Not an even cut

Not an even cut

Postby Gunny Rogers » Sat Sep 08, 2018 3:43 am

While etching glass I discovered something unusual. I am not cutting on an even plain. For instance, On a piece of glass I was trying to etch the capital letter "R". on the first attempt the only thing that was etched was the slanted part of the R. If it was even all the way across the letter it would have been OK. But I tried six times to get the whole letter to get etched, each time attempt I lowered the bit, but even at the sixth attempt I wasn't satisfied with the letter. Is there some adjustment that I can make to make the machine cut level?
Gunny Rogers
 
Posts: 20
Joined: Sat Aug 22, 2015 1:41 am
Model of CNC Machine: 141001

Re: Not an even cut

Postby highpockets » Sat Sep 08, 2018 3:53 am

What bit are you using? What depth of cut are you using?
John
Maker of Chips
User avatar
highpockets
Vectric Wizard
 
Posts: 1775
Joined: Tue Jan 06, 2015 4:04 pm
Model of CNC Machine: PDJ Pilot Pro

Re: Not an even cut

Postby Rcnewcomb » Sat Sep 08, 2018 5:06 am

Have you leveled your spoilboard recently? If not, that might help.
- Randall Newcomb
10 fingers in, 10 fingers out - another good day in the shop
User avatar
Rcnewcomb
Vectric Wizard
 
Posts: 3071
Joined: Fri Nov 04, 2005 5:54 am
Location: San Jose, California, USA
Model of CNC Machine: GCnC/WinCNC

Re: Not an even cut

Postby 4DThinker » Sat Sep 08, 2018 10:40 am

The bit may be slipping up as you cut. Glass is a very hard surface, and may be resisting more than your steppers, or bit tightness can handle. Just a thought.
4DThinker
Vectric Wizard
 
Posts: 1122
Joined: Sun Sep 23, 2012 12:14 pm
Model of CNC Machine: CNC Shark Pro

Re: Not an even cut

Postby Gunny Rogers » Sat Sep 08, 2018 3:34 pm

1. I'm using a diamond tipped bit at a depth of .001. As I said I get only a partial etch on the glass.

2. How do I level the "spoilboard"? I haven't seen or heard about this adjustment. Please enlighten me as to how to level my "spoilboard".

3. I'm very meticulous about tightening my bits so I don't think that is the problem.
Gunny Rogers
 
Posts: 20
Joined: Sat Aug 22, 2015 1:41 am
Model of CNC Machine: 141001

Re: Not an even cut

Postby SteveNelson46 » Sat Sep 08, 2018 4:12 pm

Gunny Rogers wrote:1. I'm using a diamond tipped bit at a depth of .001. As I said I get only a partial etch on the glass.

2. How do I level the "spoilboard"? I haven't seen or heard about this adjustment. Please enlighten me as to how to level my "spoilboard".

3. I'm very meticulous about tightening my bits so I don't think that is the problem.


It's not an adjustment. It's a procedure to skim a small amount of material off of the top of your spoilboard so it is co planar with your router/spindle. YouTube has lots of different examples. Just search for "Leveling The Spoilboard"
Steve
User avatar
SteveNelson46
Vectric Craftsman
 
Posts: 258
Joined: Wed Jan 04, 2012 2:43 pm
Location: Tucson, Az.
Model of CNC Machine: Carvewright

Re: Not an even cut

Postby FixitMike » Sat Sep 08, 2018 4:35 pm

Is your diamond tipped bit spring loaded? If so, you can use a much larger engraving depth, and the end will move in and out to suit the precise height of the material you are marking. Very, very, few spoil boards will be parallel to the gantry movement to within .001". Myself, I start with a depth equal to half the total spring movement and change it if necessary.
Good judgement comes from experience.
Experience comes from bad judgement.
User avatar
FixitMike
Vectric Wizard
 
Posts: 1421
Joined: Sun Apr 17, 2011 5:21 am
Location: Renton, WA USA
Model of CNC Machine: Shark Pro Plus (modified)

Re: Not an even cut

Postby mtylerfl » Sat Sep 08, 2018 4:54 pm

FixitMike wrote:...Myself, I start with a depth equal to half the total spring movement and change it if necessary.


