Windmill Gear Tooth Missing - Needed?
Let me start by saying that I am a newbie at this Heidelberg thing. Today I was teaching myself paper feeding and every so often the feed table would drop with a bit of a ‘clunk’. It didn’t seem to interrupt the suckers picking up the paper, grippers grabbing and delivering it, etc. After I stopped the press I looked underneath at the series of gears that raise the feed table and one of the gear teeth is broken. I looked in my parts manual and it is part # T 1104. I guess my question is, do I need to replace this part? Or can I get away without replacing it?
I’m attaching a photo below. Thanks for any insight you can provide.
Carrie
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If you are going into mass-production, producing 1000s of prints from the same forme, then I should say replace it, otherwise you maybe able to continue as is, but with a certain amount of inconvenience.
If I remember correctly, and its some 15 years since I handled a windmill, the feed table lift includes a ratchet mechanism to prevent over running; if you can use this so that the broken tooth is not in engagement at the height your feed table needs to be, then maybe you will be lucky.
Thanks, Bern for your comments. Do you think it would be possible to weld another tooth in there (since it’s not a precision gear to begin with) or swap this gear for the one directly behind it (Both # T 1104)?
Had I known that it was broken, I wouldn’t have had the extra rollers recast and would have instead spent the money on this! These presses do get expensive…
I don’t think swapping the gears around will solve the problem; it will still slip when it synchronises with the missing tooth.
It should be possible for a good engineering shop to weld a new tooth in, but whether it will last, or be cost effective compared to a new one is debatable
A machinist would tell you that the whole gear should probably be replaced. If one tooth is chipped, chances are a lot of strain has been put on the rest of the gear.
A machinist would also charge you a few hundred for a new gear…Though an involute spur gear isn’t a difficult thing to have made, and given its use, you wouldn’t have to worry about the cost of hardening and whatnot.
A weld might be possible, but it will only make any existing flaws in the gear that much worse. If you are using the press for production, Bern is right, replace it. Heidelberg might have parts, and machine shops are extremely eager for work right now, so they will give competitive quotes.
Thank you both for your advice. I really appreciate it. I did manage to find someone who had the part, but am not ruling out machining a new one or maybe finding one that is a little less money.
hi, I have had missing teeth on gears restored by a 1st class welder. One case with the flywheel in place on a old Ford pickup he rebuilt 3 teeth with hard surface rod and ground them to shape. It got me down the road for a year. It would last a life time for your application. Dick
Thanks, Dick. I’ll definitely explore this option as well.