1st bot

technobots is where i got my 12mm bar when i needed some

around £5 plus postage

Well Ceri, Ive been saying since Newark (my first live event) that I wanted to build one but I didnt have the money to do it. Now that I have (thanks to employment) Im free to do so if I want to. :)

Ive still got a lot to learn though, and I want to be sure I can do it before starting. (and sort my free time out, heh)

(and Im watching the thread to see how a new builder makes progress with help from the community :))

Im needing some polycarbonate glue jjust to hold some or my polycarb together while im drilling and tapping holes.CAn anyone suggest a glue that would suit the job ? And what quantity would i need of it? And where can i get some
Ali

erm, al i can think of off my head would be Aryldite. That is a very strong glue, but takes a while to set. if you use that along with bolts i dont think you will be able to replace the panels very easily.

Hmm good point but i have 6 sheets of 6mm polycarb so i dont think it will be a problem ;)

Your best bet would be to try a sample of glues on seperate small sections of panels.

Go along to b and q or homebase and ask them if they have any glues specific for gluing plastics.

Araldite is good but you might also want to try loctite, doesnt get as good a stick but it sets a whole lot faster. Maybe even use a mixture of the two or other glues.

Their is an actual glue thats ment for polycarbonate, It is actually tiny amounts of polycarbonate in a liquid so the pieces are actually chemically bonded just as strongly as a premade piece. It is the equivelent of attaching two pieces of polythene (polyethene) together with ethene thus creating more polyethene where they are joined. The only problem is I dont know the name of teh glue.

ask John Reid
He knows about this sort of thing

Ian, what you are describing is called a solvent cement. For solvent welding polycarbonate (which is effectively what you are suggesting) methylene chloride is an efficient solvent though IIRC there are other chlorocarbons that will work. Dissolving some polycarbonate pieces in it would make a good cement. As you suggest there are commercial products for this, a bunch of solvent cements are marketed under the name Weld-on but you will have look further to find something more specific. It doesnt look optimal for something you just want to hold something in place temporarily as the bond is permanent. Also the solvents are farily severe so it should really be an outside only thing unless you have a fume-cuboard. For solvent welding with methylene chloride a hypodermic syringe is reccomended to use minimal amounts, some sanding may be required to remove the abrasion and chemically resistant protective film which may be found on some polycarbonate. Solvent joins do not reach full strength very quickly so for structural joins you would still need something to keep pieces in place (though that doesnt say much about its value as a temporary fixing)
Alistair I suggest you just stick with the measure twice, drill once rule or use some epoxy which will at least leave you able to take damaged pieces apart again without breaking more things.

Check pic on my profile this is how i attached my wheels to a ww motor. I used a small block of Nylon 6 with a hole slightly smaller than the hub, then bolted this on. i then drilled a hole through the side of the block and straight into the shaft. These i then taped out to take a bolt to hold them together. The 4 long bolts are to attatch the wheels to. The wheels never came of even after being hit by VORTEX.