Site Navigation

Your Account

Choose Language

Guide 2 - Battery and Main Tube Endcaps

This guide will walk you through the steps to create the two battery tube endcaps and the main electronics tube endcaps.

  • Author: OpenROV
  • Time estimate: 1 hour
  • Difficulty: Moderate

You should have a good understanding of how acrylic cement works at this point. We are now going to introduce the use of epoxy. The epoxy acts as a barrier to the water and allows wires to "pass through" the endcaps.

Edit Step 1 Battery Tube Endcaps  ¶ 

Image 1/2: Start by removing the paper backing. Image 2/2: Start by removing the paper backing.

Edit Step 1 Battery Tube Endcaps  ¶ 

  • There are 8 acrylic parts needed to make the battery tube endcaps.

  • Start by removing the paper backing.

Edit Step 2  ¶ 

Image 1/2: Place the first piece onto the threaded rod as shown. Image 2/2: Place the first piece onto the threaded rod as shown.

Edit Step 2  ¶ 

  • To keep the parts aligned we are going to use the threaded rod on the motors. Take one of them out and remove the hardware (nuts and washers) from the threaded rod. Set these aside for later.

  • Place the first piece onto the threaded rod as shown.

2 Edit Step 3  ¶ 

Image 1/3: Place the second piece, one of the thinner disks, onto the first as shown. Image 2/3: Apply acrylic cement. Image 3/3: Place the third piece, the small thick disc, and cement it in place as shown.

2 Edit Step 3  ¶ 

  • When working with acrylic cement it is recommended that you wear gloves, safety glasses, and work in a ventilated area.

  • Place the second piece, one of the thinner disks, onto the first as shown.

  • Apply acrylic cement.

  • Place the third piece, the small thick disc, and cement it in place as shown.

  • Place the fourth piece, another thin disk, and cement it in place as shown.

Edit Step 4  ¶ 

Image 1/1: After the acrylic cement has cured (about 10 minutes) you can remove them from the motors.

Edit Step 4  ¶ 

  • Use a second motor to repeat the process while the first endcap is curing.

  • After the acrylic cement has cured (about 10 minutes) you can remove them from the motors.

  • Place the endcaps and the motors aside, as we won't need them again for a while.

2 Edit Step 5 Syringe  ¶ 

Image 1/2: Remove the plungers from both syringes -- we're going to cut the syringe tubes in two locations. Image 2/2: Make sure to set aside the plungers in a safe place as they're needed to seal the electronics tube.

2 Edit Step 5 Syringe  ¶ 

  • Next we will modify the two syringes. This process is identical for both syringes.

  • Remove the plungers from both syringes -- we're going to cut the syringe tubes in two locations.

  • Make sure to set aside the plungers in a safe place as they're needed to seal the electronics tube.

2 Edit Step 6  ¶ 

Image 1/3: Be careful not to cut this too short. The plunger should stop where it usually does when inserted. Image 2/3: Then cut at the 0.16 mL mark, as shown. Image 3/3: Then cut at the 0.16 mL mark, as shown.

2 Edit Step 6  ¶ 

  • Cut the syringe tubes with a thin hacksaw blade above the plunger stopping point, as shown.

  • Be careful not to cut this too short. The plunger should stop where it usually does when inserted.

  • Then cut at the 0.16 mL mark, as shown.

Edit Step 7  ¶ 

Image 1/1:

Edit Step 7  ¶ 

  • Use medium grit sandpaper to smooth the edges and square them up.

Edit Step 8  ¶ 

Image 1/3: Make sure to be careful with the razor as it is sharp. Image 2/3: Remove any grit or dust left inside. Image 3/3: You can use compressed air or a Q-tip wetted with water or alcohol to clean the inside of the syringe section.

Edit Step 8  ¶ 

  • Using a razor, carefully debur the inside edge of the syringe section, but be careful not to make any large gashes along the inside surface!

  • Make sure to be careful with the razor as it is sharp.

  • Remove any grit or dust left inside.

  • You can use compressed air or a Q-tip wetted with water or alcohol to clean the inside of the syringe section.

  • You should now have two syringe sections.

