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mpbush
09-18-2003, 01:34 AM
I don't know how to do layout work. When I attended classes on machining at a gunsmithing school that was one of the things I tried specifically to learn but the teacher I don't think knew enough to teach it.

Anyway, is there a good simple book on it. I realize it can be complicated but most of what I am working on just requires the basics.

Specifically, what I am working on right now is I want to do a drill jig for four holes. This will be used to drill holes in wooden grip panels for reproduction German MG34 Machinegun grips. There are two holes at the top and two at the bottom.

My "teacher" just had us use calipers and use the tips to scratch marks but I am not going to do that with my good calipers!

So, what are the 800 different ways to do this?

Michael

Oso
09-18-2003, 01:54 AM
Get your drill press an x-y table and stop worrying. Work right from the dimensions and never bother scribing lines. A rough pencil layout on the metal to ensure you don't get a tenth of an inch off is all you need.

They can be had for as little as $80 or so, and are the cat's meow for general close drilling. It won't make your press into a jig borer, but its way better than trying to hit the little cross-mark.

Mine cost about $70 and has a table 5 1/2 x 12.

Use a spotter drill before the actual bit.

CCWKen
09-18-2003, 02:12 AM
Yea, that layout fluid is a mess anyway. Spill it and everything is blue or red. Spray it and go on a buzz for a while. I use a Sharpie fine line most of the time. Punch, spot and drill.

randyc
09-18-2003, 02:19 AM
Although good layouts can be executed from carpentry tools (as an example), it isn't that costly to acquire nice layout equipment, such as:

granite plate
right-angle plate
vernier height gage
dykem (or equivalent layout dye)

The granite plates and right angles are available in many sizes, you may select the ones that accomodate your needs. A twelve-inch height gage is usually adequate for home shop usage. (When I say that these do not have to be costly, obviously I refer to imported devices.)

X-Y tables are definitely useful, but have limitations. The obvious limitations are travel dimensions but consideration also must be given to the hole sizes that need to be drilled.

Most drill presses don't have enough spindle travel to accomodate a large range of drill diameters without having to move the table.

When the table is moved, some means of regaining relative location is required. It can be troublesome -- this is a typical problem with mill/drills.

In any case, spotting drills can sometimes be eliminated by using screw-machine drills.

Evan
09-18-2003, 02:21 AM
I design my layouts on a computer, print it out on a really accurate printer and tape it to the work. Center punch and good to go.

randyc
09-18-2003, 02:33 AM
Well, I've also been using the surface plate less for layouts recently - AutoCAD printout, applied to the workpiece is a good expediency for most work ...

ibewgypsie
09-18-2003, 07:02 AM
I have drilled PCB's direct through a autocad drawing printed to size 1=1.. FUnny how the integrated circuits just pop right in the holes and everything fits just like in the drawing.
On my metal projects, I use the sharpie or pencil method mostly, punch the marks, drill with smaller pilot drill then bore to size with correct one.

David

Oso
09-18-2003, 10:03 AM
Printouts are OK, but you should be aware that the government forbids printers and copiers from being perfectly true to size. They are forced to have a size error. This may throw larger dimensions off. In a 14 pin dip IC you wouldn't notice. In the board mounting holes, you might.

This is to prevent (as much as possible) the copying and printing of our worthless currency (dollarettes).

People could find it, but machine money acceptors cannot detect that kind of copy as well.

SGW
09-18-2003, 10:10 AM
Try "The Starrett Book for Student Machinists." It talks about all that basic layout stuff.

But...I seldom do truly accurate layout. I do layouts close enough so I can tell if I'm really off when drilling/machining, but I rely on the accuracy of my milling machine to put the holes and surfaces where they are supposed to be.

GRH
09-18-2003, 10:43 AM
I use the same technique as "Evan" and then
use my mill/drill ( which I fitted with 1"
travel dial indicators on "X Y & Z" axis )
the paper is a great help to see if I am
way off especially if it's a odd ball hole
pattern.

Graeme

Evan
09-18-2003, 10:47 AM
Oso,

That is an urban legend.

I worked for Xerox for 23 years. The reason that copiers would make the copies slightly oversize has nothing to do with money. It is so that an image of the shadow of the edge of the original would fall off the edge of the copy. This avoids leaving a black line on the edge(s). On some machines they opted to make exact size for size copies and blank the edge out for about 1/8 to 1/4 inch instead. Many of the machines including the 9200, 9400, 1075, 1090, 6500, and many others would copy to exact size. That includes the color copiers.

