I mill it .015" with a rough profile. This pic does not do justice for the rough profile. But it makes for a great texture for spraying

 

cool. how thick is the factory chrome? gotta be way less than 15 thousandths...

pat

 

Then the sprayed coating needs to be about .030" and grind and finish polish to spec. That leaves a .015" coating.

 

It is a plating so it is only a couple mils at the most. But we have to fix wear which is in the thousanths

 

yeah, i know i just wondered. sounds like you got everything figured out just right. i'm counting on sending you my housings for my next rebuild... (hopefully 3 of em )

pat

 

Scalliwag,

I'd first like to say WOW, I'm impressed with what you have done. Although I have a Mechanical Engineering degree, I couldn't have designed 1/2 of what you have done so far. Almost makes me laugh when I see the other guys on the forum majoring in engineering saying once they finish school they'll be able to help. Truth be told, most engineering curricula won't teach them about anything you are working on/with.

Regarding all the testing youl plan to do to come up with the optimum settings for your custom equipment, I'd like to offer a thought that may speed up the process.

Although I'm not a statistician, I do know that what you are planning is referred to as a "Design of Experiments (DOE)" in the statistics world. DOE is used to determine how different variables affected one another, i.e. how many inputs affect one of more outputs, when a person wants to minimize the amount of testing they conduct. Researcher's use it in the chemical industry when developing products. For example, if a polymer is created using a reactor i.e. pressure vessel, researchers can control things like temperature, pressure, flow rates, raw materials characteristics, etc. --- many variables. To minimize the number of different tests they have to conduct to develop a polymer with specific properties, they run DOE's and use statistical software. The software I was trained to use during my Six Sigma days is called JMP (pronounced JUMP). It is by SAS Institute (http://www.jmp.com). An explanation of DOE can be found here:
- http://www.asq.org/links/design_experiments.html, or
- http://www.objectivedoe.com/whatisdoe.php

I'm not providing all of this expecting you to become a statistician, just wanted you to know so perhaps you could find someone familiar with DOE and save yourself a lot of time. Perhaps your contact selling you the wire and offering to do your end product testing has access to someone that could help you.

 

yeah, i know exactly what you mean, technomentor, I like the doing stuff side of engineering, and I came to school hoping to learn about that, which has been a disappointment. Not to say that there is anything wrong with desk engineering, obviously it works well, as most everything is designed that way nowadays; but that isnt my kind of thing. It almost seems like someone who goes to a community college and gets a 2 year mechanic's degree will know more about real-world things than most of the people i graduate with will.

I'm hoping that having some real skills to go with my engineering degree will be an asset, but im not counting on it, especially since i'll have to limit myself to jobs in which I get to actually DO something, and i dont know how many of those are available.

pat

 

Yeah Scalli's machine for milling, from what I remember, is pretty bad ***. I'm sure it took a lot of time and developement. And both of you are right, engineering courses don't let you do too much hands on stuff. Of course senior year you get to pick something and go into a little bit. But there are fun courses you can take at most universities, you just have to find them. I actually found a turbocharger lab last semester, we won't go into the details of how I found it, but I found that there are a couple classes where you actually get to use the lab constantly, and they work with a couple different companies on some R&D, obviously the lot of it happens within the companies own test facilities. I'll hopefully be taking some of those courses next year if I can alot time.

- Steiner

 

In defense of those that said they would like to come help me; they did indicate that they wanted to help in terms of giving a hand and learning some things from me. But I know that the skills they bring like AutoCAD would be very helpful to me.
I am not sure if it was in posts or PM's but both indicated they mean help in more of a "roll up their sleeves" and follow the lead.

There are also strengths in discipline that they almost have to be better than me at. I am like a bull in a china shop. For me to document and work out the finite details is incredibly painful for me. It is my nature to bounce all over the place. The best thing for me is to let something go at a certain point and let someone else polish the process.
I get by but it is against my nature and awkward for me.

