There is a standard for straight edges, at least in Europe, called DIN 874. It provides four grades, 00, 0, 1, and 2. These describe flatness tolerance as a function of length. You can look for products that are certified to meet these grades.
thumbs up and bought through your affiliate link. I've been trying to find a good straight edge for DAYS and couldn't figure out how to test one if I got it. Your jig test made perfect sense to me, I like your channel (I've been subbed for a bit) and you seem to not recommend garbage so I took the plunge (pun intended). :) Thanks for this and all your content!
Hi, this is not correct way of measuring flatness. With dial indicator like that you measuring width variation of the tool a certain spot. Tool might be slighly bent from end to end but you get accurate measurements with the dial. If you want to see if your surface is flat / straight from end to end or you would need another perfect flat surface put them together and look against the light if you see any tiniest light passing through.
@@HighlineGuitars You measure width of the tool at the certain spot. Straightness is the edges are bulletstraight from end to end. If there is a slight curve it won't be noticed when measuring at single spot at a time even moving the object.
A quite delicate topic... Diving into the world of guitar making and the desired absolute precision one has to be very aware of not getting lost. The most truest/straightest "level-tool" would be a level/measuring-beam made of granite, as used in machinery and cnc-technolology (IMO! But also expensive & heavy!).. one has to bear in mind that even the temperature of your hand will affect the accuracy of a such precise tool if it's made out of metal! (Aluminium???) Anyways: As long as the guitar(Neck) material is wood, a lot of other variables have to be considered (humidity/quality/density/flexibility/ETC...). Furthermore will the installation of the frets, the finish and the years under the force of the strings tension affect the "perfect straightness" which we try to achieve so hard (by buying expensive tools on and on)... So it's a matter of relation. Some of the best instruments are still realized by luthiers only using hand tools such as planning iron and scrapers (with 'perfect' results). So there's much more potential in the human eye and hand that we'd might believe. And yes - there is a (german/DIN) standard for straightness/accuracy. All words meant positively!! Keep up the good work, sir! Kind regards!
I haven't read all the other comments but I noticed that your dial indicator is measuring across the width or span of the bar or straight edge this will not give you the total run out of the length of the bar which is what you need I would assume to be accurate on measuring the fretboard you want to know that in a straight line the edge of that straight edge does not deviate or wander in theory you could have a banana of equal with and use that same gauge to get the same inaccurate reading that you obtained I'm sure the piece is accurate but you're demonstration did not accurately represent what I understood you were trying to convey but anyways keep up the great work I love to see all your videos
Machinist here. You would most definitely be better off buying a new straight edge. The cost could be well into the hundreds. Much of a job's setup charge can be attributed to coming up with custom workholding, and holding onto a relatively long, thin part such as a straight edge would be somewhat difficult. We'd be talking about two or three perfectly aligned vises, possibly requiring a specific profile milled into each set of jaws. What seems like a simple operation can get pretty expensive, pretty fast.
This is quite "over the top". A precision straight edge is great for checking really critical surfaces such as engine cylinder heads etc. But not necessary for wooden items and guitar, just use a good quality metal ruler, or any regular straight edge. Easy way to check is while in store hold two together to check edge straightness. I usually like your videos and no, I am not troll.
take a 1/4 inch plate glass mirror as the FLAT surface & sandpaper the straightedge you have on it. my straightedge from stewmac was out by over 4 thousandths on each end from flat. i complained and stewmac just replied that i could return it. what a scam. anyway, yours is out of flat by a small amount and needs the sandpaper treatment. nothing truer than plate glass mirror, take a look!
There is a standard for straight edges, at least in Europe, called DIN 874. It provides four grades, 00, 0, 1, and 2. These describe flatness tolerance as a function of length. You can look for products that are certified to meet these grades.
The only ones I could find are the Kinex line of straight edges, which are EXPENSIVE.
thumbs up and bought through your affiliate link. I've been trying to find a good straight edge for DAYS and couldn't figure out how to test one if I got it. Your jig test made perfect sense to me, I like your channel (I've been subbed for a bit) and you seem to not recommend garbage so I took the plunge (pun intended). :) Thanks for this and all your content!
