Bernina 730 Can't open top cover !

There are actually two Bernina 730 machines (confusing, huh?). One is the 730 Record from around 1960. The other is the more modern 730 computerized model made in the 21st century.

The 730 Record has a hidden pressure adjustment. Lift the top cover and locate the screwhead on the very left side (left of the takeup lever knuckles). This screw loosens or tightens the spring that applies pressure on the presser foot.
The manual can be downloaded here, although it does not show the pressure adjustment:
BERNINA Sewing Systems

On the computerized 730, the pressure adjustment is on the screen (pg 37 of the manual):

BERNINA Sewing Systems

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try these links

BERNINA artista 730 Support BERNINA


Bernina 730 Record Parts


Bernina 730 Sewing Machine Cleaning oiling and Maintenance

The Bernina 730 Record is a great little machine. If the selector levers are sticky/stuck or the handwheel is stiff or does not turn, about 98% of the time the machine needs oil.

Mechanical machines need to be cleaned and oiled regularly just like your car. If the machine sets in storage for a while or is used often but not oiled or cleaned regularly, the oil that exists in the machine will eventually thicken and acts like glue. (Sometimes you can see a dirty-looking dark gold or brownish goop which is usually old oil.) Then your machine is frozen.

First, open the top and bottom of the machine and sweep out any dust, dirt, lint, or stray threads.

Now, oil your machine (there's a diagram below). There are quite a few oil holes (both in the top and bottom of a Bernina mechanical) that require periodic oiling (see your machine Manual). If a metal part is frozen, buy a bottle of liquid Tri-Flow Synthentic Oil (from the hardware store) and put one or two drops in all the spots shown in the manual. (DO NOT oil rubber parts, the two white plastic gears, the belts, or the metal CAMs!!! NEVER use 3-in-1 oil, cooking oil, WD-40, or oil from your grandma's sewing box. And do not put more than one or two drops of oil at a time as over-oiling will also damage your machine.) It also helps to slowly hand rotate the handwheel and, while watching things that move, apply 1-2 drops of oil every place that metal rubs against metal. Do this also with the selectors and dials.

Then, using your hand-held hair dryer, direct hot air into the internal part of the machine (top and bottom). The metal may become hot to the touch. Then try to gently move the handwheel and the selector levers. Repeat. Let it set overnight. Then test again the next day, and repeat the process if needed.

To maintain your machine, a good recommendation is to oil every time the bobbin thread is changed, every 8 hours of constant sewing, or every six months if the machine is not in use. Use a good quality oil, ie Bernina oil for "mechanical" machines. When oiling, also be sure to brush out the dust and lint (especially around the feed dogs and bobbin works).

If the oil in your tube looks dark colored, throw it out and get some new. I've run across some old sewing machine oil in the can that looked like dark honey and stunk to high heaven. Get rid of it!

Treat your machine well and it will serve you well for many years.


This is an oiling diagram of an 830 Record which is very similar to the 730.



This is an oiling diagram for the 930 Record. Also fairly similar.
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Machine needs a good cleaning and oiling. Might try directing hot air from a handheld hair dryer into internal mechanism concentrating on the selector knob mechanisms.

doesn't sound like he tried real hard, my suggestion is to find a sewing machine shop that will take the machine apart & find out why the selector doesn't move, it's possibly a worn or loose or broken part, & the repair man is suppose to open the machine & find out what's wrong.

The 730 rotary hook is a bit sensitive to adjustment and cleaning. Make sure that the hook is clean and if you haven't oiled it for a while, give it a drop of oil (do you know where to put it ... many dont !) Check your needle is OK and, again, if used for a while, just put a new one in anyway. Load-up with different colours of the same type of thread top and bottom and sew-off a sequence of zig-zag, starting with the default and increasing the width and reducing the length until you get to a maximum width satin-stitch (dont increase the bobbin or top tension as you do it). Once you've done that, let me know what it looks like. The colours should be equal top and bottom, but maybe just a bit of top coming through to the underside on max width satin stitch. You'd also be advised to sew-off using pattern number 437 and the figure '9' - this will check the balance of the machine. If the '9' is not perfect, or the top section of the pattern 437 is not dead-central on the top of the triangular part of the pattern, the balance may need adjustment. Let me know how you get on.

HI
All that is wrong is that the plunger that holds the lid down is likely siezed with old oil. If you are careful you can slowly insert 2 flat sided screw drivers under the front part of the lid on either side of the right and left side of the lid and slowly move them toward the middle , thus the plunger will likely give way and the lid will pop open.
If this does not work contact me at [email protected]

Wayne Buss

I looked at this manual - http://www.berninausa.com/webautor-data/486/BERNINA_730_731_732_manual.pdf and cannot determine how to do this without the aid of a flat edge screw driver.

I know this is a long-overdue response, but maybe it will help someone else. I had the same problem, and it turned out that the cause was that my bobbins had oxidized. Rubbing them with a bit of steel wool or fine-grain sandpaper did the trick, and I was up and running again.