Home Distiller

There's no doubt creating the multi-holed endplate used in a shotgun condenser or dephlagmator is not a trivial task, and soldering the beast is worse, because other components tend to come loose while heating to solder another portion of the subassembly.

I tried hard to figure out how to post more than one picture using the "upload attachment" feature. I know I can link to images, but I'd rather not do that, for reasons of extreme paranoia. So It might end up being one pic per post.

Theory/philosophy - We want these end plates to be self-supporting, which means a formed cup shape that is a nice tight fit into our pretty copper pipe. If the pipe ID is 2", then we want to start with a copper disk that is greater than 2", say 2.250", and form it into the correct cupped shape. This can be done in a couple of ways... spinning, or by stamping/forming the disk into the desired shape.

Unfortunately, what I am going to describe requires a lathe, or some imaginative workholding with a drill press or similar, but maybe it will give someone some ideas.

If your copper tube is 2" ID, and your sheet stock is 0.025" thick, then we must form it with a mandrel that is 2.000" - 0.050" in diameter, with a more realistic diameter of 1.930" rather than 1.950". This provides for some slop and spring in assembly. Bear with me!

I started with a copper disk of 2.300" or so, cut from 0.025" copper sheet. In my first attempt, I drilled all of the holes for the 1/2" OD tubes that would form the shotgun condenser. This was a mistake, as the forming operation stretches the copper disk, and the round holes become elliptical! Not good. Since my mandrel requires at least the central hole, I drilled another one 1/2" and tried again. BTW, this hole was drilled with a 1/2" Forstner wood working bit, which cuts beautiful, clean holes in copper without grabbing or digging in.

I'm not sure why, but the picture looks like brass - it's pure Cu sheet.

This was mounted on a mandrel I turned from aluminum. The edge was given a tight radius, and the OD of the mandrel was 1.930". It is important that the copper disk be securely clamped to the mandrel, and this was accomplished with a 5/16 hex head cap screw and an aluminum disk with a short 1/2" rim (not shown) that fits into the 1/2" hole in the copper disk.

Mounted in a lathe, an ancient Hardinge HLV, the copper end cap was spun into a slight funnel shape. Before this, I heated it barely dull red to anneal. Copper work hardens VERY fast, and after one anneal session - I quenched in water - you get one shot at a forming/shaping before it hardens and resists further forming. It's something that you can definitely feel. I used a delrin rod shaped into a hemisphere to form the partial cup.

Here's the simple part... a short section of 2" ID PVC schedule 80 pipe is all that is needed to form it into a nice cupped shape that will fit into a 2" copper pipe.

I used a small hydraulic press, but I could tell from the forces - very low - that the mandrel + copper disk could easily be pressed through the section of PVC with a mallet or similar. It slid right through, no problems, and formed a nice skirt.

Before that final push through the PVC, I gave the disk one more anneal session. It took about three anneal sessions with a propane torch to get the job done.

It entered a 2" ID copper pipe with a bit of pressure. All that remains is to drill the remainder of the holes needed to create an endplate for a shotgun condenser or dephlagmator. One trick would be to center pop or at least mark the locations for these holes. As I mentioned earlier, if these additional holes are pre-drilled into the copper sheet used for the end plate, they become "smeared" into ovals due to the pressures of the process.

This sort of disk will hold itself VERY firmly into your copper pipe so that when you solder the individual smaller tubes, it'll all hold together and not move a millimeter.

I understand that this requires tooling that most guys don't have, but the forms themselves can be made of wood or other impromptu materials, sized for the pipe diameter desired.

Very nice...making tooling is a pain, but now you have it forever.

Nice job mate, and good tutorial, wish I had the tools you do!. I'm a but confused though, does the done shape hold it in the pipe better?. Once you've done one shot gun end plate it's like riding a bike, I always now, solder the inner tubes into the plate, then slide the section into the pipe, and solder the plate in from outside, never had a problem since doing it that way!.

this is taking it to a whole new level, some pro work there.

bellybuster wrote:this is taking it to a whole new level, some pro work there.

