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EeBe4
02-06-2014, 08:12 AM
Forumites,
I have purchased sand cast bronze hardware I'd like to polish to match the "shiny" bits I also have.
What process do you recommend to achieve this? File, sand, wire brush, compound?
Thanks!

Peerie Maa
02-06-2014, 08:13 AM
Got any pictures so that we can see how rough they are?

Thorne
02-06-2014, 10:01 AM
For the really rough stuff I've used a palm sander, followed by a wire brush wheel on a grinder. Wear a faceshield for the latter process! Comes out a lovely, buttery gold color...

EeBe4
02-06-2014, 10:45 AM
Thorne, brass wire brush? Thx-

James McMullen
02-06-2014, 10:50 AM
Steel wire brush, followed filing, sanding, more sanding, yet more sanding, even more sanding, and eventually polishing on buffing wheels of progressively finer compounds until the end of time.

Or you could just get it smooth-ish enough, and then let it get a patina. That's generally my favorite, when I can manage it.

Jim Ledger
02-06-2014, 11:08 AM
A belt sander can be put to good use on flat surfaces. A stationary belt sander is even better. Ther's a one inch wide belt sander out there that can go around curves and get into tight spaces. A die grinder with abrasive wheels will do a lot of work for a small outlay.

This is a belt sanded finish. It could be polished further but because it's an underwater fitting there's no point.

http://i104.photobucket.com/albums/m193/searover1916/Rudderhanging28jpg.jpg (http://s104.photobucket.com/user/searover1916/media/Rudderhanging28jpg.jpg.html)

EeBe4
02-06-2014, 11:13 AM
https://lh4.googleusercontent.com/-6Xmo2sJ2Tz4/Uurr4w2ZpKI/AAAAAAAACO0/SUI1EmdUHIk/w472-h632-no/IMG_7019.jpg
Thanks for the input guys. I'm not after a mirror finish, just a closer match. Off to the garage-

Jim Ledger
02-06-2014, 11:21 AM
Oh, yeah, if you belt sand bronze you'll need to be wearing heavy gloves...and even then you will want to do several pieces at once to allow for some cooling.

Thorne
02-06-2014, 11:51 AM
Steel wire brush, followed filing, sanding, more sanding, yet more sanding, even more sanding, and eventually polishing on buffing wheels of progressively finer compounds until the end of time.

Or you could just get it smooth-ish enough, and then let it get a patina. That's generally my favorite, when I can manage it.

The Don of the Mizzen Mafia is again correct, steel wire brush. These tend to fire bits of wire out in all directions, hence my recommendation for a faceshield -- and add a heavy shop apron to that, willya?

Canoeyawl
02-06-2014, 11:53 AM
Flap wheels...

http://ecx.images-amazon.com/images/I/51QPczJRqKL._SL500_AA300_.jpg

http://www.abrasivesales.com/images%5CFM.jpg

Gerarddm
02-06-2014, 12:12 PM
Somewhat analogous, I had a set of Cromodora alloy wheels for my Fiat Spider 2000 that I had sandblasted, then spent countless (!) hours getting down to a high polish. Due to the convoluted pentastar design, most of the work was done by hand and Dremel using flapped wheels. Came out beautiful in the end, but gawd what an amount of work to get them to that state. I Flitzed them every couple of weeks to keep them like that.

csmead
02-06-2014, 01:39 PM
http://i104.photobucket.com/albums/m193/searover1916/Rudderhanging28jpg.jpg (http://s104.photobucket.com/user/searover1916/media/Rudderhanging28jpg.jpg.html)
How is this beautiful piece of hardware attached to the wood?

Jim Ledger
02-06-2014, 01:51 PM
How is this beautiful piece of hardware attached to the wood?


Thank you for the compliment.

It's riveted on with 3/8" bronze rod. If your interested in seeing it done you can look here...

http://forum.woodenboat.com/showthread.php?79099-Lofting-the-Brewer-catboat/page34

If you're intersted in seeing the fitting and its mates being cast you can look here...

http://forum.woodenboat.com/showthread.php?88357-Casting-catboat-rudder-hardware&highlight=




(http://forum.woodenboat.com/showthread.php?88357-Casting-catboat-rudder-hardware&highlight=)

Jim Ledger
02-06-2014, 01:58 PM
The boatbuilders friend, a 4 inch angle grinder with a sanding disc can remove a lot of excess metal fast. If used with a light touch it can get into a lot of corners and dress outside curves quite well. It quickly gets past the pits and makes final finishing less arduous.