Edit Step 9  ¶ 

Image 1/1: The main tube endcaps are the most important part of the OpenROV as they keep your electronics dry.

Edit Step 9  ¶ 

  • We're going to assemble the endcaps for the main tube in the next steps. There are two endcaps (port and starboard) and they are not identical.

  • The main tube endcaps are the most important part of the OpenROV as they keep your electronics dry.

  • Pay close attention to the instructions. There are 4, 1.5mm flanges, 2 are clear and 2 are white - make sure you know which one you need.

Edit Step 10  ¶ 

Image 1/1: If they are dirty or dusty clean them with a soft cloth.

Edit Step 10  ¶ 

  • Keep the parts in the following steps clean. Remove the backing right before cementing them together.

  • If they are dirty or dusty clean them with a soft cloth.

Edit Step 11  ¶ 

Image 1/2: We're going to begin with the 3mm thick disc. This one is slightly larger in diameter than the similar-shaped 6mm thick disc. Image 2/2: We're going to begin with the 3mm thick disc. This one is slightly larger in diameter than the similar-shaped 6mm thick disc.

Edit Step 11  ¶ 

  • For these directions we have outlined each part with a white ring.

  • We're going to begin with the 3mm thick disc. This one is slightly larger in diameter than the similar-shaped 6mm thick disc.

Edit Step 12  ¶ 

Image 1/1:

Edit Step 12  ¶ 

  • Next insert the cut syringe face down into the center hole as shown.

Edit Step 13  ¶ 

Image 1/1:

Edit Step 13  ¶ 

  • Next, stack the 6mm thick disc on top. Make sure to line up the holes as shown.

Edit Step 14  ¶ 

Image 1/2: Notice that the syringe is flush with the surface of the 3mm circle. Try to maintain this throughout the next few steps. Image 2/2: Notice that the syringe is flush with the surface of the 3mm circle. Try to maintain this throughout the next few steps.

Edit Step 14  ¶ 

  • Pick up the pair and turn it over.

  • Notice that the syringe is flush with the surface of the 3mm circle. Try to maintain this throughout the next few steps.

3 Edit Step 15  ¶ 

Image 1/3: While holding one side, place the needle of the applicator between the two surfaces to be cemented. Image 2/3: Add a liberal amount of cement. The goal is to have cement completely filling the gap between the surfaces. Any excess or spills will evaporate quickly or can be wiped away. Image 3/3: Apply slight pressure with both hands while the cement cures.

3 Edit Step 15  ¶ 

  • The best method of cementing the endcap parts together is as follows:

    • While holding one side, place the needle of the applicator between the two surfaces to be cemented.

    • Add a liberal amount of cement. The goal is to have cement completely filling the gap between the surfaces. Any excess or spills will evaporate quickly or can be wiped away.

    • Apply slight pressure with both hands while the cement cures.

Edit Step 16  ¶ 

Image 1/1: Clean any excess off with a paper towel or cloth.

Edit Step 16  ¶ 

  • Add acrylic cement around the entire edge of the newly cemented parts to ensure that they are completely joined.

  • Clean any excess off with a paper towel or cloth.

Edit Step 17  ¶ 

Image 1/1:

Edit Step 17  ¶ 

  • Make sure that the syringe is still flush with the surface of the 3mm disc.

Edit Step 18  ¶ 

Image 1/1:

Edit Step 18  ¶ 

  • Add some acrylic cement to the gap between the discs and the syringe.

Edit Step 19  ¶ 

Image 1/3: Keep the two circles concentric as indicated. Image 2/3: Cement this new part to the other discs using the same procedure as before. Image 3/3: Cement this new part to the other discs using the same procedure as before.

Edit Step 19  ¶ 

  • Add the thin 1.5mm flange with the three circles to the top of the 6mm thick disc. Make sure to orient it exactly as shown.

  • Keep the two circles concentric as indicated.

  • Cement this new part to the other discs using the same procedure as before.

Edit Step 20  ¶ 

Image 1/3: Keep them lined up as shown. Image 2/3: Again cement these together using the same technique as before. Image 3/3: Again cement these together using the same technique as before.

