[BWSmith]

No negativity here.....but you might not like what I'm gonna say?

We ROUTINELY work wood to .0015....and infact a lot of shops do.Heck,take a look at any decent shaper or moulding machine,widebelt sander,etc.etc.

But the discussion here is about TS sleds.....correct me if that's wrong.It seems you've taken an idea or design from your readings and research and you're "running" with it......correct me if thats wrong.

Where you got derailed,so to speak,was in your assumption on "that" process or "best practice".

Even in a machine shop,"cutting" only gets you so far(metrology).....at some point in the quest for high accuracy work you'll be utilizing other processes.It's not a dang bit different in high accuracy wood machining.

So,not disparaging your need/want for accuracy.....but can present a rather compelling arguement why/how a "sled",irrespective of its build quality......can only,go so far.You need to understand,there are other processes that are infanately faster/cheaper/better if you're chasing .oooo's.

If you insist on using sleds....read,and understand how "backlash" effects/affects the process.And interetingly,is the "flip-side" arguement to machine vs hand work in the quest for accuracy.

Best of luck,BW

 

[BWSmith]

Just for the record....I think you're wasting time trying for any kind of *real accuracy on a table saw,as there's too much stacked tolerances.And this is to include Martin's,Altendorf's etc.....*real accuracy:even getting into the .001's

But TS's in general seem to be the "darling" pce of equipment of the woodworker crowd....so any advice or direction that dosen't place them at the head of the pecking order,usually goes unheeded.Just sayin TS's within the industry are most often held for accuracy jobs pretty far down the list of importance.

Next is the chicken and the egg....horse and cart.If you don't have anyway of measuring,how and why would you be on a journey chasing .oooo's?You want a square pce of panel...lets say 2'x2'.My point is,how are you going to measure the 2'(24")?You gonna use a tape measure?


Dig around in below link.They're used by a lot of folks in the accuracy biz.May answer some instrument questions.

http://www.longislandindicator.com/p4.html

 

[BWSmith]

First off,drops ain't called "drops" for nuthin,lame attempt at humor.But seriously,don't think I've ever(40+ years)measured a drop to see what effect it had on the part?


I figured you were pulling a diagonal on largish panels.Or making spot measures to see if both ends were the same.....I now see thats not what you're intending,apologies.