[vsaravind007]

Hello TeamBHP family, hope everyone is safe in these troubling times.

It's been long since I've posted in the forums, mainly because I couldn't find time to do any DIY on my car and(because) I got married, adding on to the responsibilities! This was changed thanks to the COVID-19 "Be At Home" situation. Since a lot of travel plans were cancelled, I had a lot of time at hand suddenly. During this time, I took a few days to calibrate and tune my 3D printer that I bought a while back, making it dimensionally very accurate and prints repeatable. I was using this printer pretty much as-is previously for creating small brackets, knobs, tool hangers and gardening pots for my missus. If you're a heavy DIYer, you might have one already at home or some even have them at their offices, these things are pretty common these days as they're very cheap and easily available.

The Problem
The electronic adjustment in the side view mirror on my Skoda Laura waas broken by a comprehensive car wash by me a few months back. I was cleaning the glass with a microfibre cloth with a bit of force to remove a tiny spec, I broke it.





This made the glass to swivel and tilt by hand. Though this wasn't an issue because even though the adjuster is broken, the glass would stay in place, so adjusting wasn't necessary because I use the car 95% of the time & it never needed adjusting. Still it was an issue because, if I wanted to adjust it, for example during reversing at a new place or something, I had to roll down the window and adjust it manually. Trust me, this was the only thing that is broken/non working on my Skoda from 2007! I enquired a few places about this side view mirror actuator, Skoda A.S.S didn't had them, they were interested in selling the whole mirror assembly. Picture of broken part for reference:




I saw a few online, ordered one from Aliexpress, but it never showed up. Saw a few on Ebay UK, but none had shipping to India. I fixed it for a short while with Superglue and a piece of cloth(you can see this botched fix in the above second photo, annotated in red), but it only lasted a few weeks. I stopped looking for a replacement part because it wasn't a problem that actually bothered me, I left it as-it-is for about 3 or 4 months.

The Solution
I was browsing Thingiverse(An online platform for 3D printable stuff) for a Skoda emblem for my wheel centre cap & accidentally stumbled upon this: https://www.thingiverse.com/thing:2138281 It was a replacement part made by someone for the exact same problem! I was actually amazed to see it online, I knew it wasn't a rare issue but never thought someone would design and make it. I quickly downloaded the model, it wasn't the same model as I later found out, but looked pretty much the same.

I couldn't resist the urge to print it and I did! Imported the file into Cura(Software used to convert 3D models to format understandable by the 3D printer) and printed the model. The part came out "OK" and it looked the same to me, I quickly took my tool box out and went to work, if you're to follow this, below are the steps:

Removing & Disassembling the unit

1. Remove the mirror by gently prying the glass ends by hand
2. Remove the mirror heater connector
3. Remove the 3 screws holding the actuator in place & use the controller knob inside the car, make sure that the linear gears stick out to the max before unpluging the blue connector going into it, you cannot manually pull them out.



4. Once the actuator is taken out, the broken linear gears are clearly visible:



5. Remove the rubber grommet around the actuator.
6. You'll have to separate the actuator into two parts to get to the linear gear, to do that you'll have to remove the white plastic piece(annotated in red) that runs through the middle with a bit of prying using screw drivers. Pry at the area pointed by the yellow arrows in the below picture, pry towards the piece to bend it slightly so that it is released, there is another tab in the middle, which will come out easily once the two ends are free:








7. Pull out the linear gear out of the actuator in bottom part and the broken spherical lock from the top part:



Printing The Part

Like i mentioned previously, the part that I found on Thingiverse isn't exactly the same, I had to make a few minor adjustments. The part that was there in my car was a bit longer, about 2mm and the spherical lock placed a bit higher. The part I got from Thingiverse is not a full model, its an STL file which is like an output, if you think about Photoshop, an STL file is like a JPG file that is exported from the original PSD file, you can't adjust much of it, but can adjust the size. Same story with STL files, we can adjust the size in X/Y/Z direction. For this part, I resized the part to 110% in the X direction and 105% in the Z direction, which resulted in a slightly longer part with a minor height bump:





I had to go through quite a few iterations with the print settings like layer height, retraction, wall height and other to make the part fit nicely. Good thing was that, this part is a small one, each iteration took only 10 minutes max, if it was a larger part, it would've taken hours!



