stepper motor / PC control of emulsion making

[Kirk Keyes]

Your excuse for not sharing information that you have acquired is that you were told not to share it freely?

If someone tells me something in confidence, then I try my best to maintain that confidentiality. I know some things that I've worked on through my employment that I am required to not discuss publicly. And I maintain those confidentialities.

But anything I've figured out or learned for myself, I'm more than happy to share with you or anyone else.

 

[Ray Rogers]

Ray;

The conflict in numbers of the dyes was resolved in a series of posts by myself and Bill Winkler. He now has the dye. My data sheet, as I posted on APUG has BOTH numbers!
PE

Hummm, yes I recall! But you claimed to be just as confused as I was, because unless I missed something, the last I heard you say was something to the effect of either the nomenclature was changed or they made a mistake somehow; You ended with "Your guess is as good as mine."

So if there were no further relavent data given, since we have neither the structure nor the CAS, it still sounds pretty unresolved to me.

If one is willing to buy from them,
I guess you could just let them figure it out.
But what if there are actually two different products?
We know you got a product with 2 names on it...
But which one did you actually ask for, initally?

Anyway, this situation is not your fault. I know that.

The week of the conference, neither of us were able to take the time to go to my home, so I brought sample pictures to the meeting to show you. I guess you have forgotten. I was at the meeting from dawn till dusk and took a short course. You spent time at GEH. I guess you have forgotten all of this.
PE

No. I did not forget what happened.
It is pretty much as you say, except for the implication that I would have turned down an invitation! I stayed in Rochester quite a few days after the conference BTW.

I am sure that your pump works just fine and so do your emulsions. May we see a sample print or negative scan of one of your emulsions? No formula, no secret data, just a scan?

Thanks.

PE

I can think of no reason to say no.

 

[Kirk Keyes]

[...] so I will end this arguably invasive nonsense here and now by saying that your capacity is roughly the same as mine.

OK, Ray. That's fine.

I've never used a syringe pump, and I'm interested in getting one. That's why I was asking about model numbers or manufacturer. If I know what you use, then I can compare with other items I see for sale. That's all.

Other than having seen PE's Model 1 in use, and my own Model 1, so I was wondering how you've been applying your's and how you like it?

What advantages do you see with a syringe pump over a peristaltic pump?

Have you tried using preloaded syringes with different concentrations or volumes or do you simply use it with one solution? I can see where it would be nice to have a couple syringes filled and then you can add multiples of reagents over time, just not all at the same time.

Have you figured out the dead volume of your syringe and lines? Do you do anything to over come that issue?

Can you swap syringes pretty easily - I assume they Luer-Lock in?

One advantage of the peristaltic pump is you can pump out the lines to deliver the full volume of reagent that you measured out. And you can switch solutions serially by moving the pickup tube from one container to the next. And you can even pump more than one liquid at a time, if you have a peristaltic pump with multiple pump heads, and at different rates if you can get tubing of different internal diameters.

So I'm curious to see what you think of these approaches, since you have a syringe pump.

THanks for helping Ray.

 

[totalamateur]

I'm curious about the capabilities of syringe pumps as well,

A lethal dose of coffee is 80-100 cups in an hour, so am I to presume that your syringe pump can do anywhere from 4 mL per minute to 400mL per minute, and if so, how big is the syringe? 24L per hour for several hours would be a pretty huge syringe pump.

 

[Photo Engineer]

Ray;

Bill Winkler resolved the issue in his posts and ordered the dye. The company refused to give anyone structural data. What can I say?

We said goodbye at the end of the conference, you said you would send me copies of the pictures you took (which I don't have yet 2 years later) and you told me you were rushing off to Texas to visit relatives. That was the last I heard from you in person. I was dashing around for the full week to all of the events I could cover.

Kirk;

The big problem with syringes is as you mention, the inability to pump out the lines. It cannot be solved except by draconian measures or by knowing the line volume precisely. The big problem with peristaltic pumps is the pulsation of the flow, which becomes greater as flow rate decreases. This problem can be rather easily solved.

