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Hello. I've been following this group for a while. I fancy the Citizen Kane's Hammond light DIY and decided to do a mod. I will share some mechanical and electronic drawings with you. Keep in mind this is my first time using a 3D CAD software (Google Sketchup). There's alot of experienced mechanics in here for sure! Please tell me what you think. I'll provide many images of the 3D model with text in them (don't worry, they are small sized files for fast loading). I'm not english speeking person also, please excuse my english. Ok enough excuses..
Wow. This has been a steep learning curve. Watching youtube videos on how to draw 3D with Sketchup has helped designing alot. Its much easier to see how things fit together now. A 3D model of the Hammond box is available for download at hammonds website. I've used a plugin for Sketchup to convert from "iges"- to "skp"-files. I notice that "iges" 3D model files are the ones mostly available (for example at molex.com and hammond mfg among many). The STAR LED model was downloaded from Google 3D warehouse. A big thanks to the designer of this model. Maybe you are at this forum aswell.
Features
The features that makes this DIY a bit different than the others are:
- Integrated battery.
- Thermostat with dual tresholds (one for warning led, and the other for cutting the current at overheating).
- Pot-meter, sealed with pass-through rubber grommet on the pots axel. (see images).
- On/Off switch in pot-meter.
- Optional 8pin/8bit flash-based Microcontroller + mode-button. (create pcb footprint for soldering a microcontroller to the pcb for future firmware project).
Images of 3D Model
Front
Rear
The LED is for high-temp warning. The design may need a charging connector, or maybe ill just unscrew the cover to charge it.
External Contents
Internal Contents (Side View)
For the 4 SSC P4 i'm thinking a 4S1P 2600mAh Li-ion pack would do giving plenty of runtime (3h+) and enough voltage. A flat arangement of the four sels fit neatly inside the enclosure together with the leds. Battery mount-plate not yet designed.
I've been researching the forum for waterproof potentiometer, and such a part is not available. A rubber grommet with 6mm inner dia that match the
pot's axel diameter will hopefully keep water out of the case and the same time make rotation possible. Has anyone tested this?
So why the @£!# do one need a thermostat in this. Usually one just design for an operating temperature range, one would do alot of testing to ensure the light performance in that range. 1st of all, its just for safety and for variety (=funn). The LM56 is quite clever. It does all the analoge noise sensitive operations on its die and producing a digital cmos (open collector) output about the state of the thermostats. It has two thermostats that give four states. In other words its possible to monitor two thresholds. That gives many application uses. For this application i want the first threshold to be the point where a warning led is switched on (lets say at 50C), and the second threshold where the power is cut to protect the battery pack and LEDs (lets say at 60C). The thresholds are configured using three resistors (see datasheet for details).
(EDIT: image replaced. Previous image noted 4P1S which was wrong)
Thermostat Assy
This is the LM56 device with R0603 resistors mounted on it. Values will be calculated later. The datasheet note that the temperatyre is measured at the package-pins. To electrically insulate it from the L-profile-LED-mount (see image above), and conduct heat to it, it will be dunked in thermal glue and then glued to the rear of the profile, close to one of the LEDS.
PCB Assy as seen from top
The PCB is slided into the Hammond box's PCB-groves. The box is for 100mm wide PCBs and upto 2mm thick. Neat! The PCB connects battery pack, LEDs, driver, Pot, switch, and thermostat. The datasheet for the LM56 thermostat has loads of application notes. The same goes for the 3021E. More on that later when i post electronic schematics.
For the thermostats digital cmos output, signalling high and low will override the pot-meter outputs to the Ref input of the 3021E Buckpuck (datasheet). Can be somehow be interfaced with the led driver by connecting it to a pnp transistor that has been connected in parallel with the thermostat.
The mechanical drawing showing hole positions etc will be generated using sketchup. There will be a challenge to get all the mounting holes and component placement aligned with the pcb-layout. I'm currently using Eagle. How do you do this transition from 3D cad to pcb-layout?
Rear view again, without rear bezel
Thanks for reading and for future comments. I really love it.
Wow. This has been a steep learning curve. Watching youtube videos on how to draw 3D with Sketchup has helped designing alot. Its much easier to see how things fit together now. A 3D model of the Hammond box is available for download at hammonds website. I've used a plugin for Sketchup to convert from "iges"- to "skp"-files. I notice that "iges" 3D model files are the ones mostly available (for example at molex.com and hammond mfg among many). The STAR LED model was downloaded from Google 3D warehouse. A big thanks to the designer of this model. Maybe you are at this forum aswell.
Features
The features that makes this DIY a bit different than the others are:
- Integrated battery.
- Thermostat with dual tresholds (one for warning led, and the other for cutting the current at overheating).
- Pot-meter, sealed with pass-through rubber grommet on the pots axel. (see images).
- On/Off switch in pot-meter.
- Optional 8pin/8bit flash-based Microcontroller + mode-button. (create pcb footprint for soldering a microcontroller to the pcb for future firmware project).
Images of 3D Model
Front

Rear
The LED is for high-temp warning. The design may need a charging connector, or maybe ill just unscrew the cover to charge it.

External Contents

Internal Contents (Side View)
For the 4 SSC P4 i'm thinking a 4S1P 2600mAh Li-ion pack would do giving plenty of runtime (3h+) and enough voltage. A flat arangement of the four sels fit neatly inside the enclosure together with the leds. Battery mount-plate not yet designed.
I've been researching the forum for waterproof potentiometer, and such a part is not available. A rubber grommet with 6mm inner dia that match the
pot's axel diameter will hopefully keep water out of the case and the same time make rotation possible. Has anyone tested this?
So why the @£!# do one need a thermostat in this. Usually one just design for an operating temperature range, one would do alot of testing to ensure the light performance in that range. 1st of all, its just for safety and for variety (=funn). The LM56 is quite clever. It does all the analoge noise sensitive operations on its die and producing a digital cmos (open collector) output about the state of the thermostats. It has two thermostats that give four states. In other words its possible to monitor two thresholds. That gives many application uses. For this application i want the first threshold to be the point where a warning led is switched on (lets say at 50C), and the second threshold where the power is cut to protect the battery pack and LEDs (lets say at 60C). The thresholds are configured using three resistors (see datasheet for details).
(EDIT: image replaced. Previous image noted 4P1S which was wrong)

Thermostat Assy
This is the LM56 device with R0603 resistors mounted on it. Values will be calculated later. The datasheet note that the temperatyre is measured at the package-pins. To electrically insulate it from the L-profile-LED-mount (see image above), and conduct heat to it, it will be dunked in thermal glue and then glued to the rear of the profile, close to one of the LEDS.

PCB Assy as seen from top
The PCB is slided into the Hammond box's PCB-groves. The box is for 100mm wide PCBs and upto 2mm thick. Neat! The PCB connects battery pack, LEDs, driver, Pot, switch, and thermostat. The datasheet for the LM56 thermostat has loads of application notes. The same goes for the 3021E. More on that later when i post electronic schematics.
For the thermostats digital cmos output, signalling high and low will override the pot-meter outputs to the Ref input of the 3021E Buckpuck (datasheet). Can be somehow be interfaced with the led driver by connecting it to a pnp transistor that has been connected in parallel with the thermostat.
The mechanical drawing showing hole positions etc will be generated using sketchup. There will be a challenge to get all the mounting holes and component placement aligned with the pcb-layout. I'm currently using Eagle. How do you do this transition from 3D cad to pcb-layout?

Rear view again, without rear bezel

Thanks for reading and for future comments. I really love it.