Good tip, Mike. I don’t think I’ve heard that one before (ie, starting with depth of half spring travel).
Michael Tyler

carvebuddy.com

facebook.com/carvebuddy

-CarveWright CNC
-ShopBot Buddy PRSAlpha CNC
User avatar
mtylerfl
Vectric Wizard
 
Posts: 3233
Joined: Thu Jan 29, 2009 3:54 am
Location: Brunswick, GA
Model of CNC Machine: -CarveWright CNC -ShopBot Buddy PRSAlpha

Re: Not an even cut

Postby FixitMike » Sat Sep 08, 2018 6:00 pm

mtylerfl wrote:Good tip, Mike. I don’t think I’ve heard that one before (ie, starting with depth of half spring travel).


I ran some tests with a diamond drag bit on acrylic. There did not seem to be much difference in the appearance with different pressures. So it apparently is not an important setting, at least with acrylic.
Good judgement comes from experience.
Experience comes from bad judgement.
User avatar
FixitMike
Vectric Wizard
 
Posts: 1421
Joined: Sun Apr 17, 2011 5:21 am
Location: Renton, WA USA
Model of CNC Machine: Shark Pro Plus (modified)

Re: Not an even cut

Postby Gunny Rogers » Sat Sep 08, 2018 9:05 pm

First off I don't have the equipment to shave off .001 of the spoilboard. I will got on face book and looks at some of the ways that on there. Maybe I'll just place a couple of sheets of paper under the low side of the material and lift it, hopefully that will level it enough.
Gunny Rogers
 
Posts: 20
Joined: Sat Aug 22, 2015 1:41 am
Model of CNC Machine: 141001

Re: Not an even cut

Postby mtylerfl » Sat Sep 08, 2018 10:37 pm

Gunny Rogers wrote:First off I don't have the equipment to shave off .001 of the spoilboard. I will got on face book and looks at some of the ways that on there. Maybe I'll just place a couple of sheets of paper under the low side of the material and lift it, hopefully that will level it enough.


You MUST purchase a spoilboard cutter to surface your spoilboard flat. This is always done and is done with a certain amount of frequency to assure a flat surface for accurate cutting of all projects. This is especially important for what you are attempting. Engraving is especially sensitive to variations in “flatness”.

If you have questions about how to skim your spoilboard, and/or need Bit recommendations etc, there are plenty of folks here that can help!
Michael Tyler

carvebuddy.com

facebook.com/carvebuddy

-CarveWright CNC
-ShopBot Buddy PRSAlpha CNC
User avatar
mtylerfl
Vectric Wizard
 
Posts: 3233
Joined: Thu Jan 29, 2009 3:54 am
Location: Brunswick, GA
Model of CNC Machine: -CarveWright CNC -ShopBot Buddy PRSAlpha

Re: Not an even cut

Postby Leo » Sun Sep 09, 2018 1:10 am

Gunny,

What is your machine? I tried to search 141001, but that is not enough information to find your machine.

Knowing what you have will help us to better understand how to help you.

If it is any sort of a standard CNC Router, we can help you to understand how to "level" your machining platform - spoilboard -

This is imperative to good quality precision work. When you are talking .001, then that is precision.

What make is your machine, so we can look it up.
Imagine the Possibilities of a Creative mind

www.leosworkshop.com
User avatar
Leo
Vectric Wizard
 
Posts: 2683
Joined: Sat Jul 14, 2007 3:02 am
Location: East Freetown, Ma.
Model of CNC Machine: 1300 x 1300 x 254

Re: Not an even cut

Postby mtylerfl » Sun Sep 09, 2018 3:17 am

Hi Leo,

Back in April of this year, Gunny mentioned he has a Piranha CNC
Michael Tyler

carvebuddy.com

facebook.com/carvebuddy

-CarveWright CNC
-ShopBot Buddy PRSAlpha CNC
User avatar
mtylerfl
Vectric Wizard
 
Posts: 3233
Joined: Thu Jan 29, 2009 3:54 am
Location: Brunswick, GA
Model of CNC Machine: -CarveWright CNC -ShopBot Buddy PRSAlpha

Re: Not an even cut

Postby Leo » Sun Sep 09, 2018 12:23 pm

OK, then yes certainly doable for the spoil board.
Imagine the Possibilities of a Creative mind

www.leosworkshop.com
User avatar
Leo
Vectric Wizard
 
Posts: 2683
Joined: Sat Jul 14, 2007 3:02 am
Location: East Freetown, Ma.
Model of CNC Machine: 1300 x 1300 x 254


Return to Hardware related questions

Who is online

Users browsing this forum: No registered users and 3 guests