A secondary problem with syringes is that unless you have a good "lock" on the tubing, at high flow rates you can blow the tubing off the connector as the syringe does not use a Luer lock for the tubing, only for special connectors, and these present additional problems of availability and throughput. You need "O" clamps with incredibly tiny diameter and which form circular (not oval) clamps when tightened.

And here, I bet you thought I was sitting on my thumbs. I have a huge set of boxes filled with all types of fittings to try to solve these and other problems, the list of which would be quite long. They will be in the book and the DVD, and also will be described in my Emulsion Making and Coating Workshop II if I ever get around to giving such a beast. It is under development along with the book.

PE

 

[Ray Rogers]

If someone tells me something in confidence, then I try my best to maintain that confidentiality. I know some things that I've worked on through my employment that I am required to not discuss publicly. And I maintain those confidentialities.

Of course. That is second nature for a man of integrity.

But anything I've figured out or learned for myself, I'm more than happy to share with you or anyone else.

I am sure you mean what you say.
But isn't it relative, and only trully valid when sharing poses no real nor imagined threats?

Peace

 

[Kirk Keyes]

The big problem with syringes is as you mention, the inability to pump out the lines. It cannot be solved except by draconian measures or by knowing the line volume precisely. The big problem with peristaltic pumps is the pulsation of the flow, which becomes greater as flow rate decreases. This problem can be rather easily solved.

Well, to pump the lines out, if you can mount the syringe pump so that the plunger end is up, then you can put some air into the syringe and hope it pushes the last bit of air out. This will probably put a few bubbles into whatever you are pumping it into.

You mentioned the problem with peristaltic pumps is pulsation. Increasing backpressure into the system by pumping into small diameter tubing can help. And prehaps more important, use a pump that has as many rollers as you can find. The pumps I've use in labs and the one I bought have 8 rollers, and they will do a much better job than any 2 roller pump. In fact, I do not recommend 2 roller pumps when flow rate is important. If all you are doing is moving liquid from one place to the next, they can be great, but not if you want some sort of control on flow rate and its variation.

 

[Kirk Keyes]

I am sure you mean what you say.
But isn't it relative, and only trully valid when sharing poses no real nor imagined threats?

I'm having trouble imagining what you mean by imagined threats...

 

[Kirk Keyes]

A secondary problem with syringes is that unless you have a good "lock" on the tubing, at high flow rates you can blow the tubing off the connector as the syringe does not use a Luer lock for the tubing, only for special connectors, and these present additional problems of availability and throughput. You need "O" clamps with incredibly tiny diameter and which form circular (not oval) clamps when tightened.

For higher pressure stuff, peristaltic pumps are probably not the best answer... And plumbing with fittings like Swagelok for metal, and they have other systems for flexible tubing.

But yeah, high pressure stuff can be an issue. But in general, unless you are donig ultrafiltration like you have been working with, one really doesn't need that much pressure for general emulsion making pumping.

 

[Photo Engineer]

Kirk;

At high flow rates, pressure can be high. If you look at the posts of pictures, you can see my fittings.

As for syringe pumps, if you mount them upright with a head of air, this can work but also can cause a leak to develop before the pumping action starts.

Of course, I have solved most of these, and it appears that you have too. When you get right down to it, if you use the right pump, you do not need a syringe.

PE

 

[Neanderman]

Are you a den den den... guy with Drill?

No, but I kept one in business for a few years, catching up with some bad dental care during college. :-(

I might be able to make a small batch of emulsion with the silver that's in my mouth...

Ed

 

[Kirk Keyes]

I might be able to make a small batch of emulsion with the silver that's in my mouth...

You'll need to boil off the mercury first so it doesn't contaminate the silver. (I know it was ajoke, but don't try to separate the silver and mercury from almagam. Mercury vapor is not that good for you.)

 

[Neanderman]

You'll need to boil off the mercury first so it doesn't contaminate the silver. (I know it was ajoke, but don't try to separate the silver and mercury from almagam. Mercury vapor is not that good for you.)

Not to worry! I'm steering away from Dags, too.

I also wear felt hats and know all about the "mad hatter" syndrome.

Ed