A better cupholder (cointray / ashtray) replacement

[Hejnfelt]

As many of you have probably seen, recently a custom cupholder was featured by DavesZed. This was particularly exciting to me as I was working on exactly the same project right at the same time

I wrote the creator on another forum in an attempt to offer a bunch of suggestions for the design that I had in mind in the hopes that maybe I wouldn't have to make my own. Alas I never received a reply and so I continued on my design.

My goal was to accomodate a standard phone lengthwise by creating a cutout between the cupholders so the space doesn't lose any functionality it had as a cointray. Additionally, Baldor's top surface staircase design just seemed like it would really stand out as non-OEM and I couldn't imagine having that in my Z4 fitted with a piano black center console. A smooth top surface, angled appropriately is what I was going for. Lastly I was wondering what angled sleeves could do to accommodate taller drinks like 0.5L water bottles and I wanted to try that. I've since realized a flat bottom is better but with appropriate spacing of the cylinders.

Today I installed V2.0 of my design which fits perfectly

The V2.0 is printed with a black smoke see-through resin at 50 micron resolution. This type of see-through resin allow seeing the internal workings of places that might still need sanding to fit. But it fit perfectly! Additionally I wanted to check whether resin might be a good fit for the final product with regards to fit and finish. While Resin surface finish is amazing and has great properties such as it's very tolerant to higher temperatures like a hot car in the sun on a summer day and is also completely moisture resistant to cold wet beverages, it's not particularly scratch resistant. It was a good test, but I think eventually I will revert to FDM materials for the final version (Not PLA!!!).

The V2.0 cupholder can accommodate all (standard) size modern phones lengthwise e.g. iPhone 14pro, Samsung Galaxy S23 etc.

As a stability test I have done multiple full throttle accelerations (390hp MHD stage 1+) and the full 0.5L bottle doesn't flinch whatsoever despite how it looks with the current angle

The areas that can improve are mainly the angle and diameter of the sleeves as you will see by the liquid level of the .5L Coke bottle.

I am already working on V3.0 which will feature slightly enlarged (exact size to be confirmed!!!) cupholders moved towards the gear stick by 2mm and be spaced further apart to accommodate ALL modern phones including the monstrous Google Pixel 7 Pro, iPhone 14Pro Max and Samsung Galaxy S23 Ultra lengthwise. This new spacing and sizing should accommodate manual gearbox cars better with more space in middle between the cylinders as well as accomodate a wider variety of cylindric beverages.

I am trying to achieve a specific diameter that will make the cupholder compatible with regular aftermarket silicone coaster inserts.

Is the community interested in buying the V3.0 when it's ready end of August?

My target price depends a little bit on the final filament choice and printing resolution. For those who are interested in knowing all the little details, I'm in between ABS, PETG and PET. I could go with Carbon fiber re-inforced PET but I personally think it's overkill and the material cost is twice that of ABS or PETG. As a sidenote, resin is 4x the cost of ABS/PETG so that won't go. ABS is very prone to warping just like polyamide which the original BMW cointray is made of... and it's also warped ABS is slightly stronger and more heat resistant than PETG but is also a bit more nasty to work with (harmful gases) and warped failed prints will increase the cost of successful prints.

A price under 45£ is definitely achievable but I would like to get down around £35 per piece. It depends a little bit on how many orders I get and how long the final print time will be which is related to resolution. Higher resolution takes 4x the time to print

If you're interested in buying a cupholder, leave a reply here or PM me and I will make a list while I finish the design of V3.0 and who knows, maybe it becomes V4.0 before I send them out

Anyway - as promised - pictures of V2.0 printed in smoke resin at 50 micron:

[Christopher72]

Well done. You have improved on the OEM fit of the concept. My recommendation (worth price charged), is to stay away from ABS and go ASA if you are intent on that route - a much better alternative. Although if you are intending to match the piano black gloss, then why not print in nylon? You can prime, color, and gloss coat that, and while you're at it, polish the scratches out of the center trim as well. Would look factory.

[Hejnfelt]

That’s an excellent suggestion on the material. I’m not really going for a gloss black look particularly, just something that “blends in” to the stock look.

I’ve never worked with ASA so it didn’t cross my mind. The small sacrifice in impact strength is worth all the other properties it has and seems my printer should handle it! I’ll definitely print a test in that but in general it seems to go straight to the top of the list of materials.

[AnubisZed]

I was amazed how little response the idea got to be honest. Owners are constantly banging on about cup holders in the E89, or rather the lack of them, then when someone produces them there is little to no response
Now we have two, very similar designs to choose from.
I did talk to Lars about the idea of a central slit for things like phones etc, and he did produce a 3D drawing so one was ready to put into practice, and I thought he was going to put it up o his website as an option.
I've still got mine in place and is, for the lost part, carrying my dashcam button and shopping trolley coin as it not been used for long trips yet so no drinks have been in it recently.

Hejnfelt, do you have any photos showing how it's fitted from underneath?

[Christopher72]

BMW used 3D printing to restore Elvis' 507 roadster, so you're in good company. [https://www.bmw.com/en/automotive-life/ ... elvis.html]

[Hummingbird13]

Great concept and execution! Get it out on the other forums and Facebook and the interest will come. You’re looking at a very small niche market, so you won’t retire on it, but it’s still a desirable item. Let me know when you finalize things and I’ll be happier to order one or more. (I’d sell them at meets around here).