Most printers today are extemely close to correct size and the biggest source of error is humidity change changing the size of the paper. If you need a really stable printout use film instead of paper. Even it is affected by humidity but not as much. My Epson 1200 will print to about .010" over 10 inches. That is .999 accuracy, good enough for most jobs. Also handy is that it prints up to 13"x19".

FYI, the government DID insist on one thing. All color copiers print an invisible serial number on all color copies. It is composed of a series of single pixel dots of yellow toner distributed over the entire print. It cannot be seen by eye even with magnification but it floureces under short wave ultaviolet. The manufacturers don't talk about this and when I worked for Xerox I had to sign a NDA saying I wouldn't either. All color copier serial numbers are recorded together with info on who purchased it. This no longer matters much as inkjets don't do this.


[This message has been edited by Evan (edited 09-18-2003).]

bspooh
09-18-2003, 12:18 PM
I bought a 30 dollar cheap pair of 12" calipers(made in china)..I use this pair just for scribing lines in metal...I don't want to use my nice calipers for scribing..It will still take a lot of scribing to wear out the tips...Thats the best advice I can give...To properly layout work, you need a height gage, maybe even a granite surface plate, a good compass..etc..all of this adds up in cost..just buy a cheap pair of calipers and some dykem, and scribe away...

brent

Oso
09-18-2003, 02:44 PM
Urban legend?

Maybe, maybe not....My source was actually a US treasury employee.......independently confirmed by an engineer who works for a company making coin and bill acceptors. Neither would go any further with the explanation....

I did notice that the copy error was different in the x and y dimensions, none in X , a small amount in Y.

That accorded perfectly with the information I had gotten.........

In any case the size is not perfect in general, whatever the reason.

Evan
09-18-2003, 03:26 PM
Oso,

The treasury employee probably believed what he told you was true. The reason the error is different in X vs Y is that in scanning copiers the optics determine the error in one direction (slight) and the optics PLUS the drive accuracy of the transports and optics drive (for scanning optics) determine the error in the other dimension (greater). With the introduction of xenon flash lamp optical systems, first used in the Xerox 9200 in the late 70's, these errors disappeared. In particular, the Xerox 1075 had less than .01% size error in x and y.

Even some of the scanning optics machines had a provision for "size-for-size" copying, as it is known. The Xerox 1038 copier when set to 100% default mode would copy at 102% to avoid the above mentioned edge line problem. But, if you selected 99% and then back to 100% it would produce a true 100% copy.

I assure you that there never was any truth to the story that the gov mandated that exact size copying not be possible. It has been available for over twenty years.

I also worked on coin and bill acceptors as some of the machines were coin/bill operated. The bill acceptors of the day used a number of density readings with photocells at strategic points on the bill. If the density reading didn't match the correct profile then it was rejected. Having an oversize copy would certainly cause it to fail but that is not necessary. It is nearly impossible to make a copy, B/W or color, that has the correct density at all points. Color copy toners especially have far different densities than printing inks. The Xerographic process has very poor dynamic range and tends to make dark areas much darker and light areas much lighter. There is no way it will match a printed item. In this case, size really doesn't matter http://bbs.homeshopmachinist.net//biggrin.gif



[This message has been edited by Evan (edited 09-18-2003).]

Evan
09-18-2003, 03:37 PM
There is one interesting story that is true.

Quite a few Xerox reps worked for the CIA during the 60s and 70s. They repaired photocopiers in the embassies of the east bloc countries. The photocopiers were fitted with a microfilm camera that snapped a picture of every document copied. It was made to look like a standard component of the machine and needed frequent "preventive maintanence". It would hold enough film to take several 1000 pics before changing. That was usually plenty and the service reps made sure the machines were not too reliable so frequent service was required.