Edit Step 20  ¶ 

  • Next, add the 6mm flange to the top of the piece you just added.

  • Keep them lined up as shown.

  • Again cement these together using the same technique as before.

Edit Step 21  ¶ 

Image 1/3: Make sure that they remain concentric. Image 2/3: Cement them completely using the same technique as before. Image 3/3: Set this completed endcap aside to cure.

Edit Step 21  ¶ 

  • Now add the 1.5mm WHITE flange to the top as shown. There is only the center hole.

  • Make sure that they remain concentric.

  • Cement them completely using the same technique as before.

  • Set this completed endcap aside to cure.

Edit Step 22  ¶ 

Image 1/1:

Edit Step 22  ¶ 

  • Next start the second endcap with the 3mm disc as before.

Edit Step 23  ¶ 

Image 1/1:

Edit Step 23  ¶ 

  • Add the syringe as shown.

Edit Step 24  ¶ 

Image 1/1: Keep the holes lined up just as before.

Edit Step 24  ¶ 

  • Add the 6mm disc to the top as before.

  • Keep the holes lined up just as before.

Edit Step 25  ¶ 

Image 1/2: Keep in mind to have complete coverage with the cement. Image 2/2: Keep the syringe flush with the surface of the 3mm disc.

Edit Step 25  ¶ 

  • Cement these parts just as before.

  • Keep in mind to have complete coverage with the cement.

  • Keep the syringe flush with the surface of the 3mm disc.

Edit Step 26  ¶ 

Image 1/2: Cement them together using the same technique as before. Image 2/2: Be careful to keep the circles concentric and lined up while cementing.

Edit Step 26  ¶ 

  • Add the thin 1.5mm flange with the three circles exactly as shown. The orientation is very important.

  • Cement them together using the same technique as before.

  • Be careful to keep the circles concentric and lined up while cementing.

Edit Step 27  ¶ 

Image 1/2: Line up the holes as shown. Image 2/2: Cement using the same technique as before.

Edit Step 27  ¶ 

  • Add the 6mm flange to the top.

  • Line up the holes as shown.

  • Cement using the same technique as before.

  • Stop here. Do not add the white flange.

1 Edit Step 28  ¶ 

Image 1/1: Make sure yours look just as the ones in the picture.

1 Edit Step 28  ¶ 

  • At this point you should have two completed endcaps.

  • Make sure yours look just as the ones in the picture.

1 Edit Step 29  ¶ 

Image 1/3: Cut between the cut end of the syringe but below the plane of the endcap as shown. Image 2/3: Remove the plunger and set aside in a clean place for later. Image 3/3: Keep both parts of the syringe plunger.

1 Edit Step 29  ¶ 

  • Next place the syringe plunger into the endcap.

  • Cut between the cut end of the syringe but below the plane of the endcap as shown.

  • Remove the plunger and set aside in a clean place for later.

  • Keep both parts of the syringe plunger.

  • Do this for both syringe/plunger combos.

Edit Step 30 Debur Electronics Tube  ¶ 

Image 1/2: Bevel the inner edges of the main tube using a medium grit sandpaper so that the o-ring will fit in the tube without getting damaged by the sharpness of the tube's inner edge. Image 2/2: Wipe off all the dust left over from the sanding process when done.

Edit Step 30 Debur Electronics Tube  ¶ 

  • Now we'll make sure the endcap fits correctly in the Main Tube.

  • Bevel the inner edges of the main tube using a medium grit sandpaper so that the o-ring will fit in the tube without getting damaged by the sharpness of the tube's inner edge.

  • Wipe off all the dust left over from the sanding process when done.

  • DO NOT SAND THE INNER SURFACE OF THE TUBE WHERE THE O-RING WILL BE. This part must be kept completely smooth; only chamfer the edge.

  • Make sure to do this for both ends.

Edit Step 31 O-ring test fit  ¶ 

Image 1/3: Since the o-ring will make a pretty tight fit with the main tube, it is recommended that a lubricant be used. Image 2/3: We like to use a common lubricant called "MagicLube" which is available at many hardware stores. Image 3/3: To apply the lubrication to the o-ring, squeeze a small amount of lubrication onto your finger and then move the o-ring through your fingers.

