table saw alignment

[pejman]

Hi

I am wondering anyone has the same issued that I have with my RIGID R4512 table saw I can not get the blade aligned any time I raised the blade I have  around 20 thou different between front and back of blade I went through manual again and again but sound likes it doesn't work. any advice will be appreciated.

 

Thanks

[james wilhelm]

HI , there is a very good discussion going on that deals with your saw , Jay Boutwell added some very good reply,s  on how to set up this saw , it is very good  and worth reading and he know,s what he is talking about , think this will help solve your problem , JIM !!

[Jay Boutwell]

Hi pejman, 

There is a defect in trunnion of some of  your model of saw and the raising of the blade allows the trunnion to move out of alignment.  Some have replaced the trunnion  which is a major operation.   Some are fixed by using shims and depends on how serious of a defect that there is.   Shimming the trunnion will require several trials but in most cases can be done.  In either case the saw must then be totally re-aligned.  I have recently posted some details on doing this and it does not only pertain to the ridged saw but most saws that I have either owned and or repaired for other wood workers in my area.  It seems to be the trunnion that causes the most problems with saws that do not cut correctly.  It it is not a blade problem then it is usually the trunnion and in fact is the very first thing to check out and correct before you can do any alignments of any other part of the saw.  Some make the mistake of setting up the saw based on the lower position of the arbor.  (the trunnion carries the arbor and does the raising and lowering of the blade and arbor.)  What is forgotten is that that the arbor and blade is carried upward and downward in a path depending on the angle of the what he trunnion is directed.  If it is set at a direction other that a true 90 degrees and the alignment is done at the lower end of its travel then as the arbor and trunnion is raised the further off the alignment will be.  The same goes for a trunion that is loose and or bent. 

With this in mind check the trunnion mounting both at the hinging point and at the opposite end as the end opposite the hinged end will be trapped in a track or some type of guide to keep the trunnion in alignment and ridged .  Check this for looseness and sign of movement from the lowest point up to the highest point.  Check to be certain that the trunnion is not cocked in the cabinet as well.  It should be mounted so that both ends are in alignment with each other In respect to table top throat and miter tracks meaning it should not be mounted so that the hinged end is closer to the left side of the saw cabinet that the sliding end.   Some of the trunnion problems come from the end that is against the guide is tilted and due to the guide assembly being mounted crooked and can be corrected by shims to align the guide to a position that it controls the lift to a straight

90 degrees as it travels up and down in the trunnion's travel.

 The shimming of table saws to make them as near as perfect in not uncommon.  When I bought my current table saw which is a delta it was new right off the show room floor.  I brought it home and before I even began to cut very much wood I did some alignment checking on it and found that even though it is an expensive saw the cuts were less the to be desired.  Having a back ground in a machine shop I tore the saw totally apart and very carefully began rebuilding the saw.  I removed the arbor and  found some extra clearance in the bearing races housings.  I line bored them and found some replacement bearing that had the same inter bore that would fit the arbor shaft but a larger outer housing of which I took care of when I re-bored them during the line boring.  I replaced the single cast iron pulley with a double pulley system and replaced it with a lathe turned steel pulleys.    This made a positive drive with no slippage of the belt under the changing of loads from, a light pull to a sudden heavy pull as what happens in a production type of environment.   I took most of the bounce out of the saw.  I recall shimming and re-shimming as well as grinding some of the mounting areas of the saw to make them fit correctly and to align with the mating parts in a correct manner.  There was several hours of time spent doing this but the results are phenomenal.  It cuts like there is nothing going through the saw and the results are smooth.  I do en lay work off the table saw and glue up straight off the saw with out needing a jointer.  I seldom have burned wood and all cuts are square and are at the miter angle that I want them to be.  It cuts thin wood up to 2 inch think wood in one pass and does this it the hardest of woods.  One of my favorite woods to build with is hickory and everyone can imagine how hard and grain inter twined this wood is.  It cuts hard and soft wood without any issue.  

As far as how smooth running is it?  With the saw running I can balance a nickel on edge on the saw table edge with out if dancing and or moving.  I am writing this to encourage you as most any saw regardless of make or model can be made to run like a million dollar saw.  It just takes patience and lots of understanding on how it works.  In reality all the saw does is spin the blade in the controlled path and angle you ask it to.  It is just that some saws need more understanding and some work to make them do what you want them to. 

 

With as much variation in degrees difference I would suspect that either the rear of the trunnion is loose and is moving and or the guide system is at fault.  

I hope that this will give you some ideas as to the problem.