

   Does anyone out there have any experience with this technique?

   Mel

   Measure your output in smiles per board foot. 

1. 
   DonMitchell | Aug 29, 2006 05:42am | #25

   No offense meant to anyone but after reading that, I gotta say that anyone that turns the saw on and then tries to lower the insert down onto the blade is not exactly the sharpest chisel in the toolbox!  

   I've seen kickbacks come off a saw table fly across the shop and end up stuck half way through a wall.  Not exactly something I want to try and stop with my body!! 

   To each his own I guess!

   Don

1. 
   9619 | Aug 29, 2006 02:21pm | #26

   Don,
   I read your reply. Either my message was not clear, or you were responding to one of the other posters who lowered the zero clearance insert onto the blade. I wrote about using a rectangular piece of thin masonite or plywood. You put it on the saw table, but under the fence. Of course, the blade must be all the way down to do this. Then you raise the blade through the masonite. Since the masonite is held down by the locked fence, it cant kick back.
   But then again, I think you meant to answer someone else. In any case, I share your concerrn about kickback.
   MelMeasure your output in smiles per board foot. 

1. 
   DonMitchell | Aug 30, 2006 03:18am | #27

   Mel,  I got no problem with what you suggested.  I was directing my comments to the few that suggested lowering the insert down onto the spinning blade.  Just thinking about where that is headed makes me cringe!  Don

   Measure, cut, cuss