Asher Guitars WD Music Products Amplified Parts Mod Kits DIY Nordstarnd Pickups
Asher Guitars WD Music Products Amplified Parts Mod Kits DIY Nordstarnd Pickups
Asher Guitars WD Music Products Amplified Parts Mod Kits DIY Nordstarnd Pickups

PLEK Machines (from zombie thread)

Discussion in 'Tele-Technical' started by conecaster, Aug 27, 2010.

  1. eamscray

    eamscray TDPRI Member

    Sep 10, 2010
    Berlin, Germany
    Bummer. I had customers like that when I was working at the mortuary.

  2. 4string

    4string Friend of Leo's

    Feb 11, 2010
    Central California
    I just read through (most) of this thread. Ever hear the old axiom 'Passing the point of diminishing returns'? One micron tolerance? For how long, until you breath on it? Oh wait, that would be more like when the air movement produced by blinking your eye hits it.

    It would be my experience that accuracy/tolerances below .001" on much of anything is pointless if there isn't a very good reason to strive for that degree of accuracy. I'm sorry, but the mere playing of a guitar is going to flex the neck along those lines by finger pressure alone.

    So WTF? Let me ask this: What tests the Plek's accuracy? You say only the Plek can determine what it has done? If the best physical tolerance testing equipment can't test to that level, that doesn't leave much besides lasers. How often is a Plek machine re-calibrated?

    +1 to 65FHL. I am a stone fabricator, and whereas I am not directly involved with manufacturing surface plates, I do know exactly how they are made and why high percentage quartz granites make the best and most accurate plates. Google expansion/contraction ratios to find out why, as well as a host of other reasons. As 65FLH said, 5 degrees F and microns are reeling on the dial.... and that's granite; near the bottom of the expansion/contraction ratio chart. Wood is up near the top.

    So I'm just wondering if when you pay your $150 to $275 for a Plek job, load yer Git in yer car and start driving, exactly how much per mile it is going to cost you before your frets are .0003" different from when they came off the Plek machine. Sorry. The laws of physics are what they are.

    Investing way less in one of Murrmac's leveling beams will give you a leg-up on accuracy. Murray and I both agree that less than .001" is overkill, but we know it's what people want.

    You can swat a fly or you can nuke it. It's dead either way. You might as well just swat it, because there will be another one to take it's place soon enough. Buzz-buzz-buzz...

  3. David Collins

    David Collins Tele-Afflicted

    Sep 28, 2009
    Ann Arbor, MI
    A point I again feel critical to distinguish is involving short range vs long range tolerances. Skepticism regarding how critical long range precision should be, and of claims of tolerances of .001" or less over the entire surface is quite justified. Of course necks will flex anywhere from several, to several tens of thousandths when a string is plucked, when a hand touches a neck, when the angle of the guitar relative to gravity is changed, or when the humidity changes 20%. So of course claiming absolute accuracy to an intended line of the fret peaks under a string over an 18" length to within a quarter or half a thousandth of an inch is of course simply unrealistic, as you pointed out. The guitar in use is a very dynamic system when in use, not static, and long range tolerances of this level are simply abstract in practical application.

    I feel however, that it is not entirely futile to aim for these tolerances in a static neck when you consider the importance in relative shape. Making sure that when the frets are dead straight under the high E, it is not pointless to aim for .004" relief under the D string, or .008" under the low E. Likewise, it is not futile to try to make sure that this relief is shaped as you would like, whether that be centered at the 5th fret, or a curve only in the first 5 frets leveling out to a flat plane from there on up, and roll off on the upper frets shaped in where necessary. Though a thousandth or two difference here won't make or break a setup, and is far beyond the range of movement of a neck in use, still aiming for as high precision as possible in it's static relative shape from treble to bass and end to end can translate to improved playability in real application. I agree in principle with what I believe you're saying though, in that if you're at .007" relief on the low E instead of .008", it's not going to make a terribly realizable difference. So I don't think we disagree at all on the point of tolerances to an absolute shape being accountable to anything more than a few thousandths of an inch at best, on such a dynamic system.

