Pressurized Glue Pot Basics

      A quick intro to pressure pot glue systems. August 31, 2009

Question
I have some more questions about pressurized glue pots. I have an opportunity to buy a used glue pot from a fellow who closed his shop down. He bought it from the people who sold him his HESS clamp. I have it at my shop right now but have not yet put any glue in it. I did charge it with air and this is what we have observed:

There is a warning label saying not to exceed 5 BAR. The pressure gauge reads both pounds of pressure and BAR. I am not sure what a BAR but the equivalency seemed to be about 60 lbs so that is what we ran it to.

There is an on-off switch inline with the air feed fitting but no otherwise apparent way of knowing when to stop feeding air. Initially we thought it might be missing a regulator but the HESS website does not show one. The pot from Colonial saw also does not seem to include a regulator.

My question is: how do you load the air, or rather, can you load too much air? There is a pressure relief valve. Do you juice it until this kicks off?

Also: after we put 60lbs of air into the system it seems to slowly leak pressure out. It is a slow leak but a leak nonetheless. I don't have any experience to compare this with. Should it be leaking air slowly? As I understand from the HESS website, you are supposed to be able to charge it with air then unplug it for walking around. Is this how everybody else's works?

The fellow who is selling it never actually ran it so he has no answers. If anybody who is using a similar pot could tell me how theirs works I would sure appreciate it. Mostly I want to learn how to know when I have enough air and how long a charge of air should last before needing to be re-charged.


Click here for higher quality, full size image

Forum Responses
(Cabinetmaking Forum)
From contributor O:
I have the Hess system with LogDos pot and Pizzi fittings. My pot is a little different, the relief valve and air inlet are separate. From your picture it looks like you have a black shutoff on the air inlet. We just put a quick connect on this. Connect the air line to it, open the valve till the gauge hits 5 BAR and shut it off. You donít need any more gauges. No stress about the pressure, they will pump glue even at 2 bar. We usually never recharge ours till the glue pot is refilled.

If air is leaking out check the gasket and rim of the pot to make sure everything is clean. You have to tighten these a little more than you would think. Our pot is larger similar to the Colonial pot in your picture. We have to tighten the wing screws in sequence a few times. Yours is a single pressure point. Check the gasket.



From the original questioner:
The pressure relief valve on ours is separate from the air inlet. The air inlet has an inline cock-valve. What I think I read in your response was that you hook up the air line and open the valve until the gauge hits 5 bar. What happens if you zone out and go past 5 bar? Presumably the pressure relief valve kicks off? Would this relief valve just reset itself when pressure drops to acceptable levels? Also, (sorry for being obtuse), you said that you pressurize the tank and then don't have re-pressurize until the glue in the plastic pot is empty? When I get to the shop next I will check the gasket and tighten the top screw.
How feasible do you think it would it be to take some UHMW plastic and make a cope pattern for gluing ogee doors?


From contributor O:
Believe me, this is the simplest tool you will ever own. You asked, "the air inlet has an inline cock-valve. What I think I read in your response was that you hook up the air line and open the valve until the gauge hits 5 bar." The answer is yes.

"What happens if you zone out and go past 5 bar? Presumably the pressure relief valve kicks off? Would this relief valve just reset itself when pressure drops to acceptable levels?" Weíve over filled ours, just bleed it off. The relief valve never went but if it does no big deal.

Also, (sorry for being obtuse), you said that you pressurize the tank and then don't have re-pressurize until the glue in the plastic pot is empty? Yes, if itís leaking time to check the lid and gasket.

"How feasible do you think it would it be to take some UHMW plastic and make a cope pattern for gluing ogee doors?" I think that is feasible but the small Pizzi brush might work as well.


Click here for higher quality, full size image



From contributor R:
For what it is worth 1 bar is atmospheric pressure - 14.7psi.


From the original questioner:
To contributor O: since this is the simplest tool I will ever own, I only have one (actually two) more questions: if the pot stays under pressure until you run out of glue, do you have to wait until it completely runs out before filling the glue chamber again? If you wanted to top off the glue before it ran out, how do you bleed off the pressure without ending up with glue everywhere? Question two: where do you get the Pizzi brushes?


From contributor O:
To the original questioner: just use it for a week and quit stressing about all this irrelevant stuff. Seriously - you can open the black valve at any time with glue in the pot to release the pressure. Nothing will squirt out. Gluing door staves and skins with the roller attachment we go through a lot of glue and always top the tank off before starting. No problem.

Building cabinets you wonít go through much glue. I would be surprised if you fill the tank more than once every week or two in a small shop. If your careful to keep the inside lid and gasket clean at glue changes you should not have any pressure leak problems. We have a glue tipper on the cart that works good for filling the tank. I try to totally clean the pot and flush the hoses every couple years. You should have a threaded attachment to use a hose to clean the glue nozzles and attachments. The roller is the only one we have that requires care after use. The nozzle and dowel gluer are fine sitting in the water tank for days or weeks. Titebond 1 and 2 work easy in this. Titebond 3 gets lumps that sometimes clog the screen filter in the pot.

For house door assembly we use the dowel nozzle and a hand glue brush. I still like to brush a little glue on end grain. We just started using mortise joints on window frames. Pizzi makes an attachment for this but think I will try the brush first. For cabinet doors I think the small brush might be the ticket. You will be surprised how well the standard nozzle works for most things.



From the original questioner:
You have just reduced my learning curve from one week to one hour. I think I came out best on this transaction.


From contributor L:
We've got the Lamello version for doweling. It works great, keeps pressure for a long time. Titebond 1, push the trigger and it puts a measured amount in the hole. Put the applicator in the water jug and leave it until next time, no plugs.



Would you like to add information to this article?
Interested in writing or submitting an article?
Have a question about this article?


Have you reviewed the related Knowledge Base areas below?
  • KnowledgeBase: Knowledge Base

  • KnowledgeBase: Adhesives, Gluing and Laminating

  • KnowledgeBase: Adhesives, Gluing and Laminating: Gluing and Clamping Equipment


    Would you like to add information to this article? ... Click Here

    If you have a question regarding a Knowledge Base article, your best chance at uncovering an answer is to search the entire Knowledge Base for related articles or to post your question at the appropriate WOODWEB Forum. Before posting your message, be sure to
    review our Forum Guidelines.

    Questions entered in the Knowledge Base Article comment form will not generate responses! A list of WOODWEB Forums can be found at WOODWEB's Site Map.

    When you post your question at the Forum, be sure to include references to the Knowledge Base article that inspired your question. The more information you provide with your question, the better your chances are of receiving responses.

    Return to beginning of article.



    Refer a Friend || Read This Important Information || Site Map || Privacy Policy || Site User Agreement

    Letters, questions or comments? E-Mail us and let us know what you think. Be sure to review our Frequently Asked Questions page.

    Contact us to discuss advertising or to report problems with this site.

    To report a problem, send an e-mail to our Webmaster

    Copyright © 1996-2016 - WOODWEB ® Inc.
    All rights reserved. No part of this publication may be reproduced in any manner without permission of the Editor.
    Review WOODWEB's Copyright Policy.

    The editors, writers, and staff at WOODWEB try to promote safe practices. What is safe for one woodworker under certain conditions may not be safe for others in different circumstances. Readers should undertake the use of materials and methods discussed at WOODWEB after considerate evaluation, and at their own risk.

    WOODWEB, Inc.
    335 Bedell Road
    Montrose, PA 18801

    Contact WOODWEB











  • WOODWEB - the leading resource for professional woodworkers


      Home » Knowledge Base » Knowledge Base Article