Can you help me understand the difference between the juki dnu1541s and the juki du1508ns?

[kgg]

Silverd I looked at your photo showing your thread path and have a couple of observations that differ from my setup:

The thread from your spool to the double hole pin: You are entering in the bottom hole first the existing through the top hole before going to the first multi hole bracket. You should enter your thread through the top hole first then exist from the bottom before going to the first multi hole bracket. What I found worked best for me with both V46 and V138 is to just use the top hole and not snake around into/ out of the bottom hole in the pin. It just added to much tension on the top thread for those thread sizes. Thread size V69 and V92 I can snake the top thread through those holes with no noticeable thread tension problems.

The multi hole thread bracket (4 holes) I usually use three holes for V69 and V92. Top thread down through the first hole closest to the thread spool then down through the third hole and up through the fourth hole before going to the 2 hole bracket on the tensioner. Using V46 and V138 I used just the first and fourth hole in that tension bracket.

As a note the more holes your top thread snakes through the more tension will be placed on the top thread through added tension may cause problems that your main thread tensioner may not be able to compensate for.

Another note is that I did see a youtube video on winding the bobbin thread a while back for the Juki 1541S that was totally wrong. If you are following that video for bobbin winding you will probably going to have poor bobbin thread tension and thread fraying of your bobbin thread. The correct way to thread the bobbin is to poke your thread through one or two holes of the double hole pin then thread it through the hole in bobbin tensioner bracket that is just above the tension discs. the bobbin tensioner is located on the top right of your machine. Then make a loop around the bobbin tensioner discs making sure the thread is seated between the two discs and back out the same hole that your thread entered. Then thread the bobbin and place on the winding mechanism. That funny shaped piece of metal that is mounted on the side of the machine is not a guide. It is a thread cutter that you can use to cut the thread once the bobbin is full which is usually set so the bobbin is loaded to about 80% maximum capacity. The tension of the thread for the bobbin can be adjusted by tightening the two discs together or apart by turning the white knob clockwise or vise visa on the bobbin tensioner.

The above is just a starting point and may vary for your machine depending on the thread size (V46 to V138), type (bonded polyester vs bonded nylon), thread colour (white vs black), thread manufacturer (Chinese vs North American), thread spool size (8oz vs 1lb) and material being sewn.

Your thread spool support frame, it wasn't really clear in the photo but it appears that the thread guide bracket that the thread exits before going to the double hole pin on the machine seems a little low. I think the typical way is to have your spool platform mounted fairly close to the table top and the thread bracket mounted at least twice the height of the thread spool above the spool platform. If your thread spool is 8" tall the thread bracket would be mounted about 24 " above the spool platform so the thread can unwind better from the top of the thread spool. There has been also been a fair bit of discussion on 8 oz thread spool problems and spool platforms that help.  

I think I saw a needle positioner on your machine. I don't have that feature so someone else can discuss the pros / cons / setup.

kgg

[Silverd]

Kgg.

Thank you so much for this latest info.  Wow.  I'm blown away that you took the time to help me.  You mentioned in a previous note to make sure bobbin is loaded correctly in bobbin case.  Oops!  It was not according to the Juki manual and I have since corrected that.  I'll re-thread the machine per your latest recommendation and go from there.  Obviously the bobbin direction being wrong was the primary cause of my issues but thread tension is also contributing.

[Wizcrafts]

40 minutes ago, Silverd said:

Obviously the bobbin direction being wrong was the primary cause of my issues but thread tension is also contributing.

Bobbins are usually loaded so they feed against the direction of rotation of the hook and bobbin case. This means that their thread make a sharp reverse turn as it feeds out. When you start and stop quickly the bobbin tightens its thread  rather than letting it loose.

A lot of machines have star or round shaped springs inside the bobbin case to prevent run on. These are called anti-backlash springs. They can compensate for feeding the bobbin thread the wrong way, including on purpose for a smoother feed.

[Silverd]

Very cool.  I did not know this.  Any effect on how the back side stitch lays down?  

I'm also used to a much greater bobbin tension.  Using only the weight of the bobbin in the case as a means to set the tension seems low.

 

Silverd

[Wizcrafts]

Set the bobbin spring for a modicum of pressure on the outgoing thread. Balance the knots with the upper tension disks and thread path. The bobbin is too loose when loops form on the bottom of the work despite the knots being centered. I tend to run fairly loose bobbin tension most of the time. I only crank it up if I want the thread to be pulled deep and tight into the top and bottom. This puts a lot of strain on the take-up parts.

[Silverd]

My equestrian stitching experience pushes me toward tight stitching.  I understand the principle of lock stitch but have no experience on this machine. It's more difficult to tune a machine when you don't know what ito should be doing!

I appreciate your attention to this matter.  It's been very helpful.

