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Steve Clarkson
03-06-2010, 11:37 AM
Is there anything (glass, etc) that Weld On won't stick to?

My problem is that let's say I cut out the letter "R" from a piece of 1/8" red acrylic and green acrylic. Now I want to inlay the green "R" in the red acrylic. When I try to do it vertically....the weld on drips and my fingers leave prints that won't come off. If I try to do it horizontally.....let's say on a piece of paper......the acrylic sticks to whatever it was on.

Any tips or suggestions?

Thanks!

Larry Bratton
03-06-2010, 11:53 AM
Is there anything (glass, etc) that Weld On won't stick to?

My problem is that let's say I cut out the letter "R" from a piece of 1/8" red acrylic and green acrylic. Now I want to inlay the green "R" in the red acrylic. When I try to do it vertically....the weld on drips and my fingers leave prints that won't come off. If I try to do it horizontally.....let's say on a piece of paper......the acrylic sticks to whatever it was on.

Any tips or suggestions?

Thanks!
I assume your talking about Weldon #3? You might try Weldon #16, it is the same stuff except it has the consistency of syrup. I will caution you however, that it also has to be used carefully. You can buy it in 5oz tubes or in gallon cans. If you use the tubes, be careful about squeezing the tube when you first open it, it will just flow out with a very gentle squeeze.

Dee Gallo
03-06-2010, 12:02 PM
Steve,

I used it with Reynolds Non-Stick Foil... didn't stick to the foil.

:) dee

Doug Griffith
03-06-2010, 12:08 PM
In some cases you can leave the masking on or just peel away only the area that's being glued.

Steve Clarkson
03-06-2010, 12:27 PM
Thanks....I'll try those ideas.

John Noell
03-06-2010, 1:44 PM
....the weld on drips After watching some videos, it seems that one trick is to use a squeeze bottle with hypodermic tip. While the bottle is vertical you squeeze the sides and SLOWLY release the pressure (but only part way) while turning it over and putting the tip on the join. Then you stop releasing the sides just enough for the warmth of your fingers to vaporize and push out some Weld-On. When enough has come out, start releasing the sides again, turn it upright, and you are there! It takes a fair bit of practice to avoid any drips but it can be done. I USUALLY avoid drips this way. :)

AL Ursich
03-06-2010, 2:21 PM
Good tips...

AL

David Harvey
03-06-2010, 6:54 PM
Is there anything (glass, etc) that Weld On won't stick to?

My problem is that let's say I cut out the letter "R" from a piece of 1/8" red acrylic and green acrylic. Now I want to inlay the green "R" in the red acrylic. When I try to do it vertically....the weld on drips and my fingers leave prints that won't come off. If I try to do it horizontally.....let's say on a piece of paper......the acrylic sticks to whatever it was on.

Any tips or suggestions?

Thanks!
Steve,
I use a hyperdermic syringe with a blunt metal needle (similar to the one shown at the link below). This allows controlled application of the Weld-On right at the point of contact where the parts to be glue meet. I have used the bottles with the needle, but it is 'way to easy' to dispense gobs of 'too much cement', even with a slight amount of 'squeeze' on the bottle. The company below sells the syringe and you can also order the blunt needles from them too. I'm sure there are many more sources you can get these from also as they are used extensively in the electronics industry for precise dispensing of glues, lubricants, etc.

http://jensenglobal.com/cgi-bin/jgd1/JG3CC-LL.html

...as for the fingerprints...all I can suggest there is to properly support your work piece before you apply the glue so you don't have to hold it while gluing.

hope this helps....

Martin Boekers
03-06-2010, 8:53 PM
Steve,

I believe Weld On isn't a glue in the normal sense. It is a solvent that actually melts the acrylic and creates what is actually better then a glue bond. If done properly the pieces actually become one.

Another point that I believe is true with it, it needs a lack of oxygen for it to bond. That maybe why you get fingerprints when you touch the piece while bonding. I have trouble getting a clean bond on acrylic pieces to the base and was told that the two surfaces may not be completely flat and an air pocket develops. It will etch though even just setting on an acrylic surface sometimes polish will help other times not.

I have variable results with it and haven't been able to use it consistantly.
When I have a few bucks to spare I may set up a UV system with a UV glue as this will work with glass and acrylics also.

Dee, thinks for the tip on foil! I have 50 small pieces to bond next week and I'll be trying that out!


Marty

Joe Peacock
03-06-2010, 9:15 PM
You might want to try the teflon sheets like bakers use. You can get them is pretty big sizes.
You can get them here http://www.jbprince.com/pastry-silpats-non-stick-baking-mats/teflon-baking-sheet.asp#jbp_full_desc at a pretty reasonable price.
Joe

Bill Cunningham
03-09-2010, 8:36 PM
Not much will stick to good old fashion waxed paper..

