[Production example] Westminster JB pickup rebuild

This is an example of a pickup that was repaired and made at Nekodamari Kobo.

westminster JB pickup rebuild

We received an inquiry from our website about a request to rewind the pickups. The equipment in question was a JB pickup made by a manufacturer called Westminster.

The condition of the item was not good when it was handed over to the customer, so the customer wanted to repair it and continue using it. We started by gathering information to determine whether or not it could be repaired.

It seems to be a very old product from a Japanese brand. If it was a standard specification, it would have been possible to rewind it, but when I searched online for similar models and looked closely at the pickup, I noticed that it was installed in a slightly strange way.

There is no cover, and it looks like it is attached directly like the P90, so it is not a standard specification.

When we checked with the owner, we found out that it was attached with screws without a cover. Since it also seemed to have a broken wire, we decided to have the actual item sent to us so that we could carry out a detailed diagnosis.

The cost varies depending on the method used, so we provide a rough estimate before shipping and then have the item shipped once you have approved it.

◆ Repair proposal details

1. When the repair is completed with minor adjustments and modifications to the wiring

Simple repair cost: Approx. 2,000 yen + tax

2. If the diagnosis shows that repair is not possible

Only return shipping charges will be charged

3. When the entire film needs to be rewound

Since it is a two-piece single coil configuration, the estimated price is 10,000 yen + tax

4. When the original material is damaged and needs to be remade

The cost of materials will be charged separately, approximately 13,000 yen + tax

This time, during the repair, I was only able to touch the pickup.

■ Start diagnosis Identify the cause Check power supply

When I checked the pickup when it arrived, it was completely disconnected.

An even bigger problem with rewinding is the deformation of the hobbin. Since there is no cover, there is no support or protection, and the hobbin seems to be attached by screws pressing down on it from above, so pressure is applied to the screws, causing it to bend.

As you can see, the copper wire is wrapped around the inside, protected with paper tape, but due to drying, etc., it is no longer of any use. In this state, if you accidentally interfere with the copper wire when trying to attach or remove the screw, it will break and the wire will be disconnected. Since the resistance value cannot be measured, there is a high possibility of an internal disconnection.

■Continuation: Diagnosis Diagnosis required for rewinding

It is a complete failure and cannot be used as it is, so we will perform a diagnosis to rewind it. In conclusion, it was not possible to rewind it.

The reason was that the hole pitch for mounting to the winding machine did not match. When I inherited the winding machine, I also received several types of jigs, but none of them were compatible.

・If the installation is not possible, it will be difficult to rewind stably.

- It is impossible to fix a deformed Hobin

There are structural disadvantages

For the reasons stated above, rewinding is not possible, so we will switch to the perspective of making a new one (rebuilding).

Confirmation to the owner

I have contacted the owner here.

・We have confirmed the arrival of the package, but it may be difficult to rewind it.

・Due to structural disadvantages, if we were to rebuild it, the cost would likely exceed the previous provisional estimate.

We received a quick reply and were informed that although it was not an exact replica of the original, the condition was good enough that it could be used with confidence, and that it would not be a problem even if the repair costs exceeded the estimate, so we began designing the rebuild.

■ Rebuild Redesign of structure

If you remake the hobbin as it is, it is possible to rewind it to a state close to the original.

However, the completed pickup will likely gradually deform as it endures the pressure of the screws and is exposed to the outside air. It would be a heartbreaking story if you went to all the trouble of rebuilding it only to have it break someday.

Therefore, we came up with a proposal to attach a special part to the inside of the hobbin to reinforce the structure so that it could withstand the pressure of the screws.

When we adopt reinforcing parts, it becomes a direction that deviates from the original, so instead of being bound by existing products, we decided to take an additional approach and use thin copper wire, and also designed and added a special cover.

Since the pickup cover is a repaired item, we asked the owner whether he would prefer no engraving or ``nekodamari.work'' engraved, and he requested ``nekodamari.work'', so we had it engraved.

Confirmation to the owner

At this point, we will provide the owner with a quote and confirm it again. This will be the final confirmation of the direction of the repairs.

- Create a new product with the same structure as the original.

Estimate: 13,000 yen + tax

- The parts and covers designed above are created using a 3D printer, and then rebuilt into a pickup with a strong structure.

Estimate: 15,000 yen + tax

■Rebuild begins with reinforced structure

We quickly received positive feedback on the direction of a pickup with a strong structure, and we continued working. We used a 3D printer to print the support parts and cover.

We hammer in the pole pieces and assemble the supports.

The effective width of the coil winding is narrower than the original pickup because of the cover attached. Therefore, we rewound it with 0.05mm green enamel, which is thinner than the original. The resistance value has been adjusted to be modest.

Rebuild complete! Difference from custom-made products

The rebuild is complete after installing the lead wires, potting, and putting on the cover!

Almost all of the items have been newly made, so they are essentially made to order, but at Nekodamari Kobo we see this as something different.

It is correct to say that this rebuild was only necessary to "repair the structural weaknesses as an extension of the repair." Therefore, there is no freedom of choice, such as "the number of turns should be about XX" or "the material should be that" as with custom-made products.

When we check with the owner, we get their approval, but we check the effective width and select the number of turns. We cannot choose the color of the 3D printer output. Also, since rebuilding is based on the original, it is important to remember that it will not be a completely different product.

It would have been smooth if a simple rewinding was possible, but we wanted to deliver a pickup that could be used with as much peace of mind as possible, so we decided to rebuild it.

We are grateful to the owner for his prompt response to all our inquiries and his willingness to accept the request, which enabled us to carry out a very educational repair.

Summary: Cost, specifications, and duration

details of repair	Rebuild pickups
Repair specifications	Rebuild of westminster JB ・New production of Hobin ・3D printer-made special parts ・3D printer-made special cover Specification: Alnico 5 green enamel 0.05mm Bridge only RWRP Resistance value: approx. 7k
Repair cost	15,000 yen + tax
Dear Owner, Amount of burden	16,500 yen + postage fee for one shipment (Letter Pack Light)
accessories	none
Repair period	On average, it takes about 1 to 2 weeks. This time: 3 days for diagnosis, 5 days for rebuild work
Warranty details	Free repairs when defects occur within the normal range of use

Thank you very much for your request. If you have any inquiries regarding pickup rewinding, please feel free to contact us using the inquiry form.

Nekodamari Kobo Co., Ltd.