Some very good info on Teflon tape & "pipe dope" in this thread:
http://ths.gardenweb.com/forums/load/pl ... 28034.html Personally I haven't used Teflon tape in many years. I either use RectorSeal or TFE Thread Paste on all my water & gas projects that require a thread sealant.

PictureThyme wrote:I think the engine turning, or guilloché, is quite beautiful and Paul's machines look great finished that way. This is one of Paul's images (borrowed without specific permission) for illustrative purposes.

That is commonly referred to as a jeweled finish or jeweling the metal. We do it on guns for decorative purposes and it has some functional purposes as well. The micro groves created from the polish etching will hold oil for a smoother action. If you want a smoother trigger you go to a gunsmith and have the action jeweled.

I think it's time for an update.

I believe my A1 should have had the computer integral to the push button box for brewing coffee. I think this was a replacement CPU because it is designed for 4 groups--at least that's what the markings on the board say and as evidenced by the four 8 pin connectors. The plastic enclosure was held together with silicon and had cracked. Generally, it didn't look so nice. Also, newer models have a small fan mounted near the box to keep it cool since it sits next to both boilers. I thought I could do better. So, I mounted the CPU to a scrap piece of aluminum and mounted that in a project box.


I found the scrap metal box and some parts and thought they would be perfect for making a new enclosure for the machine's CPU and the new PID and maybe some other things like LED lighting somewhere down the road.

I also did not have the key switch so I used a scrap on/off key switch for that as well.
When it's done, I plan to put a Lexan cover on the box and mount the whole kit under the machine. It will fit underneath with some 4" legs and will sit behind the legs so it's basically out of sight.

The front cover where the PID and the switch are mounted will, some day be black, or red, or maybe "grain" it when I get to the finishing of the other cover parts. Also, looking at the picture, it needs a little squaring up.

I've asked a colleague at work to help plan some electrical wiring for the two 5vdc fans that are mounted in the box. When I've gotten a little further with the wiring, we'll see if one of the 3 unused group connectors has a 5vdc output and ground to power the fans. He seems to think this would be a good solution for powering the little fans. They're only .095 Amps each. I'm a bit skeptical since he's used to wiring lasers.

When I was taking apart the machine, I noticed that the screws holding the main power switch together were loose.

The culprit was cracked washers at the back of the switch. While attempting to replace the washers, I learned a great deal more than I wanted to about the mechanics of the switch. When the two screws running through the power switch were taken out a few little things fell out.

The small oval steel piece in this picture holds the main shaft into the switch so when it's pulled it doesn't come out. One of the two through-screws threads through this holding it in place against the shaft. The shaft has a small groove cut into it where this connector fits. It's one of the last pieces to go back in before the screws are reinserted.

The switch is actually three, or two, sets of cams and contacts that are actuated by turning the power switch. The three sections of the switch are identical. In this picture of the cams the switch is actually in the "OFF" position.

*Neither set of contacts makes an electrical connection (the contactor slipped out of it's track in this picture so there is a connection in the picture, but wouldn't be if the whole thing was put together). If you have to attempt this for any reason, I found it's much easier to put everything back together in the "Run" position--both of the contact springs are extended into the indentations of the cams.

The three cam sections are held together by a front and back cover. the front cover houses another cam and springs that allow the switch to move in only three positions. Off, Fill and Run. You can barely see the groove cut into the drive shaft where the retainer will sit when the entire switch is back together. The trick is to sit all three cam sections in a row to make sure the cams are all in the same positions. Then once you've sandwiched the three cams together, you will set the limiting cam all the way to the right, or Run position. This way when the whole thing is in one piece, everything should be in sync.


I had this put entirely back together last night and thought I would be nice and take the whole thing apart again to take these pictures. Of course springs and contacts were flying everywhere. Yesterday, it seemed the switch was a bit easier to move and I am considering taking it all apart to see if I can't figure out what's changed. I do remember though, that the first time I plugged in the machine and moved the switch, there was considerable resistance to turn the switch.

*Edited because after reviewing the picture the cam is in the OFF position.

After rebuilding the steam boiler with the old heating element (I know, should be replaced), I filled the tank with water just to test it out. The sight glass and the pipes running to that were not leaking. The boiler end cap wasn't leaking but the nuts holding the heating element were weeping water slowly. Ugh!

I tried, as Paul had told me to tighten the nuts up pretty snugly, but that didn't work. I tried with teflon, without teflon, with teflon and with copper washer and copper washers without teflon. Are you tired yet? I was. Still leaked. So, I ordered a new heating element. Repeated the whole process and got the same results. Leaks.

This time I took apart the tank, and took some pictures. It was suggested I use a whole bunch more teflon to seal the leaks. There has got to be a better way. I noticed looking at the end cap, the holes for the heating element are counter sunk inside the tank and thus causing the leaks. Does anyone have any suggestions for a better way to seal this? Does some company make angle washers to better fill the connection? Thanks in advance.
Steve

Looking good Steve!! Sorry I cannot offer advice on your weeping heating element nuts, I have the other style. Just wanted to stop by and cheer you on!!

PS: Your starting to make me feel like I rushed my rebuild!!

I noticed that the washer for my thermocouple was a compressible copper type. It looked sort of like a bagel (kind of fat but soft in the middle). It compressed while I tightened to fill any gaps. Maybe something like that might work?

Could you show better pictures of your box? I have been thinking of ways to move my computer to a cooler location. It amazes me that they mount the computer directly above the grouphead!

I've always used the copper washers there and given them a small smear of sealant for good measure that seems to do the trick. The fiber washer that comes with the level probe is also another good one.

However I do have some 3/8 size teflon washers somewhere, these are used in the ball joints of the steam wands. They would work I reckon.

Your plate looks very clean and no nicks so it must be the copper washer that is not sitting right.

mitch236 wrote:I noticed that the washer for my thermocouple was a compressible copper type. It looked sort of like a bagel (kind of fat but soft in the middle). It compressed while I tightened to fill any gaps. Maybe something like that might work?

Could you show better pictures of your box? I have been thinking of ways to move my computer to a cooler location. It amazes me that they mount the computer directly above the grouphead!

I've considered purchasing correctly sized crush washers, same style used on the theromcouple well, as well. When I took the machine apart, I must have tossed all the old washers figuring I would just order new ones. I don't know why I saved every other old piece and not the old washers. Unfortunately, I didn't even take pictures of this part before I completely dismantled it. Thanks for the suggestion.

I will take more pictures tonight. Most of the screws, I bought at Home Depot.

Paul_Pratt wrote:I've always used the copper washers there and given them a small smear of sealant for good measure that seems to do the trick. The fiber washer than comes with the level probe is also another good one.

However I do have some 3/8 size teflon washers somewhere, these are used in the ball joints of the steam wands. They would work I reckon.

Your plate looks very clean and no nicks so it must be the copper washer that is not sitting right.

I tried your suggestion of torquing the fixing nuts pretty strongly. I even managed to imprint the layout of the end cap into the copper washers-- still leaked. There's a company near my office that specializes in screws and nuts and I am thinking of stopping by there with the parts to see if they have any specialty washers that would fit and fill the gap; maybe try to get some teflon washers. The washer that's spec'ed is the L100/A1 copper washer, at least on the schematic for the heating elements from LM. I think my boiler end plate is a really early design.

Lesson for those who endeavor to do this in the future. If you take 100 pictures and think it's enough, take 100 more just in case.