Can you spot the powder coating flaws on these M62 parts?

[Concrete Donkey]

I decided to have the timing & valve covers done this past week. The timing covers were done in a wet silver, while the valve covers got coated in a wrinkle black. Can anyone spot the problem?


http://i277.photobucket.com/albums/kk77/Firezomby/df70db4d-dacf-430a-9343-ba02e7286479_zpsbe2777d9.jpg (http://s277.photobucket.com/user/Firezomby/media/df70db4d-dacf-430a-9343-ba02e7286479_zpsbe2777d9.jpg.html)

http://i277.photobucket.com/albums/kk77/Firezomby/2013-12-04234030_zps968ed703.jpg

(http://s277.photobucket.com/user/Firezomby/media/2013-12-04234030_zps968ed703.jpg.html)http://i277.photobucket.com/albums/kk77/Firezomby/2013-12-04233933_zps3aed9058.jpg (http://s277.photobucket.com/user/Firezomby/media/2013-12-04233933_zps3aed9058.jpg.html)

http://i277.photobucket.com/albums/kk77/Firezomby/2013-12-04233915_zps5f76d373.jpg (http://s277.photobucket.com/user/Firezomby/media/2013-12-04233915_zps5f76d373.jpg.html)

http://i277.photobucket.com/albums/kk77/Firezomby/2013-12-04233902_zpsf5534463.jpg (http://s277.photobucket.com/user/Firezomby/media/2013-12-04233902_zpsf5534463.jpg.html)

http://i277.photobucket.com/albums/kk77/Firezomby/2013-12-04233852_zpsba8b9051.jpg (http://s277.photobucket.com/user/Firezomby/media/2013-12-04233852_zpsba8b9051.jpg.html)

http://i277.photobucket.com/albums/kk77/Firezomby/2013-12-07041631_zpsab1294c9.jpg (http://s277.photobucket.com/user/Firezomby/media/2013-12-07041631_zpsab1294c9.jpg.html)

http://i277.photobucket.com/albums/kk77/Firezomby/2013-12-07041755_zps29194f81.jpg (http://s277.photobucket.com/user/Firezomby/media/2013-12-07041755_zps29194f81.jpg.html)

http://i277.photobucket.com/albums/kk77/Firezomby/2013-12-07041747_zps02e00110.jpg (http://s277.photobucket.com/user/Firezomby/media/2013-12-07041747_zps02e00110.jpg.html)

http://i277.photobucket.com/albums/kk77/Firezomby/2013-12-07041722_zps0d241dd9.jpg (http://s277.photobucket.com/user/Firezomby/media/2013-12-07041722_zps0d241dd9.jpg.html)

http://i277.photobucket.com/albums/kk77/Firezomby/2013-12-07041707_zps96c2674f.jpg (http://s277.photobucket.com/user/Firezomby/media/2013-12-07041707_zps96c2674f.jpg.html)

http://i277.photobucket.com/albums/kk77/Firezomby/2013-12-07041638_zps7d5a7f70.jpg

(http://s277.photobucket.com/user/Firezomby/media/2013-12-07041638_zps7d5a7f70.jpg.html)

[JimLev]

Some are pretty obvious. I've said more than once that the flaws in the castings need to be filled with Marine JB Weld before the powder is applied.
Some of them are highlighted by the light and angle when you took the pics.
The wrinkle black does a pretty good job of hiding a lot of casting flaws.
I'll be doing my front covers when when the time comes to replace the gaskets.
Overall they came out OK, when you get them back on and the other parts installed you won't notice most of them.

[Concrete Donkey]

Some are pretty obvious. I've said more than once that the flaws in the castings need to be filled with Marine JB Weld before the powder is applied. Some of them are highlighted by the light and angle when you took the pics. The wrinkle black does a pretty good job of hiding a lot of casting flaws. I'll be doing my front covers when when the time comes to replace the gaskets. Overall they came out OK, when you get them back on and the other parts installed you won't notice most of them.

There were no flaws in the valve cover, but out gassing occurred through the coating. Correct me if I am wrong, but would this be considered an error on their behalf? It seems to have fish-eyed on the front portion near the oil fill.

I didn't make too much of a fuss over the silver, being that it's only visible via certain angles. I asked prior to having them done, and the owner insisted that they were ready to coat. He stated that the silver run was due to the metal, and that the magnesium covers will always outgas some remnants. I'm not too sure that I buy it, but I don't have the knowledge to back anything up.

