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Janomelock JL-634D


Rebranded around the world, also known as:
Hobby lock, Riccar, Mammy lock, Portalock.

Possibly circa 1984. Made in Japan.

This machine has been well loved and much used. When I saw it for sale it looked to be a brown colour. In fact, it turned out to be a lovely deep rich red. Of course, that red is a hard plastic, unlike the metal front plates of the older machines. The carry handle is part of the metal chassis, so carrying this machine by the handle feels safe, not like it’s going to break off.

The model is a 4 thread, differential feed machine, probably one of the earliest differential feeds. The green 3 thread machines in this series are more common in this area, as far as I can tell.

I have since acquired a 3 thread version of this design, the Janome lock JL-603A, you can see that machine if you click here.

To change the differential feed you need to open the access panel on the left and move a lever found underneath, after unscrewing it. You really need to have the manual to understand how to adjust the two screws. To change the stitch length, you need to pull out a lever on the left, while turning the hand wheel on the right. That is why the hand wheel has numbers on it.

Without the instruction book, I can imagine this machine would take some time to figure out. To change the needles, you need to have the hex screwdriver that came with the machine. Well, you guessed it…the screwdriver did not come with the machine when I purchased it. I have since worked out what size Hex screwdriver will fit, go to the bottom of this page for info and pictures. Unfortunately, the machine did not come with any of its original attachments.

To access the inside of the machine is very simple. 5 screws on the faceplate and it lifts away easily. This is important, as there are no wicks inside, so to oil the internal mechanism, you really need to access the internal part of the machine.

The on off switch on the side switches only the light on and off, the machine is on at all times that the machine has power from the mains. The handwheel is turned in a clockwise direction (roll top away from you), like many of the early Japanese machines.

This is a beautiful machine and all the metal workings are still perfect. It had a good oiling and clean and runs beautifully. I managed to rethread it and get a lovely stitch, I tried out the stitch lengths on 1, 3 and 4.5, pictures below.

Research has shown me that it is very hard to pinpoint the factory that made this machine, but speaking to other overlocker collectors, it is believed that these machines came from the JUKI factory.

Instruction book to this machine can be found here.

This machine takes the semi-industrial round shank needle, the DBX1 needle system, you can find more information on needles on my VSM Needles page. It is the only overlocker so far in my collection that uses these round shank needles.

These photos are from the internet “for sale ad”, see how brown it looked?

All cleaned up, a nice solid machine from the 1980s.

Final stitches. I am very happy with how smooth this machine is.

Changing the needles

This machine takes DBx1 needles, round shank industrial needles.

(image to the left is from the instruction book that can be downloaded as a free PDF from here.)

As this machine came with no tools, I found it challenging to change the needles. Metric hex keys were either too large or too small. I ordered an imperial measurement Hex key and it fits perfectly. This is the screwdriver I ordered. Screwdriver Hex 1/16″ 5.71″ 145.0mm long

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