Gluing PETG  

Re: Gluing PETG

PETG resists most domestic glues and chemicals...
there are some nasty chemicals will work on PETG, but they are not easily available and need special handling which is probably beyond most users.

probably your best bet is to create surface artifacts that will cause parts to have indents or slots for adhesive to latch into, as they are unlikely to actually bond to PETG, reliably

regards Joan

Re: Gluing PETG

I've had some success with "plumbers" glue. I've not looked at it's chemical makeup, just slapped some in between two PETG prints and let them dry. Don't know if it's on Joan's nasty list but it seemed to work ok.

Re: Gluing PETG

The only thing that works reliable for me is to weld the parts together.
Easy to do with a temperature controlled soldering station and a new (at least clean) tip.
You need a little bit practice, but it works very good, and the results are resiliant.
But only as long as you can live with a bit of rughness where you welded the parts.
You can weld it using the existent Material only, or you can use the filament you used for the print as a welding rod.
In the second case you are able to sand it down and get a more or less smooth surface.

Re: Gluing PETG

I often need to glue polyethylenes of various types. They usually have low surface energy and don’t stick to much. You need to prime the surface first. Try:
http://www.loctiteproducts.com/p/sg_plstc/overview/Loctite-Plastics-Bonding-System.htm
Cheap and easy.

Re: Gluing PETG

You don't say where you are some I'm going to guess that you're in the USA. If you are then you can easily get this product from Amazon. It works great on PLA, ABS, and PET, plexiglass/acrylic. I haven't tried other materials.

https://www.amazon.com/gp/product/B003HNFLMY/ref=oh_aui_detailpage_o05_s03?ie=UTF8&psc=1

Note: It contains some solvents such as methylene chloride, which means this material should be handled with care (ie: gloves, such as nitrile, and used in a well ventilated area.

Re: Gluing PETG

Hi Everyone,

Thanks for the replies. I'll try that "nasty" Methylene Chloride stuff (I am in fact in the US, Portland Oregon to be precise). We are used to using products that you don't want to breathe, so we have all the ventilation setup that would be required.

Re: Gluing PETG

Has anybody tried friction welding with PETG? It's not the most attractive solution, but might be hidden away effectively.

Re: Gluing PETG

some years ago I was at a home and tool show in Boston MA. there was a chap selling a plastic welding outfit that he claimed would work on any thermo plastic (that is to say not on stuff like Bakelite). and he invited anyone to bring a broken piece of plastic and he would weld it. now they were probably shills as who takes broken plastic to a home show? but he had every thing from car parts to appliance parts and also from small toys to a fuel tank for a chainsaw. and while he used several techniques the one i remember looked a lot like Tig welding with hot air that he was controlling the temperature with a foot treadle and rods of plastic that amazingly were a close match to the 'random' parts he was brought.

the demo was impressive enough that I stopped and watched several times during the day... it was over 15 years ago so I don't recall any details or names and how much of it was snake oil I can not say but I guess there must be a need for rework in the manufacture of plastic parts that are above a value where it is cheaper to fix than to extrude another one

Re: Gluing PETG

My car was damaged and the repairers welded a split in my bumper... the weld was very robust, but they neglected to remove the raised weld bead...

now let's be honest, who wants a random weld line on the surface of their car...

if they had cut the surface back, the repair would have been invisible...

as it was, the repair was rejected...

Grumpy Joan...

Re: Gluing PETG

some years ago I was at a home and tool show in Boston MA. there was a chap selling a plastic welding outfit that he claimed would work on any thermo plastic (that is to say not on stuff like Bakelite). and he invited anyone to bring a broken piece of plastic and he would weld it. now they were probably shills as who takes broken plastic to a home show? but he had every thing from car parts to appliance parts and also from small toys to a fuel tank for a chainsaw. and while he used several techniques the one i remember looked a lot like Tig welding with hot air that he was controlling the temperature with a foot treadle and rods of plastic that amazingly were a close match to the 'random' parts he was brought.

the demo was impressive enough that I stopped and watched several times during the day... it was over 15 years ago so I don't recall any details or names and how much of it was snake oil I can not say but I guess there must be a need for rework in the manufacture of plastic parts that are above a value where it is cheaper to fix than to extrude another one

Plastic welding is actually common as muck in some industries. In particular HDPE is regularly welded (which is a good thing, because it's damn near impossible to glue).

Plastic kayaks in particular are commonly welded back together.

Re: Gluing PETG

do a google search on Plastic welding and you find many options from the $19.95 at the bottom to $400 and up "profesional" kits the break down into 2 main types the Hair dryer in steroids type based around various hot air gun designs

and the soldering iron designs with many various tip designs in the kits.

the first one you have all you need to experiment with if you have a hot air paint stripping gun in your tool chest... all you might need are some nozzles and temp trial nozzles can be copied from what you see the pro kits using in those google images your search returned by taking some aluminum beverage cans and cutting them out with plain house scissors and taping them up with stainless steel tape. use lengths of the filament you printed the part you are repairing as your filler /soldering rod and various metal shapes like screwdriver blades to shape the work when plyable.

for the other type I would the old fashioned Weller soldering gun found in any yard sale for few bucks if it works.

and using copper wire bend up various tip designs and once again use the filament as make up rod.

this way you can experiment to see it this is something you want to try to fix defects in your prints rather than print the whole object over again.

Re: Gluing PETG

Ah yes, good old Weller, who sometimes conveniently forget to put AC side fuses in their products. 😆

RE: Gluing PETG

Will any glue work with temporarily gluing extruder parts in place (reattaching the pinda probe holder in my case) until I can get a replacement part printed or sent to me? I have heard that there may be known issues with extruder parts on the mk3s eventually becoming weak or melting from high temperatures after being used for some time.  Prusa support suggested superglue and I've tried gorilla glue but it didn't work well enough.

RE: Gluing PETG

I've had good luck using Gorilla Super Glue Gel with PETG to PETG; PETG to a cigar box; PETG to wood.  Apply per the directions and hold/clamp until the glue sets up.

RE: Gluing PETG

I use either Gorilla or CA with a bonding agent.  

RE: Gluing PETG

Why can't you use a 3D printing pen to glue PETG to PETG with some molten PETG?

https://all3dp.com/1/best-3d-pen-reviews-price-3d-pens-buy-3d-printing-pen/

RE: Gluing PETG

As a quick repair solution I have had good luck with CA glues like Locktite 401.

I also "permanently" glued some PETG parts with it that hold up well after more than a year.

RE: Gluing PETG

Posted by: MM

Why can't you use a 3D printing pen to glue PETG to PETG with some molten PETG?

https://all3dp.com/1/best-3d-pen-reviews-price-3d-pens-buy-3d-printing-pen/

You certainly could.  

RE: Gluing PETG

Just tested PETG to PETG with Loctite Superglue 3 Gel-control and seems to work just fine. Leaves a bit of a white shine though.

Unless it fails after some time?