Edit Step 31 O-ring test fit  ¶ 

  • Place a #340 o-ring (the large size) in the grooves ("o-ring glands") of both endcaps.

  • Since the o-ring will make a pretty tight fit with the main tube, it is recommended that a lubricant be used.

  • We like to use a common lubricant called "MagicLube" which is available at many hardware stores.

  • To apply the lubrication to the o-ring, squeeze a small amount of lubrication onto your finger and then move the o-ring through your fingers.

  • When using lubrication it is recommended that you wear gloves.

Edit Step 32 Test Fit of O-Rings and Tube  ¶ 

Image 1/2: VERY IMPORTANT: Because the tolerances of the pieces may vary slightly, it's possible that your endcap may not engage tightly enough with the main tube. (You can see an example of what this looks like in the second image). Image 2/2: If the endcap doesn't fit well, the band of engaged o-ring will be very thin or may even disappear in spots. If this is the case or if you have any other issues please [https://docs.google.com/forms/d/1erC38nIh78S734N2UQK6Xx3VYgYXOvShA9TQ25Pyzs0/viewform?fbzx=329119282362925793|contact us|new_window=true].

Edit Step 32 Test Fit of O-Rings and Tube  ¶ 

  • Place the endcap into the main tube and inspect to make sure that at least a 1mm-thick band of the o-ring is pressed against the inside of the main tube. Rotate the tube to make sure the o-rig engages along the entire interior perimeter of the tube.

  • VERY IMPORTANT: Because the tolerances of the pieces may vary slightly, it's possible that your endcap may not engage tightly enough with the main tube. (You can see an example of what this looks like in the second image).

  • If the endcap doesn't fit well, the band of engaged o-ring will be very thin or may even disappear in spots. If this is the case or if you have any other issues please contact us.

  • If the endcap tends to pop off on its own, it means you need to chamfer the inner edge of the tube a little more.

2 Edit Step 33  ¶ 

Image 1/3: A good way to remove the o-rings is to squeeze the o-ring so there's a gap and stick the discarded end of the plunger from the previous steps. [Thanks to Petter for this suggestion!]. Image 2/3: Be careful not to damage the o-ring. Image 3/3: Be careful not to damage the o-ring.

2 Edit Step 33  ¶ 

  • Remove the o-rings and put them in a safe, clean place until ready for use.

  • A good way to remove the o-rings is to squeeze the o-ring so there's a gap and stick the discarded end of the plunger from the previous steps. [Thanks to Petter for this suggestion!].

  • Be careful not to damage the o-ring.

Edit Step 34  ¶ 

Image 1/1:

Edit Step 34  ¶ 

  • Pick up this endcap. This is the port endcap and the endcap through which the wire harness is potted.

Edit Step 35 Twisting DB-25 Wires  ¶ 

Image 1/3: Pins 14-17 are the IMU wires: power positive (red stripe), data SCL (green stripe), data SCA (white stripe), power negative (black stripe). Image 2/3: Pins 18-19 are the tether wires (solid yellow). Image 3/3: Using your hands begin twisting the two tether wires at the base of the DB-25. Continue twisting to the end of the wires.

Edit Step 35 Twisting DB-25 Wires  ¶ 

  • Begin by separating the wires on pins 14-19 on the DB-25.

    • Pins 14-17 are the IMU wires: power positive (red stripe), data SCL (green stripe), data SCA (white stripe), power negative (black stripe).

    • Pins 18-19 are the tether wires (solid yellow).

  • Using your hands begin twisting the two tether wires at the base of the DB-25. Continue twisting to the end of the wires.

  • Be careful not to twist with too much force or by pulling the wires too hard. The wires may break from the connector if care is not taken.

  • Use the same technique for the IMU wires. Be sure to pair:

    • Power positive (red stripe) and data SCL (green stripe).

    • Power negative (black stripe) and data SCA (white stripe).

