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Re: Does the weight of an Electrola changer platter matter?

Posted: Fri Apr 05, 2019 12:48 pm
by maginter
Skihawx wrote:I would think a machinist could drill a larger straight hole, press fit a rod, and re-drill. I would hate to see good original turntables replaced with copies unnecessarily. I hope keeping the original parts for any new owners would be part of the process. That has not always been the case for machines I've purchased from others. Doing what you want to a machine you own is understandable. They are our own personal property. "Since you were asking questions." Buying every machines that comes on the market and performing ones personal restoration practices every machine that is kind of disturbing. I guess there will be some original machines out there. I would rather tolerate a little wobble, after all it is over 90 years old. BTW, If to maintain momentum is the goal, which makes perfect sense, it is not the total weight but the weight distribution. I know we all have our opinions and I felt it was time to share mine. 58

I absolutely agree with Jeff!!! I have had several that I have plugged and re-drilled to flatten the spin. It is easy to do and does not compromise the platter, machine or performance.

Mark

Re: Does the weight of an Electrola changer platter matter?

Posted: Fri Apr 05, 2019 1:30 pm
by Victrola-Monkey
Mark,

As I previously mentioned, my machinist did resolve one warped platter in this manner. However these last 3 platters I pushed off to my last three type-1 changer machines (the VE 10-70s) are warped in such a way that this solution will not work. Additionally the cost to have this done is more than that to create new platters. Also as I previously mentioned, I will keep the original platters with these machines so that future owners can do with what they want. Meanwhile perfectly flat ones will allow the machines to operate completely perfect. This plan should do nothing to hurt its value, it’s historic preservation, or anyone’s feelings.

Re: Does the weight of an Electrola changer platter matter?

Posted: Fri Apr 05, 2019 3:34 pm
by PeterF
I pulled out my original platter, and the all-aluminum one that I had machined many years ago, for comparison. Here are photos.

Interestingly, it turns out that the aluminum one is considerably lighter, about ¾ of a pound and a 22% reduction. But it looks like Victor tried to lighten theirs if one looks at the underside (drilled-out holes with no function, perimeter lip to give the appearance of a thicker platter) so perhaps the weight loss is advantageous. But the proof is in the pudding, and the thing has worked just fine for more than 20 years now...and is certainly more stable dimensionally over the long term.

Now for some unsupported guesswork about the effect of a lighter platter. Ferraris and racecars have lightweight flywheels to enable quicker revving. Thus we might expect this one to allow easier speed fluctuations, but since speed is controlled by a governor it means that the platter would adjust more quickly to the governor's inputs. So that puts speed stability onto the governor's performance and not the platter. That's my theory and I'm sticking to it, until someone who remembers their physics better than me alters the conclusion. Extra points for citing the right hand rule.

Bob Fisher was the machinist, and nobody knows how old he was when he passed. He was retired from the Lawrence Berkeley Lab around 1990 or so, and we also know he served in the Merchant Marine during WWII. So that would make him in his mid-70s when he made this platter for me. Old guys rule.

Re: Does the weight of an Electrola changer platter matter?

Posted: Fri Apr 05, 2019 4:36 pm
by Victrola-Monkey
Peter,

Thanks so much for posting your experience with the aluminum platter and providing pictures, as well as doing the weight comparisons. With the aluminum one weighing 2.6 lbs. and the original weighing 3.34 lbs, that is close enough for me to feel confident about going ahead with a prototype. Not sure why my math was off, maybe a cubic inch of aluminum weights more than 1.57 ounces. I took my first search result as gospel.

I like your analysis regarding the weight’s interaction with the governor. I think that’s a great point.

I would like to emphasize to folks that a changer machine is more sensitive to a warped platter than a single play machine. The warp can play havoc when the Lift Ring goes to lift the record off the platter and then attempting to get it down the record shoot cleanly.

Re: Does the weight of an Electrola changer platter matter?

Posted: Fri Apr 05, 2019 4:43 pm
by PeterF
I think I’ll take some simichrome to it before putting it back into service...

Sure is beautiful. Check the fine detail.

Re: Does the weight of an Electrola changer platter matter?

Posted: Fri Apr 05, 2019 11:54 pm
by electrolaman 64
I understand what Wayne is saying about a really warped "turntable" and yes a re-drilling of the center hole will not correct that problem. A proper reproduction is OK in my book as long as it looks absolutely correct on top and has the gold plating around the rim (or something convincingly similar looking). I have re-plated rubbed off gold plating in the past quite successfully with a Texas Plater's Supply brush plating kit. They have Copper, Nickel, brass and GOLD.

I know that Carsten Fischer has had the replacement turntables already made and still has some in stock. They have not bee plated yet though.

Carlton Smith
electrolaman 64
Indianapolis, IN

Re: Does the weight of an Electrola changer platter matter?

Posted: Sat Apr 06, 2019 12:16 am
by PeterF
What’s the nature of Carsten’s replacement platter? What material, cast or machined, etc?

Re: Does the weight of an Electrola changer platter matter?

Posted: Sat Apr 06, 2019 11:13 am
by Victrola-Monkey
Carlton,

I called Texas Plating Supply Company and unfortunately he no longer offers a gold plating kit, though he still offers the other kits. He said the gold plating kit was a loosing proposition for him.

I emailed Carsten about want he might be offering regarding the replacement turntables. I await his response.

Re: Does the weight of an Electrola changer platter matter?

Posted: Mon Apr 08, 2019 7:36 pm
by MarkELynch
Wayne, Peter, Carsten, Jeff and others:

Some time ago when first repairing the First Style Victor changers I also ran into the warped platter difficulties. I realized that the warped ones were cast from the dreaded Alumac pot metal and the perfect ones were made from cast iron. Photos of both types are below. The weight of both is approximately the same, I’ll check later when my digital scale is returned. The cast ones, I’m addition to being magnetic have machining marks on the underside, the Alumac ones are smooth so they are easy to spot. My presumption has always been that the early ones were cast iron and the later ones are potmetal; the casting die wasn’t ready yet...

Like the others here , I had some success by turning the potmetal turntables on a large lathe to bore a new oversized center hole on center, a machined aluminum bushing was pressed or installed with green Locktite, the kind needed for cylindrical fits like this. The playing surface was faced as best possible but it still retained a bit of warp. Some turntables responded well, others were unusable.

Along the way I had some replicas made like Peter and Carsten did and that Wayne is preparing to do. At the time the premier phonograph machinist was, Bill Ptacek, so I sent an original cast iron turntable to Bill and he returned three exact duplicates. Bill turned them on his lathe from an 8” diameter bar of gray cast iron, see the photos. He captured every detail except the gold plated rim. The Texas Platers supply at the time offered copper and gold brush plating kits which worked pretty well, a coat of Nikolas clear instrument lacquer protected the plating. The price was quite reasonable and the workmanship superb.

See the photos below. Pictured are both the cast iron and pot metal turntables as well as Bill Ptacek’s replica. Bill also made several fabulous Tin Foil replica machines perfect to the last detail, see the link.

Bill unfortunately died in a boating accident in 2004, please see Rene’s tribute to Bill in this link.
http://www.edisontinfoil.com/bill/ptacek.htm


Mark
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Re: Does the weight of an Electrola changer platter matter?

Posted: Tue Apr 09, 2019 3:52 pm
by Victrola-Monkey
Mark,

Very cool. Thanks for the enlightenment on the fact that there were two different turntables that used two different materials on these 1927 Victor changer machines. A magnet is a great way to quickly identify if a turntable is cast iron (ridge rings on the underside) or pot metal (smooth bottomed). These pot metal turntables that you say are Alumac actually have a “Dura-Zink” logo on the bottom along with the number “19707”. The cast iron weighs 3 lbs. 11 oz. while the pot metal is a hair lighter at 3 lbs. 8.5 oz. I’m gonna have to add a link to this posting on my two other posts that discussed comparisons of these changer machines, for future reference and searches.

Also thank you very much for sharing the link on Bill Ptacek. What a great man he was and what a wonderful impact he made on the phonographic community.

-Wayne