Hot Wheels custom cars

As I'm perusing the world wide weberverse, I found out about another hobby that has been doing the rounds for … oh I don't know, probably for as long as die cast cars have been around.

There are heaps of people who customise and make their own Hot Wheels (and other brand) cars, and it looks pretty nice.

I'd already seen a bunch of tutorials on how to DIY waterslide decals, so that's entirely doable. Drilling out the rivet and either gluing or tap and screwing the base back on are both things I can easily do. Stripping off the paint is likewise relatively straight forward.

The painting … that's a bit harder and not something I have much experience with. I've never used an air brush, but it looks relatively straight forward. The basic techniques at least, I'm assuming that like most things, one gets better with practice.

The down side is that a proper airbrush kit with compressor is over $150 for a basic kit. A bit out of my price range, and that's before buying paints and other things.

The good news is that if was to pick up a gravity feed air brush (as opposed to siphon type) online, they can work with relatively low air pressure - and one hack that I've seen is to use a fish tank air pump (instead of a proper compressor) and adding a 2L or 3L plastic soda bottle for a reservoir. It seems to work, and for something like painting little toy cars it could be done. Considering that we already have a spare air pump floating around, I could cobble something together to run a little $20 air brush gun.

Would the results be good? Probably not. But it could work as a first step approach, and a way to practice. I did have a hunt around to see if anybody was selling packs of old cars in bulk on the cheap, but everybody seems to think that every car is a hyper-collectible classic. Or they are pretty cheap listings but have $100+ postage due to coming from the US or England. Basic cars are only $2 from BigW, but it seems a waste to pull apart and strip a brand new car.

I might have to check out the flee markets or keep an eye out on the classifieds to see if there is anybody selling or giving away old cars.

Or not. We don't really have the spare money for me to be wasting it on frivolous things like this. I'll have to keep hunting and find something cheaper...

And the funding says no

I had my heart set on doing thingies with metal. I'll stop calling them "thingies", the proper term is signature item. But yeah, I had my heart set on making my signature item out of metal. I recon it would have been good - had a bit of weight, good 3D relief and been sufficiently interesting that people who saw it would have liked it.

But I don't think it's going to happen. Melting aluminium requires a lot of equipment that would cost a fair bit to set up, and even if I had all the gear it wouldn't have given me the level of detail that I want (sand casting requires a lot of clean up work after it's cooled down to make it look good). Fairly straightforward to do with shapes and parts, much harder on a small, coin-sized item with lettering and fine design elements.

Using pewter would have almost given me the level of detail that I want, the lower melting temperature meant that I could get by with pretty cheap tools - but the silicone moulds need to be made of special high-temperature stuff which is hard to get and expensive; plus lead-free pewter is pretty expensive. Pewter made with lead I could get pretty cheap (around $20 a kilo) but that would have been highly irresponsible of me, to put things out in the wild that unsuspecting people or kids could pick up and play with that were made of lead.

I had decided to go with casting with epoxy resin, and had found a great way of running an airbrush on the cheap (use a fish tank air pump {which we have a spare one lying around} instead of a compressor), or go even cheaper and use inks to stain the resin instead of painting it. Still out of my price range. :(

So I'm going to go with little cheap plastic tokens, with a printed inlay.

It's depressing, and I will definitely be looking at the results and thinking of what they could have been. But it's better than nothing I guess. Half the point of getting into geocaching was to have an excuse to make stuff. I could still make stuff without going out and looking for caches - but the funding would still say no.

Maybe one day...

Thingies

Apart from the options already mentioned in my last post, there is also lost wax casting. This can tie in with either pewter or aluminium casting and works well for complex shapes that won't work with a two part mould. Although the wax can be partially reclaimed and padded out with cheap candle wax (the proper wax comes in various grades, and buying softer stuff can be offset by melting in harder candle wax), it's still too expensive.

So it looks like we're back to the "custom poker chip" idea. Or something similar. I found a supplier of blank, white plastic tokens. I've ordered their smallest quantity, a ten pack, to test how well it works.