[This message has been edited by Evan (edited 09-18-2003).]

darryl
09-18-2003, 09:13 PM
I sure hope the American Standard doesn't have this built-in faciliy. I'd hate to be a plumber working for the government. Every so often, it malfunctions, you have to get the plumber, he has to change a 'module'--- . Think of how many pictures of a-holes, oh, never mind.

dvk
09-18-2003, 10:17 PM
Harbor freight sells 6" dial calipers for around $7.49 I bought one and then I bought another one just lately, they come in a nice plastic case with liner and also prewrapped in oil paper and plastic bag, there taken care of during the packing process, accurascy, to me is exceptional, cannot complain about rerpeatability of a measurement, I like to use them for all kinds of layout and transfer work, Enco sells the granite surface plate 9"x 12" for around $18.95 extremely accurate for my kind of layout work, surface guage any where from $15.00 to $20.00 range Enco again, set of squares 3" 4" 5" $3.99 a set of three, harbor freight, look around youll find great bargains on layout equipment...

spope14
09-18-2003, 11:03 PM
A few notes:

1. An X - Y table with indicators. Good call, expensive, but good and will pay itself off with enjoyment and accuracy over the years. probably a couple of hundred dollars.

2. The only way your teacher taught was this? Ok, I am not there, but I teach layout, but also immediately move on as layout is a good way, but our machiones in this world almost eliminate the need but for getting close...BUT I do very precise layouts as I was taught to do so, and I do teach very precise layouts. Not second guessing, but stating a philosophy. Hate to say it, but after quarter one in my class, we forget where the dykem is but for required layouts (NIMS) or for general positioning layouts. Layout however, is a great art to learn, and I do love it dearly, and do it as a "craftsmanship" aspect in quite a bit of my work (or should I say as a hobby, I love it that much)

As for layout information, check some of the older text books for information, and some of the books through about 1995. Books such as "Machine Tool Fundamentals" kibbey et al, Machine Tool technology, both go into this in depth. NTMA has a book on layout, do not have it here on hand, but know it exists, have it at the school, bought in 1993. Drafting books can also help - believe it or not.

3. Good layout tools. Surface plate 12 x 12 = about $90.00. Angle iron 3 inch = about $50.00. Surface gauge = $70.00, good 6 inch machinist square - $40.00. This is a start. From there - dividers, hermaphrodite calipers, vernier height gauges, radius gauges, bevel protractors, protractors....on and on....I am sure my prices are high, but in the end in a general ball park between the "import" and "high end" goods. Good tools lead to years of enjoyment, better work, pride, and your own peace of mind.

4. I DO use my calpiers in layout. I use either layout dye thin coated and even, or better yet, a good sharpie marker thin or thick tip. Calipers are resilient, but you must beware NOT to push hard on the tips. My best set I avoid this on, but I have two Mitutoyos, and two starretts. LIGHT PRESSURE should ...and i say should as the qualifier...not burr or round the ends. Thus I refer back to the "light and even coat" and the sharpie marker, which both allow for very light pressure to make very clear marks.

Its all in the process, and in the future needs of your work. I have eventually spent the money years back, a bit at a time, and have never looked back. I know this takes time, but as I said, a bit at a time, and piece by piece.

Good luck, good question

[This message has been edited by spope14 (edited 09-18-2003).]

wierdscience
09-18-2003, 11:58 PM
I bought a cheap (China) 12"dial hieght gage about five years ago,It cost me $113.00,but it did save a lot of scrap.

I also broke down and bought an optical center punch,this has helped too.

Forget the dykem,use one of those fat magic markers,Dries lots faster,goes on thinner,and will wash off easy.

In this day and age a surface plate is so cheap you can't afford not to have one,I got a 18X18 Suburban and a 18x24 China and my Starrett straight edge can't tell the difference.

Herb W
09-19-2003, 01:15 AM
Re "a good simple book"

One possible candidate:
Book No.6 in the workshop practice series - Measuring & Marking Metals by Ivan Law

Haven't seen it myself. Anyone have it?

For a brief description http://www.wiseowlmagazines.com/Workshop_Practice_Series.html

Paul Alciatore
09-20-2003, 03:26 PM
spope,

I guess I'm an intermediate in my shop skill level. I have also worried about the best way to accurately locate holes and other features on workpieces.

I feel that any of the scribing methods I have read about are going to produce an error of a few thousanths. You can use a square or depth gauge set to +/-0.0005" or better by transfering the measurement from a good caliper. But then the line you scribe will not be centered on the accurately set edge. It will be offset by 1/2 the diameter of the tip of the scribing tool you use.

Likewise, if you use the caliper itself, one side of the line will be very close but it's center will be off. Even that "close" side of the line will not be exact because the caliper must be tilted to allow the edge to do the scribbing and that will introduce another error. Perhaps it will compensate to a certain extent, but you can never be sure how well.

