Why am I crap at measuring?

[throbscottle]

It occurred to me yesterday, after I made 2 bits of wood into 4 bits of wood of close to equal size, that if I had actually measured the job, they would likely be worse than my "2 rough marks and guess". I've always been like this. It's not like I can't measure. I know exactly what to do and do it very carefully (kerf accounted for too) Somehow though the cut is never in quite the right place. I do it no matter what material I'm using, not just wood.
That's my moan for the day...

 

[Lons]

Need to go to Specsavers maybe.
Seriously though it's likely to be the position of your head over the cutting blade, I'd suggest you get someone experienced to watch as you cut and maybe put you on the right track.

 

[Sideways]

Get a decent 300mm and a 600mm steel rule - like the Japanese ones from Axminster, pearl chrome finished and really clear to read. Use them with a sliding stop. You position the stop in good light, mark with a sharp pencil or knife off the end of the rule and have repeatability across however many pieces you need because you only read the ruler once. Or set a fence stop on a mitre and do it that way. Or do the same thing using a sliding combination square when cutting short pieces.

Mark - cut - mark - cut -
Don't mark a stick into several sections and then do all the cuts one after another. That's bound to give you some long and some short pieces.

 

[Spectric]

I would always try and use stops on my mitre saw if I am needing to cut multiple pieces the same length, much better than measuring and marking each cut.

Also take into account the blade kerf, keep the cut on the correct side of your mark otherwise you will cut a bladewidth short each time.

 

[deema]

I really empathise with your issue, I’ve done it so many times. I now endeavour not to use any form of measuring device when making stuff, I try to always use a story stick. Just a length of batten that I place marks on which correspond to all dimensions. One side is for length and another is for width measurements.

For say windows and doors a couple of batons cut to the required length and width on site and checked in the reveals stops a lot of reaching for a Hamlet cigar! (Yes I’m old enough to remember the ads)

 

[throbscottle]

I used to like those ads too! Though I don't remember that particular one. Funny.
Anyway, lots of good advice there - thanks everyone.

 

[Bingy man]

What you need is a method such as mentioned above that works for you . Once you find your chosen method then stick to it and your confidence as well as your accuracy will grow . I’ve lost count of the times I’ve measured from the edge of a piece timber and then repeated it say 4 times only to find that I have four different pieces. For me it was not starting with a square end to begin with. 1st job is a quick check to confirm my t:saw or mitre saw is cutting true and square. Then as per @Sideways i prefer a Japanese type rule with an end stop . Also that old one measure multiple times and cut once . Also flip stops , mitre stops set up correctly will help prevent mistakes and improve your accuracy.

 

[throbscottle]

Yes, I will definitely give stops on the ruler a go. I think I've even seen designs to make your own. I like the story stick idea too - that's a cracker!
Neither of my powered saws can be set very accurately. Most precise aid I have is a wonderful old thing called a Jointmaster. Slightly disingenuous for me because I've had to learn to saw right-handed to use it effectively. Never mind, it's still brilliant.
Ironically I visit Specsavers quite regularly - repairing their computers, that is...
Nice looking rulers. Shame they don't have a shorter one. My 12" is losing it's markings and I have a 6" that's way too shiny. The metre one's good but often too long. Very often I use a tape, though. I'll go this week and have a look at those anyway.
Interesting thought about getting someone to watch me cut. Actually finding such a someone may be a problem, however...

 

[Ttrees]

Do you have a decent plane for the job, like a hefty no.5 1/2 or whatever?
A shooting board might be your answer.

To go along with this, an engineers square from axi for a tenner,
and a sturdy vernier calipers for making sure your stock is parallel is nice too, what's prob starting at about 20 quid.

Nice long stainless rulers can be bought cheaply locally if you've not got reason to buy a square from axi, a tenner or so for a fairly nice job, with markings on both sides, hopefully not too garish of a finish like the last silverline one I bought for a fiver.
Nice to buy in person, and find one with an accurate crisp end.

And to aid sight, an angle poise lamp from the Swedish warehouse for about 15 seem great value to me, for the results can be achieved that is...
The angle poise lamp with a 7.5" shade and no smaller, is an unmatched design if used well.
Perhaps some nicer ones of the same design exist, but the only level up from that is extremely fancy medical designs.
The slightly cheaper ones on the bay are actually tiny

Regardless of how good your lighting may be, it might not be much good if you're stooping over the work shadowing it.

Tom

 

[throbscottle]

*Sigh*. Nice things (and nice gsd!), but you underestimate the backwardness of my situation!

 

[Ttrees]

I didn't think my most used kit (bar possibly the 5 1/2 these days)
was particularly fancy stuff, I just posted what I thought I got good value from in regards to what quality you can get for the money.