I had found a supplier of "blank" poker chips in baches of 120 chips for $12 - which amounts to 12c each. This is in line with buying the poker sets from BigW or KMart - they have 200 and 300 chip sets for $20 and $30 respectively. The ten pack of blanks cost me $3 (including postage) so that's 30c per blank, but they also have 100 packs for $16 (16c each).

That's still higher than the blank poker chips (which aren't blank, they have designs on the borders) but the poker chips have the big disadvantage that they come in sets of four colours. The white ones came out okay, the green ones looked okay, but the blue and black ones were very meh. So being able to buy all white ones makes printing designs much easier.

Decisions, decisions

Okay, I have a bit of a conundrum. As I've mentioned before, I'm getting into this whole Geocaching craze (okay, that's a slight exaggeration since this hobby / game started twenty years ago and there aren't that many active players at the moment). Part of the appeal for me is a chance to flex my creative muscles and make stuff.

The reason for this is that part of the game is "swag" (Stuff We All Get), which is basically little trinkets that people leave in the caches so that other players can swap around (a bit like "take a penny, leave a penny" setups). The idea is players put in things they think are worth something and other players can swap them out for things they think are of roughly equal value. Of course, not everybody is going to put the same value on something as another person - but we'll ignore human psychology for the moment.

For me, I don't plan on taking any swag, and I don't have the funds to go buying a bunch of stuff to drop off and give away (as much as I would like to).

So I'd prefer to custom make little thingies. At the moment the main thing I'm looking at is "coins". Not money, some custom made little things that I can keep updating and changing the design on (such as putting the current month and year on them so if other people find them, they can see how long it's been in play).

At the moment my main priority is cost. And I'm looking at six different options.

1. I can print out stickers at home and put them onto little plastic tokens or poker chips. I'm pretty much already set up for this and have produced a couple. I need to refine my process, but it's the cheapest option.
2. Etching aluminium stock. This I've mentioned in prior posts, and I'm sort of set up for it. My results so far have been pretty poor, but I think I may have found a solution. I've ordered some dry photosensitive film, so now waiting for that to arrive. It is the cheap Chinese stuff, so not sure how well it'll turn out, I'll have a play with it when it arrives and hopefully get something better than I'm getting now. If it works as intended, I should see some halfway decent results.
3. 3D printing. If I had a 3D printer, this would be the "ideal" solution, because I could just keep updating the design each month, and make relatively intricate models. The downside is that any machine I can realistically afford will not print the level of detail that I want.
4. Epoxy Resin. This would give a great level of details, but the epoxy is pretty danged expensive. I'd need to start with a 3D printed master, but there is a new re-usable resin available. It works by heating and pouring, so that after spending a month making that version of my thingy, the mould can be melted down and re-used. So the set up costs are low, the mould costs are low, but the resin is around $90 for 250mL.
5. Pewter casting. The great thing about pewter casting is that since it is relatively low temperature metal, I can get away with bodging together some rather cheap tools to get up and running. I've already priced up all the things that I'd need, and it totals out between $100 to $150 depending on sales and how patient I am. The down side is that in order to make moulds, I'd also need a 3D master, and the choices for mould materials are either plaster (low detail level) or silicone rubber (moulds are permanent). The cost of the mould making material is about $100 per 1L, and making new moulds each month could get expensive. Also, pewter is available in cheap (50% lead) and not-cheap (lead free). If costs is my main priority (which is is) then lead is the answer, but if I'm going to be making stuff to put out there that can possibly be handled by kids, then it would be irresponsible to use lead, even if I painted it. Lead pewter is about $25/kg plus postage, and lead free is about $60/kg.
6. And finally, aluminium casting. Possibly give the best results, and has the cheapest material costs (we already collect aluminium cans, so it'd be cheaper to let me melt them down rather than collecting the 10c each and then buying raw material). However, the set up costs are quite steep, over $400 at a bare minimum (and cutting a few corners on safety - not a good idea!) Good for low production runs, because if I 3D print my master, I can use it to make a bunch of sand moulds, then do one large pour and do a bunch of coins at once. Fairly low cost per coin and no chemicals in the house like with epoxy resin … but it has that steep initial cost.