[JimLev]

The first pic looked like an indent in the casting, hard to tell from the pic. So it was an outgas bubble, bummer.
Yes, error on their part. After cleaning the covers and before the powder is sprayed on they need to be heated to 50 deg above the powder cure temp, usually 450F. Higher would be better, however these are magnesium so you can't go too much higher. This drives the oil out. They then need to be wiped down again, I usually heat them up again to drive off any remaining cleaning solvent. Then I apply the powder and do the cure at 400F.
Runs are from applying too much powder.

[edjack]

Best to find a shop that specializes in motorcycle parts. Bike owners are VERY particular.

[mxchris727]

Where did you get the work done? I've been thinking of doing the same to my 540

[Concrete Donkey]

The first pic looked like an indent in the casting, hard to tell from the pic. So it was an outgas bubble, bummer. Yes, error on their part. After cleaning the covers and before the powder is sprayed on they need to be heated to 50 deg above the powder cure temp, usually 450F. Higher would be better, however these are magnesium so you can't go too much higher. This drives the oil out. They then need to be wiped down again, I usually heat them up again to drive off any remaining cleaning solvent. Then I apply the powder and do the cure at 400F. Runs are from applying too much powder.

The owner claims that the valve cover was only heated up once at 450F for 30 minutes. I read on a few other sites that magnesium typically requires a longer cleaning regiment, along with 2-3 bake sessions to clear out the oil/solvents. It's beginning to sound like this shop lacks experience.

[cwise12]

At least they got the color right. The shop that did mine somehow didn't use the color I requested, and the covers turned out much bluer than the color chip that we matched just about perfectly to Titanium silver.


George, they'll look awesome installed on your car. Nobody will notice!

[Concrete Donkey]

At least they got the color right. The shop that did mine somehow didn't use the color I requested, and the covers turned out much bluer than the color chip that we matched just about perfectly to Titanium silver. George, they'll look awesome installed on your car. Nobody will notice!

It must be tough to find a legitimate powder coating shop. Did you ever mention it to them?

I agree, but I just couldn't live with all those marks on the front of the one valve cover. I got the specials treatment after walking back in with said parts. He says that he will do it again, but it might come out worse than before. I wish they would have mentioned this during the quote process.

[cwise12]

It must be tough to find a legitimate powder coating shop. Did you ever mention it to them?

Nope, I didn't have time to have them do it again. Close enough....

[DatTugrut]

I think they look pretty good.

[Concrete Donkey]

I think they look pretty good.

One valve cover was extremely noticeable in person, but the rest came out great. I was planning on soda blasting the motor and thought that these imperfections would stick out pretty badly.

[pizzaman09]

Might I ask how much all of the powder coating cost?

[Concrete Donkey]

Might I ask how much all of the powder coating cost?

Not a problem. The entire job ran $200, but we glass beaded everything prior to bringing them in.

[240sxguy]

Glass bead really isn't the right media to prep with anyway, not a knock on you at all but the coating shop should have identified that. It doesn't leave much tooth and tends to peen the pores in the metal shut. I hear that the valve covers are difficult to get coated well, and to be honest I am not looking forward to doing mine. I have outgassed some parts for a long time and still had them outgas in the coating process. Hopefully they get it done better on the second go-round.

Otherwise, I really like your color choices.

[Concrete Donkey]

Glass bead really isn't the right media to prep with anyway, not a knock on you at all but the coating shop should have identified that. It doesn't leave much tooth and tends to peen the pores in the metal shut. I hear that the valve covers are difficult to get coated well, and to be honest I am not looking forward to doing mine. I have outgassed some parts for a long time and still had them outgas in the coating process. Hopefully they get it done better on the second go-round. Otherwise, I really like your color choices.

Does that apply to aluminum? I figured that sand/aluminum oxide would leave pitting in the timing covers, so I went with the glass beading. I spoke with the owner about the beading, but he never mentioned an issue.

I was reading that the prep process may also involve some sort of chemical cleaning tank to ensure that all of the contaminants are removed. I mentioned a few of the articles, but he quickly dismissed them by stating that every shop has their own method.

[Concrete Donkey]

Some are pretty obvious. I've said more than once that the flaws in the castings need to be filled with Marine JB Weld before the powder is applied. Some of them are highlighted by the light and angle when you took the pics. The wrinkle black does a pretty good job of hiding a lot of casting flaws. I'll be doing my front covers when when the time comes to replace the gaskets. Overall they came out OK, when you get them back on and the other parts installed you won't notice most of them.

I just wanted to note that these pictures are not all of the same flawed pieces. Sorry about that.

[geargrinder]

I just had a set of VC's done by a guy in wrinkle. He confirmed the mag is a beyotch, but he'd done lots of BMW mag covers before including the V8 ones which he immediately said "oh yeah so another set of those" so he'd sorted out the tricks I guess. I've been using him for years so I trust his quality and job, they look great as-is but of course time will tell.

One major thing to watch for is residual media though - a machinist I use told horror stories and convinced me to at least super pressure wash everything I have PC'd, if not more, and some parts he's hot-tanked for me to be sure all the grit is out. The M62 covers don't have too many cranny's for stuff to hide in but nonetheless be sure you go overboard on the washdown after they've been done.

[240sxguy]

Does that apply to aluminum? I figured that sand/aluminum oxide would leave pitting in the timing covers, so I went with the glass beading. I spoke with the owner about the beading, but he never mentioned an issue.

I was reading that the prep process may also involve some sort of chemical cleaning tank to ensure that all of the contaminants are removed. I mentioned a few of the articles, but he quickly dismissed them by stating that every shop has their own method.

I was mainly just thinking outloud here. Most coaters I have read about online use a more coarse grit before coating to improve adhesion. I think it's also intended to break some of the outgassing passages open but don't quote me there. They're right, everyone has their own methods. Unfortunately, the end results aren't always the same :)

[Concrete Donkey]

I was mainly just thinking outloud here. Most coaters I have read about online use a more coarse grit before coating to improve adhesion. I think it's also intended to break some of the outgassing passages open but don't quote me there. They're right, everyone has their own methods. Unfortunately, the end results aren't always the same :)

Lmao

[JimLev]

I've blasted with course media and stripped with paint remover. Haven't had a problem with either method having the powder sticking to the VC.
I prefer to use stripped which leaves the surface nice and smooth and provides a nice smooth finished product.
The down side is using stripper takes 3 forevers to get the covers ready, 3 hrs/cover.
Getting all the oil to outgas and cleaned off is the key to a lasting finish as you probably know.
I can't see any powder coating business spending all this time for $200.
Hope they do a good job when they redo it.

[Concrete Donkey]

I've blasted with course media and stripped with paint remover. Haven't had a problem with either method having the powder sticking to the VC. I prefer to use stripped which leaves the surface nice and smooth and provides a nice smooth finished product. The down side is using stripper takes 3 forevers to get the covers ready, 3 hrs/cover. Getting all the oil to outgas and cleaned off is the key to a lasting finish as you probably know. I can't see any powder coating business spending all this time for $200. Hope they do a good job when they redo it.

I hope so, too. The owner seems like a good guy, and since they were already stripped, I figured his pricing was spot on:

- $40 per valve cover
- $30 per upper timing cover
- $50 for the lower timing cover

I'm fortunate that he accepted the return, even though he said it may come out worse. I would have gladly paid more for the proper prep work to be done. I'm still a bit bummed out about the one upper timing cover smudge, though.

[Rallim]

Those prices are cheap. I paid $150 I think for both of my valve covers alone, I wouldn't be complaining. They told me straight up due to the pitting in the paint/powdercoat/*)$* BMW used on the valve covers there'd be some pitting after they were done, which made perfect sense to me. A couple spots, but they still turned out great.

[Concrete Donkey]

Those prices are cheap. I paid $150 I think for both of my valve covers alone, I wouldn't be complaining. They told me straight up due to the pitting in the paint/powdercoat/*)$* BMW used on the valve covers there'd be some pitting after they were done, which made perfect sense to me. A couple spots, but they still turned out great.

I would have gladly paid the additional cost to have it done right the first time, but it is what it is at this point. I can understand the pitting, because that is a metal defect, but improper powder coating prep is something beyond my control.

[Only1Balto]

They look amazing man, flaws or not when I compare them to mine.

[Concrete Donkey]

They look amazing man, flaws or not when I compare them to mine.

Thanks, and the flaws stick out more to me because I put a buttload of sanding into each piece prior to powder coating. Below are a few before pictures of when I first purchased the 540.