Does Epoxy stick to polyethylene?

[captain nemo12]

Hi guys,

I've seen people using plastic sheets to create that metal plating effect on their boats, and I thought about doing this myself. You see, I have found some transparent plastic sheets that's the perfect thickness for this kind of detailing. The plastic is pretty slippery to the touch and CA glue does a poor job holding it together, so I wonder if epoxy would do the trick. Will making the plastic rougher by sanding its surface help the epoxy stick better?

[bradv]

On the back of the

On the back of the packet of 5-minute epoxy adhesive (Araldite) I just bought it notes]http://www.subcommittee.com/forum/icon_sad.gif[/img]


I was similarly concerned about epoxy bonding to a nylon servo control arm which I'd heavily modified to be a miniature control horn (for my Kilo's rear dive planes) as nylon is also a fairly slippery plastic. I ended up using medium CyA instead for the sole reason that epoxy was too thick to squeeze into the tiny spaces between parts! Seems to have held well, though I did rough up the surfaces to help with this.

[Guest]

You may find this link

You may find this link useful-

http://www.deluxematerials.co.uk/system/index.html

Roughing up a material almost always helps the bond by providing a key for the material.

Andy

[wingtip]

plastistruct sells a glue that

plastistruct sells a glue that melds the plastics together just not adheres, it melt/melds them together..

Ambroid ProWeld
http://www.ambroid.com/Ambroid.html

[wingtip]

or you could try this


TENAX-7R
http://www.nscalesupply.com/TEN/TEN.html

or you could try this


TENAX-7R
http://www.nscalesupply.com/TEN/TEN.html

[raalst]

@Bradv
Do you have any pictures

@Bradv
Do you have any pictures we (I) can use as an inspiration ?
and I mean pictures of the Kilo

[bradv]

Here you go, Raalst]Bradv's SC

Here you go, Raalst]Bradv's SC homepage[/url]

I've just finished building the Kilo & case so have posted the piccies before its pool tests later today (bath-tub test passed fine at least).
A big thanks to our local sub-gurus, Jim & Cameron from MSSA, for all their help!

[raalst]

Nice !

I have looked a

Nice !

I have looked a bit at the WTC. where do you put the batteries ?
is it the black blob in the front ?

I'm still busy (snails pace) fitting it all in the WTC.
I will be using standard AA batteries (6 of 'em)

If your prop axle is fitted with a M3 (3mm) metric thread,
I could provide you with a 5 bladed screw.
one catch ]this dutch shop[/url]

Regards,
Ronald

[bradv]

Hi Raalst,

A quick rundown

Hi Raalst,

A quick rundown of what I used may be more helpful. From front to back]http://www.subcommittee.com/forum/icon_biggrin.gif[/img]

4. Fiago receiver (36MHz) - tiny!!

5. 2 x mini-servos (it's a dynamic diver).

6. SubTech APC-4 (on top). Again, nice & tiny.

7. Futaba MC230CR ESC (on bottom). Small & gives excellent performance in forwards, but as it's from a car which uses a braking mechanism, it has troubles going into reverse. Does include an BE/VR circuit which is nice, so I don't need an external circuit to drop the 7.2v down for the radio gear.

8. Graupner Speed140. This is a 280 geared down 2]http://www.subcommittee.com/forum/icon_wink.gif[/img] I'll be talking to our other local sub guru, Jim (from MSSA again) shortly about either a proper Graupner 20mm M2 3-bladed, or alternately casting a duplicate of the kit prop in extremely hard plastic (the screw onto the shaft may be problematic). Thanks for your suggestion though Raalst - sounds like a lovely prop, but the M2 shaft I'm using limits me a bit unfortunately.

12. I couldn't find a control horn small enough for the rear planes, so manufactured one out of a servo arm. Not having enough room in the tiny rear, I used an external linkage for the rudder, chopping down a standard elevator control horn to do the trick.

13. External aerial, but well sealed to prevent shorting to the water. I did this so I could get a larger loop and also move it a litle further away from the internal electronics.

14. The lights in the sail are red, green and white LED's, which use very little current and are pretty robust. Thats why I have the black wire connecting the WTC to the sail.

15. I went for only two, small aerials (brass rod) on the sail (duplicating a couple of photos I have of real Kilos) as I didn't want to bend or break a collection of larger ones at speed. Even with the smaller prop, it's top speed is still pretty quick, but those aerials aren't going anywhere

16. The upper & lower hulls are held together with rare earth magnets. The WTC is held in place with velcro.


My first pool test today was reasonable. With the smaller prop, it now goes slower so more ballast was needed for it to dive (suprise suprise). This has the added advantage of further reducing the torque roll so I'm happy with that. It also travels at a more scale speed now, which is nice. It responds well to controls, but probably needs just a little permanent down adjustment on the rear planes to help the APC keep it at depth. I used the stock control surfaces from the kit, but made them completely flying. The turning circle is about 2.5m, which isn't too bad, but could certainly be better. All in all, it's first run was reasonable and after a few minor mods I'm looking forward to it behaving itself better next time.





Edited By Bradv on 1142169213

[raalst]

thanks for the explanation !

Btw,

thanks for the explanation !

Btw, I was not aware that AA cells could produce H2 when charging (I use NiMH and I think you do too, judging on the
capacity).
I thought that H2 stuff was something for "real" (i.e. car)
batteries and comparable technology.

Regards,
Ronald

Ps I'll try posting my WTC as it is now. It has a syringe
ballast tank. and a motor in the wet.

[bradv]

Yup, they're NiMH batteries (from

Yup, they're NiMH batteries (from Jaycar Electronics).

Duracell's website has this to say about NiMH recharging]Vented Battery Compartments[/b]
It is possible that cells may vent if the battery is
overcharged or otherwise abused. Nickel-metal
hydride cells release hydrogen gas during venting
which could form potentially explosive mixtures
with air. Caution should be exercised to prevent
the gas from collecting in the battery or equipment.
Exposure to a source of ignition and airtight
device compartments should be avoided.

Something we'd all like to avoid in a submerged, confined (and expensive) space!


Out of interest, what's the capacity of the syringe you're using? Sounds like a cool way of ballasting!

[raalst]

max 25 ml = 25

max 25 ml = 25 grams. will see how far down I get her with that.
it's just to make dynamic diving a bit easier, i suspect.
I do not expect to reach negative buoyancy with this.

the syringe setup as such can be seen onMy Webpage.

Since I scared from the hydrogen, I did some reading up.
It seems they can produce hydrogen, but only when severely overcharging them or continuously trickle charging them.
If you use a NiMH charger with overcharging protection,
I think they behave well. but one can never be too cautious.



Edited By raalst on 1142095538

[raalst]

as promised,

a picture of

as promised,

a picture of my WTC

and a shameless plug for a dutch company which makes
what comes closest to a decent kilo prop ]picture of my prop[/url]

[bradv]

Both the prop & WTC

Both the prop & WTC look great The 5 blades on the prop is close enough to the 6-bladed one with the kit that, at that size, few will notice the difference. I found that just having the right-sized prop (2cm) makes a world of diferrence in both appearance and performance.

I look forward to seeing the complete WTC and ultimately the finished Kilo!