So, not quite sure which way to jump. And odds are, whichever technique I try first, I'll need to stick with that system because I won't be able to afford to switch to another. I just need to make sure I focus on my priorities:

• Affordable: my income goes towards the house, there isn't a lot left over for my interests.
• Safe: I can't have my chemicals or flammable materials injuring myself, my family or any animals.
• Adaptability: I'd rather not keep cranking out the same thingy all the time, I want them to be different from month to month.

Having said that, I did send an email of enquiry to a Taiwanese engineering firm to see how much it would cost for them to produce a steel mould for me. If I wanted to do aluminium casting, then I can't make moulds out of silicone rubber or plaster due to the heat, and sand leaves a grainy texture that needs to be machined to make it look good. A steel mould gives brilliant results - if you can afford to get one made!

Also, I want to build gadget caches, but that's a whole Pandora's box I don't want to open just yet...

More attempts

Well, I've successfully found more ways that salt etching doesn't work. Or more acurately, the toner transfer.

I tried a few variations on the dry transfer and hot iron method, but the toner wouldn't take. It either won't mount onto the paper, or won't transfer onto the metal.

I'm going to have one more go at doing a transfer with the soak method, but then infill with something (sharpie? nail polish?) to try and compensate for the thin layer of toner.

Which I'm 80% certain is the cause of my issues - the printer not laying down enough toner. I could try printing at work, but even if that proved an instant success, it would be of limited value to me. It would be a pain to have an established method that works great but then have the work printer replaced, or get sent to work at another spot where they don't have one.

If the next attempt is a fail, I might give in and drop a few dollars on proper photosensitive film and do up the transfer that way...

Second attempt at salt etching

Curses! I thought I might have been getting a decent result. But, I'm getting ahead of myself.

Current biggest issue is getting a decent resistor onto the aluminium with enough detail that I can get crisp lettering. I think at the moment the issue is that the printer that I have is either low on toner, does not deposit enough toner or is set up to maximise toner and I can't turn it off.

So the first thing I tried was the first method (glossy magazine paper) with a bit of nail polish remover. I also added pressure by using a clamp I picked up from the hardware store. However, I feel that my mistake on this attempt was that I used two bits of metal (the aluminium stock and bit of scrap steel) and it didn't put equal pressure across the toner.

Result: toner didn't stick.

(Also, didn't clean up the metal first either, which can't have helped.)

Second attempt today was using the second method (back of sticker paper - waxy type). This is the one that is supposed to give the best results. The immediate issue was that the toner didn't stick to it going through the printer. Not what I was expecting, I poked around the settings a bit and managed to get a bit of toner onto the paper. The result was … lacklustre.

So I went back to the first method, but this time I put some padding paper between the paper carrying the toner and the steel sheet, and this time I managed to (finally!) get a decent amount of toner onto the aluminium. Yes!

So hooked it all up, got the juice flowing and the result was … about the same as the first time.

It's definitely an issue with the toner. It isn't on there thick enough to stop the salt water from eating away at the aluminium, which leaves it with that chewed out look and rough lettering. I can't think of any other way to get the amount of detail on there that I am after other than printing it. I was looking at the photoresist film, which could work. But that would require buying the film, plus some UV light(s) and who knows how much more equipment. I know we need to buy more toner for our printer, but there should be plenty of black.

I think for the next effort, I'm going to have to try a heat option. Which will either mean investing in a hot air gun or using the oven. Toner should need about 100c to melt the toner, the trick is to not burn it. More experimentation needed!

Custom stickers! Sort of...

Yes, this is another Geocaching post. :)

With Geocaching, there are different levels of commitment to people who want to play (read: decide how much money you want to spend), and one of the things which is "a thing" in the game is to drop swag in to caches for other people to find (and possibly move around). From what I've seen, swag can vary between something really nice and expensive like a collectible coin to assorted "junk" (cheap stuff from the dollar store like little plush toys).