I suppose mine, or another decently long bench could be seen as a bit much...
If I didn't have that, nor the space for one of such length, I would consider
something like Andrew Hunter's bench on fine woodworking channel on youtube,
but a bit longer to suit western style hand planing.
It's basically a sleeper or two on top of saw horses, in which the ends can be butted against the wall
to make a rigid floating top, which you could store vertically if necessary.

That's presuming you have space somewhere for that?

Tom

 

[thetyreman]

I use a marking knife when I need the highest accuracy, story stick/rod is a good idea too not only for consistency but you will save a lot of time.

 

[Suffolk Brian]

Do check that for a given length, all your measuring implements give you the same reading………….

 

[Just4Fun]

I now endeavour not to use any form of measuring device when making stuff, I try to always use a story stick.

Interesting. I have recently started doing something similar. I set the initial/major dimensions for a project based on what I think looks right, without ever knowing what that measurement is in mm. Then other measurements are based on that, with pieces being made to fit / match what I already have. This doesn't feel natural to me yet but I think it will become my normal way or working.

I am not very good at using a story stick though. Perhaps I don't really know how I should use one. For example, instead of marking the length of 4 table legs from a story stick, I cut one leg to the length I think seems right and then cut three more to match. I could see the benefits of a story stick if I wanted to make multiple items the same, but I don't do that. My projects are all one-offs, not mass-produced items.

 

[worn thumbs]

This needs to be emphasised,on two occasions I have found a rule to be inaccurate and I took them out of circulation.I trust Stanley tape rules and I trust Rabone steel rules that carry the phrase standard at 20 C.Others gain my trust if they compare well to those mentioned.Good tools to measure with and sharply defined marks to work to are fundamental to good work.While getting to the point where it becomes automatic,a woodburner is a handy thing for getting rid of the evidence.

 

[HappyHacker]

I have found a combination square good for marking up small measurements. Set the rule to the measurement and tighten the nut and use it with a marking knife. I have a 6" and 12" and a larger one I rarely use.

As has been said check your tape measures are all the same and chuck those that are inaccurate. I check mine against a metre rule both inside and outside so I know the little slider tab works ok. Also check the tab is not bent and giving a different reading depending on where on the tab the measurement is taken from.

Apart from the above I can give no advice as on occasions I am even worse. The amount of skirting/architrave I have wasted taking an inside measurement for a mitre joint and then using it as the outside measurement even when being careful!

 

[thetyreman]

This needs to be emphasised,on two occasions I have found a rule to be inaccurate and I took them out of circulation.I trust Stanley tape rules and I trust Rabone steel rules that carry the phrase standard at 20 C.Others gain my trust if they compare well to those mentioned.Good tools to measure with and sharply defined marks to work to are fundamental to good work.While getting to the point where it becomes automatic,a woodburner is a handy thing for getting rid of the evidence.

I've found how you use a ruler is critical, might sound a bit silly but there's a technique to getting it right every time, including how you push the pencil against it so there's no gaps.

 

[johnnyb]

situation accurate measuring is rare in my woodworking. the last time was when I was measuring to have some oak drawers made. there measurements would be accurate but if the drawer didn't fit it would be an expensive box it was n internal measurement as well. I cut a stick to be a nice fit then measured that with a steel rule. they fitted really well.

 

[johnnyb]

your problem sound like a cutting problem not a measuring one!

 

[throbscottle]

Thinking about it, many many years ago I compared a plastic ruler (one of the "shatterproof" ones, probably) to a steel one I had, and found the steel one wanting. So there's something in that. I have no idea what my reference was. Maybe another ruler.

I also use the method of "cut one, use that to measure the rest".

It's not so much a lack of space now, as lack of organisation, and with a lot of demands on my free time I just haven't had much opportunity to sort it out. Takes a long time when you have to move stuff to get to stuff which you also need to move to make a space for other stuff so you can fit in the stuff you moved first, but is now completely blocked by the 2nd and 3rd lots of stuff, which you then have to move again. Been a lot of that. The couple of things I was working on have been on hold since maybe August or September, combination of lack of time, daylight and good enough weather to put some stuff outside for a few hours. Oh well, it'll get there eventually.

I only have one tape measure. Cheap, but I have no reason to doubt it.

Nice tip about internal measurements!

Thetyreman - would you care to expand on that?

As to my problem being a cutting problem, not a measuring one. Well maybe, I don't know. I will definitely have to explore what I'm actually doing. Perhaps there'll be a lightbulb moment down the line. Or maybe I just need to make more stuff

Question: how accurate is "acceptable", in terms of tolerance?