Fill center of inner closed vector rails

This forum is for general discussion about Aspire
Post Reply
litzluth
Vectric Craftsman
Posts: 250
Joined: Fri May 09, 2014 1:37 pm
Model of CNC Machine: Laguna IQ
Location: Pensacola FL

Fill center of inner closed vector rails

Post by litzluth »

This two rail sweep option can be pretty finicky. Most of us who have used it probably know that if there are overlaps or gaps in the vectors describing the closed rails, the option will be grayed out. But even if it isn't grayed out and indicates it is operational, what I didn't realize until a rather frustrating two hour episode today is in order for the “fill center of inner closed vector rails” to work properly, the vertical/elevation section of the cross section sweep vector must be aligned perfectly in a vertical (or if sitting on its side-horizontal) plane. If it is off just a little, the center section won’t fill.

So snip 1 will fill, snip 2 won't
Attachments
snip1.png
snip2.png

User avatar
ohiolyons
Vectric Wizard
Posts: 1702
Joined: Wed May 27, 2009 7:16 pm
Model of CNC Machine: Laguna IQ
Location: Kettering, Ohio

Re: Fill center of inner closed vector rails

Post by ohiolyons »

post the file, please
John Lyons
CNC in Kettering, Ohio

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: Fill center of inner closed vector rails

Post by SteveNelson46 »

It appears to me that neither one will work. In order to fill the inner vector it has to be a closed vector. Like John said, we could better understand if you posted the file or a link to it.
Attachments
closed vectord.png
Setup.png
Steve

litzluth
Vectric Craftsman
Posts: 250
Joined: Fri May 09, 2014 1:37 pm
Model of CNC Machine: Laguna IQ
Location: Pensacola FL

Re: Fill center of inner closed vector rails

Post by litzluth »

Sorry, I should have been clearer.
I've attached the file. The two closed vectors and the sweep vector are for a new neck heel design for a cutaway guitar I am working on. (It is a little hard to picture here, since the guitar shaft isn't even in the model yet--but you are viewing from the bottom of the heel up toward where the shaft will be). Instead of using the sweep vector in the file, if you substituted one almost identical but did not have the straight portion exactly horizontal, you will see that you can't fill the center of the inner closed vector.

Snip 1 referenced above is the swept profile that worked, snip two (which isn't in the uploaded file) is an example of the type of sweep that won't allow the "fill center of inner closed vector rails" to work correctly.
Attachments
new neck experiment oct 22.crv3d
(826.5 KiB) Downloaded 34 times

User avatar
ohiolyons
Vectric Wizard
Posts: 1702
Joined: Wed May 27, 2009 7:16 pm
Model of CNC Machine: Laguna IQ
Location: Kettering, Ohio

Re: Fill center of inner closed vector rails

Post by ohiolyons »

You couldn't trim a vector so you deleted it, I thought you wanted to know why it wouldn't trim.
The vector to the right (off of your material) what is its purpose? I don't see anyway it relates to the rails.

I'm confused because the fill you want is typically what litzluth has shown filling in between models.
So what area do you want to fill?
The rails and vectors you provided would not need a fill.

Your model is vertical 95 mm, you have a bit that will cut 95 mm (3.74")?
You need to have your profile vectors spaced along the rails, not all in one spot.
John Lyons
CNC in Kettering, Ohio

litzluth
Vectric Craftsman
Posts: 250
Joined: Fri May 09, 2014 1:37 pm
Model of CNC Machine: Laguna IQ
Location: Pensacola FL

Re: Fill center of inner closed vector rails

Post by litzluth »

ohiolyons wrote:
Mon Oct 03, 2022 1:42 am
You couldn't trim a vector so you deleted it, I thought you wanted to know why it wouldn't trim.

When I figured out how to make the "fill center of inner closed vector rails" work by modifying the sweep vector (the one to the right) I just fixed it by making the straight section perfectly aligned on the horizontal, I didn't delete it. I wasn't really asking for help, I was attempting to explain to folks what to do in order to make sure the "fill center" option would work.

The vector to the right (off of your material) what is its purpose? I don't see anyway it relates to the rails.

The vector off to the right is the one used to sweep the two closed vectors to provide the model elevation.

I'm confused because the fill you want is typically what litzluth has shown filling in between models.
So what area do you want to fill?

The fill area is the center of the inner closed vector, which defines the heel.

The rails and vectors you provided would not need a fill.

The model does need a fill inside the inner closed vector, otherwise the heel is a void.

Your model is vertical 95 mm, you have a bit that will cut 95 mm (3.74")?

In order to get the necessary Z height, I have to move the spindle all the way up in the mount, and remove a board in the table. I do have mills that will cut that.

You need to have your profile vectors spaced along the rails, not all in one spot.
I will typically use several different sweep vectors and attach them at different points along the rails. This was just a proof of concept--but I do like the result and it was pretty close to what I was shooting for.

User avatar
ohiolyons
Vectric Wizard
Posts: 1702
Joined: Wed May 27, 2009 7:16 pm
Model of CNC Machine: Laguna IQ
Location: Kettering, Ohio

Re: Fill center of inner closed vector rails

Post by ohiolyons »

I meant to reference Steve's post not yours.

Your component shape could/should be made to lay flat like all the other 2 rail sweeps I have ever seen.
I have never seen a vertical 2 rail sweep as you have created, in fact I'm surprised the software even allows it.
It is no wonder you are having fill issues.