The scribers used with height gauges are usually flat on one side to allow them to be brought into contact with the surface plate to zero the gauge. The other side is at a 45* angle. So, again the line scribed will be accurate on one side but the center will be off by an amount determined by the pressure used to scribe the line.

All in all, it seems to me that the best you can hope for when scribing lines in any of these ways is +/- 2-3 thousanths relative to the reference edge. The lines-to-line tolerance will be much closer if you always work form the same reference edge/surface.

Then, between center punching, spot drilling, pilot drilling, and final drilling how many more thousanths will it drift?

It seems to me that you have to consider the actual requirements before deciding how to go from drawing to the drilled/milled part. Many parts will be OK with a +/-0.005" error. Some will need the machined features to be held to tighter tolerances but not necessairly that tight to the edges. Others must be tight all around. I like the thought of laying out just to prevent 1/10" errors (one turn of the lead screw) and do this on may parts, using the lead screws for accurate placement.

If you have any thoughts on better layout techniques I would love to hear them. But it seems to me that the layout is just a rough starting point and the accuracy of the machines combined with good measurements during the work is the best way to produce accurate parts.

I also appreciate the comments about magic markers. I have layout fluid and do use it. But I've used the markers often and have been feeling a bit guilty about that. Now, I feel better.

Paul A.

[This message has been edited by Paul Alciatore (edited 09-20-2003).]

spope14
09-20-2003, 09:43 PM
I like and appreciate your response, and I will probably be long winded in my answer. Two things - Clarification of layout, and a better measurement technique for holes location with good tools for you.

On parts with any major accuracy requirements, I seldom do layouts as anything but a general positioning reference. I do layouts because I like the "artwork", and have been taught to do layouts in the past by some real "masters" in tool rooms, and thus I like to keep up the skill. BUT this is more as a hobby that I do layout. The idea of setting positional reference is a good thing though, especially for beginners, and even intermediates, though not a requirement.

I often see beginners,and over confident people forget things such as the "compensation" of edge finders when they locate holes. A good positional layout helps prevent this. When beginners find a slot location by touching off a tool on the edge (paper touch), this helps to prevent the potential error of forgetting to compensate for the cutter radius. Pockets, this helps to prevent the math errors when you position each cut. As you said, positional and dial errors.

Layout is not the end all of accuracy, but can prevent errors. It sure becomes obvious when you go to drill a hole after edge finding, and find your drill about .100 off in the X/Y axises - you immediately know something is a kilter. Same with a pocket that you thought you had figured, say with a 1/2 end mill, and with .250 to go, you find yourself almost touching the edge lines.

In CNC, I for years blew off layout. still do for the most part personally, because I have the competence and methods in my mind and practice to check positions before the cut. However, with beginners, this is a good way to check correctness of such things as fixture offset, radius comp, coordinates, you name it. Errors found immediately, metal saved, scrap prevented, time and money lost cut back, even with the additional time it may take. As you said, the "dial of the machine" errors. Good call!!!!!!

For very accurate hole locational checking, the measurement skills and good tools are a necessity. My favorite check is to use a #1 or #2 CD, punch just the point, and get out a gauge pin and either my calipers or a depth mic off the edge. Check locations by measure to the pin, comp for 1/2 the pin, and you have the hole loc. If you need to move, use two CD sizes up, and CD it right. Hold the CD right there up in the chuck as close as you can if you have to drill again to prevent float, tip drill, check it again. BUT only if you have the room to do two sizes up (example use a #1 to do the check hole, #3 to CD the actual hole). Just an idea. I also do as many "off center of the part" indicates and locational drilling as possible, for it is very easy to indicate center of a part with a .0001 indicator. You can also indicate edge with a .0001 indicator using a parallel clamped on the edge, and doing a "center indicate" on the parallel and "midpoint" the parallel, thus you have a very exact edge find - better than an edge finder. These are my common edge finding methods for my personal methods. Very seldom more than .001 off on my holes. You can use a .001 indicator to do this as well, and have excellant results.

Layout is a pretty exacting skill when done right. I did state the positional aspect when I discussed it before, and stated that after quarter one, we forget where the dykem is for the most part. Our machines, the DRO's, and the methods I teach give the student the skills to do without...but I do not prevent layout either.

