1/96 Thor Permit

[subdude]

Mike, just noticed where you're located. It would be a bit of a haul, but this Sunday is our monthly SubComEast run. We meet at the YMCA in Shrewsbury, PA, which is right over the PA line from MD straight north up I-83 from Baltimore. We're there from 10:00 until 1:00, then have lunch and BS meeting.

Jeff LaRue comes up from the Annapolis area, maybe you could catch up with him and carpool if you didn't want to make the drive by yourself. We have folks from Philly, Harrisburg, Wheeling, WV, etc come every month. It's a great time, we would love to meet you and see your boat!

Jim

[Parallax]

Hi Jim,
This Sunday I am going to be at a family reunion in Norfolk, but I would love to come the following month. When is the next meeting? I will be there for sure plus I need to pick your guys brains for improvements to what I have done so far.
Mike

[subdude]

Mike,

Second Sunday of the month, October thru April. Same time and place. Email me and I can send you more info. We would love to have you join us! emailJimButt@gmail.com

[Parallax]

Jim sorry I have not had a chance to write you, I will try to do that today/tonight. I am looking forward to coming.

I finally got a chance to take out the Permit to a pool for the first time. Some things went well, some did not but I think it was a good learning experience and I am zeroing in how to make everything work better. By the way, this sucker is fast when you punch the throttle. Was not really expecting that and its kinda awesome. I found in order to keep in under control I actually need to slow down (for now).

The biggest issue I ran into is the range of the radio and have clearly done something wrong. It is maxing out a about 25' - 30' on the surface and loses contact about 6-12 inches below the surface. I believe I may have gone about 2 inches too short with the external antenna. Would that be a serious issue with a 75 mhz radio?

I had a lot of binding issues with the linkages but I believe I have made adjustments now that will make them work much better. I am still having issues with the original rudder and plane mechanisms and need to address them sooner or later. I also learned how to restrict the movement on the servos with the transmitter as there was too much range of movement. The servos I have are smaller then the mounting area and there was a lot of flex. I altered the location of the mounting towers for a better fit. Feels much more secure now.

I drilled a hole on the WTC next to were the Pitch Controller is mounted and have the sub at what appears to be a pretty good zero bubble after calibrating it on a level. I am not sure where I should set the sensitivity at.

I found that the sub has a hard time steering, especially trying to make tight circles and I wonder if there is not enough surface area on the rudders. I was thinking about adding some clear plastic to them to increase the surface area of the rudders. Has anyone ever had this issue or solved it that way?

Another issue I am running into is that a lot of the glued components are falling part. I attribute that to the age of the model and I am using epoxy to fix it as i go.

Hopefully Ill have some pictures posted soon!

[thor]

What radio system are you using and what modifications did you make to the rx antenna?

The permit is capable of turning within its own length. It is one of the most capable boats you can build. You have it either trimmed improperly or your linkages are not allowing enough rudder deflection.

What do you mean "glued components are falling apart".

[thor]

I have dug through your post here and I can see you are using one of the excellent VEX transmitters. I can only see the edge of what appears to be a Subtech Rx with VEX crystal? You should have no issues what so ever. However, if you modified the antenna at all that is the likely cause of your limited range. The micro receivers utilize single conversion crystals. They function extremely well but are super sensitive to antenna length and deployment. Hopefully, you didn't trim your antenna?

[Parallax]

I am using a 75 mhz VEX 6 channel transmitter and subtech receiver I got from Bob. and I just saw your post. I completely screwed up and cut the receiver antenna so I could connect it to the pass through bolt in the WTC that connects to the receiver wire built into the wtc. ugggh

I'll try and take pictures of the linkages tonight and how far it deflects. I have no doubt I screwed up putting the linkage together. I can also take some pics of the trim and where all the weight and flotation is.

I am actually not sure if its glue or epoxy but some of the components that where assembled on the hull such as guide tabs, Velcro straps, etc have started to break free after having been exposed to water. Honestly this is not a big deal as I am just using epoxy to re secure them.