Steve Clarkson
03-09-2010, 11:55 PM
Well I tried it with the foil and for the most part it worked.....the foil peeled right off when I was done. Honestly, the foil seemed to make the weld on set immediately on contact....as opposed to the 5 seconds it normally takes.

But the problem is that the piece was still a complete mess......the weld on got everywhere and basically damaged the piece.

How come when I walk into a convenience store and look at one of the POP displays made out of clear or transparent acrylic, you can't see ANY type of adhesive mark.....what do they use that is basically optically clear???????

Martin Boekers
03-10-2010, 3:00 PM
The YouTube videos make it seem so easy! I still have a tough time with it.

The bottle is tough to work with, better luck with a syringe.

I tried the foil, it's not that it sticks to it, it's either the vapor or where it touches the acylic leaves a slight etch. Sometime I can work it out with a polish sometimes not.

On award bases I've come to believe that the base and award are not perfectly flush, so an air pocket or bubble occurs which is VISABLE!

If I can free up some funds this your I'm going to try a UV set-up with UV curable adhesives that maybe the answer for me, as you can set it up so it looks good hit the UV lights then trim away access.

Does any one here use UV adhesives?

Thanks,

Marty

Mike Null
03-10-2010, 5:01 PM
I think Larry has given you an option and that is to use #16. What you are trying to do is glue the pieces together but you are using a solvent. As a solvent if it can make a bond it will melt the two pieces together and there's no telling how that will look since you're using two colors.

Try the #16 or try super glue but just small spots of it.

Martin Boekers
03-10-2010, 5:21 PM
Thanks! Itwill make my life ia bit less stressful!

Marty

Mike Null
03-10-2010, 7:30 PM
Marty

I am of the opinion that air pockets are the result of starving the joint more than anything else. The award piece should not have a polished bottom.

High humidity presents challenges when using this solvent.

Paul Brinkmeyer
03-10-2010, 8:51 PM
Is there any product that is more like a silicone to apply, that will dry clear and hard?
I guess what I am looking for is something that is more forgiving, but still clear.

The Point of sales displays that Steve asked about must be done on a high volume, and I would think are kinda idiot proof. Or automated.

And yes, I like idiot proof ways of doing things when I can.

Martin Boekers
03-10-2010, 9:08 PM
Marty

I am of the opinion that air pockets are the result of starving the joint more than anything else. The award piece should not have a polished bottom.

High humidity presents challenges when using this solvent.

Mike,

Since I buy the acrylic with the bases together, they are both already polished. Should I rough up the bottom os the awards before I add the solvent?

I guess if it isn't an air pocket that is creating the trouble bubble, maybe it could be a slight "peak" that is doing it?

Thanks for the help!

Marty

Mike Null
03-11-2010, 6:43 AM
Marty

The ones I buy usually have a matt finish on the bottom. If not I put some fine sandpaper on a glass and rub the bottom of the award on it to scuff it.

The people at ACI Plastics here in St. Louis gave me some lessons on how to cement acrylic and they're the source of my info.

If the bottom surface is polished it has probably been buffed. That might be the cause of high and low spots.

Bob Davis
03-11-2010, 10:28 PM
I've attached a lot of custom acrylic pieces to bases, and I've found the best results are obtained by flattening the join with an upright belt sander and a fairly rough (80 grit) belt.
The rough (and now perfectly square) flattened area allows a lot more solvent into the join and allows the air to escape. The acrylic melts and voila!... a perfect join and it's very strong after 10 or 15 minutes. Make sure you have removed all dust and grit before making the join.

Nathan Hawkes
03-11-2010, 10:53 PM
Is there any product that is more like a silicone to apply, that will dry clear and hard?
I guess what I am looking for is something that is more forgiving, but still clear.

The Point of sales displays that Steve asked about must be done on a high volume, and I would think are kinda idiot proof. Or automated.

And yes, I like idiot proof ways of doing things when I can.



Yes, there's another form of weld-on available that comes in a two-part mixing tube, but the gun alone for mixing is a couple hundred bucks. Also, its even more toxic to breathe. Think epoxy with clear plastic monomers.

Nobody uses the needle method??

Mike Null
03-12-2010, 5:36 AM
I have always used the small bottle with the needle.

Nathan Hawkes
03-12-2010, 10:46 PM
No; what I'm referring to is using small fine gauge sewing pins or wire as a riser, creating a perfectly even space in the entire length of the joint. You leave it for a minute or two, and pull the wires. Works every time to give bubble free perfect seams. You just have to have a jig to hold the pieces steady while the weldon works its magic. Weld-on #4 takes a bit longer with this method, but leaves less hazing marks than #3 where you have squeeze-out.

Nathan Hawkes
03-12-2010, 10:51 PM
FYI: putting weld-on on a flame polished edge isn't going to result in a good joint; flame polishing is SO easy compared to any other method, a lot of plastic shops use them. If you apply glue to a flame polished edge you get instant crazing.