Once i was happy with the fit, I had to make a few passes with a small fine grit file to smoothen a few rough edges and to make the gear ridges sharp. If you look closely at the printed part, you'll see that the gears are not deep enough, but on the original part, the gears are deep and the tooth are sharp. This is unfortunately not fixable because I was already printing on the lowest possible resolution on my printer, Creality Ender 3 Pro.



Re-assembly

Re-assembly goes in reverse, but before that can be done, the 3D printed part had to be tested fitted. To do this, I had to go to the car, connect up the actuator & use the control knob. Checked it a few times:

https://youtu.be/rV46q8oMBTA

Once I was confident enough, I printed another pair with correct print settings and finished it with fine grit sand paper and pieced it all together:

1. Insert the linear gears by running the actuators with it connected to the car. Extend the arms fully & take it to your work bench/area:



2. Clip on the spherical locks into the top part






3. Once they're secured, press in the white locking part



4. Before assembling everything back again, make sure to do a test run:

https://youtu.be/j37LIQsu1og

5. Assemble everything back to the car:



6. Profit!!

https://youtu.be/wwuSpxbxjw8

Printer & Print Settings
I have a Creality Ender 3 Pro
Printed in White PLA by Creality (Any good quality PLA would do)
Part was printed at 0.12mm layer height with a 0.4mm Nozzle, 100% infill and 1 top layer.

Caveats

1. I printed this part using PLA plastic, it is a bio degrade-able plastic that breaks down in the presence of water and heat - big NO-NO for external automotive applications. I used PLA even though I had ABS because, I couldn't print ABS reliably due to the lower ambient temperature due to the rains, ABS requires an enclosed printer and needs to be printed at around 250 degree celsius. My printer is an open style one that sits outside in our car shed, without enclosure, I cannot print ABS if the ambient temperature is below 30 degree celsius. I'll be printing this in ABS or Nylon in near future and will be ready with it hopefully when this one breaks!

2. Its very noisy! This was surprising at first, the fixed side is very noisy when adjusting, I haven't added any grease because that'll quicken the breakdown of PLA. I suspect this is due to the vibrations generated being transmitted to the outermost part through the printed part, nylon is flexible compared to PLA and kind of dampens it, again just a theory.

Closing Thoughts
I'm not sure about the reliability of this print mainly because its exposed to the elements. Even though its kind of protected from direct sunlight and rain, it is possible for the PLA to break down and undo everything that I've done. BUT! It was well worth the effort, its like a dream to be able to download something virtual, physically make it and use it to fix a physical world problem! I'm sure you'll find it interesting, I would say that a 3D printer is an essential tool for any hardcore DIYer, would highly recommend it to anyone who is interested enough and have the patience.

Thanks for reading!

[blackwasp]

Originally Posted by vsaravind007

I have a Creality Ender 3 Pro
Printed in White PLA by Creality (Any good quality PLA would do)
Part was printed at 0.12mm layer height with a 0.4mm Nozzle, 100% infill and 1 top layer.

First time I'm seeing 3D printing being involved at a such a DIY scale. I knew that 3D printing had its potential, but your post have reaffirmed it. A lot of older cars with broken plastic trims, parts and smaller issues could be resolved thanks to this idea.

1. I printed this part using PLA plastic, it is a bio degrade-able plastic that breaks down in the presence of water and heat - big NO-NO for external automotive applications.

Let us know how it holds up. While not a permeant solution, this should do till you can come up with a way to print the ABS version.

2. Its very noisy!

This is interesting. Is this just due to the lack or grease or any other reason? I feel there could a minor size difference with the actual part and the printed component as well.

I'm not sure about the reliability of this print mainly because its exposed to the elements.

It should be good enough for the time being. Fascinating DIY there. Thanks for sharing.

Cheers.

