Messages

5221

General Mach Discussion / Re: Help with ISO Metric thread form specifications

« on: December 29, 2009, 04:48:16 PM »

BClemens,
"Sorry I posted....must refrain.... right RICH?"

No.... i was just too lazy to look up stuff in the Machinist Handbook and i don't do much metric threading. Thus didn't want to miss inform you.  Some folks are happy that the nut goes on the thread tight, loose, or whatever!
The metric thread for a M profile is like an American National Standard thread for a sharp V but the tolerances are desgnated differently and of course the pitch and such are different.
certainly don't know them off the top of my head.
RICH

5222

Works in progress / Re: All in one lathe screen (Beta)

« on: December 29, 2009, 04:30:52 PM »

Hmm.....waite a minute, i just read page 3  again....i got it right! 
You guys are just trying to confuse me as usual. 

RICH

Sorry, Friedrich....sometimes we need help! 

5223

General Mach Discussion / Re: Help with ISO Metric thread form specifications

« on: December 29, 2009, 12:12:07 PM »

John,
Unfortunately if you want an Iso standard you need to pay for it unless you are a member of the orginization.  Even the public library has to pay for them.That's how those orginizations support themselves. I no longer have access to them. A set of all of the standard  books will fill a library.
Most of the info in the Threading on The lathe write up is for imperial threads but you may want to do a quick read of it. If you have a machinist handbook you can find what you are after.

The reason it is all so confusing is that everything is based on tolerance that is related to some class of thread and profile and how it's will be applied to what you are going to do with the threaded piece ( ie. maybe you are going to plate the thread ).

One of the things that screws up a thread is not accounting for the cutter tip radius. I usualy do a light finish cut with the threading tool, measure the turned diameter, then back the tool off the piece by the tip radius ( which i know or have measured ), set the major diameter to it max allowable , and base the depth of cut on .866P. Tip radius, even a sharply ground V is not truely "zero".
If all was perfect, the lathe system, the cutting action, setting of the tool, stock support, etc.....you should be able to be in spec.
But in reality "perfect" never happens, so recomend you try experiment some for experience.
RICH

5224

Works in progress / Re: All in one lathe screen (Beta)

« on: December 29, 2009, 11:18:50 AM »

Sorry about that, Brett .....Russ ......i get them mixed up .......Dosen't matter... comment still applies! 
RICH

5225

Works in progress / Re: All in one lathe screen (Beta)

« on: December 29, 2009, 11:09:55 AM »

True Brett, you just need to get little fingers! 
RICH

5226

Works in progress / Re: All in one lathe screen (Beta)

« on: December 29, 2009, 11:06:16 AM »

The only problem with a modified  screen is if somebody posts a question on use, you may not have a clue as to what they are talking about. 

I like creativity and the user posted screens provide choice.

I can feel the vacuum of screen design sucking me in, but still not letting go of the anchor. 

RICH

5227

Works in progress / Re: All in one lathe screen (Beta)

« on: December 29, 2009, 10:49:28 AM »

Hood,
Like you said, everybody works differently and will desire different things for whatever reason.
One thing for sure, seems like the original lathe screens don't satisfy the needs of a lot of folks.
The logic ( never seen anything posted about it) of the screens seems to be more geared to an OEM and doing multiple parts. Then when the average user does a one of a kind he finds the screens cumbersome.  

Do you have any insight into what Brian is thinking of doing to the Lathe screen for Mach4?

RICH

5228

General Mach Discussion / Re: Table Squaring Compensation....

« on: December 28, 2009, 07:00:49 PM »

Like Ray said, find yourself / borrow a good machinist square ( accurate one and not some piece of junk ) and make some measurements. I think you can shim it and get it acceptable. If possible take it over a friends if they have some precision stuff and do it there.  Fortunately it's a small machine.

RICH
 

5229

General Mach Discussion / Re: Crop Circles.... But Not Everywhere....

« on: December 27, 2009, 09:22:40 PM »

AT least your using a mill. Not to confise but there are four combinations that will create them on the lathe.
Should you ever venture there take a look at the ARC Motion wirte up in Members Docs.
RICH

5230

General Mach Discussion / Re: Rotary Encoder to DRO

« on: December 27, 2009, 09:14:03 PM »

?You want to use an encoder as an MPG? ie. Use an encoder so you can manualy turn it's shaft and thus move an axis.
RICH