TY... I did think "why post" because few guys have a lathe, but this really could be done with a wooden dowel and a short PVC pipe section pretty easily. The mandrel diameter isn't all that critical. When it goes into the PVC pipe, it's the PVC itself that forms the nice skirt. And the initial rolling over I did in my lathe could be done by hand very easily.

I know there are 1/2 dozen ways to do this. I like the idea of the end plates being very firm in the tube... it not only will seal well with just the tiniest bit of solder, it'll hold firm for all the fiddly small tube soldering.

I practiced a bit with the 1/2" OD tube I'm going to use for these, and it was really easy to form a rim such that the formed rim will sit flush with the end cap surface. This was done using a $3 flare tool to get the end of the tube slightly expanded, and then with the tube held securely, the flare was rolled over (after annealing) into a sweet little rim.

My plan is to solder all these vertically, and the other end, which has all of the tubes in their normal 1/2" OD, no rim, will simply poke slightly through the opposite end cap for a nice solder fillet.

Anyway, I was very happy with how easy it was to form these using the PVC pipe section.

Nice work. I got the same profile on my end plates when I stamped them out. With a press.

One thing to remember. The one you show soldered in. Would be ok for the lower plate of a shotgun. But you should flip it over for the top plate. To create a bowl. That will direct any liquids into the center tube. So it can drain off.

When I built my shotgun. I made both ends concaved in. It has flanges on both ends. So I wanted to be able to install it in either direction. If I wanted to.

Good call. I drilled out the remaining holes, and they came out pretty nice. Got four on hand now, 2 for the current project, and two for the future.

Once the tooling and process was set up, these things are not hard to make, maybe 15 minutes per. I figured "why not make some spares?"
All that remains are the small inner tubes, and the fittings for the 2" outer. My plan is a sankey at the bottom at a minimum. That's going to take up an inch of outer Cu tube because the ferrules I bought are 2" OD and go inside.

I think I figured out how to do more than one attachment per post. Testing...
Nice, it worked. The setup to drill the other holes in the end cap. This pic shows the Forstner-style bit that does well in copper without digging in horribly and pulling the copper upwards, to whip around dangerously. I've also confirmed it cuts a nice hole in heavy tube as well. A little cutting oil helps. These work much better than standard twist drills.

I like step drill bits. I've had better luck with them then regular ones.

+1 on the step bits. That is there purpose sheet metal.

AC

<vent>
I vote we don't allow posting by people with lathes and other advanced machinery in any website area except one specifically segregated for them.

Also, we cannot let their posts to be indexed and visible by the site's majority of mere mortals as it causes unnecessary envy, consternation, and, ultimately, generalized feelings of inadequacy.

</vent>

It takes a special kind of dork or gear head to treasure his machine tools more than his vehicles, or just about any other sort of material possession. The thing about machine tools, what makes them so appealing to me - they are the foundation for just about everything... can MAKE just about anything. Or can make the tool or fixture to do the job.

You're doing a fine job at what you're making Swede. I have to admire your craftsmsmanship.

Prairiepiss wrote:Nice work. I got the same profile on my end plates when I stamped them out. With a press.

One thing to remember. The one you show soldered in. Would be ok for the lower plate of a shotgun. But you should flip it over for the top plate. To create a bowl. That will direct any liquids into the center tube. So it can drain off.

When I built my shotgun. I made both ends concaved in. It has flanges on both ends. So I wanted to be able to install it in either direction. If I wanted to.

Prairie: what did you use for forms on your press? I am totally in love with this build, but I don't have a lathe... Would it work to use an actual piece of 2" pipe and a 1 7/8" wood disk as the pusher plate if both were beveled sufficiently?

If i may toss this out... Scribbler, theres nothing here that cannot be done with things like wooden forms and hand tools. A drill press can replace the lathe.

I cut a basic circle out of copper sheet with shears. Doesn't even have to be all that round. A hardwood disk or ANYTHING that fits inside a 2" pipe with room for the sheet as well between former and pipe can act as a support for the rim turning.

I used 0.025" thick copper sheet, which isn't that thick at all, but once the cup forms, it stiffens up a lot. The rim can be folded over with hand tools. The final trick was to simply ram it through a 2" PVC pipe, which worked perfectly. You can taper the input to the PVC section with a sharp knife to make the forming easier.

Just anneal as needed. I may have done three or four annealings on a couple of these.