[androdev]

Cool concept in action, enjoyed reading it. Like you suspect, the durability of the plastic would be a concern. Assuming you have all the pieces of the broken part, I feel fusing them together with some resin/epoxy, etc would serve you better.

[--gKrish--]

Originally Posted by blackwasp

This is interesting. Is this just due to the lack or grease or any other reason? I feel there could a minor size difference with the actual part and the printed component as well.

Not only due to lack of grease but also due to inaccurate teeth and thus noise during meshing. We have a 3D printer in our college and we tried making some Geneva mechanisms in it. It used to be noisy and a bit jerky because of inaccurate teeth. Straight teeth gears are inherently noisy and more prone to vibration. It is the reason why even the original part is noisy to some extent.

[jothishX]

Cool DIY. Printing this small part will be difficult in ABS even on high bed and hot-end temperature. I've tried using cardboard boxes, added brims, but still warping happened.
If your PLA is good quality, it should last atleast sometime. Use silicon grease to smooth it out and remove the vibrations and sound.

[vinay5795]

I never could have imagined stuff like this was possible.
Lot of such small parts are obviously not sold my manufacturers. The only other way to source this without buying the whole assembly is to go to a workshop and look around for broken mirrors to source a similar part. Hope to see something like this go mainstream as it would save tons of money and do good for the environment as well. But it wouldnt make the OEM part suppliers happy. Lovely DIY

[Rakmo]

Great Thread! what better use of a 3d printer than to solve small household/DIY problems.

I too own the same Ender 3 printer, for casual use of printing some good models, utility items from thingiverse OR designing simple parts in CAD and printing them.

Regarding ABS, I have been printing with ABS too and with small size parts, results are good(keep the room AC, FAN off for better results). In this application, ABS or nylon is better than PLA, as its brittle and not a good temp. resistant.

[KPR]

That's a new type of DIY we've seen. Can you share the details printer you have, where from you've purchased it? Maybe a small review about the product and it's accessories?

[vsaravind007]

Originally Posted by blackwasp

First time I'm seeing 3D printing being involved at a such a DIY scale. I knew that 3D printing had its potential, but your post have reaffirmed it. A lot of older cars with broken plastic trims, parts and smaller issues could be resolved thanks to this idea.


Let us know how it holds up. While not a permeant solution, this should do till you can come up with a way to print the ABS version.


This is interesting. Is this just due to the lack or grease or any other reason? I feel there could a minor size difference with the actual part and the printed component as well.


It should be good enough for the time being. Fascinating DIY there. Thanks for sharing.

Cheers.

Thank you Blackwasp, you right about the plastic parts getting brittle on the older cars, often times a lot of tiny parts will break off or wear down, parts won't be available or will be very expensive.

Originally Posted by androdev

Cool concept in action, enjoyed reading it. Like you suspect, the durability of the plastic would be a concern. Assuming you have all the pieces of the broken part, I feel fusing them together with some resin/epoxy, etc would serve you better.

Thanks androdev, I don't think fusing them would work, mainly because the nylon gears have already become kind of brittle, if you look at them, a few of the tooth are missing. Also nylon doesn't stick well to adhesives.

Originally Posted by --gKrish--

Not only due to lack of grease but also due to inaccurate teeth and thus noise during meshing. We have a 3D printer in our college and we tried making some Geneva mechanisms in it. It used to be noisy and a bit jerky because of inaccurate teeth. Straight teeth gears are inherently noisy and more prone to vibration. It is the reason why even the original part is noisy to some extent.

Hi gKrish, if you look closely at the original gears, they're indeed helical, helix angle is low though making them look straight, same with the replacement part, they're helical. Problem here could be that the printed gear tooth are not deep enough like you said.

Originally Posted by jothishX

Cool DIY. Printing this small part will be difficult in ABS even on high bed and hot-end temperature. I've tried using cardboard boxes, added brims, but still warping happened.
If your PLA is good quality, it should last atleast sometime. Use silicon grease to smooth it out and remove the vibrations and sound.

Hi jothishX, I'm able to print ABS if the ambient temperature is 30-32, if its anything below that, the print will fail. I'm using masking tape to aid adhesion, warping and layer splitting had happened to me as well. I found the best way to print ABS is to use masking tape + a wool cloth over the printer I'm currently working on a 3D printed CNC machine, hoping to machine some aluminum!

