Model Height

This is the place to post images of work produced using Aspire

Model Height

Postby Aussie » Wed Feb 20, 2019 2:50 am

Hi All,
Just a new user.
When using the design and make models is there a "rule of thumb" for minimum model height ? versus the timber thickness ? if the model height is too low will I lose definition etc. Most of the tutorials seem to use 3/4" material or thicker, what would be the result of using 1/2 or 1/4 material.

Thanks
Ron
Aussie
Vectric Apprentice
 
Posts: 50
Joined: Fri Nov 30, 2018 1:44 am
Model of CNC Machine: Axiom AR6 Pro

Re: Model Height

Postby ZipperHead55 » Wed Feb 20, 2019 4:04 am

That's actually a good question, but I don't think I have a definitive answer for you.

I used to use 3/4" and 5/8" wood when I was starting out (I used to buy cabinet doors from HabitatForHumanity ReStore, that had, you guessed it, 3/4" and 5/8" hardwood panels). Then I started buying rough cut (4/4) lumber and would plane down one surface flat, and usually end up in the .85"-.93" range. One HUGE investment that has paid off for me, particularly since I have been using more and more expensive woods, is a bandsaw with a generous re-saw capacity. I bought the Laguna 14/12 (14" bandsaw with 12" re-saw capacity) which has saved me a lot of money/time/wood. If I have a model that is going to be smallish (under 8" tall), I used to lose a lot of wood because I would remove it from either the top or bottom (with CNC on roughing pass, or sanding the bottom). But once I got the bandsaw, I could cut my wood to suit the size/depth.

All that said, you have to really trust the render/simulation in Aspire. One of the downsides of leaving some wood on the bottom of the model is that Aspire won't cut through the wood if you don't tell it to, so unless you get rid of the scrap wood (in the render) it's hard to judge the finished height of the model. 2 ways to overcome that (if you can't/don't create a profile path) is to use the 2-sided modeling in Aspire, and create a fake pocket cut on the back to remove that extra wood (in the simulation) and the other is to create a fake profile toolpath and cut out the piece with that (you can create ridiculously small virtual-bits that basically laser engrave the piece out (in the simulation) so you can remove the scrap once the toolpaths have been created (by double clicking on the scrap wood in the simulation.

One "trick" that I have learned that is if you have a relatively thin model, and want to give it some heft, is to add on some material on the bottom of the model by increasing the base height in the component properties tab. I wish there was a way to select zones that you want to increase/decrease the height of only that particular zone (imagine dividing a model into layers in thirds, and raise the top a certain amount, keep the middle the same depth, and reduce the bottom). In 3D modeling there is something called "soft selection" that allows for this type of thing.

Anyway, I never answered your question, but explained how to deal with removing extra wood, or add heft to a model. I think a lot of it will come down to what looks/feels right. Sometimes you have to just cut it and see if it looks good, and keep a log of what works for you. Be prepared to make a lot of expensive firewood though ;)
ZipperHead55
 
Posts: 42
Joined: Fri Apr 04, 2014 2:21 am
Location: Edmonton, Alberta, Canada
Model of CNC Machine: Axiom AR4Pro+ and AR8Pro+

Re: Model Height

Postby martin54 » Wed Feb 20, 2019 4:56 am

Not sure I understand you question fully but when you import a model it has a height that is proportional to the length & width, when you resize a model those sizes are kept in proportion. If you then enter the model properties form & just reduce the height of the model then yes you will start to lose detail, the more you reduce the height then the more surface detail you lose, the embossing tool can help as it is designed to try & maintain the surface detail while reducing the overal thickness of a model.
Pictures can help so if there is a particular project you are thinking a couple of screenshots might help, difficult to post files that contain copyright material but screenshots are OK. :lol: :lol:
User avatar
martin54
Vectric Wizard
 
Posts: 4574
Joined: Fri Nov 09, 2012 2:12 pm
Location: Crossgates, Scotland
Model of CNC Machine: Gerber System 48 (modified)

Re: Model Height

Postby Aussie » Wed Feb 20, 2019 4:59 am

Thank you for your reply, even if I posted it into the wrong area.
Winter in Australia is coming and I have made a great deal of firewood :)
I have been importing timber from the USA so mistakes are very expensive.... I usually cut in pine or mdf first as a test.

Over the weekend I will glue two types of 1/4" material and make the model height a little less than 1/4" and see how it goes.

OK understand .... so when using the model height suggested for the material thickness keep close to their recommendations ?
Aussie
Vectric Apprentice
 
Posts: 50
Joined: Fri Nov 30, 2018 1:44 am
Model of CNC Machine: Axiom AR6 Pro

Re: Model Height

Postby martin54 » Wed Feb 20, 2019 1:45 pm

Aussie wrote:Thank you for your reply, even if I posted it into the wrong area.
Winter in Australia is coming and I have made a great deal of firewood :)
I have been importing timber from the USA so mistakes are very expensive.... I usually cut in pine or mdf first as a test.

Over the weekend I will glue two types of 1/4" material and make the model height a little less than 1/4" and see how it goes.

OK understand .... so when using the model height suggested for the material thickness keep close to their recommendations ?


I am still not really understanding what you are trying to do. Why would you want to change the height of a 3D model? If you are trying to keep it as flat as possible but retain as much surface detail as possible then the embossing tool will help with that but for general work leave the model height as it is when he model is scaled to the size you want it.

If you are making a lot of firewood then you are not using the software correctly, the toolpath preview is very accurate so if once you have toolpathed & previewed our job if things don't look right then don't start carving :lol: :lol: With most jobs you shouldn't really need to test.

If you are new to the software & cnc in general then spend some time learning how to use it, the tutorials are very good & also provide tutorial files so you can download & work along with the tutorial rather than just watching. Start at the beginning rather than cherry picking :lol: :lol:

https://support.vectric.com/training-material
User avatar
martin54
Vectric Wizard
 
Posts: 4574
Joined: Fri Nov 09, 2012 2:12 pm
Location: Crossgates, Scotland
Model of CNC Machine: Gerber System 48 (modified)

Re: Model Height

Postby Rcnewcomb » Wed Feb 20, 2019 6:54 pm

When using the design and make models is there a "rule of thumb" for minimum model height ? versus the timber thickness ?

For solid wood it is best to have the carving no deeper than 1/2 the thickness of the material. When material is removed the wood will bow, cup, twist, etc. The effect is amplified if there is a large difference between the moisture content of the wood and the relative humidity in the shop. The effect is less problematic when more of the material remains.

For materials like SignFoam this is less of an issue and you can do deeper carvings.
- Randall Newcomb
User avatar
Rcnewcomb
Vectric Wizard
 
Posts: 3517
Joined: Fri Nov 04, 2005 5:54 am
Location: San Jose, California, USA
Model of CNC Machine: GCnC/WinCNC


Return to Aspire - Gallery

Who is online

Users browsing this forum: No registered users and 12 guests