New Mojo winder

[big_teee]

Here are a few pictures of the Humbucker mounting brackets I made, that I said I would share.
Keep in mind I am not a machinist, and I used scrap plexiglass bar stock I had on hand.
A bit crude, but spins true and works great.
There are 3 sets of holes for 49.2, 50, and 53mm.
The hole in the middle is so I can use the screw and wingnut for anything that can be mounted from the center.
The top bar piece, Adds Support, and greatly helps on flaring, if you tend to be heavy handed on tension Like I can be at times.

[David Schwab]

It looks really nice.

I was worried about it being too loud. I currently power my Schatten with a drill, and it's too noisy!

[rhgwynn]

I currently power my Schatten with a drill, and it's too noisy!

I imagine it gets pretty warm, too.

[big_teee]

DS drill may get warm the Mojo seems to not be effected, and is Continuous Duty.
It has the big 24v 5 Amp power supply, probably doubles as a computer power Supply.
The Winder is totally enclosed, and can't tell if the motor heats up or not, the housing doesn't.
As far as the noise, it is in my Shop, and most other things I run there makes more noise.
Air Compressor, drills, drill press, grinders, etc.
The winder is still quiet enough to listen to the radio, while winding,
In the house it would be quieter than most kitchen appliances, the vacuum, washer, heat & Air, wife's Kenmore Sewing machine, etc.
Some comparison for you guys concerned about noise.
T

[David Schwab]

I imagine it gets pretty warm, too.

It doesn't seem to. It's my old DeWalt variable speed drill that I've had since the 90s. The annoying part is having to hold the trigger in with my left hand!

It's one of those things that was supposed to be temporary, and then I never got around to replacing the motor. Now I'm planning on either building or buying a new winder, so the point is moot.

I'll probably put a new motor in the Scatten and use it for rewinds. I bought it March 2006, so I have certainly gotten my money's worth from the thing!

[Vaughn]

Hi, I wanted to add my experience with this machine to the body of knowledge out there. I have now had two of them, and they have both suffered from a problem that seems to render them unusable for professional purposes. I'm waiting for a reply from the good folks at Mojo, but here is the issue I've encountered with both machines (cut-n-paste from the email I sent to Andy @ Mojo):

As I and my apprentice began using the machine, we noticed that the coils were being wound progressively with less and less winds ...as measured by resistance, inductance ... and even visible to the eye (the bobbins simply were not as full). The strange thing was that it only was happening in counter-clockwise rotation. By the end of the 2nd day in use, we were needing to add apx 1200-1400 ADDITIONAL winds to cc-wound pickups to achieve the expected specs.

Very frustrating ... and has resulted in the loss of a couple of days time in the shop for the two of us ... and a number of pickups too badly under spec to be able to be sold as is.

And again, the problem is only exhibited when winding in CC direction.

Has anyone else reported this, or is it just mine? I'm otherwise satisfied with the machine, and will undoubtedly be buying many more ... provided we can get this figured out and fixed. I chose this machine based mostly on the precision and speed ... and as it is, precision is completely gone.

[Vaughn]

So, here is the email response I just received from Andy at Mojo. For the record, I'm glad they are not just blowing me off ... but I'm also terribly disappointed that they brought a product to market that was obviously not ready. The issue cost me hundreds of dollars in labor and materials ... and I now have a bunch of pickups that will only be sell-able if I decide to cut & rewind them (ugly when they're potted) ... or try to sell them as "under-wound" haha... not really! Any of you out there that have wound pickups on this machine (in CC direction anyway) should be aware that they may in fact be notably underwound

"Hi Vaughn, we found the problem. The encoder wires are susceptible to magnetic interference from the motor and need to be shielded. It only affects the one direction as the encoder wires were bundled with the motor voltage wires, and the manner it was done could lead to the problems you have. So, there are a few directions we can go here. Either (1) I can send you the shielded wire and you can install it, as it will not affect the warranty as I have this s/n on file and the issues with it. 2)We can send you out a corrected and tested unit, and return the one you have or, 3) We can give you a refund on the winder if you choose."

