Gadget Freak

This Gadget Freak entry contains instructions for building a martini blender out of junk parts.

The Beginning

The whole thing started out as a conversation between my good friend Ken and I. We were talking about the first gas-powered blender I had seen. I was showing him some pictures of it from an ad I had seen on the web. As soon as he saw it he said, “Dude, we could build that.” I responded with, “Dude, I’ve got an old string trimmer engine at home in the shed.”

And that was all it took.

The first version was not nearly what it is today. It started off very simple - an engine and some adapters to get it coupled to the blender jar, and then screwed it to a small piece of Formica I had with some conduit clamps and that was it. The top fuel blender was born.

Above: The original top fuel blender

Top fuel blender schematic
Motor tach driver circuit schematic

Three years later, and the current version is almost entirely made of polished billet aluminum. The drive output and adapters, motor hold-down clamp, fuel cell, pitcher base, throttle handle, exhaust adapter, base feet, K&N air cleaner adapter, pull start rope handle, carburetor switch block, “Christmas tree” riser, and the base plate were all custom machined. It fits right in at the pits at the race track, and is loud enough (Thanks to a tunable exhaust) to compete with the cars!

The tachometer is a standard 10,000 RPM race ready model with a shift light from SunPro. Other purchased non-electronic components include the rubber vibration isolators, the 2 handles, stainless steel pitcher, and the various stainless steel fasteners.

Motor Operation

The motor starts and runs just like a normal string trimmer would, however with the addition of a 3 pole switch in the base, you can select “Off” to kill everything, “Run” to just let the motor run, or “Tach” to run the motor and have the tachometer display actual RPM. The stock choke lever has been retained for starting purposes. The main difference is the additional carburetor and fuel cell setup that can be swapped for running an alcohol and nitromethane fuel blend – Race track only. Not for home use!

Tree Operation:

The “Christmas Tree” is totally separate – It has a power switch on the display box to power it on, and is then tied into three other switches. The first is directly below the display and selects either Sportsman Class Racing or Pro Class operation. The second is mounted to a billet aluminum block above the carburetor and is operated by the throttle linkage. When the throttle is pulled the switch signals the timer for your reaction time. The third switch is in the throttle handle and is for resetting the tree.

The tree works just like a normal drag racing tree. The reset switch will light the pre-stage LED’s and then a random timing circuit (1-5 seconds) will light the stage LED’s. At that point the start lights sequence will start.

The start light circuit is programmed to function either as a Sportsman (three sequential flashes of the amber lights) or Pro (one simultaneous flash of all three amber lights) depending on the position of the selector switch. At the end of the light sequence, the reaction timer is started and the green light is illuminated. The timer then waits for a pull of the throttle which triggers the carburetor switch and stops the timer.

The other scenario is that if the trigger is pulled to quick and you receive “False Start” displayed on the VFD and a red light illuminated. However, assuming your reaction time is valid (Between 0 and 1 second) it will be displayed on the VFD. If the reaction time is between 1 and 2 seconds your reaction time will be displayed as “YOU’RE DRUNK” and if it is longer than 2 seconds it will be displayed as “YOU SUCK”… Sorry, but if you’re that bad it’s time to lay off the sauce.

Other components

ND 610 PS2506-4 NEC IC 16 pin op amp
ND 543 PS2506-4 NEC IC 16 pin op amp
16F84-10/P 0137HTE PIC 8 bit MCU 1KX14 flash 10MHz (18)