A new gremlin has reared its head with my Universal 3, I’m having trouble with the cycle start button. Sometimes when the button is pushed nothing happens, if I hold it down it seems to eventually start the cycle and the time I need to hold it down varies from a second or two to what seems like forever. I dont believe its a short in the button itself because if I switch it to manual mode there is no movement using the toggle switch. Any help would be greatly appreciated. Thanks
AJ, I thought the same thing when I saw Dan’s list. I’m setting up an excel file to make a searchable table. Please let me know what other parts you want to see added to the list.
Quick update on the cycle start issue. We started with what I considered the easier of the two fixes and swapped out the outer two limit switches on the rear of the press. Happy to say that this seems to have done the trick! Cycle start button fires off without a hitch now. Switched it to “run” and let it do its thing for a full 15 minutes with no issues.
What this experience has taught me is to start stockpiling replacement parts for the electronics. The list of part numbers that Dan provided is absolutely invaluable for a new Uni3 owner such as myself, Id highly suggest permanently adding it to this website somewhere for future reference.
Thanks again for all the help in remedying this issue!
Thanks all and my apologies for not responding sooner, I’ve been swamped in the studio. I believe we have narrowed it down to one of the relays but yes the limit switches could certainly be the culprit also. I received a new relay today and have a couple new limit switches in hand already. I’ll start with the limit switches on Monday as I’ve done one already and they’re much less intimidating than the relay but will move onto that if the switches don’t remedy the problem. Ill report back on Monday when I tackle all this. Thanks again!
Basil Head, a seasoned press mechanic in the UK writes:
These are some of my parts number notes for the Uni III. I would love it if people would comment and add to this. I have done well using these parts numbers to find new old stock spares on eBay and surplus sites.
ALLEN BRADLEY 800T T2MB21 – main forward, stop, reverse lever assembly
OHMITE VT 8X VARIAC – not the same as VT-8
OHMITE DOSX-7T 15A 115V AC
OHMITE L50J200K – make sure it is the correct length
OHMITE L25J500 500 OHMS 25 W RESISTOR – make sure it is the correct length
OHMITE 0319 RHEOSTAT
12MA7 BUTTON – main green button on press
GENERAL RADIO KNSP-6 BLACK (sourced from Leeds Radio)
GENERAL RADIO KNSP-8 BLACK (sourced from Leeds Radio)
RBM 45211-2 MOVABLE CONTACT
RBM 45200-2 STATIONARY CONTACT
MALLORY FP119A CAPACITOR
B2A BULB (run bulb on SP, Universal presses)
2811 RED DOME LENS (ALLIEDELEC.COM)
I recently had a similar problem and blamed the relay so I swapped it out with an NOS one found on eBay. The part number is OHMITE DOSX-7T 15A 115V AC. When I went to change it I found that one of the connections had popped a solder joint and the old unit was probably fine.
The main speed control rheostat/variac has more often caused me problems. I have found that by slightly changing the speed it sometimes makes contact and happily chugs back into action. Noting this, I found that a light pull on the speed control knob made the press behave happily. There must be some wear in the contacts that was causing poor conductivity. My mildly ridiculous fix for this was to take off the knob, stack a couple of washers behind it on the shaft, and re-tighten the knob while pressing outward from the inner face of the rheostat. This kept a little bit of outward pressure on it and has brought the variac back to life.
I have also recently had to replace the main ‘forward’ RBM contactor relay. The connections were all good, and the points are fresh, but the magnetic paddle assembly on the back had popped free and was weirdly half-working. I was lucky to have a spare in my parts stash.
Have you changed the resistors yet? Most of the parts in there can still be bought if you cross reference the part numbers.
I don’t hear any relay “chatter” in the background of your video, but that would be one thing to check, maybe a relay is not making good contact right away. You might open the back door and see if you see anything interesting going on there as the button is pushed.
I did check on my Universal III, and tried using the cycle mode with varying time delays, and found that the setting of the time delay rheostat did have some effect on the timing of the start of the cycle. I had thought the delay only came into play when using the press in “run” mode, but there was a substantial delay before the forward relay engaged after the “cycle” button was pushed when the delay rheostat was set to maximum, and less of a delay when the rheostat was set to minimum delay. If you look at the schematic diagram in the manual, you can see that the circuit does go through the time delay relay, and assumes it to be in closed position.
If, however, the delay varies without moving the rheostat position, there may be some problems with the delay rheostat (might need cleaning) or the delay circuitry. Make certain all the terminal screws are tight on the “time delay board”.
Try various settings and see if there is a change in the response time of after pushing the “cycle” button.
Please report back your findings so we can add to our troubleshooting files.