SPP Machine Begins

[Anthoney]

Yes you can. It is common practice to do so.

Do you have a link to those cheap collet adaptors?
Can't find anything that cheap. Searched Amazon and eBay.

Your machine is a fantastic bit of engineering. Very compact and simple to a very high build standard. I like it.

Really need to fix up a countershaft so I can use my lathe.

Bit catch 22. Would be easier to do if I had a working lathe already.

Until then I'm in the dark ages compared to you (and after also but with a little light to help).

I've started to build using a wheelchair motor and gearbox. Already has speed controller with it. Fitting some kind of collet or chuck is harder for me than for you. The 15mm shaft is tapped M8 to take a wheel on a bolt but either the tapped hole or the bolts I have tried in it are not quite true.

[DAD300]

Anthoney...the "end" of your motor's shaft is taped for an M8 bolt? Make your mandrels from M8 bolts or threaded rod. At the speeds you'll run it a slight imbalance will not keep it from working.

[BigSwede]

Anthoney, I am out of town, forgot my Amazon password. In a day or two, I will give you a link to the ER collet nose adapter I used. It's on Amazon, and they have a thousand different ER chucks, this one was 17 bucks IIRC and is made with a stainless easily workable with regular HSS tooling.

Don't need it, a 1/4" hole drilled in steel with a pair of set screws would work, but it's elegant and allows for gripping diameters from nil up to 3/8" for the -16 series, I believe. So experiments with different bits can be tried.

Update on the machine... It was ready to test, but I wanted to verify the cut senseo and cutter, so I hand fed strands of SPP in there, and unfortunately, every 30th cut or so got pinched between the sense wire and the cutter body, causing the cutter to jam closed. That would of course be disastrous if the machine was running.

I have to go with a photoelectric sensor which I know will work. That has a clear path, and will not jam.

Dad300's idea WILL WORK if designed for in the beginning. In my case, I couldn't simply add it on. Simply put, the SPP strand and entire cutter and machine are DC ground, say 12 V, and the sense probe is insulated/isolated +12VDC. The two touch, 12VDC gets routed into a zero crossing SSR, solenoid closes.

I hope to test with the photoelectric in a couple of days. That too was an Amazon cheapie at $12, and works very well using a single LED as a light source. SPP interrupts beam, relay closes. Works beautifully on the bench.

Links to cheap Amazon goodies to come...

[Anthoney]

Dad300: Yes it is. That might be the best way forward. I can be attracted to elegance for it's own sake but without BigSwede's resources and skillsets to back it up. Just thought mandrels from bolts or allthread might not last too long and was a bit worried about them being off true. Thank's for the reassurance on that one. I don't have a nice precisely controlled furnace to produce exact hardening and tempering. Blow torch and hold it up to see what colour it looks like is the best I can manage. I do suffer from tool envy in the workshop sense of the word. I should probably suppress it and crack on with what I have.

BigSwede: Thanks I will check the links out anyway when you get the time. Regards your jamming, would shortening the wire a little, changing it's angle to the spp stream or replacing it with a thin feeler gauge leaf as you once considered not perhaps prevent it? Or a bit of insulating tape on the side of the cutter body facing the sense wire would prevent it from jamming closed and perhaps it would be self clearing then. KISS.

One question on the design. Everyone who makes one of these seems to take the wire over several pulleys and changes of direction rather than feeding the wire straight at the mandrel. Why? I am assuming it's about smoothing the feed at the point it reaches the mandrel but am not completely sure.

Re: square profile mandrels for Odin's superior angled SPP. The original advice we first received years ago was to use four lobed taps with the thread cutters ground off smooth. Have you tried that?

[DAD300]

I have tried different shapes. One is no harder to make than the other, but the flat screwdriver blade gives a smaller interior void space than the other shapes. Thus more surface to void ratio...

