Trimming wood that's too long

[s_busby_uk]

So I'm building a frame for my cabinet and I was about 3mm off on some of my timber cuts - is the best way to get this down to a precise measurement to sand it or is there another way?

I'm still a n00b...

[Drnick]

If you have a chop saw or a table saw that would be the way to go.  I'm assuming you don't in which case a careful cut with a hand saw and then sand it out.  If you have a belt sander and a strong person that can get behind it you can use that but if you do that you may want to think safety first the belt sander can and will tear a piece of lumber out of your hands quicker then you can blink.  No point asking how I know that, Its fairly obvious.   

[shponglefan]

For precise trimming, I use a router and a flush trim bit.

[s_busby_uk]

Hmm, yeah I'm thinking I may need to actually just buy a router. They seem to be quite useful.

[markc74]

If you're trimming down the grain then a router can work well. If you're trimming across it then you'll need to block the timber in with some spare wood and clamps otherwise you'll probably end up splintering the end. More work but doable.  As Drnick says a Chop saw is you're best bet.

Amazing ASCII artwork follows:


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TIMBER to trim
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[kahlid74]

Well, there's lot of ways, but it really depends on how big the piece of wood is, and how accurate your cuts are.  If it's a small piece (1*6*X) then a miter saw or chop saw is fine.  If it's a big piece (20"*40" of MDF at 3/4") then you can roll table saw however, if you have any sides that aren't even it becomes hard to use the fence.

SO what @shponglefan said is pretty much the go to method.  Attache a guide along the exact measurement you need and flush trim bit cut it.