Windmill shearing collar

jonsel
on 30 Jun 12 (13:56)

I was attempting to run a job today with a fair amount of solid coverage. In doing so, I had cranked the impression up to around 3. The press would occasionally lock up on me (once every 50 or so sheets), but I could easily release the impression lever and it would be fine. On the last go, it locked up and I couldn’t release it. After attempting to release the pressure on the knob by turning it back to 1 or so, it still wouldn’t release. Rightly or wrongly, I thought, maybe I need to check the shearing collar. I got 5 of the 6 bolts off but was having trouble with the 6th. I went back to the impression lever and finally was able to turn the knob back to lower the pressure and it finally released. I went to print a few more sheets and noticed the impression was all screwy.

So, my question: did I break the shearing collar? Should I have tightened the bolts back before running again and that would have fixed the impression issue? I did finally get the shearing collar out. Photo attached. It looks ok to me. I’m assuming the 2nd piece is the spacing washer. Thoughts?

thanks,
j

shearcollar.JPG

leftarmletterpress
on 1 Jul 12 (12:15)

shearing collar looks fine to me.

jonsel
on 1 Jul 12 (18:28)

Ok, thanks. I wasn’t expecting anything other than the collar when I opened the back and was under the impression (ha!) the collar would be in two if I had broken it. Hence, seeing two pieces, wasn’t entirely sure.

Peter Luckhurst
on 2 Jul 12 (14:39)

Updated 2 Jul 12 (14:45)

Your collar can be blown and still intact , claen it with a rag and inspect with a high magnification ,or dunk it in water for a couple of days retrieve it and clean with wire wool and if blown you will see miniscule cracks radiating out from the centre , they expand when blown thats what makes them difficult to remove if you dont know the knack .
As an aside ti that you relieve the jammed machine by lifting the safety pawl and reversing the platen one inch or so ,not more , if you dont know where that is you must read the hints book , it is extremely important that you know how to do this operation and are able to relay that instruction to another person or teach your fellow workers how this pawl is lifted. Should you get trapped in the press this is the fastest way to back the press off , everyone around you should know how to do it .

jonsel
on 3 Jul 12 (15:18)

Thanks, Peter. I can see a very small crack on one side. I’m looking for a replacement, but I may try to see if I can use it in the meantime.

I’ll look into that safety pawl/reversing the platen thing, although I’m often the only one here, so I’m probably better off having my cell phone handy!

Peter Luckhurst
on 3 Jul 12 (15:45)

You will be able to source one from whittenberg , dont bother with trying chinese versions they are not reliable .
The last ones i got were about £50 U.K. been a while since i burst one but a lot of the stuff seems to be quite affordable in the scheme of things !!