So i was talking with Dual twill , which by the way is a VERY helpful guy. great tips from him and i would never doubt his ways.
So i asked him, how are 2 parts sealed together. i did a search here and found nothing =. only things on sealant tape.
he suggested using a sealant that is in calking form, marine grade. bonds well for his apps. but what are others using.
i guess my method is the only way muahahaha
The two mouldings for my bike fuel tanks are bonded using polyester bonding paste (poly resin with filler added already), and over a period of nearly 3 years never had a single problem with this.
Guess if this works on something as critical as a fuel tank, it should be fine for most other applications.
Come on, spill the beans…
Would those techniques work for load bearing parts or would another technique be suggested for bonding together load bearing parts?
thats what im trying to figure out with the question =)
So far, i think a part such as a hood b/t the top hood and the bottom underside of the hood to put them together… i would consider a loading bearing part… no?
http://www.wicksaircraft.com/catalog/product_detail.php/pid=4715~subid=1334/index.html
and some tests with diff. types of bonding agents. take a look. its a good read
Polyester bonding paste works fine for secondary bonds used in the marine industry, so I think should probably be ok for cosmetic vehicle parts. Would be worth choosing epoxy if the part was going to be subject to high tempratures though I would think.
what about metal to composites?? Like i have poly cargo cover and need to mount moutning brackets. I have tried the poly paste but just a little force and they come right off
JB WELD does everything!
Have used JB weld to modify port shapes on cylinder heads, and it works fine!
JB weld in a port scares me…I use KOPCOAT…marine epoxy.
Its hard to get nowadays but when I hit it with a propane torch it burns slightly, gets soft and never lifts out of the port.
I used some other stuff and lost an engine due to it cracking out and hanging an intake valve up on me.
Belzona is a pretty good epoxy for ports too…so maybe thats a good bond agent?
The best way to modify a port is to TIG weld it with a pencil torch, but for low stress low rpm trials bike motors JB Weld works absolutely fine, but saying that we have used it on inlet ports of Suzuki GSXR motors with 195 bhp at the rear wheel.
i am watching this thread for good ideas
i have tried the filler in resin to bond top and bottom of hoods together problem i have had is that it shrinks and leaves a very wavy surface but it is a verry strong bond
have also used lords and plexus adhesives{$$$$} problem is if it gets a real good bond it leaves lines in the top others dont get a real good bond???
The loctite hysol brand adhesives seem like a good choice. Here’s another:
http://www.pliogripbyvalvoline.com/panel_bonding.html
http://www.pliogripbyvalvoline.com/smc_repair.html
http://www.compositesworld.com/ct/issues/2006/February/1182
BMW conducted extensive adhesive validation studies, including dynamic and static torsion tests, lap shear tests, dynamic mechanical analysis, peel tests, aging/climatic stress tests and an actual crash test, using different steel paints, surface prep methods and curing times. While phenolics, epoxies and acrylates were considered, the company selected PLIOGRIP, a two-part polyurethane manufactured by Ashland Specialty Polymers and Adhesives (Dublin, Ohio), which meets the structural performance requirements for bonds between dissimilar materials at service temperatures of 80°C/176°F (the highest the roof will see in hot, sunny weather) yet has sufficient elasticity (~50 percent elongation) to handle vibration loads.
Quite a few vehicle body panels are joined to monoques with 2 part PU adhesives…only problem with this is the cost of the material, and applicator system.
However for something like a car hood, single part PU I think would probably be perfectly ok, and is far cheaper, also no need for special applicator systems.
I think everyone uses something else. There are so many brands and kinds of adhesives.
We use Hysol (loctite) EA9394, EA956
Huntsman 9610 (et al) for core filler
and sometimes high-temp tooling epoxy IN parts!!
and of course I always like contact cement
if you are worried about your bond craking over time and separating you can either talk to you technical support from you resin company and ask them for a mixing ratio that will make the rein more flexible, making your mixture less britol, and using a combination of cabosil and hallow micro balloons. or you can buy a flex additive to make a 3part stsyem. also silicone bonds very well, but you cant paint it.