I used running the wire over and around obstacles to add tension and yes it helps relieve any kinks in the wire. Also, if you try to use the original wire spool as a tension device, the wire will get pulled within the spool and tangle. Hope that makes since. Even if the wire is perfectly wound on the spool it will not be after you start to use it. Large welders actually have a motor that spins the spool.

A simple case hardening as you described will be good. I never hardened any of my mandrels and made gallons of SPP from them. In fact I probably accidentally annealed them.

BigSwede's machine would give us all envy...he is a master tool maker. If not by trade, by example.

[cob]

Update on the machine... It was ready to test, but I wanted to verify the cut senseo and cutter, so I hand fed strands of SPP in there, and unfortunately, every 30th cut or so got pinched between the sense wire and the cutter body, causing the cutter to jam closed. That would of course be disastrous if the machine was running.

BigSwede; great build and documentation, as to the intermittent jam have you attempted to moving your sense wire
contact point to the outside edge of the diameter?

[Anthoney]

Thanks Dad300. You were right about the bolts. By the time I have ground one by eye and shortened it the original slight wobble is imperceptible.

Re: Mandrel shape. The lengths you show as examples are all what BS refers to as the helipack type profile, without the offset lobes. I think this makes a difference to the surface area to void ratio for a given shape. We have seen the style Odin and BS favours, that Dogmaster first introduced us to, with the offset lobes.

I'm not fully convinced it is that much better in practice as Odin appears to have moved to a simple closed spring for what he calls his OSPP for larger dia columns, which is not in fact a prismatic packing as such but for which he reports very short heights for his theoretical plates. The offset stuff is pretty though.

I expect to make the helipack style like the ones you show as my wire is half hardened and so not as springy as mig wire but not as soft as fully annealed. It was what I could buy cheaply to be honest and I had not read BS's report on springiness and tension effecting the finished profile when I did. It does make it easier to work with. I decided to buy some 0.5mm, rather than use the 0.8mm welding wire I had in, to properly size it for the two inch column I am using. We will see how that works out given your reports on wire size I also hadn't read at the time. I got busy for a couple of years and left this project on the shelf. Things have moved on and I am catching up slowly.

I fully expect that what I end up with will still be leagues ahead of scrubbies and more than adequate for azeotrope neutral, which is what I am aiming at. Assuming I get it done at all of course.

[DAD300]

I make the lobed design now. It is just a matter of tension and mandrel length. But one design over the other is trading HETP for Through Put. Nothing wrong with either design.

[BigSwede]

Link to the cheap ER-16 collet closer; a whopping $9.

"C16 ER16A 100L Straight Collet Chuck Holder CNC Milling Tool Extension Rod"
http://www.amazon.com/gp/product/B00BXW ... UTF8&psc=1

It's stainless, seems accurate, but accuracy is not required in this application, and cuts with regular HSS tooling. A bargain.

Photoelectric sensor which I am going to hopefully put to work:
"DC 12V Photoelectric Switch Sensor Relay Module 50mmx25mm w 2 Cable"
http://www.amazon.com/gp/product/B00BLZ ... UTF8&psc=1

I've tested the latter with an LED illuminator, and on the bench at least it works very well, triggering the relay after only a loop or two casts a shadow across the sensor. My plan is to machine an aluminum bracket adjustable for height, mount an LED illuminator and the sensor opposite each other across a bore in the bracket, and have the cut nuggets fall out the bottom, perhaps into a tube.

Hi Cob, thank you... The problem I had with the sense wire was simply due to the way I made the cutter. I had to add the sense wire AFTER the cutter was designed, and the cutter mechanism has a hollow, void area above the only place I could put the probe. I tried quite a few variations; most worked great for dozens of cuts, but inevitably, a nugget would hang and the poor solenoid would be buzzing and chattering closed.

If I had planned for it properly from the beginning, it would work. The geometry of my setup is making it hard.

Got the photoelectric rig done, but I've got another trip, so yet again, the acid test, full run, is a few days away. It is what it is!

