Foam anyone? A little info please.

[PlayerElectone]

You Hammond experts out there will probably have the answer in a NY minute. Over the years, I had probably 8-10 Hammonds of different models. I currently have an A-105 that's in almost perfect condition, but I want to sell it. I posted it, and a guy answered the ad. He asked what year it was built. Going by the serial number, it was somewhere around 1965 - 1966 or so. He said, "No thanks. It has foam." I left it at that, but I have NO idea what he means. Apparently it has something to do with the construction, but I'll be dipped if I know what he's talking about. Could someone please educate me? Thanks.

[ShadyJoe]

At some point Hammond started replacing some of the felt around the manuals with foam. This foam sometimes becomes gooey and starts dripping onto wires and causes problems. The problem, as I understand it, is caused by heat and/or humidity. So an organ kept in good conditions, little heat and humidity, wouldn't face the problems. The foam can be replaced but it is a bit of work.

Someone else will fill in the missing info.

[tiredoldgeezer]

Of course, everyone has their own story, but I understood that the foam decomposes into goo. This decomposition is caused by petroleum products, of all things, which would include, yup, Hammond oil or the vapors therefrom.

The goo is no fun. It's a sticky, nasty mess, and I've touched it and turned my fingers into a printing press until I got it cleaned. It's been said to eat through the insulation on the key contact resistance wires, however I've never seen this particular malady.

And yes, as said, it can be replaced (no biggie) and the black goo cleaned off (more trouble) and everything be fine and dandy.

Years ago, when Hammonds were more plentiful, it was considered 'informed' to avoid a 'foam Hammond'. Nowadays, as availability has changed, I would not. I'd take it as-is and deal with the foam. But everyone has their priorities.

[DGMCRC]

I have de-foamed 5 of my Hammonds - 2 B3s and 3 A100s. I've been extremely fortunate to have found no deterioration of the resistance wires. I experienced two distinctly different types of foam. One is more of a sticky gooey substance and one is more dry and flaky. Both will cause damage to the wires. In the best case scenario, the foam will have stuck to the edge of the loom for the wires. Worst case is a foam strip pressed into the loom causing deterioration. I very carefully remove it and clean the residue with goo-gone. It seems to remove the residue safely and completely without affecting the coating on the wires.

[peterb_2795]

@PlayerElectone: I think that many of us will have come across the foam problem at some point (assuming that we have worked on a few consoles). I remember that it was only some 15 years ago when I discovered my first "gooey foam" story. The lower manual had been badly affected (120 resistor wires eaten through and an equal number affected to a lesser extent). At that time, there still appeared to be some controversy about the very existence of this issue due to the fact that many of the experienced Techs hadn't ever come across this problem in their area of operations.

I certainly discovered it on my first console and found that it was not too difficult to make a new tail using wire wrap and an appropriate resistor and connect through to the correct frequency lug. The problem starts to test one's patience when you replace all 549 wires because of extent of damage. Not for the faint of heart for sure. However, what do you do when the cost of acquiring and shipping a full manual from the US costs about the same as buying a decent C or B-3 in the US? Costs of shipping and import taxes, handling etc become fairly prohibitive when shipping to Oz. Given the acute shortage of consoles in Australia, it drives us to take some pretty radical actions to solve the problem ... see attached pics.

In regards to the manual with the 549 resistors soldered into place, I still haven't completed the wiring 10 years later as I will drag it out, complete a row and then find myself reminding me how crazy I am to be doing this. Console then goes back to storage for another year!... It will be finished one day and will then be something of a unique (if not dumb) repair ... lol

Would I take a chance on another console from same era (mid 60's) knowing that it will be a foamer? Anwer is Yes, of course, and then deal with whatever one finds inside....

The age/model/location/foam issue would of course be a factor in the price negotiation. In fact, in my last C-3 purchase, I had a discussion with the seller about the very problem of resistor wire damage and we came up with a two price agreement based upon whether we found less or greater than 20 damaged resistor wires once the manuals were opened up. It seemed a fair way to approach the problem.

HTH

[gtojimmy]

Peter, I assume the resistance is one value, as you're buying resistors in bulk? I suppose I could look up the color codes, but I'll just ask: What is the resistance value?

[Jaim]

You will need to inspect the covers on the manual looms. If there are rivets, then you have felt. No rivets (just holes), foam. I have seen 1965 consoles with one felt and one foam manual. As was stated, heat and humidity play a roll. I fixed a C3 in SC which came out of a church which had 20 broken resistance wires, Since I moved north, I have found that the foam isn't as gooey if you get it cold. Attached is a picture of the rivets which I found online. .

Jim

[peterb_2795]

Peter, I assume the resistance is one value, as you're buying resistors in bulk? I suppose I could look up the color codes, but I'll just ask: What is the resistance value?

No, not the case. all resistances are selected as per the tapering charts (ref: Carsten Mayer taper chart) with a couple of resistance modifications to match the original manuals...

[PlayerElectone]

You guys are amazing. Thanks for the education. Like I said, I had no idea why the foam was such an issues. This particuar console is in great shape and plays like new. But who knows what's hidden underneath? Thanks, again for the info.

[David Anderson]

There were even a few transitional organs (I've seen one in person) in 1963/64 that have one foam manual and one felt manual.