Help with Vector Texture

This forum is for general discussion about Aspire
thetinman101
Posts: 4
Joined: Mon Dec 18, 2017 12:49 am
Model of CNC Machine: XCarve 750mm

Help with Vector Texture

Post by thetinman101 »

Good day all. I am trying to make a cutting board using Aspire 9.0 and the "Create Vector Texture" button. When I build the model (15" x 7"), Angle = 0.0, Line Spacing = 0.75", Amplitude = 0.6" and Wavelength = 3.25", the pattern looks right on the screen. I create my gcode using Quick Engrave and a 0.125" End mill, save the gcode and then I send it out to the CNC, where I use PicSender as my software of choice. I will cutt 2 different woods (walnut and maple, for example). Now the problem becomes apparent in that the pieces will not fit together properly. There is spacing between each piece and the curves are not smooth and flowing. I have included a photo to better show what I am trying to describe. I have the same problem whether I alternate the pieces or keep the together in the order they came off the machine.
Any thoughts as to why this is happening and/or how to fix it? Is this a case of using the wrong design tool?
Thanks in advance for the help
Regards
Tim
Attachments
Pieces clamped together
Pieces clamped together

pedro905
Posts: 4
Joined: Sat May 19, 2018 5:50 pm
Model of CNC Machine: Shopbot

Re: Help with Vector Texture

Post by pedro905 »

Can you post a screen shot?
PeteM

User avatar
ChrisInEstes
Vectric Wizard
Posts: 841
Joined: Fri Jul 17, 2009 8:00 pm
Model of CNC Machine: Vytek 4' X 8' - Perske Spindle - Mach3
Location: Estes Park, Colorado, USA

Re: Help with Vector Texture

Post by ChrisInEstes »

If I had that issue...

I'd first turn it over while clamped to see if the gaps are the same, and in the same place on the bottom.

I'd also flip the walnut pieces in both axes to see if they fit better.

If the gaps are the same top & bottom, and it did no good to flip the walnut pieces in both axes, I'd figure it was a climb milling/conventional milling issue due to machine/tool flexing.

Chris
Aspire 9.5 - FlexiEXPERT 11 - Vytek Rebel 4' x 8' - 5HP Perske Spindle

User avatar
martin54
Vectric Archimage
Posts: 7339
Joined: Fri Nov 09, 2012 2:12 pm
Model of CNC Machine: Gerber 48, Triac PC, Isel fixed gantry
Location: Kirkcaldy, Scotland

Re: Help with Vector Texture

Post by martin54 »

Could be a number of things, flex in machine, bit deflection are a couple, you could try cutting in the other direction as Chris suggests, what speed feed & DOC settings are you using, slowing things down &/or taking a shallower DOC might help, not the most rigid of machines you have & these really need to be a very good fit, just one other thing I have read somewhere, you need to be careful using walnut for chopping boards because of the oils that can leach out, not sure where I read it to be honest as it was quite a while ago when I was looking at making a couple of chopping boards :lol: :lol:

User avatar
gkas
Vectric Wizard
Posts: 1450
Joined: Sun Jan 01, 2017 3:39 am
Model of CNC Machine: Aspire, Axiom AR8 Pro+, Axiom 4.2W Laser
Location: Southern California

Re: Help with Vector Texture

Post by gkas »

Sorry to say, but I doubt that you will ever get an Xcarve to cut that correctly. My first machine was an Xcarve. After a year of problems, I gave it away. There is so much flex, that cuts are not easily repeatable. I had mine considerably beefed up, yet I had to make VERY shallow cuts at a slow feed to get reliable cuts.

I once made three lids for a Paradise Box for the same project. The front and rear of the lid are beveled. Because of the Vcarving around the lid perimeter, it is very easy for the eye to notice if the bevel is not perfectly straight. I could not get the Xcarve to cut the bevels flat and straight. I finally picked a piece of wood with very straight grain. Combined with a very shallow DOC passes, I completed the cuts. I could have easily completed the bevel cuts on my router table or hand plane. I really wanted to get the Xcarve to make the cuts. I did, but never reliably.

The solution is a very shallow DOC with a sharp bit. The biggest problem with this solution is that the inherent flex in the machine will cause a poor edge quality from lots of passes. Lots of sanding.

User avatar
adze_cnc
Vectric Wizard
Posts: 4324
Joined: Sat Jul 27, 2013 10:08 pm
Model of CNC Machine: AXYZ 4008
Location: Vancouver, BC, Canada

Re: Help with Vector Texture

Post by adze_cnc »

Pre-question: why use Quick Engrave toolpath? Why not use profile "on the line" instead?
gkas wrote:Sorry to say, but I doubt that you will ever get an Xcarve to cut that correctly.
You are partially correct but not because of flex in the machine. No machine will ever cut this project properly, as it stands, even if flex was wholly eliminated.