Originally Posted by vinay5795

I never could have imagined stuff like this was possible.
Lot of such small parts are obviously not sold my manufacturers. The only other way to source this without buying the whole assembly is to go to a workshop and look around for broken mirrors to source a similar part. Hope to see something like this go mainstream as it would save tons of money and do good for the environment as well. But it wouldnt make the OEM part suppliers happy. Lovely DIY

Thanks vinay5795, hope the OEMs won't come after me!

Originally Posted by Rakmo

Great Thread! what better use of a 3d printer than to solve small household/DIY problems.

I too own the same Ender 3 printer, for casual use of printing some good models, utility items from thingiverse OR designing simple parts in CAD and printing them.

Regarding ABS, I have been printing with ABS too and with small size parts, results are good(keep the room AC, FAN off for better results). In this application, ABS or nylon is better than PLA, as its brittle and not a good temp. resistant.

Thanks Rakmo, yes its a quite useful tool to have if you have the patience. I have ordered Petg, should be better than PLA.

Originally Posted by KPR

That's a new type of DIY we've seen. Can you share the details printer you have, where from you've purchased it? Maybe a small review about the product and it's accessories?

Thanks KPR, I'll try to write a detailed review about the unit I have, meanwhile, below are the details you asked:

Printer: Creality Ender 3
Bought from: Amazon
Cost: Around 20k
Filament Used: PLA, made by Creality

Thanks everyone!

[Jeroen]

Excellent job! Thanks for sharing. It will be interesting to see how long it lasts. At least that is my limited experience from some years ago when it comes to 3D printing.

I have a little experience with 3D printing. Two mates and myself bought a 3D printer some years back. We were interested in re producing some small parts on our classic parts that were not available any more. Little clips that hold panels in place.

Getting the shapes right was fairly straightforward. The problem was lack of elasticity. These clips turnded out way to brittle and broke easier than 50 year old plastic ones.

3D printing has come a very long way and I need to start looking into this again. Modelbuilders are using it extensively for very complext shapes too. Few of them own a 3D printer. You just design what you need on your computer and send the file over to specialist 3D printer companies. So you have essentially access to the most modern versatile 3D printer at a fraction of the cost.

I have seen 3D printed parts entering the classic car part some years ago. It is really a fascinating technology with so much potential not even remotely being used. Give it time.

Of course, there are industries that have alreay introduced 3D printing in an industrial way, e.g. aviation springs to mind. I am sure those parts will last!

[2000rpm]

I have been hearing about 3D printing for a while now, but was thinking that this will be just another Digital Fad, as I saw no Real use cases.

But thanks for sharing this. This really helps broaden our perspectives.

[vishwasvr]

Back in 2016, I had got a small plastic hook which does the final locking in of a sunroof system for a 2008 BMW X3. Navnit BMW quoted more than a lakh to replace the entire assembly. They did not even bother to open and diagnose the problem. When I had opened it and checked everything was working fine except this one small hook which lets it sit flush. Because of this hook, it would get displaced when the car went over any speed breaker. There were two of the hooks on either side so I used it to mirror the part and got it 3D printed and voila! Worked like a charm! Costed me 1200 bucks if I remember it right. But the cost of bringing the roof down (literally) was fairly high. But still worked almost 60% cheaper than what BMW quoted.

Unfortunately I don't have a picture of it just now. Will share it when I find it.

[vsaravind007]

Quick Update

Its been 5 months since I've done the fix. I've washed the car multiple times, given it for a professional wash a couple of times, had a few highway drives, driven through heavy rain & the car was parked in direct sunlight for a few days. Though I've adjusted the mirror only few times(also the auto adjustment with seat memory when my wife takes it for a drive), the 3D printed part is still holding strong. The noise I observed after the fix has subsided & hardly noticeable now. Overall the fix is a success!

I've acquired an enclosure for my 3D printer and now I'm able to print in ABS plastic in case this part fails in future.

Stay safe everyone!