Sixpence

I've got a few wheel sizes out here - in mostly official sizes but some custom sizes for my PB15 trucks. I can probably put something together if you are willing to test it. Just need the diameter in real units and I can work from there over the next few weeks.

Sure. IPA stands for Isopropyl Alcohol (Not to be confused with India pale ale beer). Methylated Spirits and Isopropyl Alcohol are denatured alcohol and have uses ranging from cleaning, to paint thinner. Typically they are a mix of alcohol, a little water and poison additives. The poison additives are so you can't die from alcohol poisoning - they force you to vomit. Kirschwasser - that's not going to be 100% alcohol either and will probably have other things in it you don't want on your track. Not to mention very expensive per litre. So personally I wouldn't use it or recommend it for cleaning track.

Lego officially recommended the use of a pencil eraser to clean the track. You can see it in a number of the included track manuals or train set's instruction booklets from both the 9V and 12V era. For the love of all that is good do not use a model train track rubber! Model track rubbers are like running low grit sandpaper over your track and are designed for large scale outdoor track or older metal track that is a single solid material. The metal alloy and plating of most modern metal track and the lego track is not designed for use with a track rubber. Years later my oldest track is having issues where the outer coating of the meal is so damaged from a modal train track rubber that it's starting to react and turn green. If I had a time machine I would go back and slap myself for using a track rubber as a kid/teen on what at the time was hundreds of dollars worth of track. Do not use anything that is abrasive or that scratches the track as you will damage the tracks metal plating and create more holes for the dirt to get stuck in. The more dirt that gets stuck the more the plastic wheels will side that dirt around on the track. So also remember to clean your wheels which will help to keep things clean as well. IPA and Methylated Spirits are not electrical cleaners and will actually make the track progressively worse at being able to transfer electricity from the track to the wheels. Both chemicals have other things in them that will react with the metal track. If you really want to use a chemical cleaner then something like Inox which is designed to keep things conductive. Clean track is good but conductive track is better - singed another grumpy Australian! (You'll get that joke if you've seen this video).

So after a redesign and some testing here's the final model: Available from here: https://www.highiron.works/parts/6-wide-axle-holders I'm not selling the physical item as I just don't have the capacity. The models are however available for download (Link above). If you don't have a 3d printer you can use either a local service or one of Thingiverse's 3D print partners. If you need ball bearings you'd be looking for "MR52ZZ 2x5x2.5mm". The wheels are from bricktracks and come in a few different colours.

Or just use one of these: https://www.highiron.works/parts/6-wide-axle-holders No lego was hurt in putting these together, easy to assemble and align bearings, multi insertion ready and no cracks.

So Just a small update the ball bearings arrived last week and I've had a chance to update the design to use them. Features include: an ejection slot so that ball bearings can be replaced or serviced outside the frame non-cracking friction fit printed with a slightly smaller 0.3mm nozzle to improve accuracy - which means the studs now have a slightly better clutch when used with official lego parts I've also had a number of original non-ball-bearing sets start to squeak so that design won't be moving forward. I'm really happy with how the ball bearings behave; so that is what I'm going with. See images hidden below

Yes, I have made a few changes. I've started printing into two separate parts to reduce print waste fix an underside separation issue where the material was splitting due to being printed on the support material. This won't be possible for the models with the sides so I'll have to live with a slightly higher defective rate or let the 3D print farm solve the issue with better slicer settings slightly revised end cap to hold the wheelsets in I'd probably start considering having 3 studs on the side stud model but now that I've sorted out a spacing issue My current testbed of 20th Century BR/QR Rail wagons seems to be doing ok using them. They're not for sale yet as I haven't found the right 3D print farm partner yet and still trying to finish testing to make sure I've resolved a squeaking issue. It probably wouldn't be too hard to modify what I have to accept ball-bearings. Probably wouldn't be too hard to do a 1 by 1 or 2 by 1 brick with the correct size hole/s either. Although something that small might be a little hard to keep stuck to the print bed. The hole widening of a technical axel hold looks like a really painful process and one that would be much easier to print. I've found that there are a few places on eBay and AliExpress that sell the right sized ball bearings - although I believe the model number is MR52ZZ. I'm familiar with BT as I'm using BT wheels as I can't get the FDM wheel prints to stop warping - I'd have to move to a resin printer I think to fix that issue and be able to print straight axel holes. Although I can print the Big Ben Bricks wheels clones I designed and they stay flat so it's probably a thinness issue but I digress. There is only one reason not to use ball bearings I can foresee and that is I can run 4 wheelsets inline because of the side to side movement without ball bearings holding the axel in place. General Project Update I've had a little trouble getting some test parts out of lego for couplings which have stalled my testing efforts (this part). Two of the earliest axel holders I printed (revision 8 units) developed a squeak which I'm a little concerned about and why I want to test a little more. Although the design changed slightly since then so I'm hoping that it's just an issue with the early print runs. This seems likely because swapping into a revision 10 or 9 looks to have solved the issue. It's only happened with 2 out of 40 units but the majority are either a revision 9 or 10 which haven't failed in the same way yet despite only being printed a week or two apart. 3D print farm wise I'm still looking, as the local place, I was going to use seams to have closed down. There are a few other locations within my area but they look a little iffy. I've got a few other 3D print lego train-based projects running in the meantime; which once parts start arriving I should be able to start talking about. I'll give the ball bearings ago and I'll probably find a print farm somewhere in 2021.

For a while now I've been working on creating replacement axel holders for lego train wheels. It all started when I got back into the hobby and ran out of train wheels. Looking around my local area (Australia, Queensland) the 1 or 2 clubs that used to be around disappeared so there wasn't anyone I could trade or buy them off. I then remembered brick link but I couldn't get the cost down to below $5-8 pre-unit shipped. When you want 100 or 50 or 24 of the $8-5 a peace starts getting really expensive. I then tried to order them from lego but they weren't shipping bricks and peace due to the outbreak. Shortly after trying to order directly from lego, they also discontinued the part I wanted. So a few months of design later, I now have a number of wheel axle configurations. I printed the last prototypes this week and I was a little surprised that they felt smoother than the official ones. Although having said that my existing lego wheels are all 9V or RC so they are really old. I have a version with no sides, a version that is designed to imitate the existing one from lego and one that has studs on the side that is primarily for snot builds (8/9/10 wide). I'm now moving into a phase where I'd be sending them out to an ABS plastic print farm because they take between an hour and 1hr+45min to print. Initially, I wasn't going to sell them but I was wondering if there might be a demand? If there was a demand what colours other than back people might be interested in? Other Questions Welcome.

As someone who actually tried it - do you need special track for smaller flanges? well no, the gaps in between the frogs on the points are just small enough to allow small flanged regular-sized wheels to roll over. It's not the smoothest transition as you go over but it works. I also had a steeper wheel slope so that there was less rubbing and the wheels sets centred correctly. If the wheels were about 2-3mm larger the bump probably wouldn't be an issue. If you scaled the interior of the wheel up to 20/21mm diameter and had and the flange at 23mm diameter that would put the wheel in the ballpark of running nicely over the frog gap in the points. I'm not really sure how the large train's wheels would go with a smaller flang - I don't have a platform to test those on at the moment; as my two emerald night sets are broken down and used for other projects. The main reasons I decided not to go with custom wheels with smaller flanges was: I originally had 3D print warping issues where the print wouldn't stay flat on the bottom It was easier to order the wheels and axel sets from BrickTracks than to source the axels and have 100 or so wheels printed on a 3d print farm.