The problem is cutting these vectors on the line thus changing the curves' geometry making them not mate with each other. The only way this would work is if the bit had zero width. The attached image shows vectors created as "tinman" has cut them demonstrating that they don't mate.

You need to cut the walnut pieces on one side of the line and the maple pieces on the other side of the line so that the resulting pieces mate. You will loose every second piece doing that, though.
offset cut.png

User avatar
SteveNelson46
Vectric Wizard
Posts: 2282
Joined: Wed Jan 04, 2012 2:43 pm
Model of CNC Machine: Camaster Stinger 1
Location: Tucson, Az.

Re: Help with Vector Texture

Post by SteveNelson46 »

I think that just cutting the parts individually instead of having a common border will work also. Of course, it will also depend on the accuracy of your machine.
Steve

User avatar
adze_cnc
Vectric Wizard
Posts: 4324
Joined: Sat Jul 27, 2013 10:08 pm
Model of CNC Machine: AXYZ 4008
Location: Vancouver, BC, Canada

Re: Help with Vector Texture

Post by adze_cnc »

Steve:

That's what I was getting at. That is unless the pieces are cut to their exact size they won't nest together at all. Unfortunately I took a convoluted way of getting there.

Steven

User avatar
TReischl
Vectric Wizard
Posts: 4575
Joined: Thu Jan 18, 2007 6:04 pm
Model of CNC Machine: 8020 48X36X7 RP 2022 UCCNC Screenset
Location: Leland NC

Re: Help with Vector Texture

Post by TReischl »

martin54 wrote:.....just one other thing I have read somewhere, you need to be careful using walnut for chopping boards because of the oils that can leach out, not sure where I read it to be honest as it was quite a while ago when I was looking at making a couple of chopping boards :lol: :lol:
Ummm, not quite right there Martin. They sell walnut oil by the bottle in grocery stores for I guess cooking. And just think, we eat walnuts, right out of the shell, no processing! And. . . .

"It is a good source of omega – 3 fatty acids, which are essential fatty acids. So the body needs to get them from diet. Walnut oil has a nutty flavor and a light aroma. ... This oil has immense nutritional value and is safe to be taken in diet."

Sounds to me like a peanut farmer was puffing some smoke up your kilt! :lol:
"If you see a good fight, get in it." Dr. Vernon Johns

User avatar
TReischl
Vectric Wizard
Posts: 4575
Joined: Thu Jan 18, 2007 6:04 pm
Model of CNC Machine: 8020 48X36X7 RP 2022 UCCNC Screenset
Location: Leland NC

Re: Help with Vector Texture

Post by TReischl »

To amplify on what Adze was saying above:

It is not possible to run a cutter down a centerline and then have the edges match up. The only time this works is when the cut line is a straight line. It does not work with curves. To understand what is happening:
1.JPG
This was created by offsetting a bezier line .25 in both directions.
2.JPG
The above shows that the curved lines are precisely .5 apart.
3.JPG
The above shows the two halves brought together, notice they do not fit.
4.JPG
This is a closeup of the left end that illustrates the issue. The lines were precisely .5 apart, but that is across the diameter of the tool.

So, the only way to cut edges that match up perfectly is to cut them individually using the same line on both pieces. Centerline cutting does not work on curves or angular pieces. Probably the easiest way to visualize this issue is:
5.JPG
"If you see a good fight, get in it." Dr. Vernon Johns

User avatar
dealguy11
Vectric Wizard
Posts: 2462
Joined: Tue Sep 22, 2009 9:52 pm
Model of CNC Machine: Anderson Selexx 510
Location: Henryville, PA

Re: Help with Vector Texture

Post by dealguy11 »

So to be very specific for the original poster who may or may not be following all this, you need to cut each of the slices using a profile toolpath cutting outside the line, not on the line. If you do that, you should be able to use the same vectors for each slice.
Steve Godding
Not all who wander (or wonder) are lost

Samson
Vectric Wizard
Posts: 322
Joined: Fri May 02, 2014 10:14 pm
Model of CNC Machine: 4x4

Re: Help with Vector Texture

Post by Samson »

TReischl wrote:
martin54 wrote:.....just one other thing I have read somewhere, you need to be careful using walnut for chopping boards because of the oils that can leach out, not sure where I read it to be honest as it was quite a while ago when I was looking at making a couple of chopping boards :lol: :lol:
Ummm, not quite right there Martin. They sell walnut oil by the bottle in grocery stores for I guess cooking. And just think, we eat walnuts, right out of the shell, no processing! And. . . .