It doesn't matter that you can remove a section of the table if you bit doesn't have a cutting length of 95mm your shaft is going to rub on the wood as it goes down the 95mm.

I'll let people with more 2 rail sweep experience than I to carry on this conversation, but you are using it incorrectly.
John Lyons
CNC in Kettering, Ohio

litzluth
Vectric Craftsman
Posts: 250
Joined: Fri May 09, 2014 1:37 pm
Model of CNC Machine: Laguna IQ
Location: Pensacola FL

Re: Fill center of inner closed vector rails

Post by litzluth »

Ohio-I think you are just having a problem visualizing how this will all fit together.
No other way to do it really. I build/mill guitar necks in 3 phases. The heel area, the shaft, and the headstock. Each is a separate model and separate set up. I think I posted about that long ago. Theoretically it would be possible to do it all at once, but it would be a huge waste of wood (and time--cutting air). Here is an image of how the heel portion would fit into the shaft portion. The heel area is on the right, and is what is modeled in the crv file attached above. The shaft is a separate model.

If you don't fill the center section of the inner rail defining the heel, you get a void that looks like the second image. No good obviously.

My post was simply to alert users that if you want to close that inner section, for some reason the sweep that defines the vertical section of the model has to have a straight section that is exactly centered on the Y or X axis (depending on whether the sweep vector is sitting vertically or horizontally).

Cheers.
Attachments
Screenshot 2022-10-03 112501.png
heel with void.png

User avatar
dealguy11
Vectric Wizard
Posts: 2464
Joined: Tue Sep 22, 2009 9:52 pm
Model of CNC Machine: Anderson Selexx 510
Location: Henryville, PA

Re: Fill center of inner closed vector rails

Post by dealguy11 »

Out of curiosity, is there some reason that piece can't be cut flat (i.e., with the back of it on the table)? Even if you have bits long enough, it seems really sketchy to carve it standing up like that. You could do a different 2-rail sweep to create something very close to that shape, using 2 or 3 profile vectors. Just a thought.

Something like this:
Attachments
Guitar sweep.JPG
guitar sweep.crv3d
(761 KiB) Downloaded 23 times
Steve Godding
Not all who wander (or wonder) are lost

litzluth
Vectric Craftsman
Posts: 250
Joined: Fri May 09, 2014 1:37 pm
Model of CNC Machine: Laguna IQ
Location: Pensacola FL

Re: Fill center of inner closed vector rails

Post by litzluth »

Hi Steve, thanks for the ideas.
Yes, unfortunately, I think it has to be cut standing up (which isn't exactly the easiest set up).
The reason is that the heel is integral to the shaft and the headstock.
I begin with a blank like picture 1. The stack at the end is what becomes the vertical section of the heel that transitions into the shaft.
I mill the heel section first (which has the very end of the shaft contour baked into it), then I use separate models to complete the shaft and the headstock.

Comes out looking like picture 2.

The reason for the material left behind the heel in picture 2 is that is what is used to form the dovetail that joins in the body mortise.
Attachments
1.jpg
2.jpg

litzluth
Vectric Craftsman
Posts: 250
Joined: Fri May 09, 2014 1:37 pm
Model of CNC Machine: Laguna IQ
Location: Pensacola FL

Re: Fill center of inner closed vector rails

Post by litzluth »

Steve, I forgot to mention. You actually helped me with my model for the shaft back in the day--solved the problem of how to get the edges of the shaft rounded just right.

viewtopic.php?f=27&t=24723&p=177138&hil ... ep#p177138

User avatar
dealguy11
Vectric Wizard
Posts: 2464
Joined: Tue Sep 22, 2009 9:52 pm
Model of CNC Machine: Anderson Selexx 510
Location: Henryville, PA

Re: Fill center of inner closed vector rails

Post by dealguy11 »

OK. If I were doing this, I probably wouldn't have bothered trying to fill in the vector rails in the first place. I would have created 2 shapes - the 2-rail sweep for the outside profile and a flat-topped shape using "create shape from profile. One or the other of them would have had their combine mode set to Merge to prevent stray pixels from sticking up above the top of it. I know the 2-rail sweep has the fill function, but combining shapes just seems more natural to me.
Steve Godding
Not all who wander (or wonder) are lost

joeporter
Vectric Wizard
Posts: 519
Joined: Tue Jul 21, 2009 8:22 pm
Model of CNC Machine: ShopBot Buddy Standard
Location: Marietta, GA.

Re: Fill center of inner closed vector rails

Post by joeporter »

https://portal.vectric.com/content/p/MakingaGuitarNeck Would this demonstration from the 2017 UGM be of any help? I believe there are other example also...joe

litzluth
Vectric Craftsman
Posts: 250
Joined: Fri May 09, 2014 1:37 pm
Model of CNC Machine: Laguna IQ
Location: Pensacola FL

Re: Fill center of inner closed vector rails

Post by litzluth »

Hi Joe, thanks for that. Most of what you see (like the Vectric example above) is a neck suited for an electric guitar, and doesn't have the tall heel that an acoustic has. A lot of makers cut the basic acoustic heel shape with a bandsaw, and will then use a rasp or spokeshave, and finally a sanding drum to finish the contours. I just really like the precision and repeatability of doing it with a CNC. It can be a challenge to get it right.

Post Reply