Bonding dissimilar plastics?

[StolenFox]

I am building a custom overhead gauge panel and I need to bond together two dissimilar plastics. The black gauge pods themselves are ABS plastic and the panel they will be attached to what I believe is glass fiber reinforced polycarbonate as evident by the “PC + GF” marking.

Can you folks recommend the right product for the job? Any recommendations would be appreciated!

S.F.

 

[EdT]

How good is the fit-up?

 

[bonneyman]

Plastic Welder. Two part epoxy-like material that works freaking great on the several types of plastic materials I've tried it on.

https://www.amazon.com/dp/B003NUGL9S/?tag=atomicindus08-20

 

[Bacon!]

We'd need more specifics. Maybe pictures of the gauges too. Surely they have some mount method intended? They have to, normally gauges are not *glued*/bonded into a vehicle.

Maybe just friction fit by heating the polycarbonate and press-fit or are they too fragile to handle tension?

It would be easy to say epoxy, but this limits the ease to change or repair the assembly later. Possibly mount a retention plate on whichever side they slip in from using screws?

 

[ilovevocs]

3m 4240. I'm fairly certain it covers your application. You can easily verify through the data sheet.

You don't need the gun, just open the cartilage and mix like you would any other epoxy.

 

[theoldwizard1]

3m 4240. I'm fairly certain it covers your application. You can easily verify through the data sheet.

Interesting and expensive stuff !

Scuff the surfaces with some sandpaper and wipe clean.

 

[Bacon!]

^ Yes very expensive when for this application a $2 tube of construction adhesive would work. Then again the price is not so different per oz than many other epoxies but the only real need for epoxy on this is if the polycarb panel is transparent so it's beneficial cosmetically to have a translucent bond.

In some ways it may be worse in that construction adhesive you can usually cut away with a utility knife while with epoxy you might destroy the gauges trying to get them out.

 

[StolenFox]

How good is the fit-up?

Fit is good and I can sand the ABS bezels to minimize any gaps between them and the polycarbonate plate.

Plastic Welder. Two part epoxy-like material that works freaking great on the several types of plastic materials I've tried it on.

https://www.amazon.com/dp/B003NUGL9S/?tag=atomicindus08-20

That looks promising. Amazon reviews are good, the only catch is the product must be fresh or it doesn't work.

We'd need more specifics. Maybe pictures of the gauges too. Surely they have some mount method intended? They have to, normally gauges are not *glued*/bonded into a vehicle.

Maybe just friction fit by heating the polycarbonate and press-fit or are they too fragile to handle tension?

It would be easy to say epoxy, but this limits the ease to change or repair the assembly later. Possibly mount a retention plate on whichever side they slip in from using screws?

I have pictures but photobucket won't host them anymore.... To be clear, I'm not trying to glue the gauges themselves into or on a panel. I'm trying to bond some gauge mounts to a a panel that is part of a console in the headliner. I bought a universal A-pillar gauge pod to cut the mounting pods off and use them to make the custom overhead mount.

3m 4240. I'm fairly certain it covers your application. You can easily verify through the data sheet.

You don't need the gun, just open the cartilage and mix like you would any other epoxy.

I will definitely look into that as well.

Thanks to all!

S.F.

 

[dogdog]

I thought they have those ultrasonic welders .....

 

[Bacon!]

You can upload the pictures elsewhere like www.imgur.com

The specifics could make a lot of difference. I'm wondering why normal fasteners won't work, or fab some kind of adapter bracket which you may be doing anyway.

Generally, bonding plastics with epoxy/etc requires a relatively large surface area. The smaller the contact area the more I'd drift towards bolts and load spreading plates or custom brackets as needed.

 

[CJ7VFR]

I have pictures but photobucket won't host them anymore....

Thanks to all!

S.F.

You don't need to have the pictures uploaded to an outside server to include them in your posts.

You can upload your pictures directly from your computer by clicking the "Manage Attachments" tab in the Additional Options window that is located below where you type in your replies and messages.

