Summary: If you are the owner of a Taotronics car phone holder and, like me, you like the design and functionality it provides, but dislike suction cup attachments in general and the fact that it occassionally falls off the windscreen when the weather is warm, then check out this project where I convert the suction cup mount into a permanent mount for my car’s dashboard. Super-steady and no more messing around with the unpredicatbility of suction cups. Looks good too, although would have preferred it in black!
Background
(Image from Amazon product page)
I have the Taotronics car phone holder (picture on the left) that I use to hold my Navigon GPS on the windscreen of my car while driving. Although the holder is an excellent piece of kit, as with almost every other car windscreen suction-mounted device, it does occasionally fall off the windscreen (especially when the weather is hot). So it was really begging for some sort of permanent mount to the car’s dashboard. I should emphasise at this point that the current model of Taotronics car phone holder (I have the earlier version which looks identical) that you can buy off Amazon today is claimed to have an improved 
suction cup design (I have not tested it personally) so you may be completely happy with the performance of their latest iteration. However, if you are experiencing similar issues with the newer version or you just prefer not to have it stuck to your windscreen then, as far as I can tell from the pictures, the key parts of the new version of the holder that are relevant to the permanent mount adapter desribed here remain unchanged from the original version and so should be just as applicable to the newer version.
Ok, so what were the requirements? The Taotronics holder needed to be strongly attached to the dashboard so that there would be no chance of it falling off again especially as I have a tendency to remove the GPS from the holder with one hand which probably puts extra strain on the attachment to the car anyway. The holder also needed to be fixed firmly so that there would be no jiggling about during driving and it needed to withstand the usual vibrations from driving over the long term so it would not be necessary to revisit this issue again. Pretty straightforward!
Methods
Disassembled
My preferred way to permanently attach things together is to use nuts and bolts or machine screws, and so a simple solution might have been to simply drill a couple of holes in the base of the Taotronics holder and attach it to the car dashboard that way. Unfortunately, there was no obvious way to drill into the base of the holder due to its curved design, and there was even a good chance that it would crack under the uneven pressure of the drill bit. So after much deliberation, I reluctantly decided that the good old 3D printer was required to make an attachment adapter.
The holder itself was first disassembled as shown in the picture (right). The suction cup was detached by partially pushing the steel pin out of the suction cup lever and then prying the lever itself off. This was not all that easy to do and risked damaging the lever (although it did end up being fine when it did eventually com off), however, the lever was not to be needed again so had it broken, it would not have been a problem. Importantly though, the internal parts of the suction cup where the steel pin goes through the suction cup protrusion needed to remain intact as this was to be used later for attaching the permanent mount adapter.
3D print with suction cup inserted
The 3D adapter was modelled in Blender (free software from www.blender.org) and designed to incorporate the original suction cup and its plastic protrusion to hold the 3D-printed adapter in place under the body of the Taotronics phone holder. Four machine screws were designed into the 3D model to bolt the whole thing down to the car’s dashboard. The 3D part was printed out on a Velleman K8200 using 3mm PLA filament (before you wonder, pink filament was on sale!) with the support material option turned on so that the cavity for the suction cup would be well formed.
The small tab on the suction cup that is normally used to remove it from a windscreen was cut off (see bottom left of the Disassembled picture above) and the cup itself was inserted into the 3D print so that its original top protrusion poked out through the top of the adapter. This then re-seated itself back into the body of the Taotronics holder in a similar way to how it was originally designed. An M3 x 20 machine screw and lock nut were used to secure it firmly in place, which in turn ensured that the 3D-printed adapter was securely fixed to the car phone holder body.
For attachment to the dashboard, 5mm holes were drilled into the part of the car dashboard that had been previously removed from the car. Fortunately my Smart Roadster
(picture right) comes apart like a Meccano set (:)), so it was a doddle to remove the part of the dashboard where I decided the Navigon GPS would be best placed – ie right in the centre between myself and the passenger seat. Why there? Well, having been on several trips out of town, I felt it was important for the GPS to be accessible from the passenger side as well as from the driver’s side. This was because, on several occasions, an on-the-go change of route was called for while driving, and it was just so much more efficient to have the passenger sort that out on the GPS rather than for me to have to stop driving and re-route 
it myself (I’m not the multi-tasking type!). Fortunately the Taotronics holder has adequate degrees of swivel to be able to be positioned facing the driver’s side even when fixed to the centre of the dashboard. Anyway, a 5mm drill bit on a pillar drill was used to make the four holes in the plastic dashboard part and the whole car phone holder and mount were attached with four M5 x 12 machine screws, M5 penny washers and locknuts from Toolstation. Note the use of nylon locknuts, which are necessary to prevent the nuts coming loose from the usual vibrations of driving.
File Download
Materials
| Taotronics phone / GPS holder hardware | Component | Quantity | ||
|---|---|---|---|---|
| Taotronics car phone holder |  | 1 | ||
| Machine screw | M3 x 20mm |  | 1 |  |
| M5 x 12mm |  | 4 |  |
|
| Nylon lock nut | M3 |  | 1 | |
| M5 | | 4 | |
|
| Penny washer | M5 |  | 4 | |