Edit Step 36  ¶ 

Image 1/3: For the rest of this guide the wires in the photos will not be twisted. Your wires '''should''' be twisted. Image 2/3: For the rest of this guide the wires in the photos will not be twisted. Your wires '''should''' be twisted. Image 3/3: For the rest of this guide the wires in the photos will not be twisted. Your wires '''should''' be twisted.

Edit Step 36  ¶ 

  • The finished DB-25 connector should look like the photos to the left.

  • For the rest of this guide the wires in the photos will not be twisted. Your wires should be twisted.

Edit Step 37 Endcap Wiring  ¶ 

Image 1/2: Careful pulling wires through the hole. The edges of the acrylic can slowly strip off the insulation of the wires if scraped against it. Image 2/2: Careful pulling wires through the hole. The edges of the acrylic can slowly strip off the insulation of the wires if scraped against it.

Edit Step 37 Endcap Wiring  ¶ 

  • You're now ready to add wiring to the port endcap. Thread the DB25 cable through the endcap as shown.

  • Careful pulling wires through the hole. The edges of the acrylic can slowly strip off the insulation of the wires if scraped against it.

3 Edit Step 38  ¶ 

Image 1/2: Double-check this measurement as will be made permanent in the next step. If it is too short you won't be able to plug it into the circuit board. If it's too long it could push on the other endcap. Keep it between 16.5cm and 17.5cm. Image 2/2: Double-check this measurement as will be made permanent in the next step. If it is too short you won't be able to plug it into the circuit board. If it's too long it could push on the other endcap. Keep it between 16.5cm and 17.5cm.

3 Edit Step 38  ¶ 

  • Measure 17cm from the top surface of the endcap to the top of the DB-25 connector (it should be bent at 90 degrees) for this measurement.

  • Double-check this measurement as will be made permanent in the next step. If it is too short you won't be able to plug it into the circuit board. If it's too long it could push on the other endcap. Keep it between 16.5cm and 17.5cm.

Edit Step 39  ¶ 

Image 1/1:

Edit Step 39  ¶ 

  • The connector of the DB-25 should be facing away from the flat side of the endcap.

Edit Step 40  ¶ 

Image 1/3: Keep the wire harness from moving too much from the 17 cm measurement. Image 2/3: Make sure the bundle lies flat on the outside surface of the endcap. Use your thumb to massage the wire in place. Image 3/3: When working with acrylic cement it is recommended that you wear gloves, safety glasses, and work in a ventilated area.

Edit Step 40  ¶ 

  • Put on some gloves and prepare the acrylic cement.

  • Keep the wire harness from moving too much from the 17 cm measurement.

  • Make sure the bundle lies flat on the outside surface of the endcap. Use your thumb to massage the wire in place.

  • When working with acrylic cement it is recommended that you wear gloves, safety glasses, and work in a ventilated area.

Edit Step 41  ¶ 

Image 1/3: Place the white endcap accent piece flat against the outside of the endcap. Image 2/3: This should be held firm as the wire bundle can push up and create a gap. Image 3/3: Apply acryilc cement around all edges and center circle and allow to cure.

Edit Step 41  ¶ 

  • Take off backing for remaining white acrylic piece.

  • Place the white endcap accent piece flat against the outside of the endcap.

  • This should be held firm as the wire bundle can push up and create a gap.

  • Apply acryilc cement around all edges and center circle and allow to cure.

7 Edit Step 42  ¶ 

Image 1/2: Wear gloves when handling epoxy and have paper towels on hand to clean any surfaces that it happens to drip on. Image 2/2: Find the starboard endcap (the one without the wire bundle) and place a piece of tape over the bottom hole. Make sure it is sealed.

7 Edit Step 42  ¶ 

  • It's time to start the potting. Grab the 2-ton epoxy.

  • Wear gloves when handling epoxy and have paper towels on hand to clean any surfaces that it happens to drip on.

  • Find the starboard endcap (the one without the wire bundle) and place a piece of tape over the bottom hole. Make sure it is sealed.

  • Remove the 2-ton epoxy from the packaging and affix the mixing tube to the end of the syringes.

  • From the top hole, begin filling it in with epoxy.

  • Tilt the end cap towards you and fill the hole starting from the bottom. This will push out any air trapped in the back out from the top.