Remember ONE hole only in the middle until the cup is formed or the holes will stretch. The rest of the holes are drilled afterwards.

Combine a cupped endplate with beaded/rimmed inner pipes, soldering becomes childs play.

Thanks for the reply. I actually had a bit of luck forming a Cupped plate last night at my in-law's farm. (Crazy insane hydraulic press!). My issue was keeping the disc horizontal as it was pushed in. It's kept wanting to tilt and go in on an angle. I fixed that by using longer bottom piece that was also much tighter fitting. (This was working with my 1.5 inch copper tube size, but I am coming to the conclusion that I would rather delay progress find two which to do use instead-even though I have THIS one for free!

My next daunting task will be trying to flange the upright tubes. I could totally see how this would make soldering a breeze. In the past when trying to sort of thing, I have had a little bit of trouble with solder flowing between the two pieces and dribbling away. It didn't seem to matter how tight I had the holes and tubes fit.

How do you deal with this on the bottom piece? I have been thinking about this trying to come up with solutions. One of the things I have considered testing is drywall mud.

In another Internet search on metal casting sculptures, I have heard about people taking a wax figurine and painting it with watered down drywall mud-several coats then melting the wax out and casting metal into it. Would painting the underside of the plate and tubes with watered down drywall unit except the bull way of preventing the hot Sauter from just flowing out?

Additional information on some experimenting I did yesterday. I will try to keep this brief.

1) Drilled out at piece of copper sheet one size smaller than 1/4 inch.
2) Placed it over a hole drilled in a piece of steel that was one size larger than a quarter inch.
3) Took a 1/4 inch wood dowel with beveled edge and hammered it through.

-You can probably guess the results… The copper sheet puckered unevenly because of the stress.-It wasn't sandwiched. I think using top plate to sandwich the copper would fix this.

4) Took a 12 imch length of 1/4 inch copper tubing and flared the end with a flaring tool.
5) Placed the flared end at an angle to a block of wood, and began tapping the other end gently with a hammer while spinning. Increased the angle as needed. Then I tapped on the head of the flared directly until it was a flat flange.
6) Used a combination of woodblock and direct hammer taps to bend the flange backward.

Results: Sliding the copper tube through the hole in the copper sheet, the bent back flare of the tube fit overtop the raised lip around the hole.

Not sure if this description is clear enough to make sense. It seems to me, that this could be one way to solve the problem of solder flowing away and escaping. No annealing was necessary- Which is good, because I am not sure I am confident enough in my ability to do that properly. This was obviously done with 1/4 inch tube. I don't know if it would work with other sized material. It also doesn't do anything to solve the same problem at the bottom.

I thought that perhaps I might be able to flare the copper tubes after sliding the plate on and fiddling with it. I have a hunch that this could be done, but that there would be too much variation in final tube length to make doing it useful. (Unless each flared end sat perfectly flush, what would be the point?

Goodness.... I really HAD planned on being brief. Sorry about that.

Scribbler.

Scribbler, I understand your description... That is awesome work, and really clever! You've got both tube and sheet working together to form an interface for soldering, and I definitely concur that even a small gap in a joint like this means you simply watch the solder drain away to the inside, bye bye, no seal.

If you haven't seen this yet, look at the first picture in this thread

http://homedistiller.org/forum/viewtopi ... 87&t=48484

This simple tool set makes a perfect bead and rim in 1/2" tubing. The piece mounted on the shank is pressed down on a previously flared, then annealed tube, and it folds the rim right over. The trick is supporting the tube, and there are a number of ways to do that without a lathe.

I like your thought processes on using simple drilled formers - can be hardwood, even - to do two things... Dimple sheet copper to prevent solder simply flowing away down a drain, and also hand work rims into tube ends.

On the plain (other) end... In that build, the baby shotgun, I took a page from boilermaker work, where they "spin in" the small tubes into a holed end sheet. I made a little expander tool that gets inserted into the tube, and by turning a cap screw, the tube gets expanded unitl it locks onto the end sheet. In the boiler world, these tubes aren't soldered in, simply expanded mechanically or hydraulically into place, that's how hard it holds.