[Anthoney]

Dad300: So a short mandrel and high tension favours the offset lobes and a longer mandrel and lower tension favours the helipack style? Which is which for throughput and plate hight?

BigSwede: Thanks for the links.$9 wow. I wait with baited breath to see how your new modification works out. Don't really understand why your cutter design makes the contact switch unworkable. If I understand rightly your trip wire is currently at 90deg to the direction of the spp stream; perfect if you want to try and catch a piece now and again. If it was more parallel to the SPP stream but just crossed the path at the right moment then much less likely. Same thing if you use something less rigid than music wire; much less likely to hold cut SPP in place. Combined with an insulating varnish on the back of the cutter body so that the blade is not locked in the closed position it still seems like it could work. But I'm not there and you have your latest refinement to implement now, so we will see how that goes.

[DAD300]

On this chart, data is for a 24mm dia column, but the ratios would stay the same.

I believe the flat lobed version I show above is as close to the BLUE Line as I can get and the Heli-Pak is close to the RED.

The closed Heli-Pak version has better HETP, but easier to flood, but the lobed versions give more reasonable Throughput.

[Anthoney]

Dad300: Thank you for that. It is clearer to me now. I had seen that before but forgotten it in the two years I left all this sat in the corner while doing other things. I have a very sensitive differential pressure sensor I was planning to use to cut the power if flooding looms, so perhaps I will be ok there once it is dialled in. My friend made it for me as an updated version of something from a Russian site. Apparently they use them quite commonly with SPP to prevent flooding. I will try to make my SPP lobed if I can but feel my half hard wire may not be up to it. Time will hopefully tell.

I have a half memory that something like the following style of SPP we were once shown achieves some kind of best of both worlds for HETP and throughput, but that could be faulty memory.

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[BigSwede]

Yes its those shapes I have lusted after since I began the SPP project... And man, I worked hard and did not succeed. The flat blade shape IMO is much more forgiving, seems to be easier to produce at our level of automation. And in my limited experience and intuition, I think the shapes they make are going to work very well if not be at the "pinnacle" of SPP at our 2" to 4" column scale.

There's always time in the future to do bit experiments. I like the idea of ground off taper taps, which is why an ER collet might be a nice thing, it'll allow one to grip a range of diameters.

But to get good experiments it helps to have a machine that can feed wire and cut with some consistency.

@Anthoney... The cutter with its heat treatment is overkill. I did it because I just thoroughly enjoy the process, the metallurgy. I think a much easier way to go would be pneumatics with an off-the-shelf cutter, say a $6 set of cutters that can be replaced with ease by grinding off an arm or bolting to a piece of plate... Blades become nicked or trashed, swap them out.

Electronics is my weak point, the notion of counting loops and sending a "cut" signal to the cutter would be much better, I just don't have the skills to do it.

Cheers, again I am out of town, no work to be done. The photoelectric rig is complete, bench tested, needs to be mounted.

[BigSwede]

Dad300: So a short mandrel and high tension favours the offset lobes and a longer mandrel and lower tension favours the helipack style? Which is which for throughput and plate height?

Added: Anthoney, I was a bit rushed with my reply, I'm editing this, hope you read it.

I am NOT smart on what shapes are the best for what we do; suspect it's application-dependent. My observations are higher tension and stiffer/springier wire, for a given diameter, increase lobe stagger in degrees between lobes. And IIRC higher tension increases loope per inch (more space between loops) up to a point. Wind RPM also changes these parameters a bit.

By running off a foot and putting it on a good lab balance, if you have one, you can get a good idea of how turn spacing is affected. Obviously less mass in a foot equates to greater spacing between turns. These observations are all back there earlier in this thread. Don't know how critical it is, but it's fun to mess with it all.