  • After a few minutes (once the epoxy has settled), check and see if you need to add any more epoxy to fill the hole to the top.

Edit Step 43  ¶ 

Image 1/2: Get the white polypropylene shell and set it next to your endcap as shown. Tape the bundles so they stay in place and drape the wires over the frame to keep them held vertically. Image 2/2: Get the white polypropylene shell and set it next to your endcap as shown. Tape the bundles so they stay in place and drape the wires over the frame to keep them held vertically.

Edit Step 43  ¶ 

  • These steps cannot be undone so double check that there is exactly 17 cm from the inside of the port endcap to the top of the bent DB-25 connector.

  • Get the white polypropylene shell and set it next to your endcap as shown. Tape the bundles so they stay in place and drape the wires over the frame to keep them held vertically.

1 Edit Step 44  ¶ 

Image 1/3: Since the epoxy will be acting as a barrier between the water and your electronics it is important that epoxy surround and fill all the air gaps. To ensure that this happens, move the wires gently around and spread them apart and back together. Image 2/3: Fill the bottom of the two holes and repeat the movements. Image 3/3: Refill the top hole again unless it is already all the way full.

1 Edit Step 44  ¶ 

  • Firmly and evenly squeeze epoxy out into the taller of the holes.

  • Since the epoxy will be acting as a barrier between the water and your electronics it is important that epoxy surround and fill all the air gaps. To ensure that this happens, move the wires gently around and spread them apart and back together.

  • Fill the bottom of the two holes and repeat the movements.

  • Refill the top hole again unless it is already all the way full.

Edit Step 45  ¶ 

Image 1/1: After a few minutes, see if you need to add any more epoxy. Use a paper towel to remove excess epoxy before it cures.

Edit Step 45  ¶ 

  • It's very important not to let any epoxy cure in the area shown in the picture. This is the o-ring gland and needs to make a good seal with both the o-ring and your electronics tube.

  • After a few minutes, see if you need to add any more epoxy. Use a paper towel to remove excess epoxy before it cures.

  • Let the epoxy cure for 4-6 hours.

Edit Step 46  ¶ 

Image 1/1:

Edit Step 46  ¶ 

  • Once here, you can move on. We are done with the endcaps for now. Epoxy still needs to be added around the syringe, but this will be completed in guide 5.

Edit Step 47  ¶ 

Image 1/1:

Edit Step 47  ¶ 

  • Continue your build by progressing to Guide 3.

You're Done!

24 Comments

Living in Sweden I never managed to import the recommended acrylic cement. Instead, (after spending quite some time looking) I got hold of "Acrifix 1S 0117". Acrifix comes in different varieties. 117 is the most watery and the one required for OpenROV assembly. The smallest volume I could get was 1 kg(!) and I have plenty left. Contact me if you need some.

I also ended up using syringes with a thin needle to apply the cement instead of the applicator. Works very well.

The 2-ton epoxy flow mix was also not available in Sweden. The problem is to ge an Epoxy that is slow enough to allow for potting. Whats in most stores in Sweden is far too quick. Finally I got hold of "Casco Strong Epoxy Professional" with a couple of hours time to cure. I mixed the Epoxy thoroughly and used a syringe (without the needle) to apply it.

Thomas Dahlgren - Reply

This is fantastic information! It would be great if you also posted this on the forum so more people can learn where to find the solvents and epoxies.

https://forum.openrov.com/t/finding-acry...

Thanks,

-Brian G.

OpenROV -

there isn't syringes provided in the box. The syringe is included inside the box or I have to buy myself?

Chan Wai Yang - Reply

If you are missing anything please contact the support team here:

https://openrov.zendesk.com/hc/en-us/req...

Zack -

I used a small pipe cutting tool to cut the syringe tubes. This is very precise and leaves a very finished edge.

Kirk Lingenfelter - Reply

Kirk - Thanks for the great idea!

OpenROV -

Oh dear. Now I didn't have enough acrylic cement to fill the space between the two end caps, so I didn't seal them - kept them separate but there are rough streaks where the glue fell. I know the rough texture is not good for acrylic cement. What should I do?

