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Height Gauge Survey

Spyderedge

Titanium
Joined
Aug 28, 2013
Location
NY
With a machine deal, I am picking up a Starrett vernier height gauge and medium sized quality american made granite plate for $50. It's a no brainer, but it got me thinking about layout and machining to scribed lines.

How many people still machine parts to decent dimensions (.01")using only layout lines? With the mass popularity of DRO's and all I have to ASSume that most people just read numbers on a screen to rough out dimensions than look at layout lines. Then again when your tired numbers on a screen get jumbled around, while lines on a part never move.

Just wondering :scratchchin:
 
Some jobs just work better if you do a line layout on the stock. I band saw and belt sand contours using lines on the stock, for instance. I accurately position parts for drilling on my vertical mill using a centering microscope to locate on crossed height gauge lines on the part. I think a DRO would not help to get that first hole right on the crossed lines, but would be fine for other holes that reference the first hole.

Larry
 
I often put a few layout lines on expensive stock or parts, just for verification.. Saves doing something stupid like missing a location by .100, or even a full inch.. I will admit, I often use a crappy old dial caliper for scribing..
 
How many people still machine parts to decent dimensions (.01")using only layout lines?

I'd like to see someone do that consistently before believing it. I'm assuming you mean ±0.01" I'm not saying it can't be done but it'd be risky sending it to a customer without measuring just to check it.

±0.01" can easily be checked with a caliper.
 
Maybe not so much on parts made from solid, but layout lines can be very helpful on castings. Sometimes prototype or short run parts don't have the casting locators quite where they belong, or there was an engineering change without a pattern change and the machining needs to be shifted to ensure all the holes are in the casting. And sometimes you just need help visualizing the part when it has all that extra material around the outside.
 
I'd like to see someone do that consistently before believing it. I'm assuming you mean ±0.01" I'm not saying it can't be done but it'd be risky sending it to a customer without measuring just to check it.

±0.01" can easily be checked with a caliper.

I ran a job not too long ago milling a parts length to 8" and they all ended up at 7.96" - 7.99".

Scribed some lines, and with a magnifier I milled a pocket in a block, I could see the endmill just take out the line as I cranked in the last thou, so it can be done. With 7x mag .01" looks like a mile.
 
I ran a job not too long ago milling a parts length to 8" and they all ended up at 7.96" - 7.99".

I use a Sharpie for single cuts at the horizontal saw and do better (not kidding).
At the vertical bandsaw use masking tape.(not kidding)
 
I ran a job not too long ago milling a parts length to 8" and they all ended up at 7.96" - 7.99".

I use a Sharpie for single cuts at the horizontal saw and do better (not kidding).
At the vertical bandsaw use masking tape.(not kidding)

Well......good for you?
Not to be rude or anything but you must have a better saw than I do.
If you are going to talk the talk at least give us proof :D Comparator stand with fine indicator tip.....come on, lets go! :D
 
Try it and see,,I don't have to prove nothing,I was (a little bit ass-smart) way trying to pass some useful info your way.
Instead of a scribe line take some colored masking tape and put on your metal (especially handy for long cuts) and as your feeding the metal in the band saw,just kiss,or almost kiss the tape.You will be surprised at how well this works.Also a lot less eye strain than a scribed line and you will cut faster as a result.
Sharpie makes an extra fine tip.There again try it.
Ain't no Black Magic,I was just explaining a few tips.Especially useful for saw work.
 
Try it and see,,I don't have to prove nothing,I was (a little bit ass-smart) way trying to pass some useful info your way.
Instead of a scribe line take some colored masking tape and put on your metal (especially handy for long cuts) and as your feeding the metal in the band saw,just kiss,or almost kiss the tape.You will be surprised at how well this works.

I'll have to try that, thanks for the info.
Another reason why I milled that sawcut on those parts, they were showpieces and a saw cut would've looked like a hack job. And I'm one notch above a hack :)
Take care
 
I ran a job not too long ago milling a parts length to 8" and they all ended up at 7.96" - 7.99".

Scribed some lines, and with a magnifier I milled a pocket in a block, I could see the endmill just take out the line as I cranked in the last thou, so it can be done. With 7x mag .01" looks like a mile.



I didn't even brag about being within forty thou when I was a carpenter.... :confused:
 
I didn't even brag about being within forty thou when I was a carpenter.... :confused:

Not bragging, just stating facts. I have no work to brag about, I even messed up a cube inside a cube the other day. The inner cube just fell out!

Seriously, mill to a line under magnification, you'll be surprised.
 
whether its the right tool obviously depends on the job....when it is its a fast way to make holes

a height gauge (dial or digital is easier on the eyes and so speeds things) and optical centre punch will easily get you better than .01". more likely with a couple of thou which is plenty good enough for drilling.
 
I use to be able to read a pocket rule measuring turned diameters and be within +-0.1mm. Was a game me and 2 other machinists use to play whats surprising is how naturaly it comes after just a few days. You don't so much divide up the graduations and guess, just look at were the edge is bettwen the mm marks make a decision based on the number of 10/ths you think it is proportionaly. Its kinda blew my mind at first just how good and easy it was to do. Whats even stranger and least bettwen the 3 of us we all found it easier to use a 1mm graduated scale to do the eye balling with, 0.5mm graduations were to crowded and not clear enough.

As to lengths, scrided lines and 4 thou is pushing it a bit, but certainly 10 is easily done, just takes a sharp scribe and a cutting process that is not throwing a burr. Pre DRO a harrison lathe has no z so all lengths were done to scribed marks when out of the range of the topside. So long as your marks are accurate and your cheacking your self with something like a vernier its soon possible to develop a feel for it.
 








 
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