Build Thread Littlemotor’s Tekno NB48 2.2 Build Thread! 😈

[Littlemotor]

Excellent man! That's a beautiful build. Blue paste is the stuff! I didn't know that about the steering post pockets. Great details! I do the same thing- digital calipers- check- custom cut stuff.

Thanks brothaman!! It’s coming along! Yepper-been that way on most race grade stuff for a hot minute now.. The Tekno’s just really bring the standard imo!! Glad I’m not the only lunatic that finds themselves reinventing the wheel so they can sleep at night… or during the day..

 

[WickedFog]

Thanks brothaman!! It’s coming along! Yepper-been that way on most race grade stuff for a hot minute now.. The Tekno’s just really bring the standard imo!! Glad I’m not the only lunatic that finds themselves reinventing the wheel so they can sleep at night… or during the day..

You made that build your biyatch last night. Great work, and informative posts. Keep it coming!

 

[332_RC]

Thanks brothaman!! It’s coming along! Yepper-been that way on most race grade stuff for a hot minute now.. The Tekno’s just really bring the standard imo!! Glad I’m not the only lunatic that finds themselves reinventing the wheel so they can sleep at night… or during the day..

Well being a machinist like 0.05" is a mile. Lash or slop= 0.004" drives me nuts. It CAN be fixed. I work down to 0.0001" a lot no problem. 0.002" is a yawning festival.

 

[WickedFog]

Well being a machinist like 0.05" is a mile. Lash or slop= 0.004" drives me nuts. It CAN be fixed. I work down to 0.0001" a lot no problem. 0.002" is a yawning festival.

We had a line of oil filter bypasses we made for NASCAR. The bore for the valve was +.0002"/-.0000". First part in the morning after the machine sat all night would come out dead nuts. That always got me in the feels. How a cheap ass Haas could do that baffled me. But my little VF2 was dialed in and a wicked little mill. I so miss all that fun stuff. Littlemotor was a fellow metal chip maker. And it shows in his OCD inflicted build threads like this one

 

[332_RC]

Yes it does!

 

[332_RC]

@Littlemotor I have a question when you can. I've studied along with this build. Seeing all the components & tech you've done, I've learned alot. All top notch. I see the servo is mounted longways like a few Arrma models have their servos mounted. My Talion chassis is the same. Stock, it's mounted with the spline horn closest to the bellcrank link/steering arm. I've noticed on your build, & a few others online while searching, it's mounted with the horn at the center diff. The connector link will be longer. I've mounted my servo on the Talion with the horn at the diff. I made a long custom HD adjustable link. I read that doing this creates more precise steering, although I've also read it lessens servo arm throw effectiveness, making it less precise & the full sweep of the servo is not utilized. If you can, explain the difference. Mount positioning & link length, geometry, & any differences in each, if any.
Thanks bro! Sick awesome build here

This is my Talion. Above is yours.

 

[WickedFog]

Having the servo gear farther away from the bellcrank attachment point means your connecting rod will have less deviation from being parallel to the chassis centerline.

The way my mind always analyses things like this is take it to the extreme. Lets say your servo is a mile away from your bellcrank. The servo horn rotating is not going to show much of an angle change on that connecting rod at all.

Now move the servo right next to the bell crank. As the rod connection at the servo horn travels along its arc, that connecting rod is going to change angles drastically.

The ideal setup for a steering servo would be a linear actuator, eliminating the arc the horn travels completely. Because as the horn leaves center, the distance it pulls that rod exponentially decreases until it reaches 90° rotation, where there is zero pull on the rod. Any angle your rod deviates from parallel amplifies that decreasing value.

 

[jimdavis577]

Having the servo gear farther away from the bellcrank attachment point means your connecting rod will have less deviation from being parallel to the chassis centerline.

The way my mind always analyses things like this is take it to the extreme. Lets say your servo is a mile away from your bellcrank. The servo horn rotating is not going to show much of an angle change on that connecting rod at all.

