Hi,
I'm building an overarm blade guard from polycarbonate, solvent welded with
a made-for-polycarbonate cement (Caseway Industrial Products SC-325). The
only info on the can is "Fast setting cement for polycarbonate, medium to
high bond strength."
My question is, how fast does solvent welding work? If anybody knows this
stuff in partcular, that would be great. Barring that, how long in general
does it take? An hour? Four? Overnight?
The first pieces went together very well, and I've got a couple of light
weights on them to keep them together. It's been a couple of hours, and I'm
wondering if it's safe to take the weights off and work on it some more.
Anybody any relevant experience to share?
Thanks,
Lewis
You need "light tight" joints - no gaps to get a good
"weld". It's capillary action that draws the solvnet
into the joint. As insurance, after the solvent has
done its work, drill holes, insert small brads acrossed
the joint and put a little solvent on each. It'll go
into any space between the brad and the sides of the
hole, assuming the fit is good, and semi bond the
polycarb to the brad.
charlie b
In article <QKWQb.19837$U%5.155645@attbi_s03>,
Lewis <[email protected]> wrote:
>Hi,
>I'm building an overarm blade guard from polycarbonate, solvent welded with
>a made-for-polycarbonate cement (Caseway Industrial Products SC-325). The
>only info on the can is "Fast setting cement for polycarbonate, medium to
>high bond strength."
>
>My question is, how fast does solvent welding work?
"Fast" <grin>
> If anybody knows this
>stuff in partcular, that would be great. Barring that, how long in general
>does it take? An hour? Four? Overnight?
Depends on how big the joint is. the farther it is from the 'middle' of
the join to 'exposed to air', the longer.
>The first pieces went together very well, and I've got a couple of light
>weights on them to keep them together. It's been a couple of hours, and I'm
>wondering if it's safe to take the weights off and work on it some more.
Usually, you're dealing in the range of 'minutes' to 'a few tens of minutes',
at the outside.
There is usually no 'curing' involved -- when the volatiles have dissipated,
the job is done.
BTW, 'pressure' to hold the joint together doesn't mean much with this type
of joinery. It's like metal-welding -- holding the pieces 'fixed and immovable'
in relation to each other is the critical item. "3rd hand" jigs are wonderful.
>Anybody any relevant experience to share?
"If in doubt, _ASK_THE_MANUFACTURER_" is my experience. :)
There is often a toll-free number on the container.
Doug,
Thanks for the info. No, there's nothing on the can about how long to expect
the bonding to take, except the phrase "fast setting." I've been giving it
an hour or two between successive pieces, and that seems to be plenty of
time.
Lewis
"Doug Miller" <[email protected]> wrote in message
news:[email protected]...
> In article <QKWQb.19837$U%5.155645@attbi_s03>, "Lewis"
<[email protected]> wrote:
> >Hi,
> >I'm building an overarm blade guard from polycarbonate, solvent welded
with
> >a made-for-polycarbonate cement (Caseway Industrial Products SC-325). The
> >only info on the can is "Fast setting cement for polycarbonate, medium to
> >high bond strength."
> >
> >My question is, how fast does solvent welding work? If anybody knows this
> >stuff in partcular, that would be great. Barring that, how long in
general
> >does it take? An hour? Four? Overