Looking for a good vacuum...

[GET MO]

I was finna get the fjc 3.0cfm model #6909. Anyone have experience with this pump? Its about $100 and seems fit to do the job...

 

[CarefulGrower]

I have it, works well. Even better (worse actually, heh) it's done 100+ purges with the original oil.

Puts either my bel art or skillet top chamber at -29.9 in under 40 seconds. A little loud from -20hg through -29.9hg, but it's a only a few seconds usually, and nothing worse than a vacuum cleaner or so when it's at its loud point.

 

[HighBurn8]

That vac pump is only a single stage and can get pretty noisy...

I was just checking prices today and seen Harbor freight is having a sale right now on their 3cfm two stage for only $140.

Use this coupon and get an additional 20% off bro....

http://www.google.com/url?sa=t&rct=...nxRwedLjXWnpBcfJA&sig2=qjJhrm96LVkNvDkpBqjkbw

I'm buying one this weekend.
Peas, H8

 

[PuertoviejoKL]

I too am looking for a 2 stage pump... I'll check out what HighBurn posted but are there more options out there people feel comfy recommending?

 

[walt cunningham]

i would go with american made if possible. yellow jacket or jb make great pumps, jb platinum if you want the best!

 

[Gray Wolf]

I too am looking for a 2 stage pump... I'll check out what HighBurn posted but are there more options out there people feel comfy recommending?

For most applications, a single stage is more than adequate. Most of what is going to happen, will happen long before you stop measuring in inches of mercury and start measuring in microns.

We use our 6.2 cfm CPS single stage and 5 cfm two stage Robinaire interchangeably, though the larger pump is faster.

We don't however cold boil with them without a cold trap, as the solvent dillutes their crankcase lubricant, but use a military surplus MASH rotary vane pump instead, which has sealed bearings.

All of the convential vacuum pumps that I have ever been around, are noisy under certain conditions, including the Rootes supercharged Stokes pumps we used on vacuum furnaces and inert atmoshphere welding chambers in industry. You can tell at what stage vacuum they are at, just by listening to them.

As for US manufacturer. As a Euro/Native American mutt, I prefer to buy American to keep the money at home, but we US Americans need to get our act together, to be anywhere close to competitive on some items.

The cheap "furrin" CPS is the original vacuum pump that I picked up to experiment with and has half a decade on it and lawrd knows how many hours. Too soon to tell if Robinair is as reliable, but I did note that the used $5000+ refrigerant recovery sytem and recycle system that I originally investigated the design of, was made by Robinair for Chrysler Corporation, and it had a fair number of trouble free hours on it, so they aren't fly by night.

 

[GET MO]

We don't however cold boil with them without a cold trap, as the solvent dillutes their crankcase lubricant, but use a military surplus MASH rotary vane pump instead, which has sealed bearings.

.

What does "cold boil" mean? can you elaborate on this a little bit or send me to a thread that explains all this in detail? I feal like everyone speakin a different language... Hopefully Ill be an expert soon.

I went ahead and got the fjc 3.0 cfm because a friend had a good deal on it, now I need whatever components in order to get ta purgin. do I just need a hose and a suction cup or is it a lot more to it?

Thanks yall for the help. much appreciated!

 

[CarefulGrower]

What does "cold boil" mean? can you elaborate on this a little bit or send me to a thread that explains all this in detail? I feal like everyone speakin a different language... Hopefully Ill be an expert soon.

I went ahead and got the fjc 3.0 cfm because a friend had a good deal on it, now I need whatever components in order to get ta purgin. do I just need a hose and a suction cup or is it a lot more to it?

Thanks yall for the help. much appreciated!

You can either buy or build a chamber and adapter.

Ebay for a chamber all ready to go, hook up to pump and done (though a 2nd valve helps, the seller will add one if you request, featured on bigger absent on this smaller one).
http://www.ebay.com/itm/1-5-Gallon-...349&pid=100011&prg=1005&rk=1&sd=130860754314& - small
http://www.ebay.com/itm/6-GAL-VACUU...349&pid=100011&prg=1005&rk=2&sd=130860754314& - larger

To build one, you'll need a vacuum chamber (there are DIY to build them similar to ebay links, or you can buy a 'bel-art' style desiccator), and this -
(1) 1/4" NPTF tee adapter
(2) 1/4" hose barb x 1/4" NPTM
(1) 1/4" hose barb x 1/4" NPTF (for the pump to hose connection)
(2) 1/4" valves
(1) vacuum gauge
Silicone tape
1/4" pvc/vinyl tubing (2 lengths of 2-3 feet)


NPTF = female NPTM = male connections.

