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Sun Jan 20, 2008 9:36 am

Here pics of my 25 hp case (April 1951) after chromate coating in Finland. Cases were originally coated like this by casting shop. This coating is made only for magnesium treatment.

Sun Jan 20, 2008 11:05 am

Vertanen=I like it! I like it AlOT! I am currently restoring a 1951 25hp Longblock for sale when finished and will intail the exact same Die Chromate Process as you have pictured. Like it or not It came from the Factory that Way "Originally!!!" And all future (VMR) Restoration will have the Die Chromate Protective Magnesium Coating as supplied by the Factory back in the day. Eric (VMR) Nice Pic's 8)

Sun Jan 20, 2008 10:52 pm

If you like to get this coating, at the first is good to remove all steel parts and also aluminum oil channel plugs. Removing steel parts because they corrode in strong acids and oil plugs because to get oil channels clean.

Stud screws are easy to remove without damages using 2-nut-system and local heating by torch. Then is left positioning pins, oil dipstick tube and oil pump suction pipe. They can remove without damage also by local heating and suitable tools.

Sun Jan 20, 2008 11:03 pm

virtanen wrote: Here pics of my 25 hp case (April 1951) after chromate coating in Finland. Cases were originally coated like this by casting shop. This coating is made only for magnesium treatment.

Question... how come the process did not give complete coverage to the case? (for example Joe Ruiz's cases which are uniformly covered)

Although I like the very inconsistent "used" vintage look it has.

Mon Jan 21, 2008 12:28 am

52HoffmanSplit wrote: virtanen wrote: Here pics of my 25 hp case (April 1951) after chromate coating in Finland. Cases were originally coated like this by casting shop. This coating is made only for magnesium treatment.

Question... how come the process did not give complete coverage to the case? (for example Joe Ruiz's cases which are uniformly covered)

Although I like the very inconsistent "used" vintage look it has.

Yes, the coating covers whole the case. Those areas which are originally machined or ground looks different than cast surface. And the tone is also different on different watching angles.

This is only for serious restorers who like to have fresh factory look and good treatment on mag case.

Mon Jan 21, 2008 6:37 pm

52HoffmanSplit wrote: virtanen wrote: Here pics of my 25 hp case (April 1951) after chromate coating in Finland. Cases were originally coated like this by casting shop. This coating is made only for magnesium treatment.

Question... how come the process did not give complete coverage to the case? (for example Joe Ruiz's cases which are uniformly covered)

Although I like the very inconsistent "used" vintage look it has.

I believe Ruiz uses the Dow treatment. If the motor never reaches operating temperature, then it is worth it.

Mon Jan 21, 2008 6:54 pm

It is called Dow 1 (or try Dow 20 if you want better than period correct.) It is SIMPLE to do. It is a wash. It is supposed to look kinda wavy with different tones or hues. You spray it on, let it sit some 10 - 15 seconds and wash with warm water. Done. It is really called a conversion coating.

Nothing special. No magic. Move along now....

Yes, kiddies, you too can do this at home.

Trick is to keep it on and I ain't telling!

Mon Jan 21, 2008 7:30 pm

r39o wrote: It is called Dow 1 (or try Dow 20 if you want better than period correct.) It is SIMPLE to do. It is a wash. It is supposed to look kinda wavy with different tones or hues. You spray it on, let it sit some 10 - 15 seconds and wash with warm water. Done. It is really called a conversion coating.

Nothing special. No magic. Move along now....

Yes, kiddies, you too can do this at home.

Trick is to keep it on and I ain't telling!

This board is all about sharing your tricks.... don't hold out..... !! Let's have the data.. need the info. :) Unless your thinking about cornering the engine coating market. Good Luck with that! :)

Mon Jan 21, 2008 10:57 pm

My coating is made in factory who makes military and aviation components. It is made by strong acids and in hot temperature.

Tue Jan 22, 2008 5:49 am

r39o wrote: It is called Dow 1 (or try Dow 20 if you want better than period correct.) It is SIMPLE to do. It is a wash. It is supposed to look kinda wavy with different tones or hues. You spray it on, let it sit some 10 - 15 seconds and wash with warm water. Done. It is really called a conversion coating.

Nothing special. No magic. Move along now....

Yes, kiddies, you too can do this at home.

Trick is to keep it on and I ain't telling!

Very entertaining! What sources are your weird ideas based on? I´ve got the Dow manual on magnesium coating where these processes are described in detail. None of them is a back yard 15 sec spray on job. All involve toxic chemicals and are high temperature baths. Besides the one used by VW was DOW-7.

