Bernina 1120 Needle Bar Repair

[@derekgilbert112]

Thanks from New Zealand for the very detailed info. Preparing in 2 weeks to dismantle and lubricate my gifted bernina 1120 which has no power on connection to 230v supply. Once i get underway i shall msg if there are any questions and if course provide some fees by arrangement. Kind Regards Derek

[@starlight55971]

My wife's 1090 has the same needle bar problem. I've got it apart and am working on the cleanup portion right now so perusing this was helpful to see how it goes back together. Unfortunately I missed the part where the ball could be flipped up to remove it; we ended up disconnecting from the stepper motor. So I guess I'll see if I can get that re-mounted in the same position as it looks like it may have some adjustment on the motor mount. Whoopsie! Of course one of the clips launched itself into the internals so I'll need to magnet that out of there wherever it ended up. Thanks for the video walkthrough, I'm sure it'll be useful when it goes back together.

[@ramanabulusu4175]

Hi , thanks for explaining such a difficult task. Now ., is there a huge difference between 1120 & 1130 models? My 1130 ( new to me ) seems to have this problem because of which the Hand Wheel is completely “ frozen “ and I am not able to move it at all. Could you please throw some London light & give me tips? Also., if this mechanism is out of function., is the hand wheel “ frozen “ ? I would really appreciate your feedback ASAP. Thanks.

[@sewingmachinetipsandtricks9079]

I will need more information. I believe the main differences between the two are the electronics and the stitches. So for as being locked up the problems would be similar. Is your bobbin winder engaged? On some machines that will lock up the hand wheel, I can’t remember if the hand wheel locks when the bobbin winder is engaged in these 2. If that is not the problem then it could be the needle bar, in the hook area or the bushings. I can offer more help if you would like.

[@safeseller4348]

Fantastic video. My L4200 0885 110V power supply board (the one that your video shows) has a blown R10 resistor and two blown Diodes. I found replacement diodes but cannot identify the resistance value for R10 (located under lower left corner of the big transformer). Do you happen to know the resistance value of R10? Thanks Rick

[@starlight55971]

In-circuit on my 1090 machine I'm showing 1.2-1.3 ohms, with some variance due to the lead's internal resistance. That's on L1230 0691 110V so it may differ. (Or maybe it's L1230 100 110V, that's what the orange sticker says versus the black printing near the transformer. /shrug)

[@starlight55971]

Looking into it further, the resistor has 1R stamped on it so that should be 1 ohm. Again, assuming it's the same as yours. Big green resistor without color coding.

[@safeseller4348]

@@starlight55971 Thank you so much for taking the time to look into this. I installed the resistor remotely (next to the motor in the airstream of the motor's fan) so hopefully the resistor heat will not affect the diodes on the board as much. This machine gets a little hot when powered on and not running. I measured 160F near the SCR at the top of the power supply board with the covers screwed on. Needs a cooling fan maybe...