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karossii
01-31-2015, 07:04 AM
So after 5 rotary lithophanes, 3 of which are usable, my jig came apart. The large gear came off as I was removing the last PVC pipe from the jig. The belt stayed put, for the most part, and a single washer fell to the floor. I did not notice anything else come off or anything. Anyone else had anything similar happen? Is there any sort of fix for this, or do I have to get it replaced (hopefully they will cover it under a warranty of some sort)?

blhutchens
01-31-2015, 07:19 AM
You should be able to put it back together. there should have been a nut on the keypad side that holds every thing together.
I have had some of the same issues as you. I countersunk the screw holes in the large gear a little deeper and put a washer in between it an the plate.
I also put a jamb nut on the end of the stud to keep it from working loose again.
I always hold the belt when unscrewing the project from the center stud to prevent the large gear from coming loose.
sometimes I have to hold the jamb nut with a pair of pliers to keep everything tight while unscrewing the project.

bergerud
01-31-2015, 09:18 AM
I am not sure what came apart. Can you post a picture?

I got an early model which I thought needed some modifications. The gear was easily pushed too close to the aluminum plate when tightening the jig on the dowel. It was only the press fit of the head bearings which positioned the gear. I added a spacer between the two head bearings and a washer behind the gear. I also added two washers under the two screws on the back to hold the bearings from pushing out.

karossii
02-02-2015, 06:20 PM
Okay, sorry for the delay. It was a long sleepless weekend trying to set up and run a craft show booth, along with the myriad of other things on my plate right now.

So the screw never had any nut(s) on it, on either side of the jig. I guess you could say it came a castrato. That might be a contributing factor, but I don't think so since it was the bearing that that screw is threaded through that has come out. The screw did come out once or twice, but I simply screwed it back in place when it did so.

There are obvious scratches on both the gear and the jig, I think from the first set of screws I used (the ones shown in the demo video with the larger, black heads). I am 100% certain that the second set of screws I got were screwed in below the level of the gear, within the countersink - their heads were half the size of the black screws, and sat well within that depression.

I have sent these pictures to CW's tech support as well... hopefully I will hear back positively soon.

I tried manually pushing the gear back into place, and it is beyond me - not without the use of a vise, hammer or similar method to focus and/or multiply the force I can exert - and I do not want to do that for fear of damaging the jig.

bergerud
02-02-2015, 08:00 PM
You should be able to push the axle back into the bearings. Mine slides in and out fairly easily. The bearing has pushed in a little and that is why the gear wheel and screws scraped. I put a washer between the two bearings and then put those small washers on the screws on the back to stop the rear bearing from moving. If you can push the shaft back in, you would need another washer to keep the gear wheel from rubbing again. I think all the parts (except the shaft in the gear wheel) can be persuaded in and out with fairly gentle forces.

If I were you, I would just add another washer like the one behind the gear (so you have two of them) and tap it back together.

(Sorry, I deleted my first post because I posted before I read your whole post!)

flyingemt
02-11-2015, 05:19 PM
Dan, is this a design flaw in the engineering? I seem to have noticed my problem before it started, noticing the metal to metal between the main plate and gear. In a nutshell a couple washers will resolve this?

Mike

74400

bergerud
02-11-2015, 05:30 PM
The design relies on the bearings being a press fit in the aluminum. When you tighten up the jig on a dowel, the bearing can be pushed in. Another washer behind the gear should solve the problem as long as the back bearing does not also move. (I assume now that the small gap between the bearings has closed and you will now be pushing on both bearings.) The small washers like in my picture can fix that.