General adhesive and bonding questions

[pedro gomez]

Epoxy 5 minutes bond

My recommendation for my experience is: don't use epoxy 5 minutes in pressure hull joints. I dont'n know the reason. Will be the damp, chlorine, or other factors, but after time, years, it become soft and gummi, and lost their adherence.
7 years ago I had a flooding because a joint in my ballast tank become gummy and the pressure (2-3 m) made a big leak, in a swimming pool. The presure hull was flooded and thanks to a diver who was filming our submarines, I could recover it and save the majority of components.

[junglelord]

Dean,

Be careful where you use

Dean,

Be careful where you use JB Weld on that Moebius Seaview. I used it to bond the long seams on my Gato and found that if the hull flexed (which your resin model likely wouldn't have done) the JB Weld had a tendency to crack. As Steve mentioned above, for styrene to styrene bonding you can't beat using a solvent welder such as Ambroid Pro Weld, which literally fuses the plastic together into a single piece. The resulting joint is as strong as or stronger than the original material.

I do use some JB Weld in places on my Seaview, but only as a seam filler after the bond has been made with the Ambroid. JB Weld works best as a primary bonder where there is a good amount of contact area, with no flexing.

Do you have a store that you got that from?
I have to call the Ottawa Hobby shops soon, but I have not found that item locally. I could always have it sent by the manufactuer.
Thanks Ivan.

[crazy ivan]

We have a local hobby

We have a local hobby shop, Dan's Crafts & Things, that carries it. They do sell through their website as well if you wanted to order from them.

http://www.danscraftsandthings.com/

[Larry Kuntz]

Hey guys,
Plastruct Bondene Solvent Cement

Hey guys,
Plastruct Bondene Solvent Cement is the same thing I believe. I see it in lots of on-line hobby sites, including Tower Hobbies. Unfortunately TH only sells in in a case 10 pack. Everyone else sells single bottles. I use a pipet, kind of an eyedropper without the rubber bulb, to apply it. The capillary action pulls up a small amount, then just touch it to the joint and it wicks in instantly. Hold the pieces for a few seconds and your done. Works great with a minimal amount of practice. (And I need all the practice I can get)

[crazy ivan]

Hey guys,
Plastruct Bondene Solvent Cement

Hey guys,
Plastruct Bondene Solvent Cement is the same thing I believe. I see it in lots of on-line hobby sites, including Tower Hobbies. Unfortunately TH only sells in in a case 10 pack. Everyone else sells single bottles.

Yeah, Dan's has the Bondene too. It's about a buck cheaper than than the Ambroid in the 2 oz. bottle. I don't know why the difference. Then they also carry Tenax 7R. Similar price, but for only 1oz. Remind me to ask BD if he ever compared the three. After all, they're all solvent welders.

[kazzer]

Some time ago, I prepared

Some time ago, I prepared a report on different bonding materials to use on certain substrates and you can download it here.

http://support.caswellplating.com/index.php?_m=downloads&_a=viewdownload&downloaditemid=75&nav=0,5

To summarise it, using epoxies on thermoplastics like the injection molded products is really second best. You are much better off using a solvent weld material. This material actually liquefies the plastic, then evaporates, allowing it to fuse together. It is a true weld. Epoxies in this situation, do not bond as well. You can make your own filler material using sprue and solvent. see here -

http://forum.sub-driver.com/showthread.php?t=299

These solvents will not work on anything other than thermoplastics, so if you need to bond a thermoplastic to an epoxy part, or fiberglass (polyester), or metal, then the epoxy will work well.

Solvent welding products usually contain methylene chloride, found in most good paint strippers. and so you could use that. Its much cheaper than those little bottles. Get the one that is liquid, not gel.

CA (Superglue) is ok on small areas, but it is brittle and doesn't like shock stresses on the bond.

I'd suggest you use the slower epoxies with a simple mix ratio. I sell a Ciba Geigy (Araldite) Phenol Novolac resin in small quantities, 2]http://www.caswellplating.com/aids/epoxygas.htm[/url]

http://www.caswellplating.com/aids/images/gtsbox.jpg

My favorite material for doing work on fiberglass hulls is Quickwood, a 5 minute working life, 30 minute full cure. Totally immersible, and comes in a Tootsie roll style. Just cut off what you need and mix by rolling in your fingers. The putty can be pressed into holes etc and smoothed off with a wet knife or finger.
see

http://www.caswellplating.com/aids/quikwood.htm

http://www.caswellplating.com/aids/imag ... d7inch.jpg