TMS-20 update

Update from the Man Shed. It has been awhile since I’ve posted an update. Work on the TMS-20 has been slow the last year. I’ve been busy with a few large projects at work and family. I have 6 weeks left in the states then I’ll be back in the Mediterranean again for 2 month working on a new cruise ship in Italy the Carnival Breeze. Most of the work and planning is complete and everything will be shipped by the end of the week, then a trade show next week and I’ll have a bit of breather time before I leave. I hope to slide in some vacation time in before I leave. So far the rest of the year looks slow so I can catch up on the boat. That’s the plan anyways.
I’d like to get the outside skin on the hull before I leave. I’m in the final faring stages of the hull seems like it has taken forever. I’ve been working on some issues with the vacuum pump system by adding a cut-out switch and will be using breather cloth in the bagging process. I hope I can catch some good weather before rainy season starts. I’ve been thinking about setting up a webcam in the shop now that I’ve got internet back to the building. More on that once it is set-up. I figure some would like see the madness of a bag-out.
Just one pic to share. Later….
Mike

If you are getting that limit switch from the veneer supply place, I had problems running 110V through it with contact bounce. It would cycle madly at it's setpoint for about 4 seconds causing my pump relay to also cycle madly (sending fits of voltage to the pump motor). I added a PLC to the system to debounce the sensor but converted the sensor to 12VDC operation since it was simpler with the PLC - it didn't bounce any more with DC voltage...you may need to consider that if you are using the same sensor.

How can anyone who is this smart sail across a lake in his PJ's with his beach wheels dragging behind his boat?

I bought the switch and relay from ACP Composites. I'll let you know how it works.

easy....RUM

And the plugs out.
CLASSIC!!!

hey, even Einstein had his moments!

Just as gin makes a man mean, rum makes a man stupid.

We won't talk about what tequila does to women.

<quote>How can anyone who is this smart sail across a lake in his PJ's with his beach wheels dragging behind his boat?

And the plugs out.</quote>

Fits the mad scientist profile perfectly!

Portsmith rating on this is.........

Yeah, that's right! I should get a modifier for towing beach wheels.

Jake can you tell me more about the knock down and PLC you made for the pressure switch?

I had a PLC laying around (Allen-Bradley Micrologix 1500)...but you can get them on ebay for around $100 to $150 used (they just went obsolete so prices may be skyrocketing). The AB programming software is expensive so I wouldn't do that unless I had work access to it (fortunately, in this case, I do). There are other affordable PLCs that come with free programming software. As I said earlier, my intent was only to debounce the limit switch with some logic so it would have to reach a steady state for a few seconds before the PLC would turn off the pump. It migrated from there into a completely overthunk, overdone piece of hardware - but it works great. I later put in some sequencing for the restart of the pump (so it wouldn't have any vacuum on it's input when it started to prolong the health of the pump) and I setup a series of 4 switches that I could use as a timer so I could have the pump quit cycling after some period (after I had gone to bed or work, etc.).

For the vacuum stage sequencing, I installed a smaller reservoir (1.5" PVC about 8 inches long) on the input side of a three-way Mac pneumatic valve (110v). My vacuum pump intake is tee-d into this smaller reservoir. On the other side of the Mac valve is the primary vacuum reservoir that consists of three linked lengths of 6" PVC tubing (and the adjustable vacuum limit switch). The Mac valve switches between venting the smaller reservoir to the atmosphere (through a very fine and restricive brass bead filter) and connecting the small reservoir to the big one. When the pump is turned off and the Mac valve disengaged, the small reservoir takes about 20 or 30 seconds to vent through the restrictive filter on the intake of the mac valve. When the limit switch sets the demand for more vacuum, the PLC fires the pump relay. The pump starts but only initially sees the atmospheric condition in the small reservoir (instead of being hit instantly with the nearly full vacuum in the reservoir). After four seconds, the smaller chamber has reached a pretty significant level of vacuum (the brass filter doesn't let much air flow through) and then the PLC fires the Mac Valve to connect the small reservoir and the primary reservoir (bypassing the brass filter so everything is now sealed to the pump). The pump is now pulling both reservoirs down until the limit switch is satisfied and drops the demand signal to the PLC. On shut-down, the PLC disengages the mac valve to make sure the main reservoir is sealed and then the PLC turns off the pump about one second later. At this point, the smaller reservoir is slowly venting to the atmosphere so it's ready to start over again.

