# PCB Circular Ruler

#### ImWolf

Joined May 26, 2013
108
My intention is to modify the compound on my lathe, and I need a circular ruler to set the compound angle at the desired rotation. The ruler will be a flat ring, with 360° graduations and text (numbered) markings. Initially I was searching for something made of either aluminum or stainless steel that was etched with the markings I need. I discovered this was not easy to find, and very pricey to have produced.

Someone on a Machining / Lathe forum suggested that a round PCB might be durable enough to meet my needs, and would be much cheaper to acquire. He said I would need to first produce something called Gerber files to define the design, and then upload the file(s) to https://jlcpcb.com/ for a quote.

I do know that some PCB's are fairly tough stuff, but I'm not sure any I have seen would fare well exposed to hot metal chips falling on them? When I visited the JLCPCB site, the opening page is advertising aluminum boards. Are they actually making PCB's out of aluminum now?

Can anyone here confirm that this JLCPCB company can produce what I need (see image attached), and steer me in the right direction to get started on producing the Gerber file(s) needed to get a quote? Note: this is simply a measuring "ruler" and would not be needed for any sort of electronics.

Thanks,
Wolf

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#### ImWolf

Joined May 26, 2013
108
Yes Eric, I've seen probably hundreds of versions now in my search. Plastic is definitely out of the question with use on a metal cutting lathe. The closest thing I've come across so far is this metal ruler, but the markings are not quite what I want, and the outside diameter would need to be cut smaller.

https://www.ebay.com/itm/164615168778?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

Thanks just the same.... :b
Wolf

#### eetech00

Joined Jun 8, 2013
3,320
My intention is to modify the compound on my lathe, and I need a circular ruler to set the compound angle at the desired rotation. The ruler will be a flat ring, with 360° graduations and text (numbered) markings. Initially I was searching for something made of either aluminum or stainless steel that was etched with the markings I need. I discovered this was not easy to find, and very pricey to have produced.

Someone on a Machining / Lathe forum suggested that a round PCB might be durable enough to meet my needs, and would be much cheaper to acquire. He said I would need to first produce something called Gerber files to define the design, and then upload the file(s) to https://jlcpcb.com/ for a quote.

I do know that some PCB's are fairly tough stuff, but I'm not sure any I have seen would fare well exposed to hot metal chips falling on them? When I visited the JLCPCB site, the opening page is advertising aluminum boards. Are they actually making PCB's out of aluminum now?

Can anyone here confirm that this JLCPCB company can produce what I need (see image attached), and steer me in the right direction to get started on producing the Gerber file(s) needed to get a quote? Note: this is simply a measuring "ruler" and would not be needed for any sort of electronics.

Thanks,
Wolf

View attachment 246209
i don’t see why it couldn’t be made by JLCPCB.

what tolerances do you expect?
Can the ruler be a silkscreened image?
The one issue I see is maybe the thickness. Most PCBs are 1 .7mm. The aluminum round ones are usually used for mounting LEDs. The aluminum acts as a heat sink. They are made of multiple layers with the outside layer made of aluminum.

#### eetech00

Joined Jun 8, 2013
3,320
i don’t see why it couldn’t be made by JLCPCB.

what tolerances do you expect?
Can the ruler be a silkscreened image?
The one issue I see is maybe the thickness. Most PCBs are 1 .7mm. The aluminum round ones are usually used for mounting LEDs. The aluminum acts as a heat sink. They are made of multiple layers with the outside layer made of aluminum.
I would send an image to JLCPCB and ask if it could be made if you supplied the gerber files.

In fact I might design this just to see if I can.

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#### Ian0

Joined Aug 7, 2020
5,924
Are they actually making PCB's out of aluminum now?
Yes - they are 1.6mm thick aluminium, with a thin insulating layer on top, then copper tracks on top of that. They can print whatever you want on top of that, provided you can output it in gerber format.
EIther you will have to draw your ruler on a pcb package or draw it on a 2D cad program that can output Gerber (and that's a bit of a rarity). I used to have software on my iBook that could do convert dxf to gerber, but have forgotten what it was called.
(I'll get it out of the cupboard where it has gone to retire and switch it on, if you need to know)

#### ImWolf

Joined May 26, 2013
108
i don’t see why it couldn’t be made by JLCPCB.
When I previously went to the JLCPCB page there were options for board thickness, including .80mm, but I'm new to all this.

As long as the markings are very durable and can withstand many years of brushing and wiping clean then I guess silkscreen would be alright... not really sure what my options are.

The graduations should be as accurate as possible for positioning the angle. The outer and inner diameters can be 1/32" either way and I"ll machine the mating part to match.

#### Ian0

Joined Aug 7, 2020
5,924
When I previously went to the JLCPCB page there were options for board thickness, including .80mm, but I'm new to all this.

As long as the markings are very durable and can withstand many years of brushing and wiping clean then I guess silkscreen would be alright... not really sure what my options are.

The graduations should be as accurate as possible for positioning the angle. The outer and inner diameters can be 1/32" either way and I"ll machine the mating part to match.
You could have the text in copper and it would probably be more durable than silkscreen, but less easy to read.

