Screw Loose

Well I got on with the periscope mechanism the last couple of days. Comes pretty much self contained in the box, but with a few crucial bits to get right.

I read through the assembly instructions, which arent much good, but the drawings are very good and accurate. I got the aluminium lid, and carefully measured out all the exact measurements and size of holes to be drilled. And when I measeured it up actually on the hull, I realised the drawing is "viewed from the rear". Basically its the wrong way around !
So after another set of measurements, and centerpopping the holes, I got to assemble it. Just looked at the drawings, and read through the instructions.


Was all going so well until I connected up the motor. It ran for the first few cm's, then stopped. I checked all the drawings, and measurements, and everything was ok there. I then got the threaded rod, and ran a M4 nut down both of them, damned tight. So after re-cutting the thread it runs well. And then re tapped the thread on the periscope mounting bar. All is well

Connected the motor up again, got about 5cm's further down the bar then last time. Got the meter, battery ok, pulling very few amps, but still motor wont turn over much. Used 4x 6v batteries, and all the same. Just as a test I put a 12V battery on, and hey presto, works like a dream. And heres me thinking that my mechanism is jamming, but no, pulls the same amount of current no matter if its a 6v or 12v battery. Starting to doubt the motor. Connected up 2X 6V batteries, and still motor doesnt turn over that well.

Now I have checked with a Vernier Gauge and all masts and pillars perfect. I then got a Tachometer and put it on the end of the motor, got it running with a 6V battery, and it ran at 800 RPM. Supposed to run at 3000!

So back to the drawing board !

Anyone ideas welcome

subzero

Hello Paul,
Thanks for the updates.
It sounds to me like the motor you have is a 12v item and not 6, if its ok on 12v but then doesn't have enough grunt on 6v to run the mechanism, which will have quite a large coeficient of friction by the nature of its design.

Try a known 6v motor on the drive and see if that works ok then you will be in no doubt.

Hope its of some use.

Regards Sub.

subzero

Hello paul,

Just read your post again.

You say " I put 2x6v batteries on and the motor doesn't turn over that well "
but with a 12v batt and it did ....Forgive me but you did wire the 2 x6v batts in SERIES not parallel didn't you ? ie pos to neg on the batts then pos to motor and the neg from the other batt to the motor ??.

regards sub.

Screw Loose

Hi Sub, what I done was hooked up the 2-6V batteries in Parrellel to see if it was just the batteries not having enough power. But the batteries I am using are the Robbe Cyc units, 5aH's. So I thought 2 together to give it a bit more power.

I then got a 12V battery to test the motor, and as I said it went no problem. I am starting to agree with you, think they have give me a 12V motor. I mean its not heating up, and only puling 0.45 to 0.55 amps under load. (exactly the same as when I use 6V batteries) I even ran it continuousley for 5 mins on a 12V battery and it wasnt hot, and worked perfectly.

Got to be a 12V motor! Maybe

Paul

Mankster

Oh yes, forgot to mention that the chain drive put less tension on the threaded rods (does not pull them togeter) so its easier for the motor to turn them.

Screw Loose

Well, I have put the periscope mechanism aside for a little while. I have E mailed Engel themselves to see what they say about the motor for the periscope. So awaiting there reply.

So, while trying to take my mind off my hangover from last night, I thought I would fit all the inner workings into the Watertight box. As I have previousley said, I should have taken advice and made the opening much larger.

It is possible to get the piston tanks in, but trying to get 2 tanks in and the mounting plates and other ancillary equipment is nigh impossible! You have to have hands like a watchmaker to get the damned stuff in!

The first thing was to fix in all the ballast. Just 2KG's of lead shot. Placed carefully in the bottom of the hull, and covered in resin to keep it in place. Amazing how much of the stuff I used to fix it in, and I floated out the garage when done! Even with a breathing mask.

When it was dry, I tried to put in the tanks and the base plates inside. trouble is the opening isnt big enough to mount the fixing brackets when its inside. So I had to drill a hole in the boards and use a Jubilee clip to fix them in. I know a bit rough but it works well and is easily removed if neccesary. As long as its not overtightened it should be ok.

Trouble is all the servos and pressure switches are so far inside you have to mess around for hours trying to fix the damn things in! But after much swearing and throbbing heads and hands its mostly in. Its a good excuse to re-wire it and tidy it up a bit as well.



Trouble is a lot of the wires of which I was foolishly hoping to keep in place have become detatched. So I need to re-wire the tanks again, but at least its all fixed in

Next on the adgenda is to fix in the diving plane mechanism. Its fixed in place just need to wire it up again.

Now where are those Elastoplasts, bloody cuts all over my hands !

solo

Many thanks for the picture of the wtc. It is one of the best shots I have seen on the net and really helps us newbies to see where all the parts are kept dry

Screw Loose

Thanks Solo, its not the clearest pic. I had to use my camera phone, forgot my real one. It all looks like an explosion in a spaghetti factory at the moment !

Screw Loose

Everythings in just about, and after a few minutes of sweating, I turned everything on and hey presto its working !

After installing my piston tanks, and re-wireing them I was a bit nervous about trying them again, but they work fine inside the hull. The same goes for the forward dive plane mechanism. I must admit it didnt work at first. But that was down to my servo (controling the forward planes) not closing the microswitch that actuates the motor properley. A quick modification with a screw head blanking plug, the ones in all our furniture, turned upside down with a screw inserted through the servo arm and onto the switch, and works well.





Speed controller is in, but not wired up yet. Need an extra connector. But motors wired up and ready to go. I am only going to use one speed controller, I know its supposed to use 2 but I have found on other subs that using 2 can be tricky to balence. Hard to get both props rotating at the same speed. Might just have been mine though!

And a new Robbe radio reciever is on its way. I use the Robbe F-16 computerised handset, with a campac module so I can use the same handset but store settings and trims for different boats.

So on with the re-wireing, it will be tidy sometime

Mankster

looking good, I hope you have a big puddle to play in, cos turning diameter with one ESC will be in the order of 25 feet on a good day