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Does anyone know if anyone sells DASHPOTS for an Orthophonic Credenza? Mine work for about a day after I do the suggested repairs, then they lose all power. I see cracks up near the top of each cylinder. Could that mean they are leaking?

Cracks near the top shouldn't necessarily be a problem. Basically, the dashpots are just bicycle tire pumps in the way that they operate. There are adjustments at the bottom of each that regulate how fast the air can leak out, or in other words, how fast the lid can drop. Those regulators have a lock ring that you need to back off. Then, screw each regulator in, (clockwise), just a bit to decrease the air flow rate. This should cause the lid to lower more slowly.

Of course, it is also possible that the pump leathers are shot... Also possible that the cracks are a problem, but being near the top, while the build up of air pressure is near the bottom, leads to believe not.

Here's a very recent related thread:

http://forum.talkingmachine.info/viewto ... =2&t=22770

I just rebuilt my dash pots according to the two-part video on Youtube. I did a dumb thing when I reassembled mine. I forgot to thread the struts through the slots in the mounting supports at the top of the dash pots. So I had to disassemble them to thread them through the slots. Then I made another mistake when installing them. I put both dash pots in backwards so that you could not raise the lid all the way. I think the way to install them is short side of mounting bracket forward and long side facing the back. If you pull the struts out all the way, it will be obvious which way to install them. Mine have cracks at the top also, as did the man in the video. I noticed that when I release the lid from the ball bearing detents, it falls about 9 or 10 inches and then slowly creeps down to the cabinet, just like the guy's in the video. My tech suggested that the reason it probably falls at first is because the cracks at the top of the cylinder prevent a vacuum. He said if I wanted to correct that to rough up the crack with sand paper, clean with mineral spirits, and J-B weld the cracks so they prevent air leakage.

Helpful video and good follow-up suggestions by Marc, but it made me nervous when the gentleman used the pipe wrench directly on the cylinder.
I was waiting for it to crack.

Gene

Yes, the pipe wrench is risky, but those valve nuts are usually on very tight. I guess a better way would be to hold the cylinder in a wood vise, or protect the cylinder with wood or thick cloth, and use a 1" wrench on the nuts. Or, at least put a heavy cloth around the cylinder before using a pipe wrench on it.

Be VERY careful applying a Stillson-type pipe-wrench... the cam-action of the moving jaw can crush a pipe before you know it...

De Soto Frank wrote:Be VERY careful applying a Stillson-type pipe-wrench... the cam-action of the moving jaw can crush a pipe before you know it...

Not to mention, put nasty (and permanent) marks on any surface gripped by the jaws.

They don't call it "pipe" wrench for nothing.... These work great on galvanized steel (often mistermed "lead pipe") pipes, as in plumbing; in such application, it usually doesn't matter if the pipe surface is scarred.

It may be possible to use a strap wrench on the dashpot cylinder. These will not mar the surface, if used properly. Horror Freight sells an affordable set of these (2).

I realize after reading this thread again that nobody answered his original question. Does anyone sell Credenza dashpots? If he means new ones, I don't think so. Used? Maybe George Vollema might have them, but they might also have the cracks at the top and might also need rebuilding.

I bought two from George Vollema several years ago, and got one additional one on eBay with a bunch of orthophonic parts. The threads are stripped on the top, or I would offer it.