"It is a good source of omega – 3 fatty acids, which are essential fatty acids. So the body needs to get them from diet. Walnut oil has a nutty flavor and a light aroma. ... This oil has immense nutritional value and is safe to be taken in diet."

Sounds to me like a peanut farmer was puffing some smoke up your kilt! :lol:
Actually, nut oils are the same as vegetable oils, in that they go rancid and become toxic.
The only safe oil, is mineral oil. It doesn't go rancid or react with foods.
Using butcher block oil, is, well... mineral oil.

User avatar
SteveNelson46
Vectric Wizard
Posts: 2282
Joined: Wed Jan 04, 2012 2:43 pm
Model of CNC Machine: Camaster Stinger 1
Location: Tucson, Az.

Re: Help with Vector Texture

Post by SteveNelson46 »

TReischl wrote:
martin54 wrote:.....just one other thing I have read somewhere, you need to be careful using walnut for chopping boards because of the oils that can leach out, not sure where I read it to be honest as it was quite a while ago when I was looking at making a couple of chopping boards :lol: :lol:
Ummm, not quite right there Martin. They sell walnut oil by the bottle in grocery stores for I guess cooking. And just think, we eat walnuts, right out of the shell, no processing! And. . . .

"It is a good source of omega – 3 fatty acids, which are essential fatty acids. So the body needs to get them from diet. Walnut oil has a nutty flavor and a light aroma. ... This oil has immense nutritional value and is safe to be taken in diet."

Sounds to me like a peanut farmer was puffing some smoke up your kilt! :lol:
I think that the toxicity stories come from the discarding of the hulls. This is from Google:

Black walnut trees have large concentrations of juglone and hydrojuglone (converted to juglone by some plants), which is toxic to many plants. Juglone concentrations are highest in walnut buds, nut hulls and roots but are also found in lesser quantity in leaves and stems.
Steve

thetinman101
Posts: 4
Joined: Mon Dec 18, 2017 12:49 am
Model of CNC Machine: XCarve 750mm

Re: Help with Vector Texture

Post by thetinman101 »

To start off, Thank you everyone for all your pointers and suggestions. I have been followoing all the answers here since I posted, and am amazed at all the people that stepped up to offer good ppositive critiques and thoughts.
To answer adze_cnc first, I used Quick Engrave because I couldn't get Profile to work without adding in a boarder (ie. making the entire project a single vector) I cut a set of 7 waves in the walnut then took this single piece over to the radial arm saw and then cut off the boarders (see attaced photo). We also used a laser to cut this same pattern out on paper and as you ppointed out, on a zero width cut (.05 mm or something llike that, so for our discussion here, it really is equal to a zero waste cut) and the pieces fit together.

I watched a youtube video of a guy making a single wave pattern, and it seemed that he had the same problem and he was using a router and a router table, so that removes the flex issue. His solution was to actually use 2 different bits with bearings. Used one bearing set for the top edge of the wood and the other bearing set for the bottom edge. He would have to do this with each piece. Seems that it the only way this will work properly.

My thought here is that I will finish this project off by hand sanding each piece to fit (ughhhhhh!!!) and not attempt this project again on the CNC but rather band saw, hand router and pattern guides.

As to the final finish I planned on using - bees wax and mineral oil mix. Makes a nice finish, won't go rancid and is food safe. Getting food poisioning from a project would really not assist in making a customer base for future projects. LOL
Attachments
IMG_20181110_121436.jpg

User avatar
adze_cnc
Vectric Wizard
Posts: 4324
Joined: Sat Jul 27, 2013 10:08 pm
Model of CNC Machine: AXYZ 4008
Location: Vancouver, BC, Canada

Re: Help with Vector Texture

Post by adze_cnc »

thetinman101 wrote:...not attempt this project again on the CNC but rather band saw, hand router and pattern guides.
This, I believe, is a case of "cutting off your nose to spite your face". This project is wholly possible using a CNC router and to an equal fidelity as the manual bandsaw and template routing method. It's just not doable the way you originally set out to do it without, as you observed, a great deal of sanding.

If I feel up to it later I'll craft a file to demonstrate this.

Steven



---
border not boarder; rabbet (or rebate) not rabbit; their, there, they're, your, you're have distinct uses that should be learned by all elementary school children

Post Reply