# T-jet Dyno



## super8man (Jan 29, 2013)

Fun fun fun!!! This car read about 0.15v at its highest...it jumps around a bit.


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## slotking (May 27, 2008)

cool

I started to make 1 a long time ago, ended just buying 1

good to see people with talent

is there a tire the car rides on on the driver side?


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## Hornet (Dec 1, 2005)

Looks good Super.

Are you a transplanted Canuck
Rick


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## super8man (Jan 29, 2013)

Just a single tire the car rides on...I suppose it could use a dummy on the other side.

And yes, transplanted!


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## sidejobjon (Jun 3, 2010)

Superman 8,
Is there directions to build this? Looks like i understand left side But whats in box & what are the resistors for??
Thanks SJJ


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## Hornet (Dec 1, 2005)

If you add another slave motor to the other side of it,tie into the electrical leads from it,and put it on a 25 ohm or higher pot, then you'll have an adjustable load motor.
Just my 02 from building a few slave dyno's.

The Canuck flag sticks out pretty good,where abouts did you transplant from:wave:
Rick


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## sidejobjon (Jun 3, 2010)

Hornet,
Whats that on right?
Thanks SJJ


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## bearsox (Apr 22, 2006)

super8man said:


> ...I suppose it could use a dummy on the other side.


*I am NOT available so you will need to find another dummy !!! LOL ! *

*Nice work , Bear :wave:*

*For more info just ask that idiot Parts Pig ...he thinks he knows everything about everything and NEVER minds telling ya your wrong and he's right ! :wave:*


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## Hornet (Dec 1, 2005)

SJJ,i'm only guessing at what's under the cover,but it looks like it's a set of diodes,not resistors,and a small cap,to probably smooth out the power to the car,or to smooth out the slave motor voltage reading.
I'm guessing again,but i'm thinking they are there so if you hook it up to power in reverse it won't backfeed itself and blow something up.
Diodes only flow power in one direction.
I'm only guessing,as it's hard to tell by the pic,what all's under the cover,and what everything does,but that's my un-educated guess,lol

Super,this tip is from Boosted and it works,add a couple small neo magnets to the outside of your can motor,it'll give you slightly higher voltage output readings,and supplies a bit more load to the system.

If you do add another slave motor to the opposite side and tie it to a pot,install a cheap on/off toggle switch in one of the leads to the pot,so you can turn the pot off and take load off the extra slave,every once inawhile it's nice to be able to switch the extra load motor completely off 

If any of you guys are attempting to build yourself a slave motor dyno,and you want to do Amp draws at the sime time,it doesn't hurt to solder a small 0.1 ceramic disc capacitator across your power rails.
When there's power flowing through the rails,they can act like the rabbit ears on your old T.V sets,and generate a pile of RF interferance,that can cause a cheap amp meter or multi-meter to not read properly.
Learned that one the hard way,lol
Rick


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## sidejobjon (Jun 3, 2010)

I will start getting parts togeather, Is the slave motor a 1/24 scale motor to start with. Thanks for information. Keep it coming.
SJJ


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## super8man (Jan 29, 2013)

Good ideas in here. I just got back from the Fray in Ferndale and saw some pretty sophisticated dynos. As for the blackbox, yes, they are diodes which appear to "shape" the power and a resistor to run the LED. The flickers when driving a car motor. I like the idea of a second motor on the driver side along with the concept of applying a load. Interesting.


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## Hornet (Dec 1, 2005)

One thing i do on my slave motor dynos is i back the car into the driven tires,and use a spring loaded pen contraption to keep the car pressed up against the tires.

Here's a link to a pic of my old slave dyno.

I use industrial strength rails,lol

Rick

http://routedtracks.yuku.com/topic/29/Homemade-Dyno


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## Boosted-Z71 (Nov 26, 2007)

Just wanted to post a pic of my HO dyno, I added the digital panel meters. It will read, Track Input voltage, amp draw, slave motor output voltage, as well as hook up to the computer and use the Simple Dyno software for all sorts of neat fun. The power supply is a 20v-5 amp laptop brick, and I have made it adjustable from 3.0 volts to 20 so you can also use it as a break-in box. I added a cooling fan under the car under the car to dissipate heat & the rollers have been balanced. 

Boosted


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## Boosted-Z71 (Nov 26, 2007)

Sorry Wrong picture in previous thread 

This is the latest, will try to get a short video posted tomorrow

Boosted


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## super8man (Jan 29, 2013)

I want that!! Nice job! Actually, I would like to make that myself. Any chance on parts list and schematics?


