I had a lovely weekend in London a couple of months ago, staying in a rather nice hotel. The said hotel had wooden keycards to get into the rooms, nicely engraved with the hotel name. Which got me thinking – could I make one of my own? I started researching possibilities, learning about NFC tags and working out the practicalities of making a ‘digital’ wooden business card. Here’s the result, and below, I focus on the process.
What’s NFC?
Near Field Communication is a short-range wireless technology that enables two devices to communicate when they are brought within close proximity, typically a few centimetres of each other. It’s what powers contactless payments and wireless pairing without Bluetooth. And what powers the chip? Well, that’s the reader – get it close enough and it will induce a current in the tag, powering it up enough to transfer the data.
What’s an NFC tag?
That’s the antenna and chip in a format that makes it easy to use. I experimented with both a sticker variety and a plastic disc type. Each had a different amount of memory, the sticker having just enough for some text and the disc perhaps enough to hold enough information for a tiny image. The tags can be written to by an enabled phone (most up-to-date phones) via an app:
Choosing what to share
Upon doing my research, I found there was the potential for lots of different information that could be included on a tag. This is dependent on chip memory size and eventual use. I decided that I would set up a contact card (vCard format) that I would host on my website and have my card point to that. On scanning the card (or the QR code, more on that later), the phone will access the file, and then throw up the opportunity to save the downloaded details for The Studio to the Contacts app. This allows me to update the contact details without needing to update the tag or the QR code, so the cards would never be out of date. Just putting the URL address for the file keeps it small, but does require the reading phone to be connected to the internet to access the data.
Practical notes for WordPress set up:
- WordPress-hosted sites need to edit their functions.php file to allow uploads of vCard-formatted files (.vcf) as they are otherwise blocked. This code can be removed or commented out after the upload is completed.
- For a shorter or customised URL, it is necessary to set up a redirect plugin, as the file URL cannot be directly changed. For example, I set mine up to redirect via https://perfectly4med.co.uk/TheStudio.vcf and popped this address onto the tag
Intended use
My plan is to carry the card as a means to quickly share my digital contact details with a customer there and then. I do not plan to hand out the cards – I don’t consider them disposable. It’s just a different way to share information, showcase my design capabilities and offer novelty value. It’s uniquely mine.
Constructing the card
I wanted to keep to the form factor of a traditional business card (85x55mm) and make it as thin as possible. For my version, I decided to make a sandwich of birch plywood around the tag sticker. I cut out oversized pieces of wood on my xTool P2S laser so that I could then cut to the card shape once laminated (avoids issues of lining up edges). To avoid a tiny ‘bulge’ in the card caused by the chip, I engraved away a shallow depression on the reverse of a 0.8mm ply sheet (xTool F1 Ultra):
Having programmed and checked the NFC sticker, I stuck it into the depression and then glued a thinner (0.4mm) piece of ply to the back, clamping it in place between sheets of MDF to dry. I used my finger to smear the glue evenly over the wood, but avoided the tag.
Once dry, I checked out which end the tag was by holding it up to a light. I put the laminated ‘cards’ back into the P2S (thick side up) and cut out the final outline. One of the paired pieces slid apart during the clamping process, but I was able to just fit in the card shape and rescue it. This is precisely the reason I cut oversized pieces initially and cut them down to size later.
Then it was time to engrave the QR code and name details, for which I switched back to the F1 Ultra. Once engraved, a quick sand with fine sandpaper across the surfaces and around the edges cleans off any char marks and helps return the contrast between engraving and unengraved wood.
Other learning points
Wood thickness and engraving settings: I originally wanted to get the completed card as thin as possible by laminating two 0.4mm ply thicknesses. My initial engraving settings put pay to this idea though… In the following photo, you can see the underside of the engraving has been scorched through to the back surface with the imprint of the honeycomb laser bed there for everyone to see. Not at all what I wanted. This was a consequence of the too-thin material and too much power. The faint shadow above shows a second attempt, but it was still too obvious. I dealt with this by engraving into the thicker ply with lower power, higher speed and more passes to avoid the excess heating. A further complicating factor would have been that the subsequent QR code engraved on the opposite side would have eroded into the depression and the NFC tag, aesthetically displeasing, and rendering the tag defunct.
QR code generation: it is important to note that some ‘free’ QR code generators online are not at all. They cleverly and surreptitiously use their own URL addresses and then divert to the one you wish to use. This means two things: it’s an extra server to go through before the user gets to yours, and you are dependent on their service staying live. Both of which then require you to take a subscription out for what is available completely for free. On the other hand, if you want all the stats and other bells and whistles, sign up.
I ended up using qrsurge.com, which allows free design and download of QR codes without needing to sign up or subscribe. Test the QR code before downloading to ensure it works, goes directly to your site and is not a redirect. There are loads of different design options, from frames to using dots and dashes instead of the blocky style we most often see. There is also the option of changing the redundancy level. Higher redundancy means more, smaller dots, but it means that printing errors are more easily corrected. This is most useful when engraving wood, as defects or uneven engraves are less likely to produce errors when reading back in. I chose to add the studio logo in the middle, reinforcing the bespoke branding.
Other laser settings: The xTool laser software gives the opportunity to tweak a couple of settings. The first is particularly helpful when engraving wood, changing the angle at which the laser passes across the wood. I find that the traditional left-to-right movement can miss bits when engraving grainy wood. On the F1 Ultra, I set it to engrave at 30-degree increments to go across the grain. The other setting to be wary of is ‘smart processing’. This reduces the time taken to engrave, sometimes by half, by changing the processing algorithm and breaking up the engraving into smaller chunks. Unfortunately, the algorithm doesn’t quite join up the different sections. In the following pic, you can see the diagonal lines across the QR code: diagonal because of the laser angle, lines because of the missed bits between smart engraves. BTW, don’t follow this QR code. It’s one of the pesky redirect types which I didn’t notice until it was too late. It has now become a teaching point…
If your engraving isn’t quite dark enough, defocus slightly (2-3mm) and run at a slightly higher power at the same speed. As I’ve said before, material testing is paramount.
Costs: The NFC tag stickers are about 8p each. The birch ply is more expensive due to its thinness, and works out to around 85p per card. Laser time is negligible; glue similarly. Time is the predominant cost, with each card taking at least 30-40 minutes of hands-on time to complete. Cost price is therefore around £15 per card. This might not be a competitive price compared with commercially available products, but it is very bespoke.
Was it worth the effort?
In my view, learning something new is always worth the effort. I learnt a lot about the technology of NFC, QR codes and reinforced my learning about laser use on different materials. Working through the production process was also a great activity, planning the logistics of hiding the tag and achieving a working, pleasing to look at and handle, end product. Worth the price? Well, that’s up to whoever is paying the bills. If you’d like a bespoke, digital-ready, tactile and natural business card, you know who to ask…