[SubtechRC]

Ok...I never like cutting the manufacturers antenna. Not a good idea! It so much more critical on these super micro receivers with single conversion crystals. Much better to pull that unit and place a brass tube in its place, then connect a piece of model airplane fuel line that is longer than the antenna. Run the antenna through the tubing and let the tubing lay in the free flood area. Remember to plug the open end of the tubing with brass rod or bad things happen!

Pack up the receiver and send it off to me and I will repair it for you and retune it.

[Parallax]

Thank you Matt, I just sent you an email. I am going to reinstall it exactly how you described.

[Parallax]

Can anyone offers suggestions about what I should do about the rudder and aft plane linkages? The are pretty rusty, and there is a lot of contact and binding going on back there. I have a feeling its going to require cutting into the hull or just learning to live with it. The biggest issues I am running into is the yoke controlling the rudder is constantly making contact with either the plane collar or connecting linkage. There is also a lot of binding in general going on with the planes. The rudder yoke is also making contact with the hull at certain angles. From what I can tell it looks like the collars are not stainless as well as the connections. Its very tight int there so I do not think I can out right replace anything without cutting into the hull

[Guest]

A bit of a mess you have, but most likely salvageable. Avoid hacking the parts, because you'll almost certainly damage the rest of the hull, and that will mean even more work Looks like the collars are brass, but the grub screws are steel. They will have expanded inside the threads, and will be difficult to remove as is.

If you have a dremel, I would use a very small rotary wire brush and tryb and clean as much of the rust off as possible, remove the linkage rods to assist with access.

You can then try applying some penetrating oil, but it may not be sufficient, and you may not be able to get an allen key in to get some crank on the grub screws. Do not be tempted to try and remove the grub screws as they are.

Another method to clean up rusty parts is to use electrolytic rust removal. Sounds very technical, but you only need basic stuff to do it, and it works very well. I tend to use it on old car parts that are difficult to de-rust using standard mechanical methods, and it is able to get inside threads, and delicate areas, without being destructive.

Here is a good explanation of the process and what you need to do it.

Electrolytic rust removal is a simple non-labor intensive method of removing rust from an object, using nothing more than water, washing soda, and electricity. There is nothing magic about the process; anybody old enough to remember chrome bumpers remembers the electroplating process. In the case of electrolytic rust removal, the system is plating rust from an object you want to restore onto a junk electrode.

The same process is also very effective for removing corrosion from brass and copper, using the same electrolyte.

The process is NON destructive, to the steel or iron object being derusted, unlike media blasting needle scaling or acid dipping. The only thing that will be removed is RUST. The best part, unlike abrasive blasting, ALL rust will be removed from the microporosity of the metal being derusted. When all rust has been removed the process will STOP by itself, and good steel will not be eroded.

The process does NOT restore the metal to original condition, it merely removes RUST.

When done PROPERLY, with Sodium Carbonate or Sodium Bicarbonate, electrolytic derusting will NOT harm steel, Babbitt, lead, copper, brass, or aluminum. That means with a properly sized tank, you can submerge and derust a complete Hit & Miss engine. Using other electrolytes can and WILL harm some metals, such as Babbitt or Aluminum.

SPEED: Lets face it, the object you want to derust didn't get rusty overnight, and electrolysis will probably NOT derust it overnight either. The speed of the process is determined by equality of surface area between the object being derusted, and the accumulating electrodes, as well as by the voltage/amperage applied, and the electrolyte used.

