hayman

Any suggestions for the best way to bond 1/4" thick Plexiglas.

I plan on using the Plexiglas for a (large) mold parting board. Making the frame and the actual parting surface out of Plexiglas. I really don't want to use screws especially in the parting surface. Not sure how 15 min epoxy would hold. Any thoughts?

Bill
http://www.paonline.com/hayman/video.htm

gjs

Acetone or MEK. The suppliers of materials for the "sign" industry sell little squirt bottles with a fine little tube for Wicking it into the joint between two sheets. IT WELDS the two not glue so it melts it so don't get it all over or you will not have a smooth surface. You clamp or weight the two parts and just drop the acetone on the seam between the two and it Wicks in really pretty easy. Epoxy would work, sand glue surface before glueing.

hayman

I had to go to a different Plexiglas supplier to get a solvent/bonding agent called Weldon.

Not cheep, $17 for what looks like 1.5 oz and $6 for a small squeeze bottle with a syringe needle attack.

Bill
http://www.paonline.com/hayman/video.htm

hayman

Okay, now that I can bond the Plexiglas how the heck do you cut it? I have a band saw that does a fairly good job but still has a buildup of melted goo after the cut. I don't have access to a jointer so I thought I could use my 12" disk sander to sand to a nice flat/straight edge. Wrong answer what's the best tools to use when cutting Plexiglas? I have some other critical dimensional cuts to make yet.

Thanks
Bill
http://www.paonline.com/hayman/video.htm

SDR-Hammer

For standard lay people like you and I that don’t have access to the “right” equipment to cut this stuff, I’ve found a table saw with a carbide blade produces good results. Be sure to wear safety glasses because small pieces do fly.

To clean up the edges use 150 grit sandpaper by hand. As you already discovered a power sander moves too fast creating heat and a lot of melting. Even if you did have a jointer I wouldn’t recommend running plexi through it. It will dull the knifes real quick.

rsieminski

I used to work with it all the time. We cut it on a table saw, ran the edge through a planer, and then hit it with a torch. I've had to skip the planer step when it was down. In that case, sand it as smooth as possible, and progressive runs accross a propane torch's flame. Practice 1st. Too hot and it'll bubble up, too cool and it takes forever, just right and the edge is as clear as glass.