[/b] If I understand rightly your trip wire is currently at 90deg to the direction of the spp stream; perfect if you want to try and catch a piece now and again. If it was more parallel to the SPP stream but just crossed the path at the right moment then much less likely. Same thing if you use something less rigid than music wire; much less likely to hold cut SPP in place. Combined with an insulating varnish on the back of the cutter body so that the blade is not locked in the closed position it still seems like it could work. But I'm not there and you have your latest refinement to implement now, so we will see how that goes.

Added: You got me thinking... before I take things apart and add this photoelectric gizmo, I'm going to try a sense wire parallel to the SPP path, rather than perpendicular. This is something obvious, should have tried it earlier. TY, hope it works.

[Anthoney]

Well I think the four lobed taper tap may be the path to that particular profile. So we were indicated when dogmaster first brought spp to our attention. Worth a try.

You and DAD300 are right though; the flat mandrel is the most forgiving and will still produce excellent spp that beats everything except even better spp. So I will make that first and try to get something working before obsessing about improving it.

I have some tool steel blades in the tat pile so I might try something with them for cutters.

You already have the encoder wheel for loop counting. Put it back with your new Photoelectric beam and you have the sensor side of your loop counter sorted. Just need a variable pulse counter with auto reset after each cut action after that. You could go complex and learn to program an Arduino; not the cheapest option but supposedly easy to learn to program for anyone with a bit of motivation. A dedicated circuit would be very cheap to build. I'll ask my mate for some pointers and see what he says. Depends how he feels and what he has on with his own projects.

I still believe a man of your skills can make the sense wire work. Successive approximation is normal in experimental design. That is preferably to fancy electronics really. Good luck with that.

[Anthoney]

Had a word with my mate. He says it is only a five minute job to write an Arduino program to count pulses and cut. He points out that the encoder disc was probably on the motor shaft not the gearbox output so there will be more revolutions to count than simply the number of turns you want in each piece.

Still easy enough to do and if you can't resist going that way and find programming the Arduino baffles you then he will write it for you and I'll email it to you. He doesn't think it is worth trying to do it with a simple pulse counter because of the high number of pulses you will be counting off the motor shaft. They are generally limited to smaller numbers.

I still believe the sense wire is the better solution and that you can make it work. KISS.

Based on the numbers you and Dad provided I have made a mandrel that is approx 4mm at the base, 2mm at the tip, 5mm long and 1mm thick. It made a bit if helipack just rotating the motor shaft with my fingers and feeding it in by hand. Side by side winds which pushed it off the end ok. I had to use a six inch, half round file to finish it off. I was too imprecise with just the bench grinder. Case hardened it in oil because I like the blue colour it goes when you do that. Ground and filed a locknut in place for backing as I don't have any concave washers. Fingers crossed.

I'm using mahogany and brass for the feed elements as they are out of my scrap box. No bearings and as yet no springs other than one on the spool. I want the extra drag as I am concerned with the effect of too much tension on the spool as Dad warns there could be danger of tangling. I do have a system similar to yours on the spool but want to try not using it at first.

Anyway sorry to be hijacking your thread a bit. When I get mine winding spp under power I'll start a thread of my own.

[BigSwede]

Anthoney, you aren't jacking anything, as far as I'm concerned, this thread is about home made SPP, by whatever means. Your input is not only excellent, it's very welcomed, and saved me a lot of work. Feel free to post pics here, or on your own thread. I'd love to see what you have going.

This is going to be a long post, but I want guys to avoid pitfalls that I fell into.

Summary - after jacking around with photosense circuits, inductive sensors, this-and-that sensor, I went back to the basic touch sensor. TOTAL FREAKING SUCCESS! The machine is running beautifully. I had some hiccups, with both sensing and ultimately SPP strand feed to the cutter, but she's running like a well-oiled machine, which I guess she is.

Here's what went down.

First off, after a LOT of thought, my conclusion is there are only a handful of ways to make auto cut sensing work well. They are:

1) count loops. Need a microprocessor, maybe a hall device, quite a bit of electronics knowledge. Bulletproof, if done right.

