I recently bought a Singer 1507, I sewed few seams and then the thread tangled underneath, the needle stuck and it took some time to free it. I was unable to fix the problem even going through all p

This is common... and typically caused by operator error. First take the thread spool completely off the machine... and replace it then rethread making sure that it's done properly and with the pressure foot in the UP position

Second... make sure that when you are starting a seam.... grasp the thread ends until you are at least 2 inches into the seam.

Third if you are successful you are done.... if you still have loops and tangles below, adjust your top thread tension (little bits at a time) sew a little, then adjust again a little.

4th... it's unlikely... but it does happen. Every once in a while.. especially after a needle break... your bobbin can get a nick or burr... as can the hook. Inspect carefully with a strong magnifying glass. If you find a burr try some emery board or fine sand paper. While you are at it check your needle.. it may need replacing too.

Good luck!

The bobbin might have a bunch of thread off it inside the compartment here the bobbin is. Also, make sure it's thread correctly, that can goof things up to.

Probably just need more oiling before and after use - with say Singer light sewing machine oil.

try this link for a free manual just in case you don't have one
http://www.singerco.com/uploads/download/36952a1312a6d8436174ef874f3662471a946b64.pdf
if the fabric is real light weight you may have to use a stablizer
also check to make sure the needle is the right one for the fabric being sewed..
make sure the bobbin is turned the correct direction, try putting the bobbin in the opposite direction..
if the machine keeps jamming, take it back up where you bought it and show them what it's doing and see if they can help you..

try changing the needle--make sure it's the correct one for the fabric
being sewed
rethread the machine ---using every thread guide
try using a different bobbin
try turning the bobbin over the other direction
clean under the needle plate and in the bobbin area for lint
also could be a timing problem and the machine would need to be
checked at a sewing machine repair shop

Is it getting tangled while you're spooling the bobbin on the top right corner of the Singer 1507 machine? If this is the case, you have to pull the thread through the top tiny hole in the bobbin, and hold on to the thread end. Then click the bobbin to the right to lock it in place, power up your machine. Keep holding the thread as you begin spooling the bobbin. Let go of the thread once the bobbin starts to spin a few rounds and the thread should not get tangled.

if the thread under the fabric is a matted mess
1.the needle thread tension is to loose
2.needle is either to heavy or to fine for the thread
3.check to make sure the thread isn't off the thread take-up lever

I had this same problem yesterday. I took apart the needle tension casing and now it doesn't get tangled or stop. The only thing is the bobbin is not sewing...it looks fine on the top, but the bottom is just loose loops.

If you are getting a thread mess under the fabric, it is a top thread problem.

Remove the top thread completely from the machine.
ALWAYS RAISE the presser foot and rethread from the beginning. Verify the thread path is correct.
Retest your machine and tweak the tension, if needed.

...

Try changing your needle.