As much as I would like go throwing around wads of money and buying toys and keychains and other cool little knick-knacks to give away, I simply don't have the money for it. So I figured I'd try and make (modify?) existing things to hopefully make them a bit more interesting. The level I'm aiming at is interesting enough that someone sees it and goes "that's interesting" but not so interesting that they decide they want to keep it and add it to their collection! It's a fine line to aim for (made a bit harder that one person might look at, say, a hot wheels car and go "meh" while another might go "yes, score!")

So a while back, we found one of those cheap poker sets that someone threw out during verge pickup, so I used this tutorial (YouTube, 2min) to make a couple of little stickers to put on the middle blank part of chips:

So far, the cost for these is:

• Poker chips: "free" (would be approx. 10c each to buy more, in blocks of 200)
• Packing tape: $6.45 (I used about 20cm and have about 60m left)
• Toner: negligible amount (though I need to buy more toner anyway)
• And an afternoon of time... free? I had some spare time...

With these little thingies that I'm making to release out into the wild, I'm trying to keep my costs down to a minimum, due to not having a lot of spare money. However, I'm classing this as both a hobby (having fun) and being creative (making stuff). I've already had a go at etching aluminium (which I need to refine, but the concept is sound) and now I've made these stickers (I was aiming for waterslide decals, but these will do for now) and odds are that I'll want to figure out how to make other stuff on the cheap.

With these, the only thing holding the tape (and toner) onto the plastic chip is the residual glue from the tape after dissolving the paper backing (and on these I wasn't as thorough as I should have been and found there was still a bit of paper on there after it dried). I'd like to add some epoxy resin over the top to really make them pop, but another consideration apart from cost is not getting involved with too many toxic chemicals. That's why I went for salt etching instead of acid etching (which is faster).

I figure that I might need to drop a few more dollars and get a can of spray lacquer or other sealant to make the stickers a little more robust … but that'll be something for another day.

Salt etching aluminium

Due to varied reasons (one of the main ones being a desire to create something), I wanted to try my hand at etching aluminium. I've had prior experience with it from one of the places that I used to work at and from College, but I was hoping to avoid having to use Ferric Chloride or other strong chemicals. After a bit of browsing I found that it is possible to do with salt water and a bit of electric current. That seemed like a better idea than to be using toxic chemicals (and then trying to dispose of them).

The first couple of prints failed because I was trying to print an Australian flag, but the detail was too fine. My very first print I rubbed the paper too hard and it ripped, so I scrubbed that one. The second one had many defects of missing toner or details covered by paper pulp. I used magazine paper, and that wasn't blank so some of the toner from that ended up filling in what was meant to be blank spaces.

For my third attempt at a print, I opted for large lettering, but even that was fairly dull and blurry once transferred onto the ali.

The setup … looked dodgy as anything!

Basically running a 5V DC power supply. A bit dodgy to have a stainless steel knife in a salt water bath along with the piece of aluminum being etched. I could see it not taking much fort things to shift around and get a short.

I did tape the knife to the side of the container to try and reduce the risk. Long term, I'd like to maybe get a holder 3D printed or something in order to make it safer and eliminate the chances of a short. But that's a long term thing - right now I'm trying to keep my costs down to a minimum. Current spend: $2. Not counting prior items that I already owned (such as a multimeter to check the polarity of the wires).

The result … is less than what I was hoping for.

I'm 95% certain that the reason for the failure was not enough toner on the print. I needed to use a destructive method (soaking in water) to remove the paper backing, I may need to explore other methods to get a cleaner deposit of the toner onto the aluminium. A pretty decent etch (depthwise, I mean) for only a few minutes of effort.

The end goal is nice crisp writing, and I think I am going to either need better transfer medium to get the toner onto the ali, or a better printer. I think buying toner is going to be my next step, unless I can find another option of paper I can use. Fingers crossed!

Geocaching

Went out today for my first geocache hunt. There aren't too many around where I am, but I was able to find my first two.

Currently planning to see if I can pick up a trackable traveller (they cost about $6 each, give or take depending on the type you get and where you get them from), and see if I can get it all the way out to a friend of mine who live in the USA.

We'll see how far into the hobby I get, money is always an issue and I tend to plan bigger than I can afford.