Hello All,

I just finished glass beading the Brake booster down to the bare metal and I am not sure about the original finish. Does anybody know if it was gloss black or had a % of a flattening agent added?

The small amount that was left looked like gloss but after 35 years it is hard to tell. Any help would be appreciated.

Thanks, Jeff

Hi Jeff,

I don't have any good leads on the "correct" finish for the booster. Humble's book and the FSM are not much help. I had been using Eastwood Products for the black components, and to me it looks like a higher gloss than the Chassis Black which is a 60-75% gloss, and definitely glossier than Underhood Black (10-20% gloss). So I ultimately went with an 85% Gloss Black. Not sure if it's right. Here are some pics so you can make a better evaluation/informed decision...

Sorry if the detail's bad. I can try to get some better pics, but getting a good photo of something black can be tough.

Thanks and good luck!

Steve

Thanks xray,

That looks like pretty much the same finish that was left on the original unit. Was the sticker in that nice condition or did you get a replacment somwhere? Mine is mostly shot.

Jeff,

Thanks. I got lucky with the sticker as it's the original. There was some discussion earlier about replacements, but I can't come up with the thread. IIRC, a suitable replacement has not been made. Do a search, and there may be more info I'm unaware of...

Also, search the photo archives here for brake booster, brakemaster cylinder, firewall etc. You may get some other examples to help out.

Good luck,

Steve

PS: My BMC is not original....

I recall mine as being fairly glossy, maybe like the 85% gloss, I'd guess. I didn't drive the car to work today, I'll try to verify that later tonight.

Thanks to everyone for helping. All the aluminum parts turned out great from the glass bead cabinet.

Jeff

I have a new NOS booster still in the box from Nissan, for reference, that is not high gloss. It is slightly less than high gloss. I would gauge it to be about 90%. If you were to apply polish to this booster it would bring the luster to a full gloss look. So I hope this gives you some reference. If you are spraying it try to avoid making the final coat a wet one. By putting it on a little drier it will keep the gloss down. I hope this helps. I would take a pic of the booster I have but I am afraid the flash will distort it but if you need on let me know and I will try.

Bob

I'll second that - the booster in my low-miles red 240Z is more of a semi-gloss or satin finish. It is very smooth, but not high-gloss. I've painted a few parts with some Satin Black from Griot's garage that is very close.

Bob, Arne:

Pics please. I thought mine (as I stated above) wasn't quite right and if there's a NIB booster I'd like to see its finish....

Anything you can post would help all of us out.

Best I could do. Took several shots at varying exposures to try to capture it. But note the reflection of the red firewall and hoses. Glossy enough for there to be a reflection, but not glossy enough for the reflection to be sharp.

Arne,

Thanks for the pic. It's a tough call for sure, but I'm thinking my coating is too glossy...I'll have to pay attention at a car show to confirm.

Steve

I wonder if I could paint it with a gloss black and then put a wet coat of Eastwoods diamond clear satin over it to take some of the gloss off? Ill try it on a scrap piece of metal and see what happens. If it doesnt turn out right I will have to get a pint of Gloss Black and a flattening agent and use my small gun to get the 85-90% gloss.

Jeff