With the timer, I have 4 switches that set a binary timer. When the timer is active, I have an indicator light that flashes once a second. The indicator light also flashes very quickly when the demand switch has changed state to make it easier to adjust the limit switch for different vacuum settings (which I found to be important since the on and off sequence became complicated and is not instantaneously obvious). The switches tie into discrete PLC inputs and any change in state of any of the switches resets the timer to the new value. They're set as follows

0000 - no timer..pump cycling full-time on the limit switch as long as the unit is plugged in and has power.
0001 - 1 hour off delay
0010 - 2 hour off delay
0011 - 3 hour off delay
0100 - 4 hour off delay
0101 - 5 hour off delay
0111 - 6 hour off delay
1000 - and so on.....
....
1111 - the limit switch is ignored and the pump is engaged 100% of the time

And yes, this was absolute and complete over m-f'n kill...but this was back when I had time to play!

oh yeah, and my pump relay also energizes a standard 110V outlet on the reservoir assembly so I can plug in a small desk-type fan that will cycle on and off with the pump to make sure the pump head stays cool if it's on a big (leaky) job where it will be running a lot (I've had some overheating issues in the past with it).

and the flux capacitor is ... where?

Well Jake it sounds pretty complicated. I'll go with my set-up and see how it works. My computer and networking background is not ready for something as complex as PLC. Sounds very interesting though!
Were you using any Siemens controllers? Better check for the Stuxnet worm. I hear they were having a bit of a problem with that in Iran. What an amazing piece of engineering behind the Stuxnet worm. There is a good story about it in the New York Times on line.

What od you do for work aboard the cruise ship?
Tom

I work for a company that builds Inter Active TV systems. We are a systems integrator. We have software packages and we integrate with electronics including video servers, encoders, modulators, set top boxes, and tie all of this together along with the ships broadcast signals on-board and satellite signals add the electronics needed to make it all show up on the TV’s and mobile devices if they purchase that part. We interact with the ships management system so you can check your balance, shop, and purchase movies. Also we have a casino module and our own system, using our App so you can use your cell phone without going through say Ma Bell so it’s much cheaper. Almost everything that you can do on the TV you do from a mobile device with our new product. If you have been on one of the larger newer cruise ship most likely it had our system. So we do just about everything that makes the TV work except the TV’s. Install servers, networking, electronics, software, and programming, make custom remotes, and install an electronic box in each cabin that connects to the TV. Then tune the signals from each of the components. We also will build custom software modules to customers specs.

Me personally I am the project lead once the contract is signed I take it from there ordering materials, logistics, manage the customer, manage travel, manage the project on-site, and get sign-off for the project.

Also I’m responsible for everything that goes wrong. The cool part is I usually get to go on the maiden voyages for a week or two to make sure everything is working properly.

Remind me to punch you in the brain,the next time I see you.

Are you going to have a clearcoat finish on the carbon?
that would explain why you have gone to all that filling and fairing effort before the final skin.

and one more thing I just remembered, the staging sequence on the vacuum also allowed me to eliminate the spring loaded check valve that was reducing the maximum vacuum I could achieve in the reservoir.

Paul,

The thought has passed my mind but I think I will paint it with Awlgrip. The sun is brutal in South Florida and black would be just too hot and probably not the best for West Systems Epoxy.
The Awlgrip paint job I did for Cyberspeed has held up really nice for the miles he raced the boat and for being kept on the beach.

All the fairing work before the outside skin is because the skin is not very thick. The basic lay-up for the outside is two layers of 200 gram uni carbon for strength and layer of 600 oz uni Eglass for protection.
I wanted the final skin to be mostly glass with very little filler. I had a fear of cutting into the skin while fairing cabon sands very easy and cutting into the skin would not be a good thing. If it was a thicker lay-up I would not worry as much.
There are stress points that will have 4 layers of carbon like the opening for the ****, around the mast step, bow point, and the bulkheads that support the mast and main sheet block rack.
I will use a router and shave that area down for the extra thickness of the lay-up and overlaps of the cloth.

Originally it was going to be used for a plug after I sailed it but I decided that it was not quite close enough for plug quality so I decided to make it a prototype mule if you will and get it in the water.
Then if all goes well and there is interest I’d like to build a plug by CNC or just a dedicated plug with any design changes that we come up with.

All in all it has been a fun project and I can’t wait to get it in the water and see what all the work has been about.

Jake do you have a picture of the set-up?

is that 2/200g carbon and 1/600g e-glass?

Thanks for the responce. That is quite a detailed job. I was asking because early in my career I did a one year contract with a well known cruise line. What a tough gig and even tougher life style. I worked the kitchen as a saucier and rounds cook. It was a great experience none the less. What you walk away with more than anything else is great organizational skills. The other thing is customer service. This stays with you throughout your career. I left the cruise line as a sous chef in the main kitchen. Do you go out on the ship during a cruise or are you there doing your work prior to the boat sailing? Thanks,Tom

Tom ship life is tough, working through a couple of ship contracts will make you enjoy a normal life that is for sure! A larger percentage of our company came from the cruise lines with many years experience. Some of our work are refits so we actually work while the ship is in service, makes it tough with customers on board, but when we are not working we get to enjoy ourselves a bit. This trip will mostly be at the ship yard during the final construction, then the first revenue voyage. If all goes well during the first voyage I will be in a “stand-by” mode just in case something goes awry.

Paul oops 6 OZ Eglass