Please help troubleshooting my vacuum press

[akthoma]

Sorry for all my posts, but I'm at a loss of what to do. I've been having issues with our HotPress not consistently getting a vacuum. I've done a series of trouble shooting tests and then eventually I did finally find a technician who was coincidentally in the area (he lives many states away) to come and service our machine. We thought it may have been one of the clamp/latches that was loose that was causing issues, so he tightened those. Of course every time we tested the machine while he was here, the machine worked fine.

Days later when I tried it on my own, it wouldn't pull a vacuum, so I took out everything (foam board, release paper and release board), and it will get a vacuum fairly quickly after that. Then sometimes I can put everything back in and will get a vacuum, but other times it won't work. When I do get a vacuum, it gets up to 28.

I tried several tests yesterday, I left the materials in the machine and didn't open the lid between tests. Two times in a row the press would get a full vacuum, but the third time it took about 4 minutes. This was without touching anything inside or opening the lid.

I've checked the gasket many times and sealed up every area I thought was loose.

Any ideas on what could be causing this? The technician that worked on the machine is many states away, and I don't know the next time he'll be out here. Also, he doesn't work on HotPress machines but was nice enough to look at ours, so if we needed parts, we'd have to order them and have him come back which who knows when that would be.

The press is 17 years old. We haven't ever changed the diaphragm or the gasket, but it's not a high use machine. Normally when we had issues it was always that the gasket had loosened in some areas. Do diaphragms wear out and have issues even without holes? If so, how do I know it's worn out? And how do I know when the gasket needs to be replaced?

Unfortunately I'm not handy, so I will have to hire somebody to work on these things, which is fine, but I would like to know for sure what the issue is, and unfortunately there's nobody in my near area who works on these things.

 

[tedh]

I’ve got a smaller, older Hot Press, and I’m in the same situation. I’ve checked out the seals, the air lines and I even took the diaphragm out and patched what I thought were a couple of pinholes. Can’t get more than 17 psi. Looked at the air pump, and can’t find anything there. I’ve stopped using it.

 

[akthoma]

I’ve got a smaller, older Hot Press, and I’m in the same situation. I’ve checked out the seals, the air lines and I even took the diaphragm out and patched what I thought were a couple of pinholes. Can’t get more than 17 psi. Looked at the air pump, and can’t find anything there. I’ve stopped using it.

Oh no, I'm sorry to hear that. That's very frustrating especially since you know how to check the machine and repair things.

Up until now our machine has been great. I'm not sure I'd get another one, because it seems like nobody works on these, and DryTac who we purchased it from doesn't even offer support for the machine anymore.

Do you know if there are any manuals or videos that show how to take out a diaphragm and either put it back in or replace it? One of my colleague said she would be willing to try and do so if there was a good manual. I can't find any information on how to do so, and the manual for our machine only has basic information without any information on how to change the diaphragm.

 

[alacrity8]

As far as I know, clamps shouldn't be needed to get a vacuum, they are often added to help correct another issue.
At least that is how it was with a press I used at another shop.

If the diaphragm is good, I would wonder if there is some problem with the air pump, or between the pump and the press.
Does the pump seem to be working normally? Is there enough space around the air pump?
Are the connections good between the pump and the press? You might have to lift the back of the press to see that.
If there is a felt like material inside the press, on top of the suction spots, perhaps it has become clogged with dust/glue.

I have one at my shop that I need to find the time to replace the gasket

 

[Jim Miller]

Have you reset the lid? Have you used the recommended procedure to check for internal leaks? Here are snippets from the Drytac Hot Press Operator's Manual, which is also attached in case you need it:

To check for internal leaks:

 

[tedh]

Well that’s interesting. I haven’t seen that manual, in spite of looking everywhere online. And I didn’t know there was a pump filter. Too bad they didn’t include a diagram of where that filter is located.

Thanks for posting it, Jim. I’ll let you know if I find my issue.

 

[akthoma]

Have you reset the lid? Have you used the recommended procedure to check for internal leaks? Here are snippets from the Drytac Hot Press Operator's Manual, which is also attached in case you need it:

View attachment 50515

View attachment 50514


To check for internal leaks:

View attachment 50516

Thank you for the suggestions. I just did the bookmark test, and there's an area in the back right where I can easily slip the paper out of the lid. So I'm assuming the lid needs to be reset, although I'm not handy at all and wonder if I can do this. The press is fairly close to the wall, but I think I can still get back there.

If the lid is only "loose" on the right side, does that mean I would only need to adjust the hinges on the right side? Sorry, I'm super ignorant with these kind of things.

 

[Jim Miller]

Follow the instructions and reset the hinges on both sides. That's the only way to assure that the entire perimeter of the lid will seal properly under full vacuum.

If you need to move the press to access both hinges, then leave it where you moved it. Any change of its position could mess up the lid alignment.

 

[Bruce Papier]

Before you do all that, check to make sure the table the press sits on is flat. If a corner of the table tilts just a little bit, it can cause the gasket not to seal.

 

[akthoma]

Before you do all that, check to make sure the table the press sits on is flat. If a corner of the table tilts just a little bit, it can cause the gasket not to seal.

Is setting a level on the top of the press when the lid is closed enough to tell if the table is flat as long as the level shows that it's level?

 

[Jim Miller]

I suggest checking the level of the base, not the lid. And since corner-to corner deflection/twisting could foul the seal, check all four sides and the diagonals.

 

[akthoma]

I suggest checking the level of the base, not the lid. And since corner-to corner deflection/twisting could foul the seal, check all four sides and the diagonals.

OK, perhaps this is the issue then. The base isn't level front to back as shown. Does it look like I would have to adjust the screw (not sure what else to call it) in the green that I highlighted to get the stand to be level?

What's strange is that we haven't moved or touched the machine since we moved the press here 5 years ago, so I'm wondering why it would have become an issue now.