    Where I feel high precision is far more important however, is short range tolerances. This is where an error of .001" can have a very real effect on setup. Consider this - when a high E string is set at a height of .060" over the 12th fret, when you fret a note you can end up with just over .003" clearance above the following fret. If the limiting factor of your setup happens to be buzz on the fret following the note you are playing, then every thousandth of an inch discrepancy will have to be multiplied by 18 in increased saddle height in order to get the same clearance over the following fret as if they were perfectly level. So if you're third fret happens to have been taken a thousandth lower than the line between the 2nd and 4th, you would have to raise the saddle about 18 thousandths to get the same clearance, amounting to an increase of .009" at the 12th fret (about 15% increase in action).

    So while long range accuracy of .001" or less may be a bit presumptuous in real world application, tight short range tolerances can be much more realistic to hold, and arguably more important. I tend to place the point where precision looses it's real world significance closer to a quarter of a thousandth in short range tolerances, which if you are careful, tolerances of a quarter to a tenth of a thousandth in short range tolerances of immediately adjacent frets is not an unrealistic goal with traditional lapping methods. Controlling the long range shape of relief, even if only in terms of relative tolerances is the harder part to achieve (especially on necks that settle in to a different shape under string tension than they do with strings removed), and is where the Plek holds significant advantages over most traditional leveling procedures. I still maintain that with care and intention these long range standards can be achieved by hand, but it can be quite difficult, and the Plek certainly makes the job much easier and more reliable with less hassle.

    Main point though, yes, tolerances less than a few thousandths over the entire board apply only in its static state, yet when considering things varying relief of one string to another, where the relief is centered, etc, it can be a worthy goal to aim toward. In short range tolerances, such as alignment of any three or four adjacent frets, tolerances of a quarter to a tenth of a thousandth are much more achievable, and errors beyond this range can have a very real impact on the final setup.

  4. Stratelcaster

    Stratelcaster Tele-Meister

    May 17, 2010
    Twin Towns,MN
    If we would all take up the steel guitar we could put this silly stuff behind us.

  5. David Collins

    David Collins Tele-Afflicted

    Sep 28, 2009
    Ann Arbor, MI
    Okay, I dug out my old parts-caster that's been my test mule for crazy experiments and practice guitar for student work (it's already been refretted half a dozen or so times). I refretted it with stainless steel on Monday, and finished the dressing, nut, and setup today.

    I'd like to witness the Plek scan in person, and since Joe's shop is a bit of a drive I'm going to take it over to another friend's shop which has a Plek machine. Hopefully I can make my way over next week, and I'll fill you in on the results.

    I should say beforehand that though I'm confident in its accuracy to my intentions, it may not be in full agreement with the Plek's prescribed preferences. This board has a radical compound radius, but so long as the lines beneath each string are true I would think the Plek programming should have no objection to this. There is also a bit more fall away below the center strings which starts a bit earlier than the outer ones (I do have intentional reasons behind this). It's dead straight on the treble, continuing quite nearly as straight under the following treble strings, and increasing relief along the wounds, with a slightly larger step for the low E, though relief here is still a modest few thousandths. I'm not sure how this will comply with the Plek designers ideas of ideal relief for each string, but I'm quite confident that the lines from the scan will be accurate to my intentions in a very smooth and consistent manner.

    Actually, there is at least one very slight error around the 9th fret under the treble string, but so slight that I chose not to pursue correcting it. I'm somewhat curious if the Plek will even be able to detect it, as it is likely in the range of a .0001" inconsistency. There may be another one I spotted on the lower strings, but I'll have to go back and check. In any case, they are far from significant enough to affect playability.

    The current setup is around 1/32" at the 12th under the high E, just above 3/64" on the low E, and the nut slots are as low as they get. Of course this low action could rattle with a heavy hitter, but I get no buzz at all with my playing style, and can bend as far as you can push a string, three full steps on the G, with no rattle or choking.

    In any case, I'll try my best to get to a Plek near me and get it scanned next week. I'll keep y'all posted with honest results.

  6. Greg.Coal

    Greg.Coal Tele-Afflicted

    Aug 23, 2009
    Best test subject?

    From the PLEK site:
    "In the Virtual Fret Dress menu the operator can not only determine how much needs to be cut off from each fret but can also set the fretboard radius and amount of fall-off suited for the instrument or player."​
    I am going to ask you to explain your interpretation of this - though I know that you are not the instigator: how does the PLEK "set the fretboard radius .."?

    Is the radius not determined in the wood first? Or, does the text merely mean that it determines the radius and fall off and works accordingly? The website also says that the machine will cut the nut, too. I know you said you like yours as it is; would you allow a new nut to be installed for the purposes of the test should the program say that it's too low, for instance?