I am often my worst enemy. You have never seen anyone that can lose **** as fast as I can. I spend more time looking for tools than working
Under these circumstances just to have someone disciplined that could cross T's and dot I's is very valuable. Of course I am afraid I might drive them crazy because that may be more work than they ever imagined.

I will read up on the DOE stuff. That sounds interesting. Thanks for the hookup.

 

yeah... i signed on for this stupid dual major program, so all my electives are picked for me, so i dont get to take fun courses like that. turbo lab sounds frikin sweet tho...I am on good terms with a couple of professors who are willing to answer my 'hands-on' questions, and i'm working on extracarriculars that will let me play with some of the equipment they have here... especially the dyno

its kinda sad that a full time engineering student can't even get his hands on a welder here. or even a jack to change my wheels when i got new ones..had to go buy one.

what year are you in, steiner?
second semester sophomore here.

pat

 

Yeah, I think Pat and I both had the same thing in mind, as far as work. I don't want to speak for him, but I know I am not at a point near where I would be able to be extremely beneficial to Scalli in the analytical process of designing a machine as a solution to a problem. I was pretty much thinking that I would be basically making runs on some of the items they sell, cleaning up shop, doing work with autocad etc. Pat I am first semester Jr year. I dicked around my first year and didn't get the courses done that I needed to. I did very well in the classes I took, I just wasn't taking the right classes. So I paid for it last year and this year in a scramble to get the courses I need in. The good thing is that I pretty much have all of my gen ed's completed aside from gym classes. So the rest of my schooling will be somewhat boring as far as diversity goes i.e. next semester I'm taking Physics 212, 213, Emch 12, 13, and Math 220, 230 that's it. My advisor asked me if I was taking on bets on when I'd commit suicide, it was pretty humorous. How about you Pat? You said you were Aerospace, but are double majoring? What is the other major then?

- Steiner

 

wvu has this cool program where you can get 2 seperate degrees, one in mechanical e, one in aerospace e, and they tout how you only have to go one extra semester. they dont yell so loud about the 18-20 hour credit load, but oh well. i dont even get to take gym class. lol.

my next semester will be calc 4, dynamics (dropped it this semester- middle eastern guy i couldnt understand), mechanics of materials, dynamics and strength lab, fluid mechanics, honors add on for physics 111 (couldnt schedule it last year), and microeconomics (see what i mean about the choice of electives they give us)

and yeah, you are right, i was thinking of basically being shop bitch too. its worth doing shitty jobs if you get to learn cool stuff. last summer i worked for a local mechanic, basically i was the only guy there and i worked on whatever POS he had for me that day...really crappy cars usually. but it was worth it for the times that he was around because i learned so many cool tricks. plus one time i got to work on a Peterbuilt, which was nifty.

emch is mechanical engineering, right?

pat

 

Damn that sucks really bad. It seems to me that the best thing you could ever do for an engineering student is to have their first year rolling up their sleeves and doing more hands on.
Things like "Junkyard Wars" or whatever version of that depending on the field seems like it would do wonders.
I was really fortunate to come from a family with some very resourceful people so I kind of grew up in a "Junkyard Wars" environment. :talking: With the custom car work my Dad did just about everything I saw was kind of engineered as it went in a lot of ways. But that is not to say it was not very well done also.

 

I agree with you 100%, I think it really helps engineers in problem developement, how to analyze, and how to solve a problem, if they are out in the field seeing the problems and using their heads to make a thought process to figure out what the problem is and how they could solve it and from there what the best solution would be. But I guess that is what internships, and the first four years of work is. Although from what I've heard, the general jobs you get before your PE are pretty crappy. But this is coming from engineers that started out 20 or so years ago so I don't know how much it has changed.

- Steiner

:edit I just read what the name of your picture is, and fell on the floor laughing.

