GUITARJUNKIE28

i don't think that has anything to do with the size of the corner piece. apex seals tend to break at that sharp tip (unless you grenade the thing), so it's logical you'd have the damage in that area.

btw, RA is out of the super seals for 6 weeks..

BoostedRex

I know that there is one shop in the Sacramento area that has been testing out these new RA seals for a little while now. The owner of that shop says he's had some really good experiences with them.

Zach

t-von

iTrader: (8)

I'm not talking about the breakage damage, i'm talking about the groove the side piece causes from normal useage around the housing on the edge. My pic shows that groove on the bottom part of the housing.

mono4lamar

iTrader: (32)

would like to get a pair of the new seals for my new motor! hopefully they can reappear this week cause thats when both my blocks are goin out

GUITARJUNKIE28

oh my bad.
but that happens on both edges of the rotor housings.

i remember reading somewhere about that being the reason the renesis has 2 oil injectors angled right at the corners--to put more oil there and prevent the flaking.

unfortunately, i've seen some very minor flaking in one renesis motor already (~30-40k miles). however, that was a turbo motor, and i don't think he was pre-mixing anything extra over the stock omp. i recommended to that guy that he either added a bit of pre-mix 2-3 oz per tank, or have racing beat do thier thing on the omp. the rotors were way cleaner than any other renesis i've taken apart so far.

TonyD89

iTrader: (10)

I'm sorry, but I just have to chime in here. Nitriding is not a universally applied description of the process. It can be done to various depthes on the same matterial and the type of matterial may effect its abillity to accept the process.


I'm very curious as to what process. they are using. It can vary from .0005" to .030" penetration, depending on what they use. The deeper the penetration the longer the matterial is subject to high heat and subject to distortion.

If they are nitriding oversized seals deep and then re-machining to the proper thickness, then that would be the way to go (other maching could also be needed to bring it into spec).

If they just do a short layer (.0005), then it will be short lived.

Any heat treating done to the seals will be subject to heat as "draw temp" durring the nitriding. This could effect the underlying hardness of the seals.

RETed

That sounds expensive...


-Ted

TonyD89

iTrader: (10)

I was at work today and realized I forgot about another commonly available method they could be using.We coat a lot of cutting tools with TiAlN (titanium-aluminium-nitride). It is a coating. It doesn't soak in to the material like gas-nitriding. It is considered a "ceramic" coating. Very slick and hard. Also purplish in color.

Once again, typical thickness is .0005". What happens when it wears away? I would really like to find out what they are using.

I dont know if I would recomend taking a file to my seals but nitriding is file hard(the file slides without cutting and with pressure, the file is dulled). If it is a thin coating the corner af the file will dig-in under pressure. Maybe using a very small jewelers file on the bottom side? I dunno.

TonyD89

iTrader: (10)

As far as expensive to do, nitrided steel can be ground on a wet surface grinder. I've done it many times, A lot of heat so light cuts with a coarse, soft wheel.

Here is something to chew on. Make seals .002"-.005' thicker than needed, 24 hr gas nitride(~.010"), regrind to what you need. I'm sure Mazda or a racer has tried this.

t-von

iTrader: (8)

I'm always down to experiment. Could you coat some apex seals if I send them to you?

GUITARJUNKIE28

i've always wondered why they haven't ceramic coated apex seals.

diabolical1

iTrader: (3)

^ interesting thought ...

RETed

Cost too much?
People are already bitching about $60 / seal.
Look at all the people going non-Mazda...
Would you be willing to pay $100 / seal if they were ceramic coated?
Most people would not.


-Ted

TonyD89

iTrader: (10)

If little ole St Lou has a coater, shouldn't be to hard to locate in your area. Look under industrial coatings, cutting tools, tool supply houses, and heat treaters.

Yes, I will have to verify( because it would go through work), but I could probably get it done. Full disclaimers attached.

If anyone can get more info about what RA is doing, let me know.

GUITARJUNKIE28

you wouldn't have to start off with a $60 mazda seal that has undergone a bunch of processes..

start off with a $200 set and go from there. even if the cost got upwards of $3-400 a set, i bet loads of people would buy them. i'd givaniggachance

RXBeetle

Ion nitriding doesn't subject the material to as high a temp as gas. I will be taking some side housings for nitriding soon, hmm maybe I should take my apex seals with me. I have a brand new set or RA seals sitting on my desk here. My only problem with nitriding is that the harder the seal is the more wear you subject the housing too. Surface hardness is typicaly 65 RC after nitriding.

diabolical1

iTrader: (3)

what's RC stand for?

