potting without pro setup?

[kayakerca]

And the very title here...Potting without a pro setup?

I made pickups as a pro for several years without "a pro setup"! OK, it got more pro as the years advanced, but the earliest years of Alembic pickups were made with a scant few hundred bucks in gear. Yes, I got very lucky very early in the game, but you can still set up to make pickups for less than the cost of the computer you're using to read this post.

Could agree more. You can make pickups with very little $$$$ invested in gear. And in Chuck H's OP, we are talking about potting one set of P90's, so an investment of NIL is the way to go.

But speaking as a true beginner, you don't have to be a pro to be willing to spend ~ $125 on a vacuum pump, a small crock pot, a bit 1/2 lexan (for a new crock pot lid) and a brass fitting, you just need to be a beginner with a little OCD and a near uncontrollable desire to play around a bit. As a hobbyist, I find there's as much fun in making pickup winding gear as there is in making pickups.

[Chuck H]

And in Chuck H's OP, we are talking about potting one set of P90's, so an investment of NIL is the way to go.

I've potted about a dozen pickups with my coffee pot now. Works brilliantly!

[David Schwab]

Here's my new wax pot:



It has 4 temperature settings, and also a standby and melt mode, and holds 8 pounds of wax. Not that I need that much in there. Unlike the last plastic unit I had which started leaking, this is all steel construction. Cost me $112.

[kayakerca]

Here's my new wax pot:

It has 4 temperature settings, and also a standby and melt mode, and holds 8 pounds of wax. Not that I need that much in there. Unlike the last plastic unit I had which started leaking, this is all steel construction. Cost me $112.

Nice pot David!

My wax potting rig was ~ $130. $80 for the pump, $25 for the gauges and lines (gauges not necessary for a hobbyist like me) $10 for the crock pot, ~ $15 for the new lid and brass fitting.

I can't put in 8 pounds of wax, but I can pot 3 single coil pickups in 15 seconds! If I ever had the requirement (which I never will), I might be able to do ~100 pickups potted in an hour.

Nothing "pro" about it, just a tiny bit of OCD.

[David Schwab]

That's cool!

I used a small crock pot for a while, but it got too hot and would melt the bobbins! This is larger than I need, but I can leave it running all day.

I don't use vacuum, but I leave them in for about 10 minutes and that does the trick. I put a bobbin in and wind the next one.

The wax penetrates all the way to the center of the coil. The pot, but not the lid, is very sturdy, so with a new lid I could hook it up to a vacuum.

[kayakerca]

That's cool!

I used a small crock pot for a while, but it got too hot and would melt the bobbins! This is larger than I need, but I can leave it running all day.

I don't use vacuum, but I leave them in for about 10 minutes and that does the trick. I put a bobbin in and wind the next one.

The wax penetrates all the way to the center of the coil. The pot, but not the lid, is very sturdy, so with a new lid I could hook it up to a vacuum.

My little pot runs a too hot on low as well, so I hook it up to a small variac which let's me control the temperature very nicely. I have no need for a vacuum potting rig myself. I did it "just because" sort of thing.

[Chuck H]

Vacuum potting seems to be unnecessary with hot wax (about 150*). Like David said, the wax penetrates all the way into the bobbin. There can still be some air pockets though. Agitating the pickup and/or just flipping it on end and upside down will usually release them. I know, I've seen it. Vacuum potting makes this step unnecessary. Vacuum potting is also a good idea for cold potting with various plastic formulas, catalyzed or otherwise. I've done a few pickups like that. I used a mayonnaise jar with a hand pump siliconed into the lid for evacuating air . Watching the bubbles come up as you pump is very gratifying. Wax potting is much cleaner and easier IMO.

[kayakerca]

I used a mayonnaise jar with a hand pump siliconed into the lid for evacuating air . Watching the bubbles come up as you pump is very gratifying. Wax potting is much cleaner and easier IMO.

If I used the vacuum pump from my potting rig on a mayo jar with a tin lid, it would spontaneously implode.

[Tom Phillips]

If I used the vacuum pump from my potting rig on a mayo jar with a tin lid, it would spontaneously implode.

I can't say about a "mayo" jar but if you use a mason jar it will withstand the vacuum.

[kayakerca]

I can't say about a "mayo" jar but if you use a mason jar it will withstand the vacuum.

Not if it's got a tin lid.

[Steve A.]

If I used the vacuum pump from my potting rig on a mayo jar with a tin lid, it would spontaneously implode.

As a former HVAC service tech we used vacuum pumps that would evacuate systems down to 40 microns as I recall. I never thought of using a hand pump for a potting rig but I think it would do the trick.

Steve A.

P.S. Harbor Freight has some very inexpensive vacuum pumps. A few years ago they were selling a vacuum pump for $30 or 40 that you would connect to your air compressor (I didn't have a compressor so I passed on that.)

[kayakerca]

As a former HVAC service tech we used vacuum pumps that would evacuate systems down to 40 microns as I recall. I never thought of using a hand pump for a potting rig but I think it would do the trick.

Steve A.

P.S. Harbor Freight has some very inexpensive vacuum pumps. A few years ago they were selling a vacuum pump for $30 or 40 that you would connect to your air compressor (I didn't have a compressor so I passed on that.)

I use a single stage 3 cfm 1/4 hp vacuum pump on my potting rig. It may not suck the paint off a car, but it will remove every last bubble of air from 3 single coils in in about 20 seconds.

You can get them for $65 on eBay.

P.S. Steve

I spent 4 summer season's doing component work on portable air conditioner units back in the mid 70's. Back in the day when you just opened the low side line, cut open the dryer with a set of side cutters and just let the R22 be free.

[Steve A.]

I spent 4 summer season's doing component work on portable air conditioner units back in the mid 70's. Back in the day when you just opened the low side line, cut open the dryer with a set of side cutters and just let the R22 be free.

Up until the mid-90's they sold freon discharge hoses in 25' and 50' lengths for blowing out the charge of rooftop units.

Irrelevant off-topic excursion... The freon laws passed in the early 90's were largely bullshit to protect the vested interests of Dupont and other refrigerant mfgs. R12 is very nasty- it acts as a catalyst in destroying ozone; when the reaction is done the R12 molecule is intact so it can then destroy another molecule of ozone. R22 is not so bad- one molecule of R22 can only destroy something like 3 molecules of ozone and after that it is destroyed.

The incentive behind the laws was basically that Dupont's patent on R22 had expired and it was being manufactured in Japan and India. With the law requiring the use of recovery gear Dupont, et al, made sure that recovered R12 and R22 was not being sold as new so all freon jugs had to have one way valves so that an empty tank could not be refilled. It was a real bummer when you were up on a roof with a 30lb of R22 only to find that the one-way valve was defective and would not open...

Getting back to vacuum pumps you do want a dual-stage pump for HVAC work but a single-stage should work just fine for potting or other industrial-type uses. I was going to have my ex-bosses save me a vacuum pump that worked but could not pump down enough for HVAC work. But I'll check out eBay as you suggest.

Steve

P.S. Do you ever want to blame spell-check for typing in the wrong word only to find that spell-check had been turned off and it was you who screwed up? Darn!

[Bruce Johnson]

Here's the "Pro" setup for potting with CPES. Not a whole lot of investment involved. I mix up the Smith's MuliWoodPrime in the plastic cups, then apply it with a wool dauber (Tandy Leather). The second cup catches most of the excess. I daub it on maybe 4 times, and it's fully soaked in to the core. Then the coils hang there and dry for about 6 hours.

[tedmich]

FYI this cheap unit from Harbor freight does a pretty good job turning a standard air compressor into a vacuum pump


$16