Here's a brief explanation of what is happening in the tank:

During the electrolysis as a general rule, ions are being replaced vs elements. So the Ferric Oxide is probably being converted to Ferric Carbonate. Also any pollutants that are in the original water and any contaminants on the part being derusted will lend their ions to the mix. There may be Calcium Carbonate, Sodium Chloride and who knows what else in there. Basically there will be Hydroxyls, Carbonates, Oxygen, Hydrogen, Sodium, Iron, and maybe some Calcium or Chlorine in the soup. The only compounds that will be lost will probably be Hydrogen and Oxygen; anything else will remain in the soup as soluble salts (some Sodium Carbonate and maybe Ferric Carbonate) or as solids which will either precipitate and fall to the bottom, remain suspended in the soup, attach to the anode or remain on the surface of the derusted part.

I'm just a dummy who knows the process works.

Solution: 1 tablespoon of Arm & Hammer Super WASHING soda per gallon of water. This is the BEST working solution for the electrolyte. On the off chance you can't obtain Washing Soda (sodium carbonate) in the supermarket laundry aisle, Baking Soda (sodium bicarbonate) will work, although it will offer slightly less productivity in the tank.
Over time, the solution level will drop due to evaporation and the breakdown of water into Hydrogen and Oxygen. Only water needs to be added to replenish the solution, no additional soda needs to be added.
If the tap water in your area has a high mineral content, using demineralized water may yield better results.

The solution will freeze, at about 30° Fahrenheit. Generally this isn't a problem, at least for me, because I don't enjoy working in a cold area. If the solution does freeze, it will easily thaw by applying voltage to the object being derusted and the accumulating electrode. Freezing will NOT harm the electrolyte solution. Frozen solution may harm some objects that are suspended in the solution when it freezes, so use common sense.

VOLTAGE: The process works best with either 12 or 24 volts DC, easily obtainable from a battery charger. Voltages above 24 volt don't really offer any greater efficiency, and generally seem to get wasted off as heat in the solution. Heat doesn't add anything to the process, other than wasting electricity.

AMPERAGE: Basically any DC voltage source will work, from a trickle charger to a plating power supply. Too much amperage, just as excessive voltage, wastes off as heat. The best way to regulate the amperage operating in the tank is by controlling the amount of submerged surface area of the accumulating electrodes.

POLARITY: Positive (+) DC is attached to the accumulating electrode, and Negative (-) DC is attached to the object being derusted. All you really need to remember is Positive Accumulates. If the polarity of the DC source is not known, attach the wires and energize the system. Small bubbles will rise from the NEGATIVE object. Correct a reversed connection immediately; allowing your prized object to accumulate material from the sacrificial anode can rapidly cause pitting. The bubbling is also a good way to verify that the process is working.

BATTERY CHARGERS - If you use a charger as a power supply, some of the newer "automatic chargers will not start generating current into the tank, unless you use a battery along with the charger.

ELECTRODES & OBJECTS BEING DERUSTED - Both need to be suspended so they cannot come into contact with the bottom of the tank or the sludge that accumulates there to prevent shorting the power supply, or wasting current by passing it through the sludge.

TANK - Plastic tanks work about the best, and that includes digging a pit and lining it with plastic sheeting. Unfortunately, my neighbor has taken an attitude, so I haven't been able to experiment using his pool as a tank, but he might go on vacation. The process can be done in a steel barrel, BUT exterme care needs to be used to preclude the barrel from becoming an energized surface, witch will eventually develope poroscity in the barrel.

The best anode material I have found is carbon or graphite. It works 24/7 and leaves the rust in the bottom of the tank, so you don't loose time cleaning the anodes, or loose operational speed due to coated electrodes. If you can't locate graphite electrodes, used lawnmower blades or old car leaf springs will work but they will require cleaning about every 4 hours.

Whatever you do, DO NOT use stainless electrodes; they make some very nasty hazmat called Hexavent Chromium that is POISONOUS and will give you nasty diseases, and it is absorbed through your skin.

The process works best "line of sight" so to speak, so multiple electrodes are often beneficial. Arranging several accumulators around the perimeter of the tank generally works well, and minimizes the possibility of short circuiting.

