News:

"The phone is a remarkably complex, simple device,
and very rarely ever needs repairs, once you fix them." - Dan/Panther

Main Menu

A method for polishing heavily pitted Bakelite that worked for me

Started by TelePlay, July 13, 2014, 12:14:46 AM

Previous topic - Next topic

Ktownphoneco

Thanks Dan.   As I mentioned, the walnut sets always seem to produce a much more spectacular shine than the black ones.    Another mystery we'll probably never find the answer to.

Jeff

TelePlay

Got a stick of DICO PCB at Ace today.

Spent about 5 minutes on the handset. Did not change my wheel, just dressed it. The PCB does indeed work better than the red compound I was using and from the picture on the far right, you can see an even more mirror like finish (pink circle).

Since the Bakelite is not smooth, was not sanded smooth (no attempt was made to do so), I don't think this experimental area will ever get any more reflective. What I have here is a highly polished irregular surface.

Had the Bakelite been sanded smooth, this would have been a mirror like finish, if this particular handset could be sanded smooth, that is.

cloyd

John,
That is an amazing polishing result and also well-documented!  Great job!  You'll think I'm a dunce, and maybe I am, but I would love to see a youtube video of the entire process.  I think that technique has a lot to do with it!
Tina Loyd
-- I am always doing what I cannot do yet, in order to learn how to do it. - Van Gogh -- 1885

Doug Rose

Jeff.....I agree with Dan....those phones are stunning. A true labor of love. Outstanding....Doug
Kidphone


AE_Collector

Quote from: cloyd on November 16, 2016, 05:59:08 PM
John, I would love to see a youtube video of the entire process.
Tina Loyd

Well, John would have to do a little cleaning in his workshop before any film crew is going to move in to do a YouTube there....



Excellent work John and Jeff, you are getting me thinking about needing a buffer again myself. I have thought about it many times over the years.

Terry

Ktownphoneco

What's wrong with John's shop ?     A couple of air fresheners if needed, and it's good to go !

Jeff

tipnring

So I have been buffing up my bakelite phones using the Brasso method described in this post..I also found out that your buffing wheel doesn't do any good for plastic reciever caps.  I was buffing a NE G1 handset with the caps on, and I got a little to close to one of the caps and melted one edge.. you can smell it right away. So keep your buffer on the bakelite.... I know Jeff is having a good laugh....Dennis.

Ktownphoneco

Dennis  .... I wouldn't laugh at that !     Well, OK, a little bit.    My buffing wheel spins at 1725 rpm.      I use flannel buffing wheels and a string buffing wheel.    Here's the Reader's Digest version of buffing plastic :   sand whatever your going to polish, using wet / dry sand papers, in water.    John has the proper sequence insofar as grit is concerned.    I end the sanding with 2500 grit wet / dry.
John uses 2000 grit which is fine.    There's no big difference between 2000 and 2500.     Use a soft flannel wheel, followed by a string buffing wheel.    THIS IS THE IMPORTANT PART WHEN POLISHING PLASTIC, and which you just discovered.  "KEEP THE PLASTIC MOVING" AT ALL TIMES".   "DO NOT STOP IN ANY ONE SPOT - EVER".     If your polishing a plastic handset, like a "G" series, polish the handle portion, and the caps separately, not as one piece.     Use a plastic buffing compound, like DICO PBC.    Eastwoods also sell a plastic buffing compound in large tubes, but I've found that it's just not as good as DICO's PBC on Bakelite.     But it's just as good on plastic.
Coincidentally I just polished a sanded 2500 series Western telephone housing today on my buffer.   It came out just fine.   I'll post some pictures later showing what it looks like.     I'm doing the handset next.    Once it's all together, I'll take some pictures.    Just to go over buffing plastic :   "DO NOT STOP IN ONE PLACE".    Keep the part moving, and don't lean into the work piece.     Just a light pressure, back and forth, until you get the shine your looking for.