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## Boosted-Z71 (Nov 26, 2007)

Thanks Super8man, The parts are easy, it starts out as a Tamayia Speed checker for RC cars. To make it into a HO dyno it turns into a very heavily modified Tamayia speed checker / dyno. 

The work, is machining out the area for the rollers, removing and adding a bearing support post for the main roller shaft in a different location, relocating the original electronics optical sensor mechanism, milling the entire top surface of the dyno top so the HO track sits at the proper level for the rollers. The rollers have to be trued and balanced as a shaft assembly, or the car will wiggle somewhat on the rollers (they are awful from the factory) Cut the opening from the track for the rollers, mount the track to the top plate, 

There is also some additional cutting of shafts, re positioning of gears, you need to make the bracket to add the slave motor assembly, (I do have a scan of the bracket, makes an easy cut & fold). You will also need to shim some gears and the rollers to eliminate end play and adjust gear mesh accordingly

Then you get to the wiring, the panel meters came from E-bay, the project box is Radio shack, you will need a power supply, I chose a laptop brick, you need as clean of power as you can get, or the cars heat up faster. Several poteintiometers, adding the fan is a trick as well, as it blows up directly on the bottom of the car, so you need to slot the track & cut some inlets in the dyno box to draw air in. 

As for the electrical attached is a schematic, its kinda general but you can get the point. Also you need to add a .1uf cap across the powered rails to eliminate any RF signals the car emits or your digital amp meter will go crazy and read the RF as line voltage (that took a week, with the help of Hornet to figure out what the heck was going on) Only difference in the schematic is I moved the shunt ahead of the controller, but it will work this way as well, the way I have the shunt installed now the amp meter reads total draw across the power supply, If I turn the fan on it increases the load seen in the system by the meter, as per the schematic you only see the load from the car on the meter. You will also need to build some voltage regulators, and the amp meter needs its own power source, I use a 9v battery for it. 

If you have questions I will try to answer them for you, to build one out of a Speed checker is not a simple task, If you want to build one of these you need one in your hands and torn apart first to understand all what needs to be done, there might be an easier way to do this, this was the path I chose.

Boosted


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## Hornet (Dec 1, 2005)

Boy that looks good Jeff.

Hey i think i know that car,lol:thumbsup:

It's giving you a higher reading on slave output then i'm getting,but that's probably due somewhat to the differances in laptop voltages.

I'll attest to the amount of work Jeff does to convert one to a dyno,when he's done it's a work of art.
Thank-you
Rick


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## Boosted-Z71 (Nov 26, 2007)

Yep, that's a borrowed bullet on the dyno, It spins just a true as you could get, night & day difference now that the rollers are balanced, it does not move around at all.

Just wandered on the voltages, going to play a bit tomorrow with the slave and the dremel.

Boosted


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## Hornet (Dec 1, 2005)

You can see alot of the mods Jeff does to them,if you look at the pic's of the one he built for me.
I added an extra fan to mine,in the side of the box that blows across the voltage regulators,but you can see the fan added under the cars,and you can see the ultra trick bracket he fabs up to hold the slave motor,plus the coil bracket he builds and his hand wound coil for the computor pick-up,that's the funny looking little red and white thingy pointing at the rollers,that he glues a mag to,to energize the coil.
I never asked him how many hours it takes him to build one,but it's lots,and i owe him big time.:thumbsup:
Thanks Jeff
Rick


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## Boosted-Z71 (Nov 26, 2007)

Here is a short video of the dyno in action, forgive my video camera skills 






Boosted


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## super8man (Jan 29, 2013)

Thanks for this video. Very informative.


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## whistlersfriend (Nov 26, 2013)

*Question*

Boosted what do you hook the wires to to get a read from the simple dyno software?


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## Boosted-Z71 (Nov 26, 2007)

Whistlersfriend, it is an inductive pickup, I hand wind a coil, and the wires going to the computer microphone port are attached to the coil. On the dyno rollers there is a magnet that causes the signal of the roller moving to transfer to the computer microphone & into the Simple Dyno software.

There are several threads on here about dyno's and several of them have info on my dyno, or if you would like PM me your e-mail addy, I have a PDF with pictures and some explanation of what I did. Like I stated previously you almost have to have one of the Tamaiya speed checkers in your hands, dissembled and then make your plan to build, after you see all the mods needed. 

Boosted


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