PLA Specific Glue

I've had good luck with just Gorilla Crazy Glue.

@BillYo414 posted:

Does anybody use a specific glue for PLA? I'm printing parts for the frame of a building and one of those parts will be load bearing. Do you think CA glue is sufficient? Or should I look for a glue that chemically melts the parts together? Most of the parts are either pressed or pinned together so I'm not as concerned about those because a mechanical joint plus glue should be plenty strong.

The back up plan is to change over to ABS and use acetone to chemically melt/bond the parts but I hear ABS is a pain to print with so I was hoping to avoid that.

Looks like Norm Charbonneau used CA to glue together his PLA 3D printed Chuff Cams with good results:

3D Chuff Cam for my J1a

@Norm Charbonneau posted:

I am having almost too much fun learning about 3D printing. I primarily wanted to make internal parts to help improve my engine and rolling stock projects. My beloved TMCC Lionel J1a always had something close to the proper chuff, with two magnets on one of the trailing truck wheels pulsing a reed switch, giving it 3.8ish unsynched chuffs. Even when it had EOB years ago, the chuffs were pretty proper but definitely unsynched. I thought it might be nice to try making a proper 4 lobe cam, which is just a square with rounded corners. Adjusting the cam rotation could get me synched chuff on the crankpin at 0, 90, 180, and 270 degrees. PSC sells a similar device in cast brass but it is probably more practical for smaller scale models. Turned out I needed a microswitch bracket too as the original is long gone along with the smoke lever for the postwar style puffer unit this had originally. After some trial and error, I got it all working a couple nights ago. I learned quite a bit about dimensioning parts and making slots for component adjustment. The cam halves are CAed together and to the axle. I like that the PLA takes to gluing. I probably made 3 or 4 different switch mounts and two cams. My next cam will probably be mounted with small screws like the original sketch shown below. The width of the cam (9mm here) and the placement of the switch are dependent on how much lateral axle movement there is, but this axle is pretty tame in that axis compared to a lot of 3 rail stuff.

I've been hit and miss with the CA glue. I'm wondering if it's the fact that I'm using the gel instead of the just straight CA glue. I started using DucoCement but it takes a while to cure and whatnot.

The glue is important because many of my printed stuff is an assembly made of several parts.

I used to recommend Tenxr, before they went out of business.  However, another company picked up the reigns and sells Styrene Tack-It II.  Distributed by JM Hobby Supply, Pulaski, WI.  Web site is: www.jmhobbysupply.com.  This stuff drys almost instantly.  You apply it with a paint brush.. Add more fluid if you need the material melted more.  Once cured, it can make a very strong joint.  The strength is dependent on how much you apply at the start of the glue joint - the more you apply, the more the material melts, and totally fuses together.  Not that expensive, and I think worth a try. It essentially is methylene chloride in a jar, and works great on many types of plastics, especially styrene. 

I use gorilla ca glue with the blue lid works great.