Full Version: Bonding Acrylic Bases
From: Brian (BGALUSHA) [#1]
25 Feb 2007
To: ALL
Need a little help with some acrylic awards I'm doing. Really need a suggestion on technique. I'm about to perform my first bonding of acrylic bases. Are there any tips I should be aware of before I start? I have the standard bonding solution, hypodermic syringes, as well as a ventilated space (my open garage). Temperature is near freezing - is that a problem? How much of the base needs to be coated with the bonding solution? The acrylics are the standard Acrylic Idea Factory type. Needless to say, if I screw this up all the effort I've put into laser engraving them is out the door.
Thanks,
From: Mike (MIKEN) [#2]
25 Feb 2007
To: Brian (BGALUSHA) [#1] 25 Feb 2007
The temperature is a problem. Take the job in the house. The solvent cement is also sensitive to humidity. You'll get better results if the humidity is not higher than 40%.
It would be good if you had a practice piece or two. First, either apply masking tape, make a small simple jig or be sure you have a good eye for placement. Be sure both surfaces have been cleaned. Position the award on the base and tilt it away from you enough to allow room for the syringe to touch the base ( the underside ) of the award. Let the solvent flow to cover the entire base--don't skimp because you'll starve the joint. Position it as necessary moving it as little as possible while applying downward pressure. Your objective is to make a joint which has no air pockets; in other words the joint will be invisible. (sometimes I have managed to do this surprising myself)
If you get sloppy with the solvent have a rag handy and use it quickly then have various grades of plastic polish handy for the repair.
If you do the job in the kitchen turning on the exhaust fan should be adequate. The fumes are no laughing matter but you'll not have an open can or jar so not a problem. The solvent is highly flammable and is a carcinigen.
It also evaporates faster than anything I've ever seen (except for money in my wife's purse) so keep the lid on very tight.
EDITED: 25 Feb 2007 by MIKEN
From: Goodvol (JIMGOOD) [#3]
25 Feb 2007
To: Brian (BGALUSHA) [#1] 25 Feb 2007
The way I do it is to hold the blank in its inteded spot on the base. Then rock it back away from you and place your applicaor along the back edge that is still making contact with the base. Apply a bead along that back edge. It'll wick along that edge and then you bring the blank back up to its vertical position. Hold it in place and it'll bond quickly. I find that you only have a brief moment to make adjustments before it sets up and you'll lose your bond. I've had to start over becasue I was repositioning it too late. Sometimes your blank will try to "hydroplane" as you are initially positioning your blank. Just try to get it in its position as fast as possible. Clean up the extra glue that gets on your base.
That's how I do it and it might not be the best method. Hopefully others will provide more (and better) directions. :-)
I'd like to build a fixture that helps with positioning the blank. Sometimes my blanks weren't totally vertical or parallel with the edge of the base. I had to fix those awards.
Hope that helps.
Jim
From: Brian (BGALUSHA) [#4]
25 Feb 2007
To: Goodvol (JIMGOOD) [#3] 25 Feb 2007
OK,
I've given it a try but find i get residue that does NOT want to come off with my polishing compounds. What do you guys use for "clean up". Is there any way to get the award back apart once the bond is set?
This is beginning to look very ugly.
EDITED: 26 Feb 2007 by BGALUSHA
From: Harvey only (HARVEY-ONLY) [#5]
26 Feb 2007
To: Brian (BGALUSHA) [#4] 26 Feb 2007
Do not wipe off the extra adhesive. It will smear the melted plastic.
Do not blow on it. It will absorb the moisture from your breath and cloud up.
Just let it sit and evaporate. It may leave a faint line but far less than if you try to do something.
The big trick to a nearly seamless joint it to rock it into position, and DO NOT PRESS IT DOWN. It will mush more of the base down which would seem to be better, but will leave lines when the pressure is removed. Just let it sit and it will form the best bond.
From: Brian (BGALUSHA) [#6]
26 Feb 2007
To: Harvey only (HARVEY-ONLY) [#5] 26 Feb 2007
Thanks,
My initial panic has subsided and I've been doing OK. Messed up one out of about 40 but have an extra blank and will redo it. It really just needed more finese. I was working at it too hard (and yes too much pressure). Once I got the hang of "flooding" the joint, it has been working much more smoothly, but I could have used a lot more practice.
Thanks again,
From: Mike (MIKEN) [#7]
26 Feb 2007
To: Brian (BGALUSHA) [#6] 26 Feb 2007
For repairs.
I use the same process as if i were removing scratches. Turtle wax polishing compund, #2 Novus which is 1200 grit and then #1 Novus.
If you have to separate them you'll be risking ruining the award but if you have starved the joint to begin with then it shouldn't be too difficult.
It is important that the bottom of the award have a scuffed surface as opposed to polished. That allows the solvent to penetrate quicker and make a better bond.