Jeff

Ktownphoneco

Dennis   ... I should have included this in my last post.      When I say keep the piece moving, I mean fairly quickly, not in a slow motion.    The other thing I should have mentioned, was that I wasn't blessed with some sort of "divine plastic polishing" abilities.    I overheated several pieces of plastic telephone parts when I was learning the technique.      Most everybody goes through that phase when learning to buff plastic.    Don't be discouraged, and don't give up.    It's all about technique.    Practice on something like a black plastic "G" series handset that are a dime a dozen to replace.

Jeff


tipnring

I need a slower speed buffer for one.. I am looking on line now (Christmas is coming)  Thanks for the advice..got lots of NE handsets to practice on. I haven't really moved onto plastic yet as I know it is trickier. Dennis

TelePlay

I'm using a 3450 RPM buffer so the speed at the surface of an 8" wheel is about 82 MPH.

Jeff's buffer doing 1725 RPM has a surface speed of an 8" wheel at about 41 MPH

Yes, I've burned plastic with the faster buffer and it burns much easier. That's why I said to always buff off of an edge. If the wheel catches an edge, the plastic piece not only tries to dig into the wheel but also since the edge is a fine point and not a broad surface, it melts or burns a lot faster.

I have burned flat surfaces as well with my faster buffer and that's Jeff's point about keeping the piece moving. A quick way to learn how to do it is to just barely touch the piece to the wheel as you keep moving the piece. Moving it with the direction of the wheel creates less friction and the wheel does not try to pull the piece into it. If you move the piece against the rotation, it will heat up faster.

So, just touching the plastic to the wheel, right after you remove it and check the temperature with your finger. That will teach you how much pressure you can put on the wheel and for how long.

Having a fast buffer, I can only just barely touch the wheel to get a good shine without buffing. On the other hand, I can push a Bakelite piece into the wheel to the point of deforming the wheel and hearing the motor start to slow. That's a lot of pressure and I do that until the Bakelite gets hot, as I said, about 160 F.

One nice thing about burning plastic is that it can be sanded off and brought back to a nice shine without any notice of the slight amount of plastic that was burned.

One final point is HANG ON TO THE PIECE WELL AND HAVE A STEADY STANCE. Letting a piece get ripped out of you hand due to not the best stance is not good. Be prepared when you take the plastic to the wheel and take it slow. And watch where you are moving the piece. Doing the side of a 500 is easy until you run one of the ears into the wheel - been there, done that, much more careful now. It's a lot less time to do it well the first time, without having to take time to resurface burned areas.

I used the DICO PCB on my soft plastic pink 500 yesterday and got a much improved shine (without burns). Now I'll have to get some 2500 paper. I have micro mesh but that's not practical on Bakelite.

Hope this helps get an understanding of what can be done and the perils encountered in the learning curve. This is the topic that was posted in 2012 that got me started, and the information posted by kleenax shows what can be done with a buffer and plastic.

http://www.classicrotaryphones.com/forum/index.php?topic=8217.0

Ktownphoneco

Good point John, about a buffing wheel "grabbing" things out of your hand, and one I'd forgot to mention.      I've made what Western and Northern called apparatus blanking plates for the dial openings for 302's, 500 rotary dial sets, and for the more or less square openings on touch tone sets.     It's guaranteed to stop any buffing wheel from catching the dial opening and firing it across the room or garage.     I learned that trick the "hard way".


Jeff

TelePlay

Found this chart which explains or shows buffing compounds and their use. This only describes "grit," not buffer speed. The very top and bottom lines of the chart come into play with phone work. The lowest grit PBC (blue) is recommended for everything on the chart.

WEBellSystemChristian

I use Tripoli Compoud for Bakelite polishing on my buffing wheel. It seems to work pretty well, but the plastic needs to be sanded with a higher grit sandpaper first.
Christian Petterson

"Whether you think you can or think you can't, you're right" -Henry Ford