How the heck do I cut straight!?

[toylocost]

I have built probably more than 10 boxes, all car audio. They either get rattle canned or covered in carpet. The straightness of my cuts has always bothered me but never been a problem, until now.

Now I am cutting up wood that is alot more expensive AND in the end all the edges will be seen. They need to be perfect. How are you guys doing this!? I have a table saw with a fence but everytime I clamp the fence down it moves and my cuts end up crooked. Every time I want to cut I spend too long measuring the fence position and still end up with crooked cuts, even when I think I've measured well enough to make up for the fence. There really is no good way to measure fence position against the blade that I've found

The last few boxes that I've built, the only thing I use is the hand held skill saw. The only other thing I can think of to do is use my skill saw then sand the edges down to straight.

IS THERE A BETTER WAY? or do I just need to get a more expensive table saw and fence?

Here is my saw...

[PressureFM]

Have you tried removing the fence and make a manual fence with a straight piece and some clamps?

[simon7000]

First be sure the table is level.

To check the fence, take a 24" wide board 36" long. Set the fence to 2" use extra clamps to hold it, and keep cutting the board until there is 4" left. If it is 4" at one end and something else at the other end then the fence is not parallel to the blade. Take the error divide it by the number of cuts and adjust the fence by 2/3 of that amount. Then do it again.

If the cuts are curved it means the set on the blade is wrong. That may also cause the fence to move. Get a new one and not a cheapie!

Finally cut the edges slightly over and trim with a router or belt sander.

BTY there should be a nut at the back of the fence that adjusts clamping pressure!

[sreten]

Hi,

Impossible to tell just by looking at, but modify it such that the clamp does not
move. One option might be to spray the clamp rails with a textured paint or
car body undersealer, or similar. Or work out how to improve clamping, a
guide that moves simply isn't a guide, perhaps just roughen the rails and
/or the clamps, perhaps rubber sheet glued to the clamps, etc.....

rgds, sreten.

[infinia]

it's your fence and rail clamping, mess around or upgrade to Biesemeyer fence system
Comparison between Unifence and Biesemeyer Rip Fences

[tade]

Well, your table saw appears rigid, so my advice is out the window...

(a joke really!)

I'm reading the given advice!

[Cal Weldon]

Are you left handed? I see your fence is set on the left side of the blade.

[pinkmouse]

The other thing to check is your blade, make sure it's sharp. If you have to force the material through, then you're likely to push everything out of alignment. You shouldn't need any more pressure than you can exert with your little finger, (well, for sheet materials, ripping a 6x4" length of old oak may need a little more. ).

[revboden]

when using a saw like that I draw my lines on the board then cut the piece a little over. next i'll use a oscillating edge/belt sander to get that last little bit of wood off. for box sides that are exposed i'll cut the board a little large install it and use a flushing bit in a router if i'm in a hurry. The sander works better if I have the time. http://www.ridgid.com/Tools/EB4424-Sander/

[evanc]

Even the humble table saw needs some set up

good blades. I like either
Forrest Saw Blades - Woodworker 2 Saw Blades Information
or
Forrest Duraline HI-A/T Saw Blade Information
Seems to me the 1/8" thick blades are the way to go.

The fence and blade must be parallel. With the blade all the way up I use my ruler flat on the table and check the same tooth in front and back. Adjust as necessary.

If the saw won't do it then there is the router and straight edge. A pia, but good cuts. Look for router bits that sheer cut.