2013 Brother XR-4040What I've been able to find out so far:
Machine opened up and butterflied out.
Main Logic board needed to be removed...
In order to access the upper shaft timing pulley (center with belt).
Timing mark on bobbin race
Reassembled machine stitching fine!
One of my dance sisters bought this NIB for $50 from another dance sister who had purchased it a couple of years ago (I think the original price approached $200). A dance brother was having problems with his machine, so he borrowed this one. Remember, the box was still sealed. He could not get the bobbin thread to pick up, so he brought it to me (and informed our dance sister).
Since I had never laid hands on a machine this new, I was pretty interested in seeing what made it tick. I couldn't get it to pick up the bobbin thread either! So I opened a support case via Brother's website. They responded quickly, and as is usual for such situations, referred me to a portion of their website regarding proper threading, etc. I wrote back and told them that I had worked on and sewn with many, many sewing machines, some of them approaching 100 years old - BUT that I'd review everything one more time. And a question: "Does this machine differ in any substantial respects from any other machine made in the last 100 years?".
The answer came back quickly, that it was pretty much a "standard machine". Ok! So then I took enough plastic panels off the bobbin area to be able to see metal parts I recognized. When the hook passed the needle, the needle was almost at Top Dead Center (TDC). This was obviously wrong, the needle should have been just past BDC at that point in the cycle!
So, here it was, and I didn't have a clue how to even take it apart, much less time it. Didn't want to dive in without documentation if I could help it. Google found me the complete service manual in PDF format, which I downloaded and printed out (double sided, it was STILL very thick). To Brother's credit, this is one of the most EXCELLENT service manuals for anything that I've ever seen. With it, I was guided step-by-step on exactly how to disassemble the plastic case, and how to line up the timing marks. Turned out it was about 120 degrees out of phase between the top shaft and the bottom shaft which are connected with a toothed belt. As seen in the third picture above, the timing belt pulley on the upper shaft is easily accessible once the logic board is removed. It was a simple matter of slipping the belt off this pulley, rotating the upper shaft to the correct position, then slipping the belt back on.
After reassembly, the machine picks up the bobbin thread and sews like a champ. I had fun exploring some of its computer generated decorative stitches!
With regards to Brother, I informed them of what had happened and how I corrected it. They in turn congratulated me, but did want to point out that this would have been covered under their warranty on this model. Which wasn't quite true as the machine had been "sitting around" for well over the 2 year warranty period, plus wasn't owned by the original purchaser anyway; but I won't "ding" Brother on this as they had no way of knowing that. This just goes to show that consumers should really at least test products as soon as possible. Yea, the machine made it out of the factory with an incorrect assembly, that shouldn't have happened. BUT, I'll give credit where credit is due, the service manual is EXCELLENT (Please don't email me wanting it, I don't remember where I downloaded it from, it was NOT Brother's site, use your "Google-Fu"!)!
As for how it is built - it's "good enough". The mechanicals seem well designed and the plastic case/chassis has plenty of molded in bracing for the metal parts. The bad news is that there are exactly ZERO places to really oil this thing - although I tried. This means it won't last nearly as long as any of my antiques will. But as the weak link is the electronic control system, that'll probably fail long before any of the mechanicals get tired. The ease of use and the computerized decorative stitches may very well make a machine like this worth it to many people, most people don't run their sewing machines on a frequent basis unlike my mother who made all our clothes and was stitching on her machine "all the time". Give it 20 years of occasional use and replace it. That's how our consumerist society works these days, for better or for worse.
A bit of trivial serendipity: This machine's model number is XR-4040. The Intel 4040 microprocessor was the second microprocessor ever invented, preceded only by the 4004. I am one of the few people on the planet who has written code for the 4004 and 4040. I imagine the processor in this machine has several orders of magnitude more power than the old 4040!