My new potting setup.

[belwar]

Well I'm still a beginner with the whole pickup winding jig, but I've been jumping with both feet. Today I got my potting machine (if you can call it that) set up. It was a reasonable price to set up. I used a $40 6qt chicken roaster from sears.com, then got a 3/8" polycarbonate sheet remnant from my local plastics store. I placed the lid on the sheet and traced it out, then cut it out. I placed some adhesive backed rubber weather stripping around the perimiter as well to hold the vacuum in. Then I drilled and taped three holes in the top. I put an inlet and outlet for air on it. Then I put a vacuume gauge on it as well.

Turning it on cups the plastic a fair bit so I'll probably go to 3/4" or 1". I'm measuring about 27.5 for vacuum (VERY strong). The seal is so good all I have to do is turn the vacuum lever on, and close it. The vacuum will stay in for 10+ minutes untill I release it. After 5 minutes it was down to 25.5 on the vacuum gauge.

The roaster is a double insert so there is no hotspots directly on the wax. Tommorow I get to start potting about 15-20 junk coils i've wound.

I think i'm going to try for about 50-60% penetrations. Thoughts/comments on that would be appricated.

b.

[David King]

What are you using for a vacuum pump? Aren't you afraid of crushing the pot or is it some kind of crazy ceramic?

[belwar]

What are you using for a vacuum pump? Aren't you afraid of crushing the pot or is it some kind of crazy ceramic?

Five horsepower Vein style Busch Vacuum pump. Am I afraid of crushing the pot? Hell yeah! It colapses some, but seams stable for now. I'll probably add a regulator to controll the ammount of vaccuum. Honestly I'm a little nervous, but after turning it on, and turning it off 2 dozen times im a little more confident not. Im also thinking about adding a brace in the center. from top to bottom

[Chadheckler1]

This is a newbie question on this thread...but why does there need to be a vacuum? Every time I have potted a set of pickups I just use the stove and a double boiler...

...and what does 50-60% penetrations mean?

You don't have to respond if it is a waste of time, but I am curious if there is a better way than what I am currently doing...

[belwar]

This is a newbie question on this thread...but why does there need to be a vacuum? Every time I have potted a set of pickups I just use the stove and a double boiler...

...and what does 50-60% penetrations mean?

You don't have to respond if it is a waste of time, but I am curious if there is a better way than what I am currently doing...

Vacuum is a way to get wax into the coil very quickly and remove air bubbles from the coil. You can also control the penetration of the wax into the coil. I'm aiming to have the wax penetrate about 50-60% of the way into the coil.

To answer your question, you dont NEED vacuum, but I believe it can give you some easy repeatable results.

[SkinnyWire]

Vacuum is not required. Just depends on what you're after. You can get repeatable pickup results with attention to detail. Potting is just another facet of the game.

[belwar]

Holy crap! It works!!

...and what a difference from 25 to 27.5 vacuume. I have a ton of experimenting to do. If I pre-heat the coil I can get penetration to the core in about 3 seconds at full vacuum submerged. I've never seen anything bubble like that before. I was able to hit that 50-60% mark very easily.

[Chadheckler1]

Sounds sweet!

So you just used your "15-20 junk coils" one at a time and just truned on vacuum, mdified the time interval, cut into the windings, and measured the depth based on the two input variables of time, and amount of vacuum? Are you seeing a pretty consistant temp on your "crock pot"...what temp range are you in...? Is temp a 3rd variable, or is it ok as long as the wax is melted?

[Magnut]

Nice setup,

I have been working on the same issue for a little while. I wanted to share what I have found.

Right now Surplus Center has some things that would help to vacuum pot your pups.

I got this nice little pump for cheap.

The vacuum pump is 135vdc so all you need is a rectifier, though you really don't need one this big. This one is big enough to be it's own heat sink. Add a gage and your set.

[dpm]

^ that's an awesome deal. I'd grab a couple of those if it weren't for the slight location issue

[David Schwab]

I have been working on the same issue for a little while. I wanted to share what I have found.

Thanks! I've been looking for a cheap vacuum pump.