You hit the manage attachments tab and from there you click on any of the "browse" tabs so you can go to the location of the pictures on your computer. Once you locate the pictures you want to add, you click on the picture and when it shows up in the "browse" tab you click the "upload" tab that is located at the bottom of the browse tabs and the pictures will be added to your post. They will show up in your message as thumbnails, but they will expand into larger pictures when people click on the thumbnails.

Here is an example of a picture I copied from someone else's post a while ago so you can see how it works.

There is a maximum of 6 pictures to a post or reply doing it this way, so if you wanted to add more than that you would have to add them in more than one post.

Jim

 

[StolenFox]

Thank you for explaining the photo upload process. Here’s a couple of pics:

S.F.

 

[Bacon!]

Is there a limit on the image resolution that the built in image feature can handle? Those, they are "so big".

What are we seeing in the pics? Two gauges sitting on a skid looking piece. Is the skid piece going to be flipped over and mounted overhead and the gauges are sitting on it relatively where they're to be mounted?

If so it might be good to see the bottoms of the gauges (with pic resolution about an order of magnitude larger). Depending on how thick that skid piece is, not only might it flex too much for a good bond with epoxy, it might need washers on the back to use fasteners into the gauge housings.

Whether the gauge housing has a good area to get good purchase with a fastener is another issue but there has to be some way the manufacturer intended them to be mounted, something structural molded into the housing to handle that.

 

[ilovevocs]

Interesting and expensive stuff !



Scuff the surfaces with some sandpaper and wipe clean.

Good thought on prep. I like to wash all my plastic parts in dish soap and water, using a 3m scotch bright pad.

The soapy water removes any release agent left on the part and the scotch bright will give you an mechanical tooth without the fuzz that occurs with other methods.

You should have a very dull finish before you proceed with any type of glue or epoxy.

 

[AZ Pete]

Lock tite makes a product called super glue plastic border. It has a felt tip pen that is a primer and a tube of super glue....about $4, and it works. Might want to try some.


Sent from my iPad using Tapatalk

 

[clubairth]

That's a very good suggestion about posting ALL your photo's directly to whatever forum you are on. Picture hosting sites are garbage and they will all eventually crash and burn as we have seen. They are a bad idea if you plan to keep your photo's!

Go to any forum including this one there are hundreds and thousands of blank pictures or of kittens licking themselves. When you post direct that picture will last as long as that forum does.
.
.
.

 

[Bacon!]

What about the kludgy, old forum implementations where attached images don't work well?

The self hosted image size limitations on this forum are poor at best, and unusable at worst (if you need to see detail). 620 x 280 downsizing unless you click and do a popup? Even then it's downsized.

Sometimes you need a good picture now, not a poor one that's still live 5 years later.

 

[CJ7VFR]

Is there a limit on the image resolution that the built in image feature can handle? Those, they are "so big"....

I have not hit a limit on the image resolution yet. I use a 20 megapixel digital camera to take my pictures, and they are pretty large in file size. But so far they have all worked when I uploaded them via the manage attachments.

I think where the limit would come into play is when you attach a picture directly to a post via an online picture hosting site or if you attach the picture directly from a website where the picture was already pretty big.

But when you do them as thumbnails there doesn't seem to be a limit. At least not that I have encountered.

Jim

 

[Bacon!]

^ That's not what I'm seeing. Here is the same image (resolution 1600x1600), online hosting site vs added as an attachment. Not only does the hosting site image start larger, click both and you see the attachment was downsized to 999x999.

Edit: Now this post has completely lost (it just vanished after I refreshed this topic page) the hosted/linked image, so two issues instead of one.

 

[Joweebananas]

Havent used too many different types of plastic bonding, but the shop i work at currently uses 3M plastic repair.
https://www.amazon.com/gp/aw/d/B002...f_4?ie=UTF8&psc=1&refRID=64HY0NB5FM5GFGDY2Q6M

It works decent as long as both plastics are scuffed down & wouldnt hurt to apply adhesion promoter to ensure it holds. Not certain if it would apply to your project, but i drill small holes down the edges before i put the glue on. This way the glue fills the holes & bonds to itself as well as the different plastics