2) Timer. Also bulletproof, but the timer must be easily changeable for RPM, and I've found that I'm varying RPM all the time. It is almost critically needed to start the feed. PWM and a DC motor works great.

3) Touch Sense. Not quite bulletproof, but by far the simplest. Got to have an accurate, smooth feed, and above all, the path from the cut to the bin must be wide open. These things spring about and can leap into crevices and jam up, causing feed issues and forcing the cutter closed.

The issue with any proximity sensing is that electronics are too fast. With a reflective photosense, what happens is that as the nugget falls, the shiny loops can trigger a number of cut commands. For a 10mm long nugget, in the time it falls, it might signal a half dozen cuts as the light rays flash, and electronics are fast enough to execute them all. You could set it up so that the CUT command enables a one-shot timer, but now the complexity is going way up. I think the above three are really the only true options for the average home builder.

Here's what I did:

Carved a bracket out of aluminum, bored through to drop the cut SPP. Took a piece of 1/8" phenolic board, and mated that with some copper. The copper above is a loop cut and formed from a 1/2" OD pipe, soldered to a flattened wire.

The front half of the loop was cut off, the rest epoxied to the phenolic. Note that I can move the hemi-loop into the path of the SPP, then clamp down with the set screws. Since the SPP strand is spinning, it wobbles all over, and contact is guaranteed. The hard part - the path of the falling nugget must be wide open and clear, or it will jam.

What the mod looks like before attachment. The Cu pipe moves the cut SPP into a bin. You can add plastic piping onto that, let it all feed into a bucket.

Mounted in place. Note the LED and the CUTTER ENABLE switch. The latter simply removes the solenoid from the circuit, and the LED is in paralle with the normal CUT command, so I can test without losing fingers. This is a MUST HAVE for any machine. Got to be able to test without cutting.

I began running this morning. After tweaking the sense a bit, I had solid performance. Thought I was done, but then I had two instances of the SPP strand balling up before it could reach the copper feed tube. I replaced the copper tube with a PTFE tube; polyurethane would be fine. It still makes electrical contact at the cutter body for sense purposes.

With the PTFE tube installed, she runs great! I'm tickled right now, after a lot of work, I think I have a solid machine that will run a long, long time and make nice SPP. After 2 hours, the motor was slightly warm, solenoid cool, SSR cool, PWM cool. Everything FINALLY came together!

I shot some video. If I can figure out how to get it up anonymously, I'd love to share it.

And anyone, please feel free to dive in with thoughts. I'd still be farting with photo-sensing if Anthoney hadn't kicked my rear end. Anthoney, I'd love to see your own build thread when you get there.

Next up, mass production for my own rig, then I'd like to play with ground taps and the like to improve the profile.

[BigSwede]

BTW, Anthoney, I appreciate the offer you made re: the programming. Believe it or not, 10 years ago, I considered myself to be a pretty good programmer of the PIC series of uProcessor chips, and this whole time, I was thinking of just how easy it'd be if I could get the cobwebs from my brain, drag out my PIC stuff, and have at it, but I've forgotten 95% of it, and I don't even know if my PIC hardware still works.

Unfortunately, this motor no longer has an encoder, but a hall chip and a magnet on the collet nut would serve even better. But touch sensing is simple so long as it is planned for from the beginning when engineering the cutter. I didn't do this, and it cost me a lot of time. And the way it is set up, unfortunately, the shortest cut I can do is about 8mm. It'll still work!

Anyone have ideas on anonymous video? Can YouTube do this?

Wanted to add: this spring-loaded gadget works very well. As the wire unspools, you can literally hear popping and pinging, there's piano-like tension on the wire, and the spring-loaded pulley tracks left and right, absorbing and smoothing things out significantly. I don't know how critical this is, but it makes me feel better! I think it makes more consistent strands.

[Anthoney]

Thank you for the reassurance and encouragement, I appreciate that.

Wow, and I thought you were just going to rotate the sense wire 85deg!

Enviable work as usual. Glad it is working now.

