Sketchup to CNC - Advice

Hi Guys,

I was hoping for a bit of advice or help…I have looked around forums and google but can’t quite find clear answers, however that might just be.

I will try to keep this simple, our business is looking to invest in a fairly standard CNC for wooden carvings. I’ve been using sketchup for a number of years and although I’m still no pro I feel I can use it for good enough for what we need for work.

What I use this for is to design parts for machines we have here or for new product prototypes, this are then printed using our 3D printer…now I feel I’ve got this down to a tee, I really don’t come across many problems with this and everything comes out the way I plan.

My MD has seen potential in me I guess and like I said wants to invest in a CNC machine for plastic and wooden carvings for our business.

With our 3D printer I know the limitations of size it will print so design my models around that, I can see these sizes on CNC machines but not with the height or how deep they will carve…am I missing something?

My main target here is to find a machine that I can use alongside sketchup, design whatever I want produce on sketchup (or another program if I have to), convert and then send to CNC to carve…I’m appreciate there will be more to it than this but that’s the jist.

I’m struggling to find the info on where the limitations for size are when looking for a machine when it comes to height.

I’d be grateful if someone here could just throw me some pointers of what the main things are I should be looking for with what we want it to do.

Thanks in advance

We, the University I work for, bought a Shark HD4 a few years ago. I honestly don’t use SU with it as I don’t need to. It came with VCarve Desktop software that is pretty easy to use. It can bring it lots of vector and some raster files which it can convert to vector. It has a 25"x25"x4" (I think on the Z) work area. It is open on each end so longer pieces can be feed through it if needed. We’ve made signs around campus from recycled wood from trees cut on campus and reclaimed wood from broken furniture. We opened a remote campus from an old tobacco warehouse and used the original floor boards as give-a-ways at the grand opening.
This unit is pretty well built and was about $5k USD so not cheap. We go through bits quickly depending on if we use hard wood for projects. It looks like they have the HD520 now and has a travel area XYZ of 25’’ x 50’’ x 7’’ so not bad at all for $5k. It can also take a 4th axis add-on if you want to go that route.
https://www.nextwaveautomation.com/shop/SHARK-HD520®-p200906196

Hi Sean,

Thanks for your input, I’ve only just had a chance to read it but I will take a look into the Shark machines…we haven’t discussed a budget yet so I’m not really sure what my MD is thinking.

One question though…I’m assuming the Z travel of 4, 5 or 7 inches is the max depth of the cut aswell…ie, if we were to made a 3D car for example, then the max hieght of the car would be whatever the Z travel was…within reason ?

Thanks again

Yes, your max Z travel is as tall as you can use. Such is the limit of consumer CNC machines :wink:

I had though so but didnt want to buy a 5K machine and realise there was some random rule i hadn’t checked

Thanks

As far as using SketchUp with a CNC, at the end of the day all you’re doing is putting G Code into the CNC machine to make it cut stuff. You can create G Code with a bunch of different CAM programs, many for different purposes. Not only do I use a bunch of different CAM programs, I make one as well so happy to field any questions there.

As far as what machine you should choose, for carvings you’re likely going to find a lot of machines that can cut up to 6-8" in the Z axis. There are taller ones if you want, but likely if you’re doing carvings you won’t need to go too much higher than that.

I’ve seem some people get a rotating 4th axis for their machines and take out the table in the middle so they can mount whole logs and carve things like statues and the like…

As far as what machine to get that answer really depends on what you want to cut, and how fast you want to cut it. In the lighter duty end you could look at something like an Inventables X Carve. If you’re looking at something larger (and more heavy duty) I’d look at ShopBot, Camaster, and Avid CNC. They make a variety of sizes and prices. Both SB and Avid make machines that ship flat and can be assembled in your space, good if you can’t get access to a commercial space and a forklift…

Hope that’s a good start. Let me know if you have any other quesitons…

1 Like

Thanks Eric,

I plan to use sketchup as it’s free and i’m firmilar with it, i have used Solidworks in the past but unless things change i doubt we’ll be getting that…its a great program but for what we want the machine to do it’s overkill at the moment.

The width and length/depth is easy to work out in respect to getting the biggest as to where the mchine will go or fit in the workshop, I’m just making sure that the height is something we dont want to regret later on so want to make sure we get that right. I’ve seen some cheaper machines but in the spec’s they weren’t saying what the height or Z axis is capible of.

Another question i have (bare with me if this sounds daft but this is new to me) and that is…I’ve seen on some youtube vid’s where machines make 2 cut’s, the first being really rough to get the shape of the model and then the 2nd cut to give it the really fine detail…is this 2 seperate drawings/jobs sent to the machine or when designing the model do you program it as one job?

I will take a look at those machine you recommend, thanks again

You can send those jobs different ways… Some machines have tool changers, some do not. On machines that don’t it’s typically two files, although some machines have the ability to prompt the operator to change the tool. On a tool changer machine, the tool changer does it automatically.

If you’re doing a carving with multiple toolpath types, but the same bit you can send one file over and let it run. Does that make sense?

Also, in regards to the Z it’s most likely that any commercial router is going to have what you need. If you’re carving wood you likely won’t put anything on the table that’s over 3" tall, and most of these machines have 5-6" Z axes. Remember most bits are only 2-3" long at most anyway.

