Can't figure out automatic buttonhole use on MC4000

Are you asking if you can do a buttonhole without the special buttonhole feature? If so--of course you can. Sewists do it all the time on machines without the buttonhole feature or special feet. Be sure to practice on some scrap fabric first.

How to sew buttonhole with an old machine

Until Wednesday Calls How To Manual Machine Buttonholes

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The machine's timing may need adjusting. Has it been serviced recently? If the book does not say how to make a buttonhole, perhaps this feature is not available.

I would suggest taking the machine back to where you bought it & letting them show you how to make a buttonhole or getting another
machine

This is not the problem of the thickness, but of the softness. Fleece will pull unevenly, causing the dogs to simply tug at layers of it in place, instead of moving it. You will have to (GENTLY) assist the dogs in moving your fabric, if your fabric is this soft.

The cause of this is 90% on the fault of the fabric, and 10% on the way the buttonholer foot works. The foot is built to hold the fabric fast in place, with sliding action only permitted by the buttonhole guide. However, this is assuming the dogs can get enough purchase to move the fabric around. Simply put, again, you will have to help the dogs along with this one(you will be able to clearly feel the difference and which way the dogs "Should" be moving at the time when you attempt to, as once it catches in one direction, it is likely to keep going in that direction until the dogs stop.)

I just figured out how to use the buttonhole feature today. Make sure where you insert the button is towards the back of the machine. Pull down the button hole lever and make sure it's between to two plastic notches. The buttonhole lever will actually be pressed against notch B as described in the instructions. Insert your material and let the bottonhole foot down. You will to play with the stitch width and length to get the right size opening. I hope this helps!

I'd forgotten to pull the little lever down that abuts onto the buttonhole foot! Simple!

Lots of tutorials and videos online:

One Step Buttonholing

How to Use an Automatic Buttonhole Foot

SINGER 1 Step Mechanical Buttonhole Presser Foot Tutorial

How to Sew Buttonholes for Beginners by Babs Rudlin at Fiery Phoenix

If everything appears to be working correctly for the first side and stops and bunches up when it should reverse - Make sure you have pulled down the stopper arm (this is not clear in the manual) when the button hole foot contacts the stopper arm gently push the foot against the stopper arm and the direction will reverse and finish the button hole. **Stopper arm pulls down from above - Check the pictures in you manual carefully.**

There are TWO buttons on the machine that have the little u-turn on them. Look for the other one. That is the one that makes the second half of the buttonhole. Look in the owner's manual, it may tell you where it is on your machine. I spent a long time swearing at my machine before I figured out that the reverse is not the only button with the u-turn arrow. The manual is not clear on this. Why they use the same symbol twice is beyond me. Mine is on the front of the machine, down by the needle. Hope this helps.

Perhaps one of these would be helpful:

SINGER 1 Step Mechanical Buttonhole Presser Foot Tutorial

looks like your machine uses the 1-step buttonholer

practice on some scrap fabric first!
One Step Buttonholing

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0ahUKEwieqOiL1arUAhUo7YMKHThcANQQFggsMAE&url=http%3A%2F%2Fwww.singerco.com%2Fuploads%2Fdownload%2Fef975f80499782c000847791f6ebfa75cfe72aa9.pdf&usg=AFQjCNHPO3ZhMUMYZDvyr0hPFbEf8BFR9w&cad=rja

SINGER 1 Step Computerized Plastic Buttonhole Presser Foot Tutorial

How to Use an Automatic Buttonhole Foot

How to use an Automatic Button Hole Foot

How to Sew Buttonholes for Beginners by Babs Rudlin at Fiery Phoenix

My Singer 2950 buttonhol er stitches only one side of the buttonhole It...

good luck!