Your idea does sound good and reasonable (repairing housings). Mazda is not going to make the best housing just the most cost effective one, but anyway I'm not sure if someone else suggested this but I think to help you understand the repairing process you should research as much possible about the original manufacturing process

 

That's been covered fairly well. They use a SIP (sheet metal insert) with a hard chrome plating. The aluminum is cast around it. These two pages cover some of the details of the process.
http://members.rogers.com/sofronov/C...otary/12A.html
http://members.rogers.com/sofronov/C...otary/13B.html

 

I took the housings back to the spray shop so they could see just how badly they oversprayed them. The first housing was ground down a lot. The other housing was an 1/8" thick in some places. They are going to try to either EDM or use something they called a hydrotail which I guess is a water jet cutting system to try to get the housings back to where they need to be.
My bet is that it will not work so I am getting another set ready.

 

No posts in awhile.

Anything going on?

 

The spray shop and I are having a mexican standoff. For the timebeing I am concentrating on side housings since they are a simple spray procedure since they are flat.

 

Mexican standoff? As in communicating as seldom as possible so as to not inflame the soreness already present in the relationship?

Keep up your progress Scalliwag. In every forum there are members who are at the top of the food chain and I consider you one of them. You are doing something which no one else would even try, and producing convincing results. From one DIY'er to another, great work.

 

you have to finish it i just spent 3 hours at work going through 17 pages of posts.

Vic

 

It is still going to be finished. But if I am paying $250 per housing to get them sprayed and I have to go through this each time to try to complete one it is counterproductive and I would have to charge about $800 per housing because of the amount of time it takes.
One housing make take 2 hours when I get it back and another may take 12 hours and two trips to the spray shop.
Since I cannot control the spray process at this point and evidently they cannot either I am having to change the game plan to suit the situation.
I ran into a couple of minor situations with the machine for finishing the side housings. But they are not too big.
Since then I have spent most of my time working on a modular pport component system of tubes with aluminum connectors instead of the rubber sleeves seen on most applications now.
By far the biggest project is a slide throttle body setup that looks badass.
I don't want the spray shop to think I am in any big hurry to send them anything else until I have their best offer for making this right.
Since they have yet to be able to fix the housings they fugged up we have $500 plus the value of the housings that are the credit due to me.
They have not given me a price on spraying the sideplates at this point and I am afraid that right now they would try to overprice that so they would not have to do as many to cover their fuggup. But I would have to live with that price from now on.
So that is a dilemna.
Right now I can go in there and tell them that okay it's been 2 months since you jacked the housings and obviously we are not getting anywhere with them. Make me a real good deal on spraying sides and we will just worry about them for now and just give me and extra $200 credit for the ruined housings and the $500 of botched spraying.
I could do the side housings and if I make enough extra money to justify buying a used spray rig then I could set it up specifically for spraying rotor housings.
So that is the game plan. Keep an eye for the side throttle plates. Ken Scheepers got the motor running with the pport housings I built and it is running great.
He will be running the throttle body system and once we get a feel for what the final part should be I have to apply for a patent. Once it's in "patent pending" status I will post pics. They are 52mm each but since there is no throttle plate shaft in effect it is a little larger than that.

 

There is nothing that interests me more on this forum than this thread!
I am always looking for a new post.

Please finish the test product for all us people that don’t have the means capability or talent to pull something like this off.

Honestly if you think about it, it is truly amazing that you have made it this far, it is so close to becoming a reality. I only hope it does work out as you have theorized about simply respraying damaged parts and doing minimal work to repair bad scratches and damage.

And not to make you think people want to pay a thousand bucks for them but it sounds like you are trying to get the process down to a very economical level on par with a new set, but I think people would pay extra if the option to inexpensively reapply material over damaged parts and make them good as new where available.

And thank you for not only trying to develop new better parts for us but for the interesting read.

Take it easy man and good luck!

 

Scalliwag,
I got some scard 13BRE housings and sides, if you can perfect your process for a resonable price, I'll buy some!

