You’d be shocked but yea that’s how much they cost. I can get you one with a custom drive for the same price. It’s just how much they cost. You don’t fuck around when it comes to quality. I got them with trace line heat plumbing built in with ports.
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if you’re too poor for a gear pump keep using flasks
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Well that’s pretty nifty
So, there’s something wrong with engineering something that could potentially be on par with the more expensive version for cheaper?
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@spdking you really liked @downtheterphole shitty comment?
Just wow. 
Ya know… a lot of people blow you shit. Watched people slag on ya for things you’ve said.
Never liked a comment that was derogatory towards you. I don’t roll like that.
Thought it was a reasonable conversation on learning about these pumps then terphole had to jump in and be petty child with his snide comment and you liked it.
Class act, buddy…
Class act.
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I don’t have any experience with a peristaltic on an SPD, but tried a few experiments with a peristaltic on the solvent flask of a rotovap under vacuum. What I found was that a 3 roller peristaltic allowed a lot of backwards flow/reversion to happen, moving liquid back towards the vacuum source, which slowed output considerably from what I saw from that same pump when it was pumping liquid from even pressure zones. I suspect to get descent flow characteristics you would need at least a 6 or 8+ roller pump in either application
With thicker tubing you lose some amount of flow, but it’s not like an SPD output pump needs to move a ton of liquid volume in a short timespan. For what I was trying to do to empty a team of 6x 50L rotos, a 6+ roller peristaltic that used 1" or 1.5" tubing was cost prohibitive, but smaller units with a higher roller count should be more affordable, downside is that you may run into a problem where the motor/gearbox affixed to it isn’t sufficient to pump against vacuum at 100% duty cycle, and using a VFD to slow down a motor’s speed also typically slows its cooling fan which means more heat which isn’t good for the drive motor’s longevity.
I think Elliot is completely wrong claiming that the low speed that peristaltic pumps operate at is the reason that they can’t maintain operation under vacuum, it’s all about tolerance and whether the pump is completely closing the hose opening or not. If you have to crank the RPMs way up to maintain vac levels I can only think you’re using the wrong tool for the job.
I was using 3/8" silicone brewery tubing in my pump and didn’t have problems with it collapsing under vac. I would expect that the larger diameter you go, the less selection and more $$$ you’re going to have to pay to get a thicker walled tubing that’s suitable for what you want to do.
I’m afraid I don’t have any recommendations for brands to try this out, what you want is something that’s really overbuilt for your application, both from a motor HP and gear reduction standpoint as well as a rigidity/frame/industrial usage standpoint.
I do agree that $7k for a relatively tiny gear pump with a high NPSHR value seems insane.
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Just so we are clear. There’s a shiny asshole side to me. Sometimes I like things I feel are sarcastic.
The wasted money and failed attempts to create the same effect from a proper pump made me realize without any issues o should just use a pump. O mean I had some sucess but those pumps I couldn’t sign off on bc there was some short coming somewhere. Instead it is a bit obvious that if you don’t Wana use gear pumps maybe glass flasks is best.
I’m not insulting people. I just saw that comment with snarky sarcasm. You’ll find people can like things and still be normal people.
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I’m new to all this (not SPD, just the pumps). I thought it would be a cool concept (less clean up, less glass to break, straight to the liter jars).
I get what you’re saying and after researching more and seeing the size pumps available, I believe it can be done. Just matching pump size reduction (for torque) and a hose thin enough to “squish” to keep a seal. Running a second condensor prior to the pump to thin out the oil and add heat to the tubing that should allow it to be more flexible.
I’ve never been one to pay the “green tax” on equipment that was used decades before. Just a few tweaks here and there and just about anything should be adaptable.
I’ve gotta line on a few pumps that have the reduction drives, high tension sprinted rollers, variable rpms, and I’ll be checking out tubing this weekend.
I’m pretty sure it would work with the right combos
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I didn’t think he was talkin shit. Lol (maybe I’m too chill)
I’m too poor for a gear pump. And I don’t take offense…
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So is it proper business etiquette to like when someone makes a feeble attempt at belittling a potential customer? You offer to sell me a custom gear pump with all the bells and whistles then that happens.
That’s what I was getting at.
And we know buying something already set to run is more expensive then purchasing from the manufacturer direct and building yourself.
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You can disagree with me. That’s okay. Plain and simple i did this and it does have issues with back feeding molecules. The roller action is still not as effective at forward pressure with vacuum. High vacuum. I also seemed to have issues with rotos at about the 30-50 min mark with those pumps.
Gear pumps move very very fast. Internally insane speeds. The movement is usually enough to prevent those issues. And to be fair I’ve been machining them for mods, I blow through 650-750 index holders and index cutters like no other. One after the other. The stainless is heat treated vacuum super dense stainless. The controllers aren’t cheap. Gear boxes either. The best ones are from over seas and that has its own uk importing times and premiums.
.you can always find a 1k gear pump. No hurt feels.
I’m not belittling you. You are taking offence to basically nothing. I never said anything mean to you. I just liked someone sarcastic comment. You’re taking this the wrong way.
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I just feel if you have nothing to contribute to the conversation, why bother…
You want that shit, go troll on Reddit.
I don’t take offense to things that aren’t true. I think envy is something that just strives to make you work harder. The latter is what put me where I am today.
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Not knowing how to select proper inserts for what you’re cutting or correctly set your speeds and feeds when machining is a real weird flex but ok
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I never said you belittled me.
You read what I said wrong.
Maybe we conduct business differently. I come from a background of lifting people up, helping who I can, and leaving this world for my kids a better place then when I arrived here.
You’ve given good advice with any Interaction I’ve had with you. You know your shit. No doubt.
But you, more then probably anyone on here, know what it’s like to ask questions and then catch snarky and unproductive comments for no reason.
Why it happens? Jealousy? Envy? Who knows. But it’s the equivalent of two adults having a conversation and your kid keeps interrupting by tugging your pant leg. Then when you finally ask them what they need/want, they respond with “hi”, then runaway.
Just breaks the flow of productiveness in a conversation.
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How was this a shitty comment? Seems like common sense. If you can’t afford the right tool for the job (unfortunately in this case that’s 7k) then continue to use flasks. No hurt feelings…
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Trust me I got the best and hardest materials.to work with. I’m not buying harbor freight tooling. Gear pumps are literally that hard of a material.
You’re fabricating outrage because I likes someone’s sarcastic comment. Then you’re looking too deep into it trying to cause some kind of hurt feels and narrative I never ever gave off…not sure what you’re getting at here but you can get over it now. I wasn’t insulting you or pushing you down. Stop fabricating shit like this. I simply liked a sarcastic comment. Are you going to berate everyone on here who like nasty or sarcastic commentary???
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What value did it add to the conversation?
That’s all I was getting at. I’ve been married almost 20 years. Trust me when I say I have thick skin.
Necessity is the mother of all invention.