I'm thinking what I did was way more complicated than it needs to be. I like the idea of a force fits of the small tubing through a slightly undersized hole, or even easier, simply drill and reverse dimple the cap so that it also has a rim around the hole to prevent solder from draining.

Like you described, if you start with an undersized hole, then cold form a dimple, you'll get a raised rim, like a moon crater, AND a hole that is very snug around the small tube. Of course, the small tubes at that end need to poke through and not be flush, both for soldering and for condensate drain. Hope this all makes sense.

There are many, many ways to accomplish the same task, some simpler than others.

Oh man... That countersunk end cap is just gorgeous!

About the flaring setup in the first pic: Do I understand this correctly? -you get a regular flare with a flaring tool, then mount the cu tube under the drill press. The 'rimming' (?) tool is then chucked and spun up on the drill rather than spinning the tube?

Pretty much correct. Get the flare, which can be done with a normal flaring tool, anneal once more, and then the copper is mounted in anything which will both support the tube, and provide a flat surface that the tube rim forms on.
These two tools thread onto that shank as needed. Look closely at the tool on top, and you'll see it has a recessed flat, and a rim. The tool lower right I used to flare. The hardest part for non-lathe guys is holding that tube. There's a lot of pressure on the tube, and it's going to want to get pushed into whatever fixture is holding it, rather than having a rim formed.

There's a tool called a collet block holder that uses a common collet called a 5C. This is machinist stuff, but can be easily mail ordered, and not too expensive. They look like this:



What you'd want is a square block, a closure nut, and a single 5C collet for the OD for your copper tube.

Here's how it's done for 1/2" OD tube: The collet is placed in the block, the tube inserted until exactly 1/8" of the tube is still sticking out. The collet nut is tightened, and the tube is now captured.

The collet block is then gripped in a vise and set on a drill press table with the copper tube extending down through the drill press table center hole. 5C collets are hollow; stuff can stick out the back end. I mounted the flare tool (lower right) and with some lube, pressed it down firmly to make the flare. Formed the flare on all the tubes, annealed them again, then swapped tool tips to the recessed flat job.

The copper tubes were inserted into the collet until the flare prevented them from going in any further, the rim tool was set on the shank, and the rim formed with the same sort of motion; lube, moderate speed, strong pressure. The rim folds over flat on the collet and gets sized and formed by the recess in the tool.

5C collet stuff is available... flare tools also available. But the rim tool is something I made, and I know of no commercial device that replicates it. They need to be made for a specific diameter. Here's the thing - My guess is, if you mount a simple steel round in the drill press with a flat end (polish the end nice) and simply press down hard, you'll get an excellent rim. They might not be as consistent or pretty, but the rim diameter can be reduced with hand work, files, etc.

The key to all this is holding the tube, and that's where a 5C collet, and a collet block, are key. They can be found on eBay with ease.

Sorry for the lengthy post; hopefully it'll help some one.

Lol!!! I just reread this thread and saw something I missed the first time!!! You are using 1/2" OD tubes---- somehow I had been assuming you were using 1/2" ID tubes!!!

So is the ID of a 1/2"OD Tube actually 3/8" then?

Scribbler wrote:Lol!!! I just reread this thread and saw something I missed the first time!!! You are using 1/2" OD tubes---- somehow I had been assuming you were using 1/2" ID tubes!!!

So is the ID of a 1/2"OD Tube actually 3/8" then?

Close, it's 0.500" OD, 0.432" ID, and to a plumber, it's 3/8" copper pipe... what a dumb system.

I think for a 2" OD shotgun, it's a good dimension for an inner tube. For a 2" dephlegmator, I'd go to a 5/8" OD or 3/4" OD pipe set.
.

BigSwede wrote: even a small gap in a joint like this means you simply watch the solder drain away to the inside, bye bye, no seal.

I hate to sound like a hacker, but when I have a gap in a solder joint, I wrap a piece of copper wire around it. You can get magnet wire cheap at Radio Shambles down to 30 awg or so. If you leave the coating on it actually turns into flux when it gets hot enough, but sometimes it stinks so I like to take it off with sandpaper. Fold a piece in one hand, draw wire through with the other. Quick and dirty.

I'dBeLessOfAHackerIfIHadALatheSkow