    I think you will be impressed with the ability of the device to characterize the neck and, who knows, you might come back impressed with the whole process. Do you have a backup constant radius instrument to bring?

    I have no position in this process - just curious.


  7. Ziggy

    Ziggy Tele-Holic

    Dec 10, 2009
    I am looking forward to hearing the results.

  8. MN Punk

    MN Punk Tele-Holic

    Feb 9, 2010
    Here's my take on it...

    Is a PLEK overkill? Maybe. So is a Gibson Robot guitar when you anybody can learn to tune up in under a minute or so. So is a CNC machine for a home-builder who wants to make Telecasters when a good table router and Kirn's templates from eBay will make one just as good as a genuine '52 if you know what you're doing.

    But as technology gets cheaper, it approaches the point where we're all just going to say, "why WOULDN'T you use it?"

    I can tune by ear just as I'm sure Scotty Moore did back in the day, but I use a stomp-box tuner on stage because it was only $50 used and it's convenient and I can adjust my guitar without performing that classic Chinese hit, "TU NING" for the entire audience. Also because it's 2010 for cripe's sake.

    A neck alignment using a PLEK machine or something very much like it will eventually become standard operating procedure for doing a professional setup, and people will look back at the information currently on the Fret-leveling sticky thread here in this forum and marvel at the fact that we used to use such a time and skill intensive method of making our guitars more playable.

    Someday, a push-button kiosk, small enough to sit in the back of a music store or be hauled along by pros on tour, will level, crown, dress, setup, and tune guitars, even re-string if needed, faster than a microwave cooks a bowl of oatmeal, and professional "guitar techs" will go the way of buggy-whip makers.

  9. David Collins

    David Collins Tele-Afflicted

    Sep 28, 2009
    Ann Arbor, MI
    Greg - The Plek obviously does not set the fretboard radius, as it does not shape the board at all (probably just a poor choice of words in the website description). It can I believe however, make minor adjustments in the dressing to adjust the radius slightly if programmed to do so, which has a little bit of room to vary from the board radius before difference in fret height becomes notable. I can't say how free the operator is to make these decisions, or how restrictive the programming may be, but it is a possibility with this type of machine.

    As to the nut height, I know the Plek can cut them very well, but there's simply no way that its measurements and programming could trump the judgement of a skilled luthier in this particular facet of setup. I doubt it will be an issue that comes up, but if it were to I would be more than happy to back up my position on ideal nut heights with a first hand demonstration and tutorial. Again though, probably a moot point, as I believe it will agree with my settings here. If it didn't it would be wrong, ;), and again I am quite confident I could back that argument if it came up.

    As to being impressed with the tool's capabilities, I already am. I know I often come across as being a critic of the machine, but in reality I am anything but that. As I've said, it is a fantastic design incorporating current technologies in to an application-specific tool, it's extremely well made, and it can deliver excellent results. The only point I constantly run in to the wall with people in discussions is not the quality the tool is capable of delivering, but the misconception that equal results are not achievable by other means. That's it.

    I may try to take a second instrument over as well, but honestly of all the guitars I own, very few are in one piece at any given time. The old cobbler with no shoes story - I rarely have time to work on my own instruments. Perhaps if I happen to have a customer job ready at the time, and the owner is okay with me taking it to be scanned, then I may take a second guitar. Or maybe I'll have my apprentice do a fret level on one of his to test out his work. I think this one should be fine though.

    Looks at this point like I'm not going to make it over this coming week though, so we'll just have to wait another few days.

  10. RodeoTex

    RodeoTex Poster Extraordinaire

    Sep 14, 2005
    Nueces Strip
    I can see the possible benefits of a PLEK tweeking to relative measurements. I can also understand how microfine adjustments are rather arbitrary when considering outside forces. I can agree that someday there will be a machine in every guitar store where you'll just hang you guitar in it and put in a few quarters.
    My question is, how much will it cost to undo it if you're not happy?

  11. murrmac123

    murrmac123 Tele-Meister

    Jan 25, 2008
    I am not quite sure what the much anticipated showdown, High Noon style , between David and the Plek machine is going to prove.

    Surely, the only viable testing method would be to take two identical Telecasters (Chinese imports preferably, straight off the boat) and for David to work his magic on one, and for the Plek machine to do its stuff on the other.