[RedHouse]

Sounds logical and all that, but having build a few units myself now (CNC and PIC uC stepper controlled) I'd bet it's more like a math problem in the program. But what do I know.
(no offense intended to anyone)

[big_teee]

I have one, and like it.
I think it works correctly.
I am going to wind a strat coil to 7000 turns.
Going to record the DCR measurements, cut the wire off, and wind again the other direction.
Record DCR, and compare.
T

[RedHouse]

Ah, well then, Big-T's on it so I/we can rest ...assured.
(no pun intended)

Thanks Terry! peace out.

[big_teee]

I wound two coils.
Instead of the strat coils, I wound 2 soapbar bass humbucker coils.
I wound 2 coils with 5000 turns each of 42 red SPN.
These are hand guided and no auto traverse.
They appear to both be exactly alike, 4.5k DCR each.
My winder seems to be fine!
**edit
FYI, I wound the coil with black and white wires, mounted upside down bottom going.
I wound the coil with red and green wires, mounted standard, I wound it Top going.
End result = two coils both wound CCW.

[John_H]

@Vaughn; from reading your original post it seems that you knew there was a problem almost right away, and you kept on winding for a couple of days. If you burned up a bunch of time and wire, then you own part of the blame. A big part. It also seemed that the folks at mojo were trying to remedy the problem.

...exactly alike, 4.5k DCR each.
My winder appears to be fine!

It probably wouldn't hurt to add the shielding if you don't have it. Those are nice looking coils Terry. Solid work that's only possible with a machine that runs very true, and smooth.

[Vaughn]

For the record, I'm posting in this particular forum because this VERY forum was a large part of what made me decide to choose this winder as an "upgrade" over what I had been using. I figure folks out there doing that very same research will benefit from my frustrating experience with the unit as well as other folks glowing results. I know all to well that whenever you bring up a less than positive issue on a forum you expose yourself to scrutiny ... but I felt it was worth it to add something very substantial to the body of knowledge out there on this particular machine. Sooo, the latest update:

Andy at mojo says there were only four or five winders with the problem ... I just happened to be "lucky" enough to get two of them!

I THINK I like the machine ... and may well end up keeping ... IF they can get me one that I can feel 100% confident in. It was suggested by a forum member here that I ask for a roll or two of wire to make up for the wasted wire; they said "no" but offered 15% off my NEXT order. I'm pondering...

To John H: It was an employee winding ... and I stopped him as soon as we noticed the erroneous measurements. The FIRST time it really burned up a lot of time...

"What the heck, are you sure you set it for 8000 winds? ... yea, I'm sure ... okay then, let's try another one and check the resistance before we cut it ... wow, that's not even close, try adding another 1000 winds ... hummm, closer, but still not there, add another 500 ... almost, let's go for a couple hundred more ... okay, that's close enough ... what the heck just happened? I don't know, somethings definitely not right with that winder ... okay, let's check everything you wound today before we go any further ... dude, all the middle pickups are spot-on ... but the bridge and neck's are like WAY under ... what the heck? ... well, those were all wound CC ... and the middle's were clockwise ... man, can that be it? Is it only wrong in Counter-clockwise? ... okay, let's test that with a duo-sonic set ... and don't snip the coils before sanding & checking resistance ... yep, you were right dude ... had to add about 1700 winds to the CC one."

With the SECOND machine it was more like "it's happening again" ... and we knew exactly what was going on.

[Vaughn]

I decided to give Mojo one more strike before counting them out! Machine #3 is supposed to arrive tomorrow ... guaranteed to be issue-free. I will post here as soon as I'm able to assess it fully.

What it came down to is that both I and my assistant actually LIKE the feel of working on the machine ... and once fully put in production, the machine will run for probably 30-50 hrs per week, something my Schatten & Thomas machines are not really up to ... but the Mojo is supposed to be.

[big_teee]

Hey Vaughn:
Didn't hear you mention the built in gauss meter?
I use the gauss meter a lot, and think it's a nice touch.
Since I got the Mojo machine, I don't often get my other gauss meter out of the drawer.