The tilt of the caliper, for a positional reference layout, .003 to .005 is not a big thing. The drill sets very close by DRO or program, or is far off. It is a "eyeball reference" thing, not the "end all". BTW, a dial caliper is also not the best way to measure holes because of the "flats" on the nibs.

The best CNC man I know has 27 years doing mill and lathe work CNC, and is also a manual toolmaker - total time is 35 years. Several people in the shop he works in, and many other CNC people I know who also program, set-up the whole 9 yards do some type of elementary positional layout. better to do this and be right the first time than to screw up a part and go whoops.

Many schools of thought, only stating mine. Layout is optional to me, probably used less not more, but a great art and craft to know, and one that can be very useful. Indicating parts and edges is also a very fine art, and one that is good to practice and know, and one that makes my life very easy.

Taught by some great toolmakers from the old school, did it as well, but still learn from the new school people, and very glad to do so!!!!

Great responses to my post!!!! Thank you.



[This message has been edited by spope14 (edited 09-20-2003).]

darryl
09-20-2003, 10:55 PM
This probably goes without saying, but when using the mill's handwheels to position for holes, always approach the positions from the same direction, so that play is not added or subtracted from hole to hole, and make sure the gibs are adjusted for no slop. If you overshoot a mark, back up and come in again from the proper direction. Snug the gibs before beginning to drill, otherwise, the table can move around and all the accuracy of the leadscrews will be wasted anyway. This is an error I commonly make, not securing the table against movement, before drilling. Another problem related to this, at least on my cheap mill, is the handwheels tend to rotate on their own. If the handles are not at the top or the bottom, the vibration will cause the leadscrews to turn. This adds confusion to the process of positioning the x and y axis.

Locksmith
09-21-2003, 10:10 PM
OSO :
I don't know about the copy machine size prohibition;are you sure? I often copy parts and the copies are dead nuts on.
It sounds like an urban fairy tale to me.

Locksmith
09-21-2003, 10:12 PM
OOPS!
Sorry, didn't read the whole thread.

Oso
09-22-2003, 02:21 AM
Locksmith....

Evan sez the US government rule is a rumor, but I have yet to find one copy machine that does not distort by at least 1 or 2% in one dimension.

Either there IS a rule, or there are crummy optics, or its cheaper, or Evan's deal with coverage is correct. I don't know nor really care which, but I do NOT trust the dims of copied stuff, not most printers.

I have done a lot of 2x and 4x PC board work, and there you have to put in a scale on the art and get them to match it exactly at the film shop (not used much any more).
Copies and printouts were ALWAYS off undefined amounts, and two different copies might not be off the same amount, if the copier lens servos had to move due to a paper change etc..

MOST plotters would at least get the relative scales right. The absolute size was always off with them also.

Only a Gerber plotter or equivalent is worth a rat's behind for accurate PCB work.

Evan
09-22-2003, 02:33 AM
Oso,

I forgot to mention the very first Xerox "copier". It was called the Xerox Standard. It was introduced in about 1951. It was a copy camera on a bench. Instead of film it used the Xerographic process. Completely manual, a good operator could make about 1 or 2 copies per minute. The one I serviced in Victoria was used to make PCBs. It was absolutely perfect on size and scale and the toner could be applied directly to a copper clad board and made very good resist. These were widely used for prototyping PCBs many years after production was discontinued.

randyc
09-22-2003, 02:47 AM
Well, I've used the technique of printing AutoCAD layouts, full scale, and contact-cementing them to my workpiece. The practice has been infrequent but I have been satisfied with the results.

Oso has been consistent in his assertion that this technique may be inaccurate and it made me doubt ...

So I drew a rectangle in AutoCAD a few minutes ago, 6.5 x 9.5 inches. I printed it and measured the diagonal distance of the rectangle. It was about .020 too short.

Checked the X, checked the Y, the 9.5 dimension was short, 6.5 looked OK. Maybe this is an anomaly in my H-P printer.

Based on a sample of one, however, Oso's assertion has alerted me to a potential problem.

edited to add this postscript: I'll continue to use printouts for some purposes but probably won't trust them for accurate location .. e.g. center-punching the layout holes and using the drill press, instead of the milling machine.

[This message has been edited by randyc (edited 09-22-2003).]

