Manual necchi 6018?

Only from the maker by the looks of it.

https://necchi-usa.com/search?q=walking+foot

Not available from the normal outlets. One on Amazon but not for your machine.

https://www.google.com/search?q=necchi+6018+walking+foot

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Your owner's manual should tell you what type needles your machine uses. According to this site, 130/705 needles will work with your machine, are also very common, and are available in several brands: Schmetz, Janome, Organ, etc.

http://www.sewingpartsonline.com/necchi-6018-sewing-machine-parts.aspx

In addition, you will need to determine the needle sizes (60/8 through 120/19) as well as the needle point (universal, ball-point, sharp/microtex, top stitch, embroidery, leather...) so the needle is compatible with the thread and fabric you are stitching.

SCHMETZ Household Needle Chart

Be sure to change the needles frequently. A needle should be replaced about every 8 hours of sewing time. Sewists tend to skimp in this regard (although needles are the least expensive fix!), but the needle is the most frequent cause of sewing machine issues. So, if your machine begins to misbehave, the first thing to try is a brand new needle.

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try these suggestions
Needle breaks
1.the needle is damaged
2.the needle is not correctly inserted
3.wrong size needle for the fabric
4.the wrong foot is attached
5.the needle clamp screw is loose
6. Top tension is too tight
7. Machine could be out of time

Try [email protected]

there is a door on the left it's called a lamp cover door or a face plate- on my mechanical necchi there are hinges behind the door at the back,,gently pull open the door & the bulb will be accessible

on my other necchi there is a cap in the middle of the door with a hidden screw, gently pry the cap out & take out the screw & there is the bulb,,just reverse the process to put the door back on

can you give more information about the foot tension problem

try www.sewingonline.co.uk/instructions or www.sewusa.com

Adjust the stitch length so that it isn't too tight.

Make sure that you are using the buttonhole foot. It has a groove in the sole to allow the foot to pass over the bulk of thread.

If you still have problems, the reverse cycle balance (stretch balance) may need adjusting by a technician.

this is one place

http://www.sewingmachineparts.net/pricelist.html

just google the part you need for more stores

Robert

If the thread is not clearing the hook te chances are the machine will need retiming, have you checked for any sharp edges or burrs ont the hook that might be holding it back, if the machine is sewing perfectly once you getit going and is not missing stitches the timing will be okay.