Casn I use a double needle on this model? - Necchi 6015 Mechanical Sewing Machine

Yes, it will work.

Don't know the model of your machine but this manual, or one specifically for your machine, may be helpful:

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0ahUKEwio3tC-1p7PAhXm5oMKHed8DIMQFggeMAA&url=http%3A%2F%2Fjanome.com%2Fsiteassets%2Fsupport%2Fmanuals%2Fsergers%2Finst-book-634d.pdf&usg=AFQjCNFFa0YXjvhgmGspP4BP7E6p_z59bA&cad=rja

FWIW, overlockers do not take double needles. There are usually at least two needles each installed separately. If you try using a double needle, you will most likely break them and possibly damage you machine.



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try these links for a manual, and the manual should have the information

New Home 535 Manual Instruction


Janome New Home 535 Instruction Manual UK Sewing Machines


New Home 535 Instruction Manual


Newhome Janome model 535 Sewing machine

No make/model was provided, so there is no way we can assist with your question. The Owner's Manual should have instructions whether a twin needle can be used. If you don't have one, search the internet for:

Make + Model + the word "Manual"

or contact the manufacturer directly.

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Most all machines will take a double needle

The length of the needle might be too short. Compare the length to your single needles.

for a double needle, first thread the first needle, then put the second spool up & thread in the same places as the first, making sure every guide is used, then thread the needle.

that's how I do when I used my double needle to sew

firstly are you using a regular twin needle on a knit fabric? this could cause skipped stitches.
is the twin needle quite old and possibly blunt?

Is the Hobbymatic a model that requires a slanted twin needle, there are two types of twin needles as the computerised machines need the offset style. You can distinguish between them by the plastic block on the needle shaft where the twin needle points are set, either red or a deep brown colour.

If none of the above apply, then it is possible that the timing sequence is slightly off so that one of the needle's thread is not getting caught during the stitching.

Timing is an adjustment that I leave to the technician to address. But if you want to have a go yourself there may be some videos on you-tube for your model and how to make this adjustment to it.

double check the upper and lower tensions they often need to be changed to suit types of fabric and threads

if the machine regular needle threads front to back NOT side to side, you can use a double needle. simply pass both threads thru all the same slots (thread one at a time so they don't get twisted up) then just before the needles, leave one out of the thread guide just above the needle. you may have to loosen the top tension SLIGHTLY, like a half number. and do NOT use a zig zag stitch without first hand cranking it thru the cycle to be sure the needles clear, or you'll make a 5.00 mistake (the cost of the double needles!)