SCUM: As the process runs, a layer of brown (usually) scum will form on top of the solution. This doesn't happen 100% of the time, but a scum layer is not anything to worry about. Before withdrawing the object being derusted from the tank, it's a good idea to shut off the electricity, and skim off the scum before pulling the object.

[Guest]

CLEANING: When objects are removed from the tank, they will often have a black coating that looks like the object has been smoked. This is normal. The best way to remove this coating is to wash it using a stiff brush in a solution of dish soap and water before the coating dries. If the coating is allowed to dry on the object, it will be nearly impossible to remove.

DRYING: After washing derusted objects, the best procedure is to either sun dry or dry in a 200° oven. If you use your wife's oven be prepared to sleep on the couch, not that drying will hurt the oven but it will hurt your sleeping arrangements.

CONTAMINATION: In order to avoid contamination of the electrolyte solution, objects being derusted should have all grease, oil and dirt removed beforehand. Objects that have rusted in a salt water environment such as ocean water need to have as much salt leached out as possible, before electrolysis. Failing to remove salt first will radically shorten the useful life of the electrolyte solution.

CRACKS, etc.: Objects such as multi-piece assemblies that have mated surfaces are difficult to derust without disassembly. A great amount of time will be required to electrolytically remove rust between the sliding surfaces such as a vise. Pieces that have cracks will perform similarly in an electrolysis tank, and it will take time to remove the rust from the crack.

MULTIPLE PIECES: Assemblies of multiple pieces (such as machinery) usually require an electrical connection to each piece. Rust does not conduct electricity, so unless the pieces are connected cleanly together, generally the connected piece will derust while the adjacent piece remains rusted.

CONNECTIONS: It is necessary to make a good electrical connection to the object being derusted and the power supply. As previously stated rust is not electrically conductive, so it may be necessary to scrape or grind a connection point on the object before the process can begin. Alligator clips are generally acceptable connectors BUT solid copper clips should be used. The cheaper plated steel clips will usually self erode when submerged in the tank.

Accumulating electrode surface area relative to area being derusted governs both achievable speed and amperage, but you need to be careful because you can get the solution damn HOT.

Also remember, this process generates Hydrogen gas, so take appropriate precautions. The area immediately above the tank is a PERFECT atmosphere for a very rapidly burning fire, often called an EXPLOSION by uninformed people who are in the process of explaining to the fireman filling out the report next to the big red truck. Electrolysis breaks water down into it's 2 basic components - Hydrogen and Oxygen - and when they are recombined by ignition of the mixture, the fire burns at about 4280° Fahrenheit. Keep ALL potential sources of ignition away from the top of the tank and surrounding area.

For you speed freaks, don't even think of hooking up the DC welder to get faster results. It is possible to boil the solution, and that really sucks in a plastic tank. NO, I didn't do it and had I been the speed freak who did, I certainly wouldn't have posted that brilliant move.

Much information has been posted on the web suggesting using lye, caustic soda or drain cleaner for an electrolyte to speed up the process. This is BAD information, and the use of lye is dangerous. There is also no appreciable increase of process speed achieved using lye, so I don't see where taking the risks associated, and dealing with the HazMat created or safe disposal of caustic solution is worth it.

[apa-228]

We used to use a warm Coca-cola to remove rusted manhole covers in streets and roads. You could give that a try and it is a cheap alternative to a lot of other stuff. We also used Kroil brand penetrating oil in the powerhouses when removing large studs and nuts and valve parts. It was able to penetrate oxide scale caused by superheated temperature steam. The biggest problem you will be facing will be the damage to the allen screw pockets.

[Guest]

It's the phosphoric acid in coca-cola that de-rusts. I think in this instance the electrolytic technique will work faster and it's easy and cheap- you just need a small power supply and some washing soda and a sacrificial anode.

I agree that the hex sockets maybe too far gone to get any grip with a key, but you may be okay. Can only see once the rust has been cleaned back.

[chips]

The collars are nickel plated brass with arms made from brass stock soldered to them.