by Anonymous Coward writes:
on Thursday September 03, 2015 @04:45PM (#50453659)
I happen to need some weird Delrin parts for a 1960s oscilloscope. My parts have cracks and Delrin is almost impossible to glue unless the surface is chemically prepared.
I wonder if Joshua can tell us if there's a way to prepare the surface correctly at home? And what specific adhesive works?
I happen to need some weird Delrin parts for a 1960s oscilloscope. My parts have cracks and Delrin is almost impossible to glue unless the surface is chemically prepared.
I wonder if Joshua can tell us if there's a way to prepare the surface correctly at home? And what specific adhesive works?
Nothing sticks WELL to Delrin/acetal. Epoxies can be used to bond it, but it's not recommended at all if any other means of connection is feasible. Its non-reactive and low-friction properties are directly related to its very low surface energy, which makes bonding work poorly. Acrylic is much better if you need to glue, since superglue (cyanoacrylate) bonds extremely well and matches its mechanical properties fairly well. Polycarbonate is also good.
Try double sided tape, I've managed to stick pieces of Teflon together with some of those for test setups. But for acetal sheets if you really *must* glue first use 250 - 300 grit abrasive cloth and then an epoxy based glue.
Do you need Delrin, or can you remake the parts from a different material? This company makes adhesives for Delrin: http://reltekllc.com/adhesives... [reltekllc.com]
by Anonymous Coward writes:
on Thursday September 03, 2015 @05:14PM (#50453825)
Use Loctite 770 to prep the surface, then use regular super glue (cyanoacrylate). They also sell it at hardware stores as "glue for hard to bond plastics" as a 2 part system (the 770 and superglue). I've found the bond to be very strong this way (getting up to the point where Delrin will fail before the bond).
Delrin is a thermoplastic; my first thought would not be to glue it with some other substance.
(assuming you are in the USA, which you may not be)
Harbor Freight makes a plastic welder for $65. There's better name-brand ones around for $300-$700.
Two other possibilities for cheaply welding plastic: cheap soldering irons (~15W - 30W heat, $20) and mini heat guns ($10 - $30).
If it is not a cosmetic issue, I have also seen thermoplastic parts repaired the following way... You get a small piece of aluminum screen, place it over the break and rub it in with a hot soldering iron.
Whoah, Delrin? (Score:0)
I happen to need some weird Delrin parts for a 1960s oscilloscope. My parts have cracks and Delrin is almost impossible to glue unless the surface is chemically prepared.
I wonder if Joshua can tell us if there's a way to prepare the surface correctly at home? And what specific adhesive works?
Re: (Score:2)
I happen to need some weird Delrin parts for a 1960s oscilloscope. My parts have cracks and Delrin is almost impossible to glue unless the surface is chemically prepared.
I wonder if Joshua can tell us if there's a way to prepare the surface correctly at home? And what specific adhesive works?
Nothing sticks WELL to Delrin/acetal. Epoxies can be used to bond it, but it's not recommended at all if any other means of connection is feasible. Its non-reactive and low-friction properties are directly related to its very low surface energy, which makes bonding work poorly. Acrylic is much better if you need to glue, since superglue (cyanoacrylate) bonds extremely well and matches its mechanical properties fairly well. Polycarbonate is also good.
Re: (Score:2)
can you remake in another plastic? Reltek adhesiv (Score:2)
Do you need Delrin, or can you remake the parts from a different material? This company makes adhesives for Delrin:
http://reltekllc.com/adhesives... [reltekllc.com]
Re:Whoah, Delrin? (Score:4, Informative)
Use Loctite 770 to prep the surface, then use regular super glue (cyanoacrylate). They also sell it at hardware stores as "glue for hard to bond plastics" as a 2 part system (the 770 and superglue). I've found the bond to be very strong this way (getting up to the point where Delrin will fail before the bond).
Re:Whoah, Delrin? (Score:4, Interesting)
(assuming you are in the USA, which you may not be)
Harbor Freight makes a plastic welder for $65. There's better name-brand ones around for $300-$700.
Two other possibilities for cheaply welding plastic: cheap soldering irons (~15W - 30W heat, $20) and mini heat guns ($10 - $30).
If it is not a cosmetic issue, I have also seen thermoplastic parts repaired the following way... You get a small piece of aluminum screen, place it over the break and rub it in with a hot soldering iron.