Part of Metal Type’s Printing Advice section, here Phil gives advice on removing a press flywheel.<\/p>\n
Removing a flywheel, employing a wheel or gear puller is sometimes a necessity.<\/p>\n
My comments are: \u00a0be real careful here, this can be super tricky. \u00a0Do not even attempt this unless you are really mechanically inclined and experienced.<\/p>\n
I would\u00a0advise\u00a0trying most any other method of moving a press other than attempting to\u00a0remove a flywheel.<\/p>\n
Some manufacturers fitted a\u00a0flywheel so tightly that it had to be heated to get it on the shaft and then used a square pin\u00a0in a channel called a keyway, to ensure that the wheel did not shake or\u00a0vibrate off.<\/p>\n
And\u00a0getting\u00a0such a wheel off sometimes\u00a0requires\u00a0dry ice wrapped around the shaft, for 12 hours and then the hub of the wheel has to be heated with \u00a0two or more blow\u00a0torches, to facilitate the removal.<\/p>\n
And be really \u00a0careful to heat only the hub and heat it as fast as you can so as not to leach away the cold from the now hopefully shrunken shaft. This is the reason for using more than one blow\u00a0torch for heating the hub.<\/p>\n
And the reason for the\u00a0dry ice being on the shaft for 12 hours is to be sure that the shaft is as cold as the dry ice and that\u00a0there is\u00a0enough \u00a0“cold sink,\u2019\u2019 in the shaft so as to last as long as possible, and that there not be too much cold loss in the shaft\u00a0till the hub is heated\u00a0enough for the wheel to be removed.<\/p>\n
Also the square pin in the keyway, can be a bear-cat to remove. I\u00a0have had to\u00a0drill out\u00a0several of\u00a0these pins. And they all seem to be\u00a0machined from the hardest steel that was ever made. This is\u00a0really hard to do and can take hours and many more than one drill bit.<\/p>\n
I always use carbide drill bits for\u00a0this sort of job and once had to switch to a diamond drill bit. These speciality bits are all so expensive.<\/p>\n
I personally would prefer to remove part of a wall and remove the press, rather\u00a0than try to remove the flywheel.<\/p>\n
I have seen this kind of job proceed\u00a0without any trouble at all, Just remove the square pin, if there\u00a0even is\u00a0one, and then manually pull the flywheel off. Nothing to \u00a0it at all.\u00a0Just as easy as you please.<\/p>\n
On the other hand, I have seen this job take two days and one\u00a0journeyman\u00a0machinist \u00a0and two highly\u00a0qualified helpers. \u00a0And \u00a0over ten high quality drill bits to\u00a0remove the\u00a0square pin.<\/p>\n
Lastly; \u00a0good\u00a0luck to you. The wheel may come off easy peasy. Or you may find otherwise. Again, good luck and please do let us know how it went.<\/p>\n","protected":false},"excerpt":{"rendered":"