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INJECTOR UPDATE

Posted: Sun Jul 30, 2017 6:38 pm
by AnthonyDuarte
INJECTOR UPDATE

Friends,

This weekend I began testing injector bodies prior to final assembly and notable porosity was discovered in the castings. The cavities are nearly impossible to see with the naked eye, but they are significant enough that proper injector performance would be compromised.

My goal at Eccentric Engineer is to provide only the highest quality products, so it is with both relief and frustration to announce these injectors will be delayed 1-2 months.

With that said, there is silver lining to this cloud. Since new waxes will need to be made, I’m using this as an opportunity to improve on the design of EE’s Standard Injector.

New molds are already being cut that incorporate the boiler delivery into the body casting, eliminating the elbow from the original design. This will make in-service maintenance much easier, and also gives the injector a lower profile.

It pains me greatly to have to postpone the injectors, but in the end you will be getting a much better product.

I appreciate your patience!
Anthony Duarte
Eccentric Engineer
Standard Injector -  Revised Design
Standard Injector - Revised Design

Re: INJECTOR UPDATE

Posted: Sun Jul 30, 2017 6:46 pm
by mattmason
No issues for me. I'm glad you are not rushing the final product. Shows you are dedicated to giving those of us who ordered one (or two) we are going to have a trouble-free experience with them. I stand by my order and will wait for the final product.

Thanks for being a great supplier, Anthony!

Re: INJECTOR UPDATE

Posted: Mon Jul 31, 2017 5:03 pm
by Trainman4602
Hello Anthony
As you certainty are aware of I am making an injector as well. You’re a bit head of me but the reason for this post is to say that I had the same problem with porosity in the casting as well not with the injector but with the safety valve.

I have since gone to making my own castings so I can control the quality and most importantly the porosity.

I always made my own wax patterns and generally sent or delivered them to the so call great foundry.

The problem is in the fact that they most likely do not flux the molten metal, probably use a considerably amount of cut offs from previous castings.

These practices will defiantly cause pin holes in the castings.

They are so minute that they can only be detected by hydro testing.

I’m not sure what Barry did but Emory Ohlenkamp hydro-tested his; in fact he made his own casting as well for this very reason. Quality Control.

Just yesterday I made starter body castings and I used all virgin metal fluxed it as well and did a good skim on the metal before casting.

This method has worked out very well for me. I can also control the delivery as well, not to mention some other advantages.

Re: INJECTOR UPDATE

Posted: Tue Aug 01, 2017 1:00 am
by Harold_V
Speaking from the position of one who used to refine precious metals, primarily karat gold, I can't stress enough the importance of keeping the metal clean--free of oxides. That is the chief reason gold alloy casts with porosity, too, and accounted for a good portion of gold alloy that was submitted for refining. Fluxing, as Dave has advised, is a great way to limit the problem, as is not re-melting the metal, or super heating unnecessarily. Both tend to aggravate the oxide condition.

H

Re: INJECTOR UPDATE

Posted: Tue Aug 01, 2017 1:24 am
by LivingLegend
Dave...

As far as I can recall, Barry didn't hydro the bodies of his injectors. i guess it boiled down to the high quality put out by the foundry he used.... and the foundry Barry used was one of the best.

When Barry produced the first run of fifty Nathan Simplex injectors during the early 1980s, I machined around 90% or so of the parts them. Barry machined all of the cones and probably half of the bodies. That was all manual machining on Barry's chucker and Bridgeport. Barry had not acquired any of his CNC's at that point. I also shot the waxes and cores at Barry's for all of the Nathan's bodies, which were somewhat complex due to their intricate cores, on that first run and was only able to get one good finished wax pattern for every three bodies shot.... And that was with the mold under vacuum. The defective body patterns had voids due to the wax not completely filling the mold. With all that it took to get them, every Nathan body casting Barry received from the foundry on that first production run was as perfect as you can get....

LL

Re: INJECTOR UPDATE

Posted: Tue Aug 01, 2017 3:42 pm
by Fender
Improper degassing of the melt (or absence of degassing) can also cause porosity in the casting.

Re: INJECTOR UPDATE

Posted: Wed Aug 02, 2017 8:13 am
by AnthonyDuarte
Luckily all the machined components are fine. When new castings come in it should be a quick turnaround.

I didn't have enough castings to fill all the orders I received, so I'll aim to fill those and hopefully have some leftover.

-Anthony

Re: INJECTOR UPDATE

Posted: Wed Aug 02, 2017 8:51 am
by LivingLegend
LivingLegend wrote:....I also shot the waxes and cores at Barry's for all of the Nathan's bodies....
I should clarify.... I shot all of the body waxes (and it's cores) only for the Nathan's initial production run, which was fifty. Barry shot the waxes for the rest of the injector's castings.

LL

Re: INJECTOR UPDATE

Posted: Wed Aug 02, 2017 7:57 pm
by bill4227
PM sent.

Bill D

Re: INJECTOR UPDATE

Posted: Thu Aug 03, 2017 10:40 pm
by Rich_Carlstedt
Anthony and Dave, its great to hear you both are keeping the candle lit !
The hobby certainly needs your support.
I helped Emery Ohlenkamp cast the last few hundred of his injectors and thought I should comment.
Em did not use wax , but did sand molding . The molds were made with permanent steel patterns and a thermo- set "fine" sand mix.
( the molds and cores were baked and then assembled individually - the alignment bosses were so accurate . the finished bodies look like they were wax cast )
Em used Manganese Bronze and it came in virgin ingots and yes, he was careful to use flux/degasser before we poured the melt. The metal was very pure , but you still pick up dirt/oils in handling, as well as oxygen and moisture
We did about 40 to 60 bodies at a time.
Not only were the bodies inspected, but Em assembled and checked every new injector with steam and water to ensure output requirements were met. Then they were cleaned and packed

Rich

Re: INJECTOR UPDATE

Posted: Fri Aug 04, 2017 8:07 am
by Fender
Rich,
Do you know why Emery chose manganese bronze? I know from experience that it is more difficult to machine than other bronze alloys.

Re: INJECTOR UPDATE

Posted: Fri Aug 04, 2017 2:07 pm
by BClemens
Fender wrote:Rich,
Do you know why Emery chose manganese bronze? I know from experience that it is more difficult to machine than other bronze alloys.
Yea, but I like the way is 'squalks' with a slightly dull cutter! Making noise is a pocket of busyness.

BClem