#### ImWolf

Joined May 26, 2013
108
EIther you will have to draw your ruler on a pcb package or draw it on a 2D cad program that can output Gerber
The image I originally posted here was created in AutoCad 13 which is older than Gerber. It can output to DXF format, but then AutoCad is the only software I have that will open the DXF file.

#### ImWolf

Joined May 26, 2013
108
Ideally, I would like something that has the appearance of metal, with black graduation lines and numerical markings.

Due to design constraints, the finished piece would also need to be no thicker than 1mm.

Wolf

#### Ian0

Joined Aug 7, 2020
5,924
The image I originally posted here was created in AutoCad 13 which is older than Gerber. It can output to DXF format, but then AutoCad is the only software I have that will open the DXF file.
I didn't think anything was older than gerber. I remember my days as a student at Marconi sending off gerber data on punched paper tape!

#### Ian0

Joined Aug 7, 2020
5,924
I remember the name of the software - it was called CENON.
https://www.cenon.info/
I haven't seen any others that can output Gerber. It was really handy when I wanted a pcb printed with some graphics.

#### ImWolf

Joined May 26, 2013
108
I didn't think anything was older than gerber. I remember my days as a student at Marconi sending off gerber data on punched paper tape!
That statement explains just how much of a dummy I am at this..... because I never heard of Gerber files till a few days ago! ;b

Wolf

#### Ian0

Joined Aug 7, 2020
5,924
That statement explains just how much of a dummy I am at this..... because I never heard of Gerber files till a few days ago! ;b

Wolf
It's quite a simple format, all in text.
https://en.wikipedia.org/wiki/Gerber_format
It wouldn't be impossible to write it by hand to produce a circular ruler. Most of it is just the beginning and end positions of a line.

#### ImWolf

Joined May 26, 2013
108
I remember the name of the software - it was called CENON.
https://www.cenon.info/
I haven't seen any others that can output Gerber. It was really handy when I wanted a pcb printed with some graphics.
Soooooo...... where's the free version of Cenon to play with? :b

Wolf

#### eetech00

Joined Jun 8, 2013
3,320
My intention is to modify the compound on my lathe, and I need a circular ruler to set the compound angle at the desired rotation. The ruler will be a flat ring, with 360° graduations and text (numbered) markings. Initially I was searching for something made of either aluminum or stainless steel that was etched with the markings I need. I discovered this was not easy to find, and very pricey to have produced.

Someone on a Machining / Lathe forum suggested that a round PCB might be durable enough to meet my needs, and would be much cheaper to acquire. He said I would need to first produce something called Gerber files to define the design, and then upload the file(s) to https://jlcpcb.com/ for a quote.

I do know that some PCB's are fairly tough stuff, but I'm not sure any I have seen would fare well exposed to hot metal chips falling on them? When I visited the JLCPCB site, the opening page is advertising aluminum boards. Are they actually making PCB's out of aluminum now?

Can anyone here confirm that this JLCPCB company can produce what I need (see image attached), and steer me in the right direction to get started on producing the Gerber file(s) needed to get a quote? Note: this is simply a measuring "ruler" and would not be needed for any sort of electronics.

Thanks,
Wolf

View attachment 246209
What tool did you use to make this drawing?

If it can output a .dxf file, please post the file.

#### metermannd

Joined Oct 25, 2020
328
What I would do is before zipping up the gerbers to send off, to copy the silkscreen layer to the copper layer.
That way the lettering is that much more durable.

I'd also put a couple alignment targets in the drawing (if they can be placed outside the PCB area itself).

Before committing to JLCPCB, check around with PCB Shopper to check pricing etc. JLCPCB is pretty quick about staging orders into the production queue once you've paid, and the order becomes nonrefundable at that point (other than shipping costs).

#### eetech00

Joined Jun 8, 2013
3,320
Ideally, I would like something that has the appearance of metal, with black graduation lines and numerical markings.

Due to design constraints, the finished piece would also need to be no thicker than 1mm.

Wolf
Hi

Well...here's a first pass attempt.
I designed the initial layout in AutoCADLT, then imported a .dxf file from AutocadLT to Designspark PCB.
The colors, text size, and board thickness are adjustable of course.

Below is a DesignSpark 3D view.

Below is a 2D layout view from DesignSpark PCB

Tomorrow I'll generate some gerber files and see what I get....

#### Ian0

Joined Aug 7, 2020
5,924
I use allpcb, and they offer aluminium boards in 0.8mm and 1mm. They would make you 5 (minimum order) for US$12* (plus quite a lot of shipping) https://allpcb.com/online_pcb_quote_new.html *total, not each. [EDIT] they do aluminium substrate boards up to 2mm - I'm thinking about fascia panels. . . . . A 2U 19" rack fascia panel for US$4.60 each, and a minimum order of 5 - that would put a lot of fascia panel companies out of business.

#### Ya’akov

Joined Jan 27, 2019
6,286
I haven't used this service, and I have no idea what the cost would be—except they say "from \$50 for one". But hey can do laser cutting of metals with engraving. You may have looked at them already, but just in case:

https://www.ponoko.com/laser-cutting/metal