OhBeanie

Hey guys, I've done research on the topic and I've found Lynn Hangover's method of prepping the irons. If you're familiar with his method, do you recommend it? I've been testing it on a dead iron and from what I can tell it's been working but I just wanna see what you guys recommend before I do it to my rebuild irons. Also what should I do with rotor housings? Do I just clean the outsides and leave inside face alone or is there a way to sand the inside of rotor housing?

zli944

Curious, what's Lynn Hangover's iron prepping method?

As far as DIY resurfacing, I wasn't aware you had options for either. My experience is with a 13B-REW, not a renesis, but I think the principles are the same. The iron surfaces need to be ground down and renitrided and the rotor housings CAN be ground down so it's even, but now the interior dimensions of the housing would not be the same, and depending on how much you grind, I suppose you could wear through the chrome finish layer.
On my FDs rebuild, I didn't know better and went with a used rotor housing from a forum member. I got extremely lucky because it was in great shape but imo, it's better to bite the bullet and spend the cash on new rotor housings.

OhBeanie

This is what RX7 Club recommends to prepare the iron surfaces for rebuild. My iron faces and rotor housing are perfect and don't have any scratches, the faces are just shiny. I'm just re using the irons from my original build, do I have to get new iron's if they're still in good condition? I'm just asking the best way to prepare them for a rebuild! Do I want the iron surfaces to be shiny or a matte grey? ​​​​

Loki

iTrader: (1)

What generation of rotary are those instructions for? I dunno how applicable they are to the renny. If you don't have chatter marks or peeling and everything is square, flat and in spec, I wouldn't touch it. And it it's not flat or flaking or chattered, then sanding isn't a solution?

But I'm also not a rebuilder.

OhBeanie

Those are for an RX7 because I couldn't find any info about preparing RX8 iron's! But yeah my iron faces and rotors are completely solid, no chatter marks or anything! If that's the case, and I don't get any other information on it, I think I'm just gonna clean the outsides of the irons and rotor housings then just put it together!

kevink0000

Lynn's method is way too aggressive for the Renesis in my opinion. You will quickly blow through the nitriding and end up with very soft surfaces which will quickly wear.

Also, if you are searching, the last name is Hanover, not Hangover.

Many builders leave good irons alone and get good results. I personally did not do this, I wanted a better surface for break in than a glazed piece of cast iron. I could be wrong or right, but I used lapping compound between two housings placed on top of one another. I moved the top housing in a random pattern until I had a uniform finish on both sides. It took a long time. Plus I was able to better see any wear present much clearer. I did not get anywhere removing enough material to affect the surface hardening. I used Permatex water based compound since I had used it before on piston engine's valves. I like the way the grit breaks down to fine as you are lapping. I just couldn't, based on piston engine rebuild experience, leave a glazed surface for new seals to break in on, even though it is done all the time by rotary builders. My $.02, FWIW.

OhBeanie

Thank you so much, I'm gonna try this on a couple dead iron's and see how they turn out before I do it to my rebuild irons! This is the exact response I wanted, I couldn't find any information on if you can put it together with shiny iron faces, I kinda figured you could but I just didn't have any solid information! You answered both my questions and I really really appreciate the input!

kevink0000

I used the water based Permatex lapping compound. I have always liked it better than the oil based stuff I have tried.
You can tell when the grit breaks down completely, and at that point I would clean it and start over. Lots of time. Nice finish though. Was it worth it? Don't know. Still sitting in pieces on the bench. Hope to have it running next month.