Edgebander Guillotine Retraction Issues

A detailed troubleshooting report about solving problems with the guillotine device on a Holz-Her edgebander, with good info on sources for parts and support. June 22, 2012

Question
I've got a 1990 model 1436 edgebander. Today the guillotine started acting up. It will cut the banding but won't retract. If I shut the machine down and the air pressure bleeds off, it will retract but the same thing happens next time. I think the pneumatic solenoid valve that controls it is shot. I took it apart and found some pieces of a rubber seal. I checked everything else I could think of, but the bad seal must be in that valve.

If anyone has had this issue and could confirm my suspicion, I would appreciate it. Are there any sources for parts other than Holz-her? I will shoot them an email tomorrow with a part number for a price, but know from experience that it won't be cheap.

Forum Responses
(Business and Management Forum)
From contributor B:
I had the same problem twice this year. Once it was the pneumatic cylinder... The piston/seal/plug came off the rod. The other time, the end cap on the solenoid was loose... wouldn't let the solenoid work properly. In looking for the problem I took apart the valve also - don't remember seeing any seals in it though. Holz-her does a good job of keeping lots of parts in stock for immediate shipment. You just pay a lot for them. Try Lakeside Industrial Parts. They can be quite reasonable. If it's the solenoid, you should be able to read the manufacturer and google for a seller in your area (e.g. Bosch supplier). If it's the pneumatic cylinder, look for a distributer of Parker pneumatic in your area. They'll have to make it to size but it probably won't cost a lot.



From contributor C:
Another vote for lakesideindustrial.com. Great company. Excellent tech. I had issues with my Holz-Her guillotine earlier this year. The tech talked me through it via email and phone. I ordered the parts, replaced it myself, and it works fine now. I would definitely make a phone call to them. Their number is on their website.


From contributor R:
Mine acts up from time to time. Make sure the photo eye is clean and the reflector isn't obscured. On mine, I don't count on the reflector that is attached to a lever, but rather put the reflective tape (think I got it from Lakeside) directly over the hole in the edgbanding guide. It works better that way. If the guillotine thinks banding is still there, it doesn't retract.



From contributor J:
A number of possible issues. I would suggest calling Lee Johnson, both for the help and the aftermarket parts you want. JTS handles both, and only works with Holz-Her banders. Probably one of the best in the business.


From contributor C:
For those who do not know, Lee Johnson, JTS, and lakesideindustrial.com are related. One is the service company. The other is the parts company. Great team.


From contributor Y:
I had the same problem this year. The guillotine would activate, but not always cut through the banding and then wouldnít retract. Small pieces of plastic were clogging up the fast-exhaust valve that controls the guillotine. I replaced that without success. I took the cylinder apart and found that the urethane bumper had disintegrated. Holz-Her does not list that bumper as a separate part. While Iím sure itís available somewhere, I went to the auto parts store and bought a urethane grommet that was about the same size and shaved it to fit. It has worked like a champ since.


From contributor A:
Lee has that bumper. I had to replace mine as well. He also has the special grease for the guillotine cylinder.


From contributor O:
Thanks for all the responses. I think the problem is what contributor Y mentioned. I took the pneumatic valve apart and found a crumbly reddish material in it. I assumed that a gasket in the valve had crumbled but after reading the responses I took the guillotine cylinder apart and found much more in there and also in the fast-exhaust valve. Gonna start my search for the bumper today.

As a side note, I noticed that for the past couple of weeks the guillotine was making a funny noise when it was in use. Now I am pretty sure it was the release valve gradually getting clogged.

I did look at Lakeside, which seems like a great source. I also found a place called Automation Direct... Seems like you could completely rebuild the pneumatics on a bander through them, but you would have to know your stuff as they don't reference parts for specific machines.



From contributor U:
Had that problem once, too. If the valve is Univer AF2501, then you can get a seal kit for it from granzow.com.