That's awesome @M2Texas. Thanks for sharing your experience with this straightedge. I use mine every day!
Thanks for the info , Chris !!
You bet!
Hi, this is not correct way of measuring flatness. With dial indicator like that you measuring width variation of the tool a certain spot. Tool might be slighly bent from end to end but you get accurate measurements with the dial. If you want to see if your surface is flat / straight from end to end or you would need another perfect flat surface put them together and look against the light if you see any tiniest light passing through.
I'm not measuring flatness. I'm measuring straightness. This is the method we used at NASA.
@@HighlineGuitars You measure width of the tool at the certain spot. Straightness is the edges are bulletstraight from end to end. If there is a slight curve it won't be noticed when measuring at single spot at a time even moving the object.
@@Stu66orn ruclips.net/video/k6GTZrcoWEM/видео.html
I agree. You would get the same results measuring a hoop.
@@williamjones3616 You can't see the whole test rig (my fault). It works similar to a bicycle wheel truing stand. Sort of.
I am tempted to send one of these to a machine shop to have fret grooves machined in it for adjusting truss rods
You can grind the notches with a Dremel.
A quite delicate topic... Diving into the world of guitar making and the desired absolute precision one has to be very aware of not getting lost. The most truest/straightest "level-tool" would be a level/measuring-beam made of granite, as used in machinery and cnc-technolology (IMO! But also expensive & heavy!).. one has to bear in mind that even the temperature of your hand will affect the accuracy of a such precise tool if it's made out of metal! (Aluminium???) Anyways: As long as the guitar(Neck) material is wood, a lot of other variables have to be considered (humidity/quality/density/flexibility/ETC...). Furthermore will the installation of the frets, the finish and the years under the force of the strings tension affect the "perfect straightness" which we try to achieve so hard (by buying expensive tools on and on)... So it's a matter of relation. Some of the best instruments are still realized by luthiers only using hand tools such as planning iron and scrapers (with 'perfect' results). So there's much more potential in the human eye and hand that we'd might believe. And yes - there is a (german/DIN) standard for straightness/accuracy. All words meant positively!! Keep up the good work, sir! Kind regards!
I haven't read all the other comments but I noticed that your dial indicator is measuring across the width or span of the bar or straight edge this will not give you the total run out of the length of the bar which is what you need I would assume to be accurate on measuring the fretboard you want to know that in a straight line the edge of that straight edge does not deviate or wander in theory you could have a banana of equal with and use that same gauge to get the same inaccurate reading that you obtained I'm sure the piece is accurate but you're demonstration did not accurately represent what I understood you were trying to convey but anyways keep up the great work I love to see all your videos
correct, highline don't know what he is yappin' about. we will fix it so he knows
What does it cost to ‘regrind’ a 36 inch straight edge. Perhaps that called lapping maybe
I have no idea. Probably more that the cost of a new straight edge.
Machinist here. You would most definitely be better off buying a new straight edge. The cost could be well into the hundreds. Much of a job's setup charge can be attributed to coming up with custom workholding, and holding onto a relatively long, thin part such as a straight edge would be somewhat difficult. We'd be talking about two or three perfectly aligned vises, possibly requiring a specific profile milled into each set of jaws. What seems like a simple operation can get pretty expensive, pretty fast.
This is quite "over the top". A precision straight edge is great for checking really critical surfaces such as engine cylinder heads etc. But not necessary for wooden items and guitar, just use a good quality metal ruler, or any regular straight edge. Easy way to check is while in store hold two together to check edge straightness. I usually like your videos and no, I am not troll.
$25 for a precision straight edge. An unnecessary luxury? Maybe. However, I would want the guy making my $4,000 guitar to use one. 😉
But here the author is talking about a calibration ruler , and the more accurate it is , the undoubtedly better .
take a 1/4 inch plate glass mirror as the FLAT surface & sandpaper the straightedge you have on it. my straightedge from stewmac was out by over 4 thousandths on each end from flat. i complained and stewmac just replied that i could return it. what a scam. anyway, yours is out of flat by a small amount and needs the sandpaper treatment. nothing truer than plate glass mirror, take a look!
I have a bunch of plate glass mirrors. Not one of them could be used as none of them are true.