Must be nice to have a working lathe, a milling machine and plenty of stock materials lying around. Mine is basically made out of junk by comparison, well somewhat literally as well. More of a kinetic sculpture than precision engineering.

I will still post some pics after I get it somewhat operational.

The only reservation I have with your design is the how the spool of wire will stand up to mass production with the tension directly on it. Dad has pointe out that this can cause problems on mig welding machines and they take steps to avoid it.

You still have the brass clamp as a back up source of drag though. So all should be well one way or another.

Why is your min cut 8mm? Can you work on that?

A Pic chip was may mates first suggestion but I didn't realise you had programmed in the past so dismissed it in favour of the less demanding Arduino.

You can anonymize your browsing and uploading by using the TOR browser. Well worth downloading. Even your ISP won't know what you are doing.

[Anthoney]

If you had persevered with a photoelectric sensor I think a beam breaker that only triggers when the sensor is sufficiently shaded would have been the way forward. Less trigger happy.
What you have done is better though.

[DAD300]

Beautiful...but you're teasing us! Show us some SPP.

As to using the spool as the tension device. My setup pulls the wire off the 30 lb spool, but the spool is not the tension device. It rubs on the stand only to keep it from free wheeling wire onto the floor.

From the spool to the lathe, the wire runs over two fixed posts, wraps around a piece of PEX pipe. Between the fixed posts is a perpendicular spring I adjust for tension. Again very unsophisticated, but infinitely variable.

I had spool issues. One of the 30lb spools I bought arrived with broken edges and the wire did not come off the spool evenly.

[Bob Loblaw]

Anyone have ideas on anonymous video? Can YouTube do this?

Try vidd.me

[BigSwede]

Wow, and I thought you were just going to rotate the sense wire 85deg!

When I went back to touch sensing, I wanted something that would work forever, be adjustable, repeatable, for different bits and different SPP dimensions. With this thing, I can measure the distance of the phenolic insert and note this in a log so when I change bits, I can repeat.

Plan today is to add a 40 turn-per-inch adjustment screw so I can move it in and out without dismounting the whole bracket. Then it'll be "OK Bit 3 mounted, need 0.115" or 4.6 turns of the screw."

Gonna add a big red mushroom EMERGENCY STOP switch too, could have used it during testing more than once.

The only reservation I have with your design is the how the spool of wire will stand up to mass production with the tension directly on it. Dad has pointe out that this can cause problems on mig welding machines and they take steps to avoid it.

You still have the brass clamp as a back up source of drag though. So all should be well one way or another.

I have a sacrificial aluminum disk between the machine and the spool. I can't see that disk wearing away even after hundreds of spools. I tried it both ways, and with a screw-down type of clamp for tensioning, it goes from too loose, to locked, in 1/10th of a turn. At least it did with my mechanisms.

There are other, better ways to tension; Dad's pic once again impresses me with the simplicity and elegance of how he did it. Love the spring device.

Why is your min cut 8mm? Can you work on that?

The guillotine blade travels in a brass bracket. The distance between the blade, where the cut takes place, and the bottom of the bracket, is about 4 to 5 mm. I can't get any sort of sensor above the plane of the bracket's lower surface... does this make sense?

Beautiful...but you're teasing us! Show us some SPP.

TY DAD300, I've appreciated your suggestions and encouragement from the beginning. You have an excellent engineering mind IMO in that you find simple, effective solutions. I usually pursue fiddly complexity. I'm hopeful that my complex VM/LM head will perform... I think it will, and I need to churn out some SPP to use with her.

How tall a column should I load? I'll take some pics today of the #4 SPP that's accumulating, get a vid up too, somewhere.

[Scribbler]

Okay, hang on a sec... I'm confused! Is this entire thread about finding a better way to make the packing that gets shoved up reflux columns? This is usually done with copper scrubbers or ceramic rashig rings?