 

why do you need to spray the side housings? i just got mine ground about .004 on a surface grinder and then lapped out the machining marks by hand..im sure you could perfect and mechanize that process, but it only cost me $120 and i have a very nice running rebuild now. as for the rotor housings, go for it man!

just my .02

-Pat

 

In order to get most side housing from high mileage motors flat you have to grind below the nitrided surface as you did. The plating maybe .002 at best. Since you went .004 this is a problem in the long run.
So what happens now is you have an untreated surface that will wear very rapidly.
I am sure some of the guys on the forum will confirm this because their have been many discussions about it.
Definately use Amsoil or a teflon additive and change your oil often.
If you let that motor sit for a long period without starting it the side plates are now succeptible to rusting more rapidly which would cause pitting. Not much pittting but it does not take much to affect sealing.

 

I was under the impression that there was no nitrided surface on the side housings, but only the rotor housings. mazdatrix does a lapping process similar to what i did for $50 a surface. according to them the only limit to how much can be taken off is the lenght of the e-shaft. they have no mention of a nitide surface on the rside housings. anyway i really hope you are not right bc i put a lot of time and effort into that rebuild..lol..

-Pat

 

Scally, I've got 6 housings and a 4 front/rear/side of each housings ready to send to you when YOUR ready.. I hope that this addition to your volume brings the price downand the leverage over the spray shop up.. If you need more volume then I know I can have @ 8 more housing ready to go.. I've been saving my housing just waiting for the time when you say go. I'm sick and tired of having beat up , scored, fragged.. and generally ratty housings as the only reasonable replacement for a truly poched housing

 

ok..well..****. i guess when you are ready youve got a set of my spare side housings to do, too.

-Pat

 

I guess you found the documentation on rotor housings being hard chromed and side housings being nitrided? Sorry to be the bearer of that news.

 

Hey, have you made any progress on your project scalliwag? Do you have a date set on when you're going to start this work or is it just it happens when it happens? I'm really looking forward to this so when I get my 3rd gen this december I can get you do to the housings right off the bat.

Keep us posted!

 

I am going to only do side plates to start off with. If they work out I will get a thermal spray rig and set up an ID spray head and build a rotating table with a rheostat to adjust the rotation and a cam mechanism to control the distance between the spray tip and the wall.
I cannot see these guys being able to control this spraying by hand. The **** is so hard to grind and finish that it does not take a lot to make my life miserable.
Spraying and finishing the flat surface of a side plate is easy by comparison.
I am still working on my slide throttle project and believe or not I am finishing a restore on an AE I picked up. It goes in for paint tomorrow so finally therest of the work does not involve me
I will be back onto this soon but just side plates for now.

 

whats a rotor housing.

 

it houses the rotor

 

I run a Makino a 77e high speed milling center with a 18k rpm spindel and two other cnc mills in a aircraft shops tool room I make dies that look like crome
but for this you would want to use a wire edm then plate it tain maybe ?
I don't know how well milling would work thats a deep side mill but you could use a large diam endmill to keep tool deflection down I gess you better have feeds and speeds right before starting
it just would be to easy to wire it on our fanuc I gess
I would like to see a G code program of the conture I any one has one?
I may need it someday!
can anyone tell me where to find the dementions of the housing a autocad drawing would be great
so I know what size I need to get back to after plating

 

Scallawag, I finally got that damned seires 4 13B apart. I compared its good housing to my good 12A housing... and wouldn't you know it, there is not any single place anywhere around the inside of the housing where they are not flush.

In other words, they are *not* different, 2mm seal to 3mm seal. The inner surface has the same dimensions.

 

PEEJAY,

are you saying what i think your are saying ?
can I put my spare 12a housings on my 13b and get it running ?
how about the rotors are they the same?

oh ya "will port for beer"
how much beer how much port

 

He was talking about whether or not the shape of the rotor surface of the housing. There was discussion earlier in the thread about the shape between some housings being slightly different.
The width of the rotors are different between a 12a and 13b.
To answer the question about using 12a housings with 13b sideplates. That would work with 1985 or older 13b sideplates. The newer sideplates have the water jacket o-ring grooves in the sideplate. 12a rotor housings have the grooves in them.

 

You can't use 12A rotor housings in a 13B.

However, there does not appear to be any geometry change between 3mm seal and 2mm seal engines - in other words, you can go right ahead and put 3mm seal rotors in a "2mm seal" engine, o 2mm seal rotors in a "3mm seal" engine.

Also, it means that when Scalliwag goes to machine the resurfaced housings, he doesn't need to have two different templates (or whatever is being used to decribe the machining process), since the trochoid dimensions are the same.