Speedworks

Just sharing a few pics of my 13B-REw rear hosuign I took apart recently. Engien should have about 60.000km accoriding the previous owner but I think it's a bit over that.

front housing did not have any sign of corner seal marking, not even on the combustion piece of the housing. Just a moderated difference in chromium glaze where it was.

Rear housing was fine as well. Only on the combustion piece (from exhaust port and downwards) one side had signs of flaked away chromium (see pistures).

I estimate the widest flake to be 1.5mm to max 2mm.
Housings are free from other marks or scratches. I have been in cotact with RA as well about their rebuild kit which I will most likely buy.

Just deciding what seals to go with and wether I put them back in as they were or to now but the large apex seal piece in the other direction (where the corner seal used to be) to make up for the marks.

Just metnionning... the engine was using the 3-piece Mazda seals from factory.

Sorry for the fuzzy pics. My Digi is plain useless

TonyD89

iTrader: (10)

I'm pretty sure that true nitriding is harder than glass,above 82 RC. RC stands for Rockwell "C" scale. A way of measuring hardness.

I seriously don't believe that a .0005" coating will offer up that much more life. The reason the TiAlN coating lasts so long on cutting tools is because the underlying material is super hard (either carbide or HSS).

The soft underlayer of a thinly nitrided or TiAl (there is also AlTiN coating that is different, believe it or not, and using the same elements that is more heat resistant) WILL NOT give you the same resulting wear as a hard underlying material.

The problem I see with traditional nitriding of significant depth is the embrittlement of the sharp edge of the long steel seal (where it meets the little triangular side piece). This area ia already a problem. We have problems with chipping on thin and feather edges in our die parts using this process. And the heat associated is around 900 degrees. The heat might distort the seal.

Something else to chew on! You can mask a piece to prevent the nitriding from taking in certain areas. And remember, with traditional, you can pick your depth of penetration.

RXBeetle

The highest RC I've seen for nitrided steel is low 70s, even at that the hardness usually drops off very fast. I didn't even need to use coolant on my side housings when I ground them.

I've been thinking about seals all day after reading this and here are a few thoughts I had.
There are two ends of the spectrum
1: Let a softer seal wear and the subject the housing to less scoring and abrasion for long term reliability.
2. For all out preformance screw longevity use whatever will take the abuse for the necessary durration to win.

Most of us fall somewhere inbetween, we will sacrafice some engine life for a more durable seal that will take more abuse than a stock seal. If the new RA apex seals do what they say they seem to fall right into that category. A little less forgiving on the housings but less risk in the short term.
I think the big risk with a harder seal is when using an already chipped housing. A softer seal will wear faster as it leaves a little of itself behind on jagged edges. A hard seal may just plow right through instead of wearing. This is just a educated guess, maybe were lucky and a harder seal will be more inclinded to skim right over chipped chrome without catching it.

GUITARJUNKIE28

just use tool steel for that.

i'd like to find a way to make that sharp corner stronger. less angle would be good, but bad for sealing. if your seals split down the middle, you were flat out raping on it too hard. if they chip at the corner, you just went a liiiiiiittle bit farther than you should have.

Glassman

iTrader: (1)

"2. For all out preformance screw longevity use whatever will take the abuse for the necessary durration to win."

You do know that you can have both?

"i've always wondered why they haven't ceramic coated apex seals."

Because it would probably come off.

If you want to learn more about liquid nitriding on apex seals you can contact Hayes. I made a set of liquid nitrided 2 pc 3mm 13B apex seals for testing over 7 years ago. Problem was I could never get any real data back and could not get the seals back for evaluation either. They installed them in their N/A rotary parts truck and used it for making their deliveries. From what I could get, they claimed they worked well but chrome wear was somewhat concerning (always comes down to compatable materials). The base material was fairly soft and through hardened to about 30 - 35 RC. The parts then were liquid nitrided using sulphur in the process for self lubrication and corrosive resistance. This turns the parts black and gives an approx 0.004" case hardness.

These were eventually abandoned in favor of ceramics and i've never looked back since.
Happy Trails

GUITARJUNKIE28

i like my depleted uranium idea

banzaitoyota

Sorry, I pretty much used up the in-stock supply when I designed the Glovebox ventillation recirc diffusers

GUITARJUNKIE28

damn! let's go jack some from a tank