You can save about $60 or so making one, just be sure your connections are sealed well or you'll have to re-tape them all (if you build it).

 

[vertigo0007]

Ive had fjcs, harbor freights (fjc) and mastercools. 2.5, 3 and 6. I didnt see any discernible difference between them when used on a chamber 3 gal or under, other than the 6 obviously pulling down a few seconds faster.

 

[GET MO]

http://www.amazon.com/Glass-Desicca...F8&qid=1362203271&sr=8-13&keywords=Desiccator

what about this? would this and a tube work?

 

[CarefulGrower]

No, it needs a port to attach the hose, can't find one on that one (unless im blind). Needs a "vacuum" desiccator


http://www.amazon.com/Glass-Vacuum-Desiccator-6-150mm/dp/B006ATSULQ/ref=pd_sim_sbs_indust_3

 

[PuertoviejoKL]

You can either buy or build a chamber and adapter.

I was curious what difference does the size in chamber make, 5 G versus more. Does it make a difference in the vacuum power required, or does it just relate to the amount of material you wish to process.

 

[CarefulGrower]

I was curious what difference does the size in chamber make, 5 G versus more. Does it make a difference in the vacuum power required, or does it just relate to the amount of material you wish to process.

A bigger chamber will take longer to reach absolute vacuum. A 3cfm pump will vacuum a 1gal chamber quicker than a 5gal, but both will hit -29.9 (depending on your altitude). The advantage of a 5 gal chamber is a bigger purging area so you can purge larger amounts.

Bigger than a 5 gal chamber isn't much point, in my opinion. Lots of steel beyond 5 gal, it needs to be semi-thick to prevent implosions. And 5 gal has a big bottom (1 oz of bho fits easily, spread thin), and if you're purging more than that consistently, I recommend a vacuum oven, do a couple of racks with 1+oz on each rack. That's commercial thinking though.

 

[Gray Wolf]

What does "cold boil" mean? can you elaborate on this a little bit or send me to a thread that explains all this in detail? I feal like everyone speakin a different language... Hopefully Ill be an expert soon.

I went ahead and got the fjc 3.0 cfm because a friend had a good deal on it, now I need whatever components in order to get ta purgin. do I just need a hose and a suction cup or is it a lot more to it?

Thanks yall for the help. much appreciated!

Water and alcohol boil at lower temperatures in a vacuum, thus the term cold boil.

I used a hose with a 1/4" flare fitting on my vacuum chamber, which conviently fits the 1/4" flare fitting on the pump.

 

[GET MO]

This one looks cool, but it got a black bottom I dont know if its rubber or what, I need one that can be heated up...

http://www.ebay.com/itm/1-5-Gallon-...349&pid=100011&prg=1005&rk=1&sd=130860754314&

 

[CarefulGrower]

"A rubber base is also included but not attached which helps prevent the smooth stainless steel container from sliding around when in use."

Sounds like the rubber doesn't need to be used. A second valve in between the hose barb/tee will help a ton as well.

I'm a fan of the connections on "minivac7"'s chambers, don't know what they are called, but they are easier to use/secure the hose better than just a barb. He doesn't have a 1.5gal one listed right now, here is his 3 gal chamber, with the 2 valves and 'better' connectors - http://www.ebay.com/itm/3-Gallon-Va.../140925088624?pt=BI_Pumps&hash=item20cfca3370

 

[GET MO]

Good lookin out.

that one u jus posted is cool but its also $60 more. I jus got the 99 one. Lookin forward to gettin my vacuum on!

 

[CannabisTHC]

This one looks cool, but it got a black bottom I dont know if its rubber or what, I need one that can be heated up...[/url]

Its not a good idea to heat up a vacuum chamber from the outside, I've read about numerous implosions happening because people thought they could heat their ebay bought dessicators from the outside. There are a few that have managed to be fine but its definitely a risk.

If you want to keep a certain temperature use a ceramic plate that you heat in the oven before placing in the dessicator.

 

[Gray Wolf]

Its not a good idea to heat up a vacuum chamber from the outside, I've read about numerous implosions happening because people thought they could heat their ebay bought dessicators from the outside. There are a few that have managed to be fine but its definitely a risk.

If you want to keep a certain temperature use a ceramic plate that you heat in the oven before placing in the dessicator.

You can also use a thicker lid. Even though a 3/8" may be strong enough for the 14.7psi pressure, it doesn't seem to stand up well to heat and high cyclic fatigue.

 

[GET MO]

damn I already hit the buy button.... so if Im only heating to about 120 degrees its stll a risk with this one ya think?