[Mikopop]

Hi

Great job, would be interested in this so long as it doesn't obstruct the manual gear stick, have you tried the prototype in a manual?

[Hejnfelt]

I was amazed how little response the idea got to be honest. Owners are constantly banging on about cup holders in the E89, or rather the lack of them, then when someone produces them there is little to no response
Now we have two, very similar designs to choose from.
I did talk to Lars about the idea of a central slit for things like phones etc, and he did produce a 3D drawing so one was ready to put into practice, and I thought he was going to put it up o his website as an option.
I've still got mine in place and is, for the lost part, carrying my dashcam button and shopping trolley coin as it not been used for long trips yet so no drinks have been in it recently.

Hejnfelt, do you have any photos showing how it's fitted from underneath?

I use the 4 retention screws that both the cointray and ashtray use. I didn't take photos of it, but you can see the underside of the model in the attached photo. Keep in mind this is V2.0 and V3.0 will offer small changes that together make a big advantage.

IMG_6378.JPG (40.04 KiB) Viewed 934 times

Also, I didn't just model this up from scratch... Well I did, but in order to get the exact dimensions, I used Photogrammetry to re-create a submillimeter precise model of the OEM cointray out of my car taking about 300 61Megapixel high res photos from various angles and stitch them together into a useable 3D model. I used this 3D model to evaluate the dimensions of the quite complex centering geometry of the edge lip retention flanges.

Blender screenshot.png (322.06 KiB) Viewed 934 times

Blender screenshot 2.png (425.58 KiB) Viewed 934 times

BMW used 3D printing to restore Elvis' 507 roadster, so you're in good company. [https://www.bmw.com/en/automotive-life/ ... elvis.html]

Nice

Great concept and execution! Get it out on the other forums and Facebook and the interest will come. You’re looking at a very small niche market, so you won’t retire on it, but it’s still a desirable item. Let me know when you finalize things and I’ll be happier to order one or more. (I’d sell them at meets around here).

Definitely not looking to retire on this haha but if you have some suggestions of specific forums where you believe this might find traction I'm all ears. I did share it on Zpost too. I didn't really do this for the money which is also why I'm willing to sell these pretty cheap. 3D printing will always be wildly more expensive than a mass produced injection molded part and this is especially true when working with exotic materials and environments that require temperature, moisture, UV and chemical stability. These constraints is what attracted me to this project as such a space will come into so many different materials from the grease on your fingers and get very hot (coffee in paper cup) and also need to withstand standing outside in winter -20C and not absorb moisture from condensation on drinks and not react when in contact with various metals from coins to alu cans... It's just a fun project to learn a lot and at the same time upgrade the functionality of this vehicle which outside the cupholders under the armrest is really a well put together machine.

[Hejnfelt]

Hi

Great job, would be interested in this so long as it doesn't obstruct the manual gear stick, have you tried the prototype in a manual?

Thanks! I have not tried it in a manual, but obstruction will be fairly similar to what you can see in AnubisZed's video on the other drinks holder that just released. Watch the gear stick part here: https://youtu.be/m7XNth61FfI?t=246

THe main difference will be that for V3.0 I am spacing the cylinders further apart to create more room for the gear lever and also make it easier to reach the roof button. It's obviously not large distances, but every little bit matters in this

[Marcoose]

Adding my own two cents ... it would be elegant to preserve the ashtray lid.

Otherwise, kudos for the technical skills. Any chance you could use those skills to make extended paddle shifters ?

[DonDon]

Excellent work indeed. Just a question for you - I see that your iDrive controller is on the wrong side - does the cupholder need to be any different for RHD cars?

[AnubisZed]

Excellent work indeed. Just a question for you - I see that your iDrive controller is on the wrong side - does the cupholder need to be any different for RHD cars?

[Nictrix]

Adding my own two cents ... it would be elegant to preserve the ashtray lid.

I said this before but apparently there is not enough space for a cup/bottle to fit through the gap if the Ash tray lid is still in use.
It would also take quite a bit more work as the lid is attached to the ashtray and not the centre console.
Can't see many people who have the ashtray lid swapping it out for something without a lid though.

[Hejnfelt]

Adding my own two cents ... it would be elegant to preserve the ashtray lid.

Otherwise, kudos for the technical skills. Any chance you could use those skills to make extended paddle shifters ?

I'm afraid the ashtray lid stows within the space and you would need at least 15mm of valuable space to keep it which would result in no regular cups fitting in the leftover space. Unfortunately the space is so far forward that keeping it as a flip up lid also isn't possible due to the lower stereo dashboard getting in the way.

I would imagine paddle shifters can easily be bought on AliExpress, no?

[Hejnfelt]

Adding my own two cents ... it would be elegant to preserve the ashtray lid.

I said this before but apparently there is not enough space for a cup/bottle to fit through the gap if the Ash tray lid is still in use.
It would also take quite a bit more work as the lid is attached to the ashtray and not the centre console.
Can't see many people who have the ashtray lid swapping it out for something without a lid though.

Indeed, this is correct.