Now move the servo right next to the bell crank. As the rod connection at the servo horn travels along its arc, that connecting rod is going to change angles drastically.

The ideal setup for a steering servo would be a linear actuator, eliminating the arc the horn travels completely. Because as the horn leaves center, the distance it pulls that rod exponentially decreases until it reaches 90° rotation, where there is zero pull on the rod. Any angle your rod deviates from parallel amplifies that decreasing value.

another way of putting it, would be like a piston in the motor. At BDC and TDC the relative turn of the crank shaft has little effect on the travel of the piston in relation to the amount of travel the crank turns. However on the compression and exhaust stroke the same amount of travel in the crankshaft equates to a lot more movement of the piston in that portion of the rotation.

At least that's how i see/ correlate the movement ...

 

[Littlemotor]

View attachment 215029

You made that build your biyatch last night. Great work, and informative posts. Keep it coming!

Thanks killah!!! I’m just tryin’ to keep up with you over there!!

 

[332_RC]

Having the servo gear farther away from the bellcrank attachment point means your connecting rod will have less deviation from being parallel to the chassis centerline.

The way my mind always analyses things like this is take it to the extreme. Lets say your servo is a mile away from your bellcrank. The servo horn rotating is not going to show much of an angle change on that connecting rod at all.

Now move the servo right next to the bell crank. As the rod connection at the servo horn travels along its arc, that connecting rod is going to change angles drastically.

The ideal setup for a steering servo would be a linear actuator, eliminating the arc the horn travels completely. Because as the horn leaves center, the distance it pulls that rod exponentially decreases until it reaches 90° rotation, where there is zero pull on the rod. Any angle your rod deviates from parallel amplifies that decreasing value.

another way of putting it, would be like a piston in the motor. At BDC and TDC the relative turn of the crank shaft has little effect on the travel of the piston in relation to the amount of travel the crank turns. However on the compression and exhaust stroke the same amount of travel in the crankshaft equates to a lot more movement of the piston in that portion of the rotation.

At least that's how i see/ correlate the movement ...

Thank guys. I made a post about it- didn't want to derail this feature.

 

[Littlemotor]

We had a line of oil filter bypasses we made for NASCAR. The bore for the valve was +.0002"/-.0000". First part in the morning after the machine sat all night would come out dead nuts. That always got me in the feels. How a cheap ass Haas could do that baffled me. But my little VF2 was dialed in and a wicked little mill. I so miss all that fun stuff. Littlemotor was a fellow metal chip maker. And it shows in his OCD inflicted build threads like this one

You are a madman with the stuff you’ve done over the years for sure. I seriously appreciate the support, and props-but I f’d up my opportunity to get into tool & die in true punk asss kid fashion, when it was literally handed to me on a silver platter.. I’m just the poor mook that loves OT more than you and @332_RC , and maintains those Haas, OKUMA, EMagg, etc., assets, so that you guys can make the chips.. I know my way around them, as you can’t fix them, calibrate, compensate, setup, etc, withOUT those skills-but Y’ALL are the true Jedi Mastuh’s around here..

 

[Littlemotor]

Having the servo gear farther away from the bellcrank attachment point means your connecting rod will have less deviation from being parallel to the chassis centerline.

The way my mind always analyses things like this is take it to the extreme. Lets say your servo is a mile away from your bellcrank. The servo horn rotating is not going to show much of an angle change on that connecting rod at all.

Now move the servo right next to the bell crank. As the rod connection at the servo horn travels along its arc, that connecting rod is going to change angles drastically.

The ideal setup for a steering servo would be a linear actuator, eliminating the arc the horn travels completely. Because as the horn leaves center, the distance it pulls that rod exponentially decreases until it reaches 90° rotation, where there is zero pull on the rod. Any angle your rod deviates from parallel amplifies that decreasing value.

The way I’ve been doing it, and was learnt was that while yes; there can be deflection (as NOTHING on this planet is 100% efficient), but so long as your centerline of the mechanical master, and slave are the same, and the distance from that centerline to the mechanical connection; IE-the servo saver hole position, and the servo HORN hole position) are equidistant from said centerline, then as long as the servo HORN is properly “clocked” to be parallel with the servo ARM, then your arc will be the same, and therefor correct.