Welding supply shops have a large variety of special discs that can be used to advantage,

PeterSibley
02-06-2014, 05:33 PM
The boatbuilders friend, a 4 inch angle grinder with a sanding disc can remove a lot of excess metal fast. If used with a light touch it can get into a lot of corners and dress outside curves quite well. It quickly gets past the pits and makes final finishing less arduous.

Welding supply shops have a large variety of special discs that can be used to advantage,

One of those flap discs for your grinder is a very good tool for the job then a felt buffing wheel and compound for your stationary grinder .

EeBe4
02-06-2014, 06:20 PM
Awesome gents! I'll post a pic of the final. Took some courage to hack off the pintles from the rudder gudgeons, but it is done. They were 1/2" diameter and I didn't want that much material removed from the Stern gudgeon blanks that I'm polishing. I had considered filing the pintles down, but spinning that hardware neater a file made me gun shy.
Holes are drilled now for a 5/16" rod. I think it will all work fine. Appreciate the help-

Bob Cleek
02-06-2014, 11:09 PM
When you are done, you'll know first hand why polished bronze hardware is priced like jewelry!

Garret
02-06-2014, 11:24 PM
A bit late to the party, but I'll second the die grinder. Adjust grit to how rough it is, get progressively finer & finish with the aforementioned steel wire wheel. Of course, eye protection far all of this.

One of these:

http://www.abrasivesaver.com/images/products/11090.jpg

Using discs (though finer than these):

http://i.ebayimg.com/t/50-pcs-2-ROLOC-SANDING-DISCS-FOR-DIE-GRINDER-A-O-/00/s/MTIwMFgxNjAw/%24%28KGrHqZHJBkE63VtkvRHBO7e7oO%288w%7E%7E60_35.J PG

rob
02-07-2014, 03:49 PM
Norton makes deburring wheels in various grits. They are like a high density rubber bonded grit, flexible enough to generally avoid cutting in like a belt can on its edge.
They can also be shaped to fit odd profiles
They are fast and very useful, but a little spendy. However, after spending hours with files and sandpaper they are viewed in a simply wonderful light.

BETTY-B
02-07-2014, 04:18 PM
This thread needs more pics. I did these little babies with a combo of palm sander and finished 'em off on the buffing wheel:

http://i32.photobucket.com/albums/d10/Bridgedeck/BETTY-B/Bronze/betty157.jpg (http://s32.photobucket.com/user/Bridgedeck/media/BETTY-B/Bronze/betty157.jpg.html)

http://i32.photobucket.com/albums/d10/Bridgedeck/BETTY-B/Bronze/betty173.jpg (http://s32.photobucket.com/user/Bridgedeck/media/BETTY-B/Bronze/betty173.jpg.html)

http://i32.photobucket.com/albums/d10/Bridgedeck/BETTY-B/Splash2008/P1011121.jpg (http://s32.photobucket.com/user/Bridgedeck/media/BETTY-B/Splash2008/P1011121.jpg.html)

Garret
02-07-2014, 04:32 PM
Love that curved transom! Nice dog too....

BETTY-B
02-07-2014, 04:49 PM
Love that curved transom! Nice dog too....

Me too, Garret!:)

One more at the install:

http://i32.photobucket.com/albums/d10/Bridgedeck/BETTY-B/Bronze/P2221032_zps190aa944.jpg (http://s32.photobucket.com/user/Bridgedeck/media/BETTY-B/Bronze/P2221032_zps190aa944.jpg.html)

Gerarddm
02-07-2014, 05:38 PM
His body language tells me that is a happy dog to be on the water. Nice.

Oyster
02-07-2014, 05:41 PM
One of those flap discs for your grinder is a very good tool for the job then a felt buffing wheel and compound for your stationary grinder .
Peter,
I don't know if everybody has seen these, they work good on inside radius's with out gouging as bad as a flat flapper disc and won't wear out the outer edge of the disk near as fast.

Royce
http://i1212.photobucket.com/albums/cc450/oyster9/image-44.jpg (http://s1212.photobucket.com/user/oyster9/media/image-44.jpg.html)

stewart711
02-07-2014, 06:35 PM
This thread needs more pictures of that lathe you have.