Cutting on TS - what am I doing wrong?

[Brian Dormer]

I have a good (Craftsman 22114) TS. Blade is a Freud. Everything (rip fence, miter fence, blade) is aligned to machine shop precision (< .001 in). The saw cuts like a dream. But the operator is another question...

Recently, I had to cut 3 3/4" melamine panels 18" x 27" - The 18" cuts were no problem - I set the rip fence and cut all 3 panels. For the 27" cut, I had a little problem - the stock 22114 rip fence only goes out to 25" (I want to shift the rails over to increase the rip capacity - but that's a different project) - so I decided to mark the pieces with a flat-back tape measure - mark a "little vee" like I was taught in shop class and line up the center of the vee with the edge of the blade (blade goes to the waste side) and cut. So far - so good.

But when I set the 3 18" x 27" panels together - I found that in the 18" dimension they were perfect (as expected, since they were all cut on the same saw with no changes to the fence). In the 27" dimension - there was about 1/8" variation from the "longest" to the "shortest" board. Huh? :eek: How'd that happen?

My fix was to set up the miter fence with a stop block at 26 3/4" (27" was somewhat arbitrary and that was about as far as I could stretch it - good thing I didn't need 27 1/2") and trim the pieces. Then everything was perfect. :)

My question is - WHY didn't just marking and cutting the pieces accuratly work? :confused: Obviously, I'm missing something. I'm reasonably sure I didn't flub marking or aligning the marks to the blade (I did all 3 boards one after the other) - but I still ended up with boards that were close but didn't quite match.

bd

[Dennis Putnam]

I can't say what you did wrong but have you considered making a rip sled (aka panel cuting jig) for yourself? Once you get it squared up, ripping panels that are messed up are a thing of the past. At least it certainly solved the problem for this amateur TS operator.

[Bruce Page]

Brain, it sounds to me like your 27” edge is not square to the 18” edge. Unless your panel is perfectly square to begin with it is very difficult or impossible to square a panel using only the fence. You should first cut the 18” dimension using the fence (as you did) but then you need to make a cross-cut using the miter gauge or a sled.

[Cliff Rohrabacher]

Unless your panel is perfectly square to begin with it is very difficult or impossible to square a panel using only the fence.

Indeed, and in my experience the factory edges are neither square nor straight.

Add to that the plain fact that when you use a tape and a mark you have introduced no less than 4 potential errors into the mix.
1.) the tape & it's placement will transfer any out-of-square or parallegram error you picked up by referencing off the a material's factory edge.
2.) the eyeballing of the mark placement will never be perfect.
3.) the mark is made by hand and won't be perfect.
4.) the eyeballing of the cut to the mark.

That's a lot of potential error

[glenn bradley]

On my FlatBack I have to be careful (one of your identified error points) that the hook is sitting flat over the edge. It has a tendence to creep up, hanging onto the edge of the board by just the tip of the hook. This is a weakness of the flatback tape; no structure (curved tape) to keep this from happening (I love my FlatBack however).

A sled and a stop block would prevent this. If you don't have a sled, I would build one. I have found them very valuable as my 22124 only reaches 30" so, same challenge just a few inches farther away.

[Ted Miller]

Brian, I know this sounds crazy but I have way to many tape measures in my shop and when I start a project with one particular tape I keep that the whole project.

Also make a few sleds, I have three of them at different lengths and widths and they cut great...

[Jim Becker]

I agree with Ted...a sled for cutting the panels to length is a good idea.

[Lee Schierer]

I don't fully understand how you made the cuts after you marked the pieces. How did you hold them in alignment while you did the cutting? Did you put the waste against the fence? If so, the stock craftsman fence doesn't clamp down square 9 out of 10 times you move and clamp it. I tossed my stock fence a few years ago and put on a beismeyer 37" and have not regretted it since. I do regret I didn't do it sooner. It is well worth the investment. http://home.earthlink.net/~us71na/lsfence2.jpg

[Dell Littlefield]

Did you mark all three cuts then cut? If so, you didn't allow for the kerf. I've done that.

[Brian Dormer]

All very good ideas - but I don't believe I made any of those errors. With the exception that the hook on the end of the flat-back tape might have crept up the panel (that flat-back tape is a new addition to the shop). I used that tape (and ONLY that tape) for the whole project. But something as simple as not watching the hook end must have been the cause. I'm going to try measuring a couple panels with that tape using the same procedure and comparing results. But I'm about 90% sure that the hook slipping is it.

I checked the panels for square before I started and the cut panels are square. I've flipped the panels over and end for end and checked - all 4 edges still line up - if there was any squaring error it would show using that procedure.

I did cut with the waste against the fence the first time (so I had to adjust the fence for each cut), when things came out wrong - but used a sled for the cuts that came out right. I think it's time to slide those rip fence rails over and get more rip width.

A Biesmeyer would be "nice" - but I spent the bankroll getting the TS - a new fence is going to be a ways off, unless approved by the Finance Committee (ie wife). Besides - the stock fence works really well - I know the Biesmeyer purists don't like it much - but I haven't had any problems with it - and it came out of the box very close to perfectly aligned.

bd