Evan
09-22-2003, 12:34 PM
Most inkjet printers are accurate in the direction the print head scans. There can be significant errors in the paper feed direction. That will vary from printer to printer and depends on the type of paper feed mechanism used, the type of paper used and the humidity of the paper when printed. If the paper is freshly opened and then printed in a humid climate it will absorb water and expand considerably.

The printer I use for layouts is an Epson 1270 and it is very accurate in both directions.

If you do a lot of this you can buy Tyvek in a 60' roll for inkjet printers $$$$. It is waterproof and extremely dimensionally stable as well as tear proof.

Also, if your printer has a consistent error you can use a high end graphics program such as Paint Shop Pro to resize the image in increments as small as .001" in either axis, together or independently.



[This message has been edited by Evan (edited 09-22-2003).]

randyc
09-22-2003, 01:49 PM
Evan:

Next time I use AutoCAD to make a layout, I'll try re-scaling the axis that had error. May not be effective, however - might be dealing with the incremental limits of the stepping motor (or the number of bits abailable to control it).

But definitely worth a try, good tip.

Evan
09-22-2003, 02:14 PM
Randy,

It should work as long as the error is repeatable. The minumum step size is equal to the printer's maximum resolution capability in that axis. Most ink jet printers today can print over 1000 dpi in the feed direction meaning a step of less than .001" so scaling by +-.001" is possible. My Epson will print 1440x1440 so the minimum step is ~.0007

randyc
09-22-2003, 02:51 PM
A short but interesting excursion to the H-P website yielded the information that my old 930 has 600 dpi resolution.

If I assume that resolution is directly related to accuracy (not necessarily true) and if the error is cumulative, this could amount to as much as .015 over nine inches.

Additionally, there is a specification on paper skew of +/- .006. H-P didn't qualify this - dunno if they mean +/- .006 per inch or over the sheet of paper.

I guess I'm left with some uncertainty about the accuracy of my printer for layout work but will still try adjusting the scale next time I do this.

Of course I could have already printed something and measured it in 1/3 the time I spent on the H-P website :)

Oso
09-22-2003, 06:40 PM
With our old plotters, there was a "grit roller" that grabbed the paper or drafting film.

When that got worn, the paper or film would slip, and there were some interesting errors that could be hard to catch. They were NOT repeatable.......

Hard to beat a height gage and scriber on a granite flat. And nothing gets gummed up in the cutter either.

brunneng
09-22-2003, 10:31 PM
For those using AutoCad and I haven't looked for this on the version I'm using now (R13) BUT:

You should be able to go to the configuration settings and there should be a printer compensation you can do.

In vers 9 you would print something, a square or rectangle. Then run the compensation in setup and it would ask you what the size should be and what the size actually printed was and it would then build a correction factor itself for that printer. After that the printouts were as accurate as I could measure on an HP Laserjet 5L. I would print as large a rect as possible using the thinest line to get the smallest measure error factor.

Check for this setting in your versions. It should be there.

randyc
09-22-2003, 10:53 PM
brunneng, mighty slick idea, I'll try that next time I open AutoCAD ! Beats intentionally distorting the scale every time that I print.

Thrud
09-23-2003, 04:05 AM
Oso
What Evan did not tell you is that color copiers can recognise real money and will not reproduce the colours accurately - even with adjustment of toner values. They will accurately reproduce the notes at 150% blowup minimum. It should be noted (pardon the pun) that any idiot that cannot tell real money from photocopied crap is a moron. Real money has the ink pressed into the paper (indelio (sp) process). Real money has watermarks, magnetic ink, security threads, and dozens of other security features that are kept from the general public.

Evan
09-23-2003, 12:21 PM
Thrud is correct, at least for the digital color copiers. The first color copier from Xerox in the 70s, the 6500, was analog and did not have any security features. It scared the crap out of the gov. Thrud, you might think that anyone can tell the difference but it's not so easy in a dark crowded noisy bar when you have a wad of bills in your fingers and the "money" is old and wrinkled and slightly damp and you are in a hurry. BTW, the process is "intaglio".

Oso
09-23-2003, 02:46 PM
the issue was B&W, early bill changers didn't know the difference...........later ones needed color, leading to your scenario.

As far as idiots, do I really have to explain how many there are? And how idiotic they are? And how much the average clerk looks at each piece of money that passes thru their hands in a day.....?

