Top load bobbins and needle guide

[MainiacMatt]

In my quest for a leather sewing machine, I spoke to the owner of a sizeable industrial machine dealer that's well regarded in these parts.  Guy has been around a long time and sells and services all the major brands.

To make leather upholstered furniture cushions, I described the machine parameters I was look for as:

• needle feed/walking foot
• up to #138 bonded nylon thread
• stitching up to 6 layers of 3 oz. leather (4 for sewing piped edges, 6 at the piping splice)
• servo motor with slow speed

As we discussed various machines, he advised me to stay with a top loading bobbin model as they have a needle guide (not sure what a needle guide even is) and that when stitching multiple layers of leather the needle will tend to flex and there's potential to damage the hook in a front load bobbin machine.

So, my question to the forum is... how much of an issue is having a needle guide when stitching leather upholstery?  I've seen that the needle does tend to flex to the side when I've sewn tight up against the piping. Yet there are a lot of end loading bobbin machines out there being used by leather workers and  I'm having a hard time envisioning that they're all getting damaged for want of a needle guide.

Inquiring minds want to know...

[kgg]

The 3 layers of 6 oz leather or 18 oz in total ( just over 1/4 " thick) with V138 thread should be able to be handled by almost all of the upholstery class flatbed machines like your Juki DNU-1541S and clones but most load the bobbin from underneath the machine. To get the top bobbin loading you need to go up to a Juki LU-1508 class machine or clone. The Juki LU-1508 machine also has a larger bed and a double tensioner and is an overall heavier duty machine.

Another option would be to go with a upholstery class cylinder bed machine in the Juki LS-341 or LS-1341 (newer version) or clone where the bobbin is loaded from the top and a flat bed attachment.

3 hours ago, MainiacMatt said:

I've seen that the needle does tend to flex to the side

My opinion of needle flexing is it has a lot to do with the needle size selected for the thread size, the presser foot on the machine and the thickness / toughness of the project. A lot of times it usually be solved by going up a needle and at a slower speed to give better control of the project to prevent side to side movement. The speed of the machine with a servo motor still maybe to much and the machine can be further slowed down by installing a speed reducer pulley.

What machines are you looking at (new or used) and what is your budget?

kgg

 

[MainiacMatt]

Thanks for the reply.   I spoke to another dealer, who said front load bobbin machines do have a needle guide, but it’s different.  

Does any of this make sense?  Or is it a non-issue?

[Wizcrafts]

4 hours ago, MainiacMatt said:

Thanks for the reply.   I spoke to another dealer, who said front load bobbin machines do have a needle guide, but it’s different.  

Does any of this make sense?  Or is it a non-issue?

I think part of the silence is because most of us sew thick leather with large enough needles that flexing is a non issue.

That said, I do have several machines setup with #69 thread and #18 needles. These are deflect-able. Occasionally, I will break or bend a #18 needle if it hits metal, or an uneven edge or layer that it just encounters. None of my machines have any special guide to protect my ten cent needles.

If you plan to thread up with #138, top and bottom, you will probably want to use a #23 needle. That is hard to deflect.

[Constabulary]

With needle guide he probably means the needle deflector.

[MainiacMatt]

His point was that I’d want a “needle guide” to avoid damaging the hook, should the needle flex.  

I’m visiting to look at machines next week.  It’ll probably all make sense then.  

[kgg]

1 hour ago, MainiacMatt said:

I’m visiting to look at machines next week.

That is an excellent idea. Take along a sample of what you want to sew and if you can afford it buy a brand name machine rather then a clone.

Buy Once, Cry Once

kgg

[Constabulary]

This thingy here is the needle deflector on machines with top loading bobbins. I think Singer called them needle guard. There are no other extra needle guides except the needle hole in the feed dog (if you want to consider this as a guide) and the needle hole in the inner foot (if not open to the front). I think that was just misunderstanding (guard... guide...) or saying something but meaning something different (that happens) - I think he meant the needle deflector / needle guard.

 

 

EDIT:

This is an extract from the Singer 111 manual:

 

Edited January 22, 2023 by Constabulary

[MainiacMatt]

8 hours ago, Constabulary said:

I think he meant the needle deflector / needle guard.

Thanks for the detailed reply.  That's got to be it....  (the guy had a pretty good Massachusetts accent and  scribbled down guide in my notes).

So now that I know the correct terminology, is it a big deal that bottom bobbins don't have this same style needle deflector/guard?  Seems like there sure are a lot of them out there, so  it's hard to imagine that it's a huge shortcoming.

Edited January 22, 2023 by MainiacMatt

[DonInReno]

8 hours ago, MainiacMatt said:

So now that I know the correct terminology, is it a big deal that bottom bobbins don't have this same style needle deflector/guard?  Seems like there sure are a lot of them out there, so  it's hard to imagine that it's a huge shortcoming.

I wouldn’t worry about that - machines of both types have great track records when used correctly.  None of the upholstery designs could be considered fragile and some form of needle protection is built into all of them.

Good sewing technique and good quality needles of the correct size will prevent 99% of problems with needles flexing into places they shouldn’t be and damaging things.  A speed reducer will help even more because you’ll have more control and be less likely to have the material pull the needle one way or another.

Having said that, some designs are more idiot proof than others.   I picked up one horizontal bobbin machine that had a history of needing a hook every few years due to needle strikes, which didn’t seem right.   Digging into it, the problem was a combination of operator error (thin needles and thread on rather thick upholstery) and error on the part of the guy maintaining the machine who installed poor quality hooks that were a bad design that crowded the needle and we’re easily damaged.

If you get a used machine of any brand, or a new inexpensive brand, the odds of a multitude of issues goes up - just keep in mind that if you are breaking or bending a lot of needles there is probably a reason that shouldn’t be too hard to figure out.  Buy good quality needles and more than you need and change them out at the first sign of a problem - a bent needle just ups the odds of damaging something.

Best of luck - you’ll have fun sewing with that type of machine - easy to learn and you’ll never outgrow it for other types of upholstery.