 

yeah, me too. my family is really poor, so i always got to do stuff the hands on DIY way, which now im pretty glad about. nobody else in the family is into nice cars, but we always fixed our own, and being an adrenaline junkie, i kinda naturally just fell into the custom car thing.

i know exactly what you mean about the school thing.. i only know a few other people who know anything about real world application of what we learn here, and unfortunately, i find myself kind of despising the booksmart engineers that make up about 90% of my class. they get better grades than i do fairly often, but they cant even change a tire, and i dont see how someone like that can design a working machine.

then again...if you look at cars nowadays, you can see a lot of effects of it. like the fact that there are a few models where you have to pull the engine mounts and rock the engine on its side to change the plugs. that wasnt designed by someone who ever worked on a car.

pat

 

You guys have to check this out. BanzaiToyota gave me link a while back to www.shopfloortalk.com There is this guy over there named "Franz" that I can't help but think of my Dad (he died in '92 BTW) he says stuff the same way and all This guy has seen and done alot. People like him are priceless.
Now I am going to give you a link but you guys just kind of take my "pencil pusher" remark with a greain of salt when you see it.
What you have to read is how these guys built a shipyard back in 1942. They built these huge cranes and the way they made these huge gears is just amazing.

These are the guys that should be teaching some courses

http://www.shopfloortalk.com/forums/...read.php?t=964

 

Damn well I was trying to sleep. First I'm unfamiliar with the basic ceramic structure, but would it be possible to make an alloy persay, of a ceramic and a metal? Also how hot does the ceramic need to be to coat? I think you guys can figure out where I'm going with this. I'm not to confident on this because I believe this would have been developed long ago if it were capable of it, but none the less I am interested to see why it can't be applicable. Okay now back to sleep.

- Steiner

 

yes, it is possible to make an alloy of ceramic and metal. bikes and planes are made of it. i was under the impression that the wire scalli is using is made of some such. call me dumb, but i dont see where youre going with it, unless you mean to somehow plate it directly onto the housing?

pat

ps scalli that thread is hilarious, but damnit, now i have one more forum to spend 3 hours a day looking at. lol.

 

This link touches a little on what is referred to as "cermet".

https://www.rx7club.com/showpost.php...6&postcount=34

 

Pouring sand into the gears in sets to finish them is ingenius. Hell l would have dicked around for days trying to file, sand, etc. Stories like that you remember and some day you may find yourself in an odd situation and that idea or something you derive from it saves the day for you

 

hey franz is on a couple of welding forums I am on, hes great isnt he.

BTW a little late but here is some design I cam up with a week ago, been busy helping the in-laws with a house.

this is plasma flame single wire feed... I think will work...drk blue is water for cooling.

www.crappie-performance.com/plasmamig.jpg
ps mspaint sucks

 

Cool design Hans. It would be trickier to make than what I built though. I am also concerned about having the wire come in from the back. Since I can't make a tight radius without binding the wire it may increase the length of the gun.
Granted that it would be optimal to have the wire traveling in the direction it is being sprayed. But I am hoping that I can strike a balance between the air pressure, amperage and wire speed to redirect a spray pattern.

If this does show signs of promise I have an idea for water cooling the gun. But for now I am going to sit tight and see how the gun responds with the right wire.

 

Scalli Considering the size of the head that you made, it looks like you could get away with a 30 degree or so angle. That limits you to only being able to work on the housing from one side, but would let you move the head further back.

- Steiner

 

only thing im worried about is with too much angle on the spray, is there gonna be poor adhesion in the middle of the housing?

 

There is something I had read about how many degrees you can get away with but I cannot remember where I read it. The housings are going to be on a rotating fixture and the gun will be on a post coming up from the bottom. The table will be cammed so that the gun will always be the same distance from the wall.
The post that the gun is on will only travel up and down. I will run it a full turn then raise the gun and run it another turn and repeat until finished.
But before any of that I will make sure it works on side housings. I will use an old rotor housing bolted to a side plate and blast the hell out of the side plate. I was going to mill the area just inside the o-ring grooves until I got the big compressor. With the right grit and air pressure I can get that dow to an art real quick
But side plates are still first on the agenda since I talked about that somewhere buried in the 38 pages