Think of the old counterfeiting deal where you split a larger bill DOWN THE MIDDLE and put the two halves of a smaller one on it. If folks didn't turn it over AND LOOK AT IT, it would pass, since it was actually a real bill, just not all of it.

brunneng
09-23-2003, 05:28 PM
Yep, the cashier is probably the couterfeiters greatest friend.

I recently bought some DVD's at a Circuit City store and paid with a hundred. The girl took it and didn't do a single check on it, barely glanced at it at all. It could have been single sided, no water mark, no color ink, no band and probably bugs bunny's picture on it for all she did. Didn't even pen it.

I like the Austrialian money. Plastic not paper with a clear window. I like the plastic idea because paper money is one of the dirtiest, bacteria ridden surfaces you're ever likely to touch.

Thrud
09-24-2003, 05:19 AM
Evan:
You are right - "intaglio". Excuse my brain fart. http://bbs.homeshopmachinist.net//eek.gif

Oso

I have had to give money back to cashiers - pay with a twenty and they give back change for $100. I can't in good conscience keep it. Many places force the cashiers to cough up for errors.

I love chewing some sales idiot (the snotty know it alls) out when their bosses are standing right behind them. I walked into a Jaguar store once in a t-shirt and holey pants to buy a new v-12. Bastard treated me like crap - so I tore him a new one. The manager asked what the problem was and I handed him my credit card - "write it up". When they were done and the CC was approved I told them I changed my mind because the salesman was treating me like crap and left.

[This message has been edited by Thrud (edited 09-24-2003).]

wierdscience
09-24-2003, 09:32 PM
Ya,talk about cashiers,I went to McDonalds the other day and my bill was $6.50,I gave the kid $11.50,what did I get back,nothing,I tapped on the glass,he came back,I told him I gave him a 10 ,so then what does he do,he gives me four ones back!After a thirty minute math lesson he finally got it right http://bbs.homeshopmachinist.net//biggrin.gif

A ccroding to the treasury its the paper that is the dead give away,some students were counterfiting 20's and 100's that passed everytime,their technique,use artists scetch tablets,they are made from cotton lint and feel the same as the real deal.

brunneng
09-24-2003, 10:04 PM
Yeah, I've seen the shows that make a big deal out of how special the paper is but just how special could it be. I'd bet most any analysis lab could tell you exactly what it's made of. Bleach it and rip a section out.

I'd also bet most people couldn't tell whether the red and blue fibers are embeded, on the surface or drawn on.

A counterfeiter can always find a place where they know the person isn't going to check money right. Try most fast food places - anywhere there's a fast, high cash turn over rate run by kids who hate their jobs.

The treasury dept even admits that if you were to counterfeit a small batch and used it very quickly that you would most likely never get caught. Lovely.

Plus those are mixed in with the billions printed by other countries - Columbia being a biggy, if not the biggest with China right there too. Two days before the new $20 came out to Americans they found fakes in China. That's fast, but hey, that's what we expect from there right? Anything we can do they can do faster and cheaper http://bbs.homeshopmachinist.net//wink.gif as the story goes.

Footnote: I know that not all chinese, columbians, etc... are involved or are criminals.

docsteve66
09-24-2003, 10:12 PM
WeirdScience: I do what you did (try to get back a five, ten or two quarters) to avoid a bunch of loose stuff. I have been fussed at a few times (gasoline stations and places where they don't have a computer) I finally decided to keep the excess if, after I look at it along time, they don't catch on. Most times, I wait to see how they re-act- if they are nice I give it back, if they are defensive, I say ok bub, you gave me too much and put it in pocket.

. And if they "short" me I don't take the change or I make damn sure to keep the hands in view. Even banks can not make change any more. Must be the new math.

What we used to call a short change artist must make a fortune these days.
Steve

Jaymo
09-24-2003, 11:37 PM
Speaking of shortchange. My wife and I ate at a food place the other day. I won't name names but they rhyme with tonic. Well, I was going to give a $2.00 tip to the girl who brought us our food, until she shorted me a dollar. At the time I was too tired and hungry to fight about it. I just figured she screwed herself by ensuring that she only got half what her tip would have been.
Anyway, I know nothing else, so I think I'll go to bed.

Thrud
09-25-2003, 02:48 AM
brunneng:

There was a big run on funny money up here two years ago - professional printers where at it. As a result many merchants and banks now have UV lights and chemical pens for separating the good from bad. The banks even taught classes on counterfeit detection to business customers that asked.