Hints for doing jobs bigger than table?

[John H]

A mate of mine wants some stuff CNC'd into his wooden tailgate for his ute.

As my table is only small, it will need to be done in three lots of machining, moving the area to be machined onto the table with each go.

The job is two lines of writing and I'll be using VCarve Pro to generate the G-Code

I've never done this before so I'm after some hints on the best way of doing it. i.e. aligning and setting up each machining operation so I don't screw up the spacing in the words.:oo:

[John H]

Here is a preview of the Job

[namtrak]

Looks great, what a lucky bloke to be getting such a cool tailgate!! I bet his ute looks a million dollars!!

[John H]

Heh :D ...as long as I don't screw up the tailgate :doh:

[Greolt]

John I take it the lettering is larger than your table.

Just lay out the job in Vcarve with the origin in the centre, then break the lettering into two pieces. Make a toolpath for each section.

Mark the origin (0,0) on the job. In the centre.

First setup has the origin at one end of the table. Set the X and Y zero on the mark. Cut the first toolpath.

Move the job so that the origin is now at the other end of the table. Set the X and Y zero again on the mark. Cut the second toolpath.

I have saved a Vcaeve file at this link. This forum has very (ridiculous) small file upload limits.

http://web.aanet.com.au/greolt/Floorsanding.crv

Hope that makes sense. :)

Greg

[John H]

Hi Greg,

Thanks for the reply. That makes perfect sense.

But, I need to do this job in three operations as the text is about three times longer than my table. So I don't think this method will work here.

I have filed away your method for any jobs that can be done in two table lengths though :)

[Greolt]

Well it is only a little more difficult to do but much much harder to explain in a few paragraphs.

Set up your material in Vcarve and see that you can specify where the origin is.

Still need to break the job up into pieces that you can cut. Convert text to curves to do this

Edit material size and change the origin point for each separate piece/toolpath. You will need to re centre the vectors each time because the material will move and leave them behind.

Choose origin points that you can easily and accurately mark out on the tailgate.

Common sense will have to fill in the gaps in my explanation. It is not hard. You will figure it out. :)

Greg

[rodm]

Hi John,
Greg has covered it well. Only thing I will add is clamp a sraight edge on your table so you can slide the baord along and keep your Y axis reference. This will keep your lettering on the same hoirzontal line. You then only need to find the new X stating point at the next break in the lettering.

Another method would be to mark your straight edge the same distance that your break is in the drawing. You could do rectangles in your drawing but not include them in the cutting path. It would require three drawings and you could copy parts two and three to drawing two and then just copy part three to drawing three. With this and the straight edge your 0,0 reference will be the same for all three cuts. If necessary go more than three parts if helps space the gap between letters. You do not want to have a break point in the middle of a letter.

Support the overhang otherwise it might tilt and cause a variation in cutting depth or worse topple your machine.

[John H]

Thanks Guys, got it worked out now.

[rodm]

Photos are mandatory :D

[John H]

All done :D

I had one small problem when a set screw came loose (stupid me forgot the loctite) :doh: This screwed up the inside of the letter "d" (sorry Mick) but some filler or expoy should mask it fairly well.

Once I got my head around how to do it, it was fairly easy. I did it in three cuts with a little tweaking on the letter spacing.

Great learning experience.

[rodm]

Nicely done John.

Easy to colour in if you want as well. Use acrylic paint and just splash it in the lettering and don't worry about any that gets on the face. Concentrate on getting a good depth of colour in the lettering. Once dry hit the surface with an orbital and you end up with nice sharp paint edges. You will have to refinish the timber afterwards.

[namtrak]

Thanks John and co.

Final product - only a dodgy phone camera, but you get the idea.

[rodm]

Looks great, what a lucky bloke to be getting such a cool tailgate!! I bet his ute looks a million dollars!!

Does now :2tsup:

[John H]

Stands out really well :)

[namtrak]

Got my first job from the tailgate today, guy pulled my up on and asked if I did floorsanding!!!

50sqm of Parquetry!!

Thanks John

[John H]

Cool :)