 

Silverd

[Silverd]

23 hours ago, kgg said:

Silverd I looked at your photo showing your thread path and have a couple of observations that differ from my setup:

The thread from your spool to the double hole pin: You are entering in the bottom hole first the existing through the top hole before going to the first multi hole bracket. You should enter your thread through the top hole first then exist from the bottom before going to the first multi hole bracket. What I found worked best for me with both V46 and V138 is to just use the top hole and not snake around into/ out of the bottom hole in the pin. It just added to much tension on the top thread for those thread sizes. Thread size V69 and V92 I can snake the top thread through those holes with no noticeable thread tension problems.

The multi hole thread bracket (4 holes) I usually use three holes for V69 and V92. Top thread down through the first hole closest to the thread spool then down through the third hole and up through the fourth hole before going to the 2 hole bracket on the tensioner. Using V46 and V138 I used just the first and fourth hole in that tension bracket.

As a note the more holes your top thread snakes through the more tension will be placed on the top thread through added tension may cause problems that your main thread tensioner may not be able to compensate for.

Another note is that I did see a youtube video on winding the bobbin thread a while back for the Juki 1541S that was totally wrong. If you are following that video for bobbin winding you will probably going to have poor bobbin thread tension and thread fraying of your bobbin thread. The correct way to thread the bobbin is to poke your thread through one or two holes of the double hole pin then thread it through the hole in bobbin tensioner bracket that is just above the tension discs. the bobbin tensioner is located on the top right of your machine. Then make a loop around the bobbin tensioner discs making sure the thread is seated between the two discs and back out the same hole that your thread entered. Then thread the bobbin and place on the winding mechanism. That funny shaped piece of metal that is mounted on the side of the machine is not a guide. It is a thread cutter that you can use to cut the thread once the bobbin is full which is usually set so the bobbin is loaded to about 80% maximum capacity. The tension of the thread for the bobbin can be adjusted by tightening the two discs together or apart by turning the white knob clockwise or vise visa on the bobbin tensioner.

The above is just a starting point and may vary for your machine depending on the thread size (V46 to V138), type (bonded polyester vs bonded nylon), thread colour (white vs black), thread manufacturer (Chinese vs North American), thread spool size (8oz vs 1lb) and material being sewn.

Your thread spool support frame, it wasn't really clear in the photo but it appears that the thread guide bracket that the thread exits before going to the double hole pin on the machine seems a little low. I think the typical way is to have your spool platform mounted fairly close to the table top and the thread bracket mounted at least twice the height of the thread spool above the spool platform. If your thread spool is 8" tall the thread bracket would be mounted about 24 " above the spool platform so the thread can unwind better from the top of the thread spool. There has been also been a fair bit of discussion on 8 oz thread spool problems and spool platforms that help.  

I think I saw a needle positioner on your machine. I don't have that feature so someone else can discuss the pros / cons / setup.

kgg

Have spent now several hours attempting to tune this machine into sewing like I expected,  and all things considered i have likely gotten it to stitch as well as it is going to but didn't know it.  The photo is of the backside stiches from my Chinese 441 thick white thread and this machine.   Is this normal for the jukie?  If so, I've made a mistake.

Silverd

 

10 hours ago, Wizcrafts said:

Bobbins are usually loaded so they feed against the direction of rotation of the hook and bobbin case. This means that their thread make a sharp reverse turn as it feeds out. When you start and stop quickly the bobbin tightens its thread  rather than letting it loose.

A lot of machines have star or round shaped springs inside the bobbin case to prevent run on. These are called anti-backlash springs. They can compensate for feeding the bobbin thread the wrong way, including on purpose for a smoother 

Edited August 4, 2019 by Silverd
More words

[kgg]

 

10 hours ago, Silverd said:

Is this normal for the jukie?  If so, I've made a mistake.

I would not be pleased with that stitch and no it is not normal for any Juki. I have seen that stitch happen when the thread was seated properly between the main tension discs.

A suggestion would be to check that the main tension discs are working properly and the thread is seated deep within.

As a note I always thread through the discs with the tension on the discs released. To release the tension on the discs by raising the presser feet by using either the level on the back of the machine or the knee lift.

For ease while checking the tension discs and re-threading lock the presser feet by using the rear on the rear. First remove the thread from the needle or you are going to have a real thread mess. First you should be able to separate the discs away from each other. If you can great, the thread may have not been seated properly. Then hand wheel the machine through a cycle or two, you should see that the discs tighten against each other and then relax the tension. If not you may have over tighten the main tension on the knob or there is a problem with the main tensioner / operating assembly.

4 hours ago, Starwind0 said:

Mercury

My understanding of the Mercury sewing machines is that they were clones back in the 60's, 70's before the Chinese made an art out of cloning.

kgg

[Elsee]

Will the 1508 be good for heavy leather handbag sewing or is there something better?

[Northmount]

9 hours ago, Elsee said:

Will the 1508 be good for heavy leather handbag sewing or is there something better?

You have tagged onto a very old thread, asking a non-related question.

Start a new thread in Leather Sewing machines.