Picked up some brass rod..

[240260280]

Hope to find some time this week end to start an e-tube project. 

 

 

  + =

 

 

CO is my lathe hero!!!

 

 

Edited November 1, 2017 by 240260280

[Patcon]

21 minutes ago, 240260280 said:

CO is my late hero!!!

I didn't know he had died!!

[siteunseen]

Is that new toy/lathe?

Congratulations, it looks nice and a lot smaller than the old ones.  I can think of some things I'd like to turn out but most likely cheaper at the belt buckle shop. 

[240260280]

I meant latte hero

[siteunseen]

Lathe, latte, we all like them both. 

Get jacked up on some lattes and turn out some fine emulsion tubes.

[Captain Obvious]

I don't want to go on the cart!

Seriously though...  I'm just a guy with a latte. 

Those diagonal holes aren't gonna be the easiest thing in the world to do. You'll soon be in the market for a milling machine. Slippery slope I tell ya!!

[siteunseen]

9 minutes ago, Captain Obvious said:

Seriously though...  I'm just a guy with a latte. 

 

I'm just a guy with  a toothbrush but Blue makes an awful sweet looking latte. Telecom guy, mechanic and a barista. What's next?

 

[240260280]

CO I am a coward and will go the Dellorto Mikuni/Solex route at first.  No angled holes at first.

           

 

These will be true "E-Tubes" for "empirical" testing. 

Quick and dirty to understand the relation ships between hole locations and tube size.  Once this is mapped then angled holes will be tested.

I plan to make a drilling block that will have guide holes to consistently drill holes in the same location on all tubes.

I may even try to make a Mikuni solution that fits in a Weber's jet well as a second phase.  Some O rings may be all that is needed to keep the fuel in the tube. Have a look above at the tube on the right.

 

 

 

[Captain Obvious]

Haha! So the "E" stands for "empirical"! That's awesome! I never knew that!

Drilling that hole through the center isn't going to be a huge amount of fun either. Sounds simple, but probably won't be as simple as it sounds on paper. They use a special cutting edge geometry for brass that isn't as grabby. You'll know what I'm talking about the first time the bit grabs and spins your chuck in the tailstock.   

You have a set of collets for the lathe? They lend themselves well to this kind of small, high accuracy work. It's nice to be able to work on one end, cut-off, and then spin the part around to work on the other end with pretty good accuracy using just a collet.

And your idea of making a block to help locate the holes is a good one. I do that kind of stuff all the time. I've got so many little special purposed fixtures around here that I've forgotten what some of the old ones were for!

I'm certainly no machinist, but you know how to reach me if you need a sympathetic ear! 

[240260280]

Thanks as always master machinist CO.  I had a quick look and young grasshopper will avoid the problem you mentioned https://www.youtube.com/watch?v=pAngKHIZgyA

 

No collets yet but I foresee them in the future.

 

 

 

[hwyix]

How did this turn out?

[240260280]

Bad pun.

Back burnered for now.  We just tested F2,F11,F16,and F19 eTubes on the same car and the differences are not significant on 45DCOE carbs.

 

@blodi The predominant parameter is the tube diameter and it acts like the main jet by making the carb richer or leaner. F19 gave the best results but a non-tunable part of the a/f curve at the start of the main coming in seems to be due to exhaust tuning. It can probably be tuned with a "torque tuner" (A reflecting point added to the exhaust system). Here is how the same problem occurred on a bike and how it was resolved:

 

Look at how the torquetuner fixed the rich dip between 2500 and 4000 rpm.  It raised it from 12 to 13.

 

http://www.drdyno.com/AIM_2006-06.html

 

 

Here is the device: https://www.tabperformance.com/Reduce-Back-Pressure-Exhaust-s/203.htm

 

It would be needed in the header.