Click Clack

The Brother DB2-B791-015 was having some maintenance issues while finishing up the skunk and the NFCO. Or at least it was making some noise while the stitching for the main strap(s) were being sewn in. Of course this is probably the heaviest stitching that takes place on the Brother due to the 2″ dive belt webbing which is used – in conjunction with the Coats&Clark “button&carpet” thread, and the #21 gauge needle. These materials together take a lot of punching power and require a heavy press of the foot too, which is partly why it was so alarming that the Brother would be making the clickity clacking noise. You would think that even if something were loose, that under that much pressure it would not have that much room to wiggle. Not so, the machine was definitely making a noise that needed to be found. Essentially it sounded like the feed dog was loose, and rattling while it fed the material: or the feed dog was somehow out of adjustment and actually hitting the bottom side of the throat plate on it’s upswing. However, if the feed dog was hitting the bottom side of the throat plate it would not be a rattle-like noise, but instead a thud (if you will). Also, the throat plate was clearly tight, so it wasn’t that.

The first thing to come off was the face plate on the end of the DB2 head. Behind this plate, is the needlebar, and the presser (foot) bar, with their assorted clamps and driving mechanisms – all of this seemed to be tight and secure, so the face plate was re-installed. Now it was time to dig in a little and lift the massive (in terms of density at least) Brother DB2-B791-015 head off the table and take a closer look. The approach was to take torque-inventory from the inside, moving out, to be as thorough as possible: in other words, all the accessible nuts, bolts, screws, hex’s, etc. were checked for proper torque starting from as far away the hand could reach, slowly moving in towards the feed dog and throat plate. No time like the present. Unfortunately (or fortunately), there was not a loose screw to be found. Even getting into the feed dog and feed bracket, everything was tight. The only thing that had any play in it was the carriage for the bobbin case, which is situated within the rotary hook assembly. This little bit of play was quite small, and seems like it couldn’t have made the rattling that was heard, not to mention – all of the screws around this were quite tight. The other thing about the carriage for the bobbin case is that it is free-floating (so it can spin) which means that it always has a little bit of play.

That said. It is hard to say, just where this noise was coming from. Maybe it was a matter of stress on the machine? Maybe it is time for the Needlefeed & Company to think about a walking-foot? Since the tear down, the noise has been pretty much non-existent, which we can only conclude that it was simply the strain between the dive belt webbing and heavy needle’ing. This kind of situational rattling may take place again, but as long as we know that everything is tight and together, then maybe there is no need for alarm.

Jam

The Brother received a rather jarring and disruptive blow this weekend. Perhaps this was a glaring moment of communication on the part of the Brother. With the last few projects being alterations, this abrupt ending could have been a call to begin again from scratch. A moment of due force and deliberate gesture composing all of the Brothers being into a powerful expressive code. Corralling and instigating all the most macro waves of the machine into a severe display of energy. This instance cajoled by a determined mind of heavy thread and a heavy needle weaving their way through an area of well mannered but unpredictable denim. Thus resulting in a massive jam between the feed-dog and throat-plate. It was quite obvious at first that the needle was well situated between something, or had somehow pierced the material layers, broken and then pulled back up like a grappling hook into the most peculiar of nooks – as the needle pulled free of the needle-bar marking the anchor between the two, submissive by pressure. It was surely a high sign of ultimate and searing tension between componentries when even the mightiest combination of hand and pliers could not move the needle away and free of the denim folds. With the presser foot detached for ease of repair, the only resort was to cut the needle out. A quick diagonal shearing of the top side of the needle was made and the denim carried away to expose a huge amount of potential radiating from an amalgamation of throat-plate, needle, and feed-dog. Upon this generous action, this clash, this cramming of abject courses, which brought the Brother to such a catastrophic halt, the needle had swayed wayside, avoiding the central positioning and in one giant punch managed to wedge itself with the utmost strength between the two single mechanisms. After excising the throat-plate and freeing the bit of remaining needle the flexibility of the materials at hand became immediately apparent. For it was luck that only the throat-plate made the move to allow the needle to settle in such a violent way, maybe the feed-dog was the most stubborn after all. What had once seemed like an unrelenting structure – now permitted itself to show lenient character – tolerable of its environment in full. Only a small amount of interaction was needed to situate the throat-plates tracking elements back to approximate their original position, questioning the spring like quality of what was perceived to be a perfect harmony of rigid tooling for fluctuating machinery.

Thread Trimmer

Before we continue on, it is probably good to get out of the way, what the thread trimmer is. In the picture (without text overlay) you can see a small elliptical like washer with a hex bolt in its center, and an arm below it, next to the feed dog, this is the thread trimmer (probably like a top “cap” [?]). Essentially the thread trimmer is a small cluster of bushings which are driven by a simple mechanism to control a small knife. When the thread trimmer is activated it tells the knife to sweep across the thread – underneath the throat plate (or needle plate, what the material is running over, which has the grooves cut for the feed dog to pass by) – and trim the bobbin thread. How it trims the upper thread coming in from above is unclear. What a thread trimmer is good for is that; it saves a lot of time from having to constantly pull the fabric out and trim each side separateley (after your seem is made), it cuts very close to the fabric (probably closer than a human can), and it leaves the remaining thread at the optimal length to begin sewing again (this saves thread, and saves the person sewing from having to always pull a little excess out before laying down the next seem).