Grace - Reply

Grace - It depends on which pieces the rough streaks are on. Can you send some pictures of them to us? support@openrov.com - Brian G.

OpenROV -

I also had trouble with this step. When you are doing this for the first time it is hard to know how much cement to apply. Filling about a third of the gap, while the needle is in the gap, turned out insufficient. It was then very hard to wick additional cement in to fill the gaps.

Filling two thirds of the gap was then too much. Cement squeezed out and started to melt my gloves :) I also then slightly damaged the underneath surface of the 6mm thick piece, which is now covered with the white layer.

I can see that with practice, this is not too hard, but its tricky to get it right the very first time. Perhaps the kit should include some additional large round pieces that are glued first, just to get the technique right. Just a thought.

Chris Thompson - Reply

Oh, I think I paste the flanges in the wrong direction... Is there any solution for this?

smsas - Reply

Reading ahead, guide 6 - step 27 also tells you to cut the syringe plungers. This time it tells you to cut them flush with the white plastic end. I cut them just below, as step 29 tells you to. Hopefully both approaches are fine?

Chris Thompson - Reply

An even safer way to remove the O rings is to use the rest of the syringe, the "handle" of the dube to lift the Oring out from the groove.

Petter F Schmedling - Reply

Hack of the month award! Thanks Petter! We will try this out in the lab and post it up if it works consistently. Amazing!

Zack -

I'm in Guide 5 now, and the connecter is 17cm long but doesn't seem to reach the board properly :/

Grace - Reply

Op no it's my fault; it's not really 17cm long. What should I do now...

Grace -

Ok I think it works by flipping the camera piece around; yay. Just talking to myself here...

Grace -

I know it seems obvious (now) but we should probably note that the tape SHOULD NOT BE REMOVED until the glue is dry. The glue does not stick to the tap. Oh, and don't do this step late at night after a long day at work. You can add that to most of the instructions :)

Chris Thompson - Reply

Good tip! Thanks.

Zack -

Hi there fellow Submariners!

Just a quick question about the potting stage using free flow epoxy resin.

Ive got just standard waterproof epoxy.. its a 2 plunger system but has to be premixed and then pasted with a stick rather than being injected via a plunger.

Is is acceptable to paste in this epoxy from both sides of the orifice??

Also wouldn't silicone sealant suffice (this is readily available in a trigger gun powered cartridge??)

This should easily flow around wires etc..

Also I am considering adding an additional set of sensors to measure temperature and water salinity etc.. should I consider adding additional wires through the orifice prior to potting it??

Appreciate any advice anyone may have!!

Many thanks and cheers!!

Paolo

bounceyball - Reply

Hey Paolo,

Yeah, I can safely say that you need an epoxy that has an applicator nozzle. It is necessary for the battery tubes and very helpful for the main tube endcaps. As far as silicone and other two-part materials, we've only tested the epoxy in the lab so I cannot guarantee that anything else will work. Silicone, depending on it's hardness may work but I'd be hesitant to use anything that is very soft.

Regarding sensors, we love this idea, but the proper place for that discussion is on our forums. I've seen a few good threads already about that sort of thing. Check it out here: https://forum.openrov.com/

~Zack

Zack -

Hi Zack, I trying to find 2 ton Epoxy flow mix or similar in my country, I've found one similar but the handling time is 10 minutes what is not recommendable . My question is if possible to use Epoxy Resins also called liquid glass, mixed into a syringe to fill the gaps. Many thanks !! Marco

neuquensub - Reply

I think a 10 minute working time should work. Just prepare ahead of time and you should be fine. I'm not sure whether the liquid glass has the right characteristics, but I do think most epoxies will do the trick.

What country are you in?

~Z

Zack -

Many thanks Zack !! I'l try this 10 min Epoxy. I'm in Argentina..

neuquensub - Reply

It is a good idea here to push the wire bundle as far back against the hole as possible (closer to the flat side of the end cap) to allow maximum room for your electrical chassis. I learned the hard way--if the wire bundle is bulging too far out toward the center of the endcap, you will not be able to get your camera to be level once it is in the tube.

Georgia Bennett - Reply