As I read your reply-this is roughly how I interpreted your logic to be as well. Math is a wonderful thing. -and that’s all hotrods, racecars, and silly toy cars are; MATH.

another way of putting it, would be like a piston in the motor. At BDC and TDC the relative turn of the crank shaft has little effect on the travel of the piston in relation to the amount of travel the crank turns. However on the compression and exhaust stroke the same amount of travel in the crankshaft equates to a lot more movement of the piston in that portion of the rotation.

At least that's how i see/ correlate the movement ...

This is referred to as “dwell”.

Nope-I read through that too quickly. You’re talking about mechanical advantage based on rotational motion/ratio. My fault. Obviously “dwell” is the portion of that where the crank is still rotating, but the piston doesn’t move (much) during a few degrees of that-and only happens at TDC, and BDC.. That’s my fault.

 

[Littlemotor]

@332_RC

I should mention that I cannot STAND how Arrma does this. They do it in order to utilize a single non-adjustable steering link across the board to work with literally ALL of their vehicles (more or less-within the same scale platforms at any rate).

The problem with this is that when you cannot achieve what @WickedFog, @jimdavis577 , and myself are talking about mechanically due to servo spline count, or that there’s a minute difference in those measurements, your vehicle will ALWAYS have more throw to one side than the other; mechanically speaking. It’s a piss-poor way of doing it imho. If I were doing your caliber build on an Arrma, I’d have done the exact same thing you are doing. Much better way of setting it up IMO.

 

[332_RC]

@332_RC

I should mention that I cannot STAND how Arrma does this. They do it in order to utilize a single non-adjustable steering link across the board to work with literally ALL of their vehicles (more or less-within the same scale platforms at any rate).

The problem with this is that when you cannot achieve what @WickedFog, @jimdavis577 , and myself are talking about mechanically due to servo spline count, or that there’s a minute difference in those measurements, your vehicle will ALWAYS have more throw to one side than the other; mechanically speaking. It’s a piss-poor way of doing it imho. If I were doing your caliber build on an Arrma, I’d have done the exact same thing you are doing. Much better way of setting it up IMO.

Thanks & that's been an issue building my Arrma rigs. All my 6s bashers have adjustable links & custom end points to achieve proper L & R full throw steering. I even clearance the bulkheads for more. Right to the very point the knuckles are in the pillow ball spheres & rod, still no bind or hyperextension of the steering turnbuckles.

 

[Littlemotor]

Thanks & that's been an issue building my Arrma rigs. All my 6s bashers have adjustable links & custom end points to achieve proper L & R full throw steering. I even clearance the bulkheads for more. Right to the very point the knuckles are in the pillow ball spheres & rod, still no bind or hyperextension of the steering turnbuckles.

As long as they’re parallel (by centerline, and link length) and the servo horn throw (dictated by hole position at servo horn) matches the servo saver arm throw are the same, you’re golden. Otherwise for this application-it doesn’t matter where in space the servo is, nor the servo saver, as long as you are able to achieve those things above.

 

[332_RC]

As long as they’re parallel (by centerline, and link length) and the servo horn throw (dictated by hole position at servo horn) matches the servo saver arm throw are the same, you’re golden. Otherwise for this application-it doesn’t matter where in space the servo is, nor the servo saver, as long as you are able to achieve those things above.

You tha man! Thanks brother!

 

[Littlemotor]

You tha man! Thanks brother!

No problem homie-anytime! Glad to help!

 

[Doom!]

You guys make my brain hurt, I don't math good. I can make pretty pictures though.

 

[CertifiedMike]

You guys make my brain hurt, I don't math good. I can make pretty pictures though.

Its not us... stop using your forehead to type numbers!!!
Those 'pictures' you 'make' are only in your head! Like when you see stars after a good knock on the dome!

 

[Doom!]

Well the pretty colors do smell good.