    The two instruments then get played by a panel of experienced professionals, the preferences noted, and evaluated by a competent statistician.

    That is how an experiment is conducted, IMHO.

  12. Colt W. Knight

    Colt W. Knight Doctor of Teleocity Ad Free Member

    Jan 21, 2007
    Tucson, AZ
    I don't think two guitars would be enough. You would have to have more data in order to have statistical significance.

  13. murrmac123

    murrmac123 Tele-Meister

    Jan 25, 2008
    I see where you are coming from, Colt, but, in fact, two guitars is "necessary and sufficient" (statistical jargon) for the purpose.

    The significance becomes greater, the larger the number of players , but there is no purpose served by increasing the number of guitars.

  14. Greg.Coal

    Greg.Coal Tele-Afflicted

    Aug 23, 2009

    Thanks, Colt. I'm a research scientist and it caught my eye, too. Repetitions.

    (But I try to leave that part of me behind when I am perusing the TDPRI.)

    I do believe that DC can do the frets and setup way better than my needs and, because I am pretty sure that he is good at it and the instrument that he brings in will be as perfect as it can get, I assume the machine will confirm that it is 98% or so within its spec. Or, whatever the value is.

    No one has mentioned, but I hope that PLEK will make the one or two that he brings in a freebie - because if David can confirm that, like a good physician, the PLEK above all does no harm, that in itself is a confirmation that it is for real.

    I have to say (I mentioned it elsewhere) that I eyeballed a bunch of tele necks in a GC recently and the USAs were so superior (straight and smooth) to the rest that the CVs, Squiers and MIMs were pretty much identical (lumpy). I don't know that Fender is using the PLEK or not - but I think this debate brings attention to a guitar neck's quality for playability (and true value).


  15. Colt W. Knight

    Colt W. Knight Doctor of Teleocity Ad Free Member

    Jan 21, 2007
    Tucson, AZ
    If I was presented only two guitars in a scientific proceedings, I would shrug it off as purely anecdotal.

  16. Nick JD

    Nick JD Doctor of Teleocity Ad Free Member

    I would also shrug off any data obtained by those participating in the experiment who did not play either the opening riff from Sweet Child of Mine or the first two bars or Stairway to Heaven.

    From every music shop I've ever been to, everybody knows a guitar cannot be adequately tested without those two songs.

    This is SCIENCE, not art. It matters not what you play but how many thousandths on a micron exist between that D note and Oh, Oh, Oh SWEET CHILD O' MYEEEEEYINE.

  17. PhatBoy

    PhatBoy Tele-Afflicted

    Mar 17, 2003
    OKC, OK
    Can anyone address the idea of the Plek Tech's ability?
    I'd give the machine a try, but it will only be as good as the operator.
    In general, can the plek overcome the shortcomings of the tech?


  18. Colt W. Knight

    Colt W. Knight Doctor of Teleocity Ad Free Member

    Jan 21, 2007
    Tucson, AZ
    Yeah, I don't think there is anything on earth that can overcome the operator.

  19. Nick JD

    Nick JD Doctor of Teleocity Ad Free Member

    Skynet became self-aware at 2:14 a.m. Eastern time, August 29th, 1997 :D.

    You people will all be eating your words when the PLEK Machines rise against us and we're all rendered to a bloody pulp a thousandth of an inch at a time.

  20. Greg.Coal

    Greg.Coal Tele-Afflicted

    Aug 23, 2009
    Black Box

    When I design systems for lab use, my ideal is the "black box": people can't mess it up, just push the "go" button.

    It's easy to say the machine is only as good as the operator, but I think that suggests a reasonable probability of operator screw-up. The operator mounts it in the machine, runs the first scan (I think he has to adjust the neck at some point - and the saddle on an acoustic). Since this so far is happening in better guitar shops a reasonable assumption is that a qualified person is on hand.

    Then he has to de-string and re-string.

    I was reading on TalkBass about a noteworthy bass maker (Lakland) having a PLEK installed in their Indonesian factory. You can imagine the advantage. The consensus (not scientific) is that the already great neckwork (these weren't inexpensive imports) was still great after PLEK arrived. These must be installed in US guitar factories, too - where the labor savings would be greater.


IMPORTANT: Treat everyone here with respect, no matter how difficult!
No sex, drug, political, religion or hate discussion permitted here.