Where you can run unto trouble is if you’re cutting out bit billets of foam, those can come in really thick. For that some of these machine makers will make you an extra tall Z. You sacrifice rigidity, but for cutting in foam that doesn’t matter. You also would need to get extra long bits to reach that deep.

1 Like

It does make sense, we have a vinyl printer here and although thats a different machine altogether the operation sounds similar…I design a label or whatever which contains multiple background and forground colours and the machine or pc will tell you when each colour needs changing but I am aware that high-end will do this this for you…

My MD can get a bit crazy sometimes and forget limitations, some of the things he’s asked me to do on our 3D printer is unreal

Looking around I think 3" would be fine for what we would want it for, I quite like the look of the Stinger 1 from Camaster…

With VCarve it’s all done in one drawing with different paths with different tools. Again this comes with the Shark CNC machine :wink:

I’ve just done a brief search about Vcarve and found some tutorials/videos…i will watch these before making any rash decisions.

I’m from the UK so i need to make sure i dont get caught out with USA/UK differences as well

1 Like

It’s not free for commercial use. I’m affraid you would need the PRO-version for that…

Thanks, Tweenulzeven…i will bare that in mind

I need to make time and see if Easel will work with our Shark CNC. It looks very easy but it might only work with their X-Carve CNC.

Coming into this almost a year later so not sure how things panned out but, for what it’s worth…
I have both a Piranha FX and now Piranha XL. The FX has a 12" x 12" “capacity” and the XL has a 12" x 24" capacity. The backs of each are open ended so no reason a longer board can’t be placed on the bed.
I recently decided to convert some old scaffolding to mobile workstations, one specifically for small drillpresses to set each up for a very specific task. To reduced shop space I wanted to mount as many as four on a single shelf. To get them all on one board, including space for turning the handle, the board needed to be 36" wide x 11" deep. I also wanted the board to have slots for commonly used spare drill bits, allen wrenches, pencils, measuring tools, Star bits and more. In the end this is what the board looked like. Since I am very comfortable in SketchUp but have no idea or desire to how to lay out such a complicated piece in Vcarve. So… I draw everything in SketchUp and then import that file into Vcarve. Since this board was 36" deep and the XL capacity is 24" I make two copies of the 24" board, make each of those “unique”, paint them a goofy color to remind me they are unique and then cut each of them in half to 18" long. The lower I call “Lower” the upper “Upper”. To prepare for import in Vcarve I “Hide” everything in the SketchUp model


except just the “Lower” then save the file. I jump over to V-Carve, import the .skp file which only includes the “Lower” 18" section. In Vcarve I set the tool paths, save those paths as a .tap and save the actual Vcarve file. I then jump back to SketchUp, unhide the Upper 18", hide anything else, save the file and repeat the process above for Vcarve. When at the CNC I place the 36" board on the bed, align, lock down and then run “Lower.tap”. When done I slide the 36" board 18" forward, lock down and then run “Upper.tap”.
Sounds crazy but works very well. Used to run four 12" .taps on the FX to create 48" boards!

For reference to the actual application of this CNC project here is the 36" Board and everything I wanted to get on it. No way I could touch this level of detail by laying it out in Vcarve. The color coding in SketchUp also helps me set my toolpaths (yellow is a Tabbed full through, blue is .45 depth, red is full thru etc). The second photo shows abbreviated versions of the drill presses with the dimple of the bit as primary focus and then a line down from each to show where that point will hit the board at each adjusted level of the drillpress table.


That’s an excellent design!

I was wondering, can you post that file (or send it to me directly) I’d love to run it through www.getfabber.com to see how it works.

Eric,
Will email live .skp file to you directly since it is still a work-in-progress and I am considering doing an Instructable and/or Udemy course on “Building a Mobile Workstation” using this design. Attached to this forum post is a screenshot of latest version.

FYI: I was on an RV trip when I drew this so no access to the CNC machine. When I returned home I realized the series of “Stops”, the 1/4" peg holes and the square “Dogs” (showing on earlier post) would not be that functional down at the same level the drill press base was attached to so I am in the process of transferring those holes to another board that will actually get mounted to the drillpress table so it is then also adjustable up/down with the table. Not done with that yet. Attached contains part of the old and some of the new. I also added two goofy shaped slots for mounting a 10" Rikon bandsaw to the same shelf on the scaffold.
Again I “Group” all of my CNC 2Ds under a Scene called “CNC” (imagine that :-)) then just before I plan to import the .skp into Vcarve I Hide all of Components in that Group then do a Save As. Because I am limited to the 12" width (no limits to length BTW) of my Piranha FX or XL I can only run one board or section of a board at a time so I Vcarve one board/one section at a time as well.
For what it’s worth the drillpress holes are calibrated for a Wen 8" DrillPress and work on a Steele 8" and, I believe, a Menards Tool Shop brand 8". Yesterday I purchased a Rikon 8" to test that alignment as well and will eventually calibrate for other brands of 8" thus the 3 “slots” vs holes. Although I own several larger, high-end drill presses (which are planned for mounting on this same yellow scaffold) I set up the small, 8", inexpensive presses for very specific tasks to attach my recently patented threaded tenons (https://ThreadedTenonJoinery.com)
Again, have at it and feel free to message me directly if I can be of any assistance otherwise.
Mike