A) is there actually THAT much improvement to be gained by enhancing the packing material to make this worthwhile? Or is this more of a "I'm doing it because I can!" Type thing?

B) why not use copper wire instead of stainless steel?

C) this is all pretty awesome stuff! I don't even DO reflux distilling and I am absolutely enthralled by what you folks are doing here!!

[Scribbler]

D) bigswede: above, you mentioned that you bored through (or bored out) a piece of material... In machinist lingo, is boring the same as drilling? Or does the term 'bore' have an additional definition?

[BigSwede]

Okay, hang on a sec... I'm confused! Is this entire thread about finding a better way to make the packing that gets shoved up reflux columns? This is usually done with copper scrubbers or ceramic rashig rings?

A) is there actually THAT much improvement to be gained by enhancing the packing material to make this worthwhile? Or is this more of a "I'm doing it because I can!" Type thing?

Hell yes, and yes!

B) why not use copper wire instead of stainless steel?

Copper does not have the inherent spring necessary to "open and expand" when it exits the bit. If the wire used is too soft, you get a strand identical to the upper one in this pic. The wire used in the upper strand was dead soft SS aircraft safety tie wire. The bottom strand is SS MIG welding wire. Both came off the bit pictured.

The upper "SPP" (isn't true SPP) would actually probably work to a certain extent. That's my noob guess.

That said, I HAVE seen pics of copper SPP. No idea how they did it.

C) this is all pretty awesome stuff! I don't even DO reflux distilling and I am absolutely enthralled by what you folks are doing here!!

Scribbler, I know you well enough even though we haven't met, you'll be playing with this stuff soon enough, as well as various reflux rigs, flutes, etc. You get as much out of fabrication as I do!

Added a red EMER STOP button today, playing with the machine, she's running well!

[DAD300]

Scribbler...it takes about 5" of SS Scrubbies to make a plate, HETP, and approx 1" of SPP. So in a 48" column Scrubbies make approx 11 plates and SPP makes approx 48! So you could make the column 12" and have the same plates a 48" scrubbie packed column would have.

I have a 3" x 30" column that makes azeo at 1:1 reflux at 4-5 liters an hour from a 10-12% wash.

Copper SPP will crush at relatively short heights under it's own weight. It will wear/tarnish and require more advanced cleaning, while the Stainless is about as permanent as possible and I run water through the top to clean it occasionally.

Imagine replacing the thumper on a pot still with only 2" SPP reflux column above the pot! That would get you into the 80-84% range from a 10% wash or mash.

The closed design is more accurately called Heli-Pak than SPP. It is more power efficient, and will get you a great HETP, but much much lower Throughput.

BS...I loved your original tension device. Line the inside of your drag device with a harder or slicker material and it should be more adjustable. That's how I ended up with the PEX. It is slick enough it survives without heating up or cutting.

[manu de hanoi]

guys, this is a construction thread, isnt there a SPP all purpose, brainstorming, Q&A thread somewhere else ? If not can you create one DAD ? We already have 3 pages of information that does not belong here.

[BigSwede]

Manu... Technically, it's my construction thread, and I welcome any and all comments and discussion, but it's up to the moderators. If they want to delete or move or conglomerate, it's their call, certainly.

DAD300, I guess I didn't try hard enough with the original tensioning rig... anyway, I'm not going to mess too much more with it. Time to put it to work to make packing goodness for my poor VM/LM column which has been put aside temporarily.

Video is up! Six minutes. Long winded, like my posts. You can fast forward to where she runs if you don't want to hear me yakking.

http://youtu.be/-RkQMxyGbvQ

[Scribbler]

Bigswede: yes, I feel the temptation coming on... I will put 'reflux stuff' on my list... After plates & dephlegs...

The way dad300 describes it (replacing a thumper with a packed column) there seem to be practical applications of this sort of thing in flavored whiskeys and brandys? (I'm just NOT a neutral/vodka fan, so I've never really read too intensely on the matter!)

HETP: heat energy transfer paradigm?