Tue Jan 22, 2008 1:26 pm

Yes, the text book way is to submerge in bath at such a temperature for so long etc, etc. Then rinse with the water at such another temperature with ph of whatever. And so on. Ya, ya, I know all that too.

But, the manual further goes on and states you can touch up finished assemblies via local spray or brush application. Using that as an introduction one can apply by spray or use any local application scheme. Sure it is not as controlled as a bath. Sure it does not create such a thick uniform and controlled conversion. Yes, yes, yes, yes, it is not as perfect as following the strict manual application dictated procedures. But, we are not building space craft, either. In this case (pun intended) we get something that is close enough.

I go to the local chemical supply and simply buy the chemicals. I never stated that is was safe. For small jobs like one or two case halves doing yourself is very much something we can diy.

All I am stating is that if you want to do it yourself, you can. No magic involved.

Tue Jan 22, 2008 5:25 pm

r39o wrote: Yes, the text book way is to submerge in bath at such a temperature for so long etc, etc. Then rinse with the water at such another temperature with ph of whatever. And so on. Ya, ya, I know all that too.

But, the manual further goes on and states you can touch up finished assemblies via local spray or brush application. Using that as an introduction one can apply by spray or use any local application scheme. Sure it is not as controlled as a bath. Sure it does not create such a thick uniform and controlled conversion. Yes, yes, yes, yes, it is not as perfect as following the strict manual application dictated procedures. But, we are not building space craft, either. In this case (pun intended) we get something that is close enough.

I go to the local chemical supply and simply buy the chemicals. I never stated that is was safe. For small jobs like one or two case halves doing yourself is very much something we can diy.

All I am stating is that if you want to do it yourself, you can. No magic involved.

I buy it.... I always thought you could do it at home.. and no magic involved..... so.... come clean... give us the details.. and how to keep it on. :)

Tue Jan 22, 2008 6:29 pm

he could tell us but then he'll probably want to kill us

Wed Feb 18, 2009 8:32 am

The gold Hue that is used ( and this has been discussed somewhere else on the samba assuridly) Is a Die Penetrant die chromate Process--- It had taken me the better part of 5 years thru trial and error, and DESTROYED old used cases to get it spot on. with out divulging ANY processies, I contacted Joe Ruiz=Mr. Okrasa, and he concured that i was Spot on and that it would be best if Trade secrets be Kept at that TRADE SECRETS!!as selfish as this may seem with research, a few trips to the library, and understanding just the basics of Die Chromate penetrant Pocessies yes you too can figure it out!!!, But I wouldn't give up 5 years of diligent work , trial and error, and wasted Cases just to hand over the specific proces of the correct factory gold hue color because someone asked for it!!. Some things are best kept to your selfs. Eric (VMR) 8)

Wed Feb 18, 2009 9:35 am

thanks for sharing... :roll:

Wed Feb 18, 2009 11:26 am

I will share my trade secret: Shake can, push button. Spent 15 minutes of my life searching. And those that don't like it can pick a cheek. :lol:

Wed Feb 18, 2009 12:50 pm

Use the SEARCH Luke:

Dow 20 (Modified Chrome Pickle) was developed to provide a more uniform colored coating than Dow 1. Treatment 20 may be used on all magnesium alloys but is particularly adapted for magnesium DIE castings. Sodium Acid Fluoride 2 oz/gal, Sodium Dichromate 24 oz/gal, Aluminum Sulfate 1 1/3 oz/gal, Nitric ACid (70% Nitric) 1 pint per gallons..5 seconds to 2 minutes.

http://omnimetal.thomasnet.com/product/all-categories/magnesium-dichromate-treatment-processing-dow

http://www.wipo.int/pctdb/en/wo.jsp?IA=US2005041588&DISPLAY=DESC

http://www.google.com/search?hl=en&q=%22DOW+7%22+process&btnG=Search

Etcetera...

Wed Feb 18, 2009 5:47 pm

There goes 5 years................ :lol:

Wed Feb 18, 2009 6:27 pm

Splitdog wrote: There goes 5 years................ :lol:

Now that there's funny... :lol: :lol: :lol:

Thu Feb 19, 2009 8:33 am

r39o, ZwitterND, splitdog! Ahh if it where that easy to point click order and use, Go ahead order what r39o listed above, it's missing two very vital chemicals that completes the CORRECT chemical etching process to adhere and bring upon magnesium gold adhesion. Yep Been there done that, with alot of frustration when those so called point click and order kits didn't do squat for me or Make the correct goldish color on the case. No it took a chemical engineer + a metalergist to give me the heads up on two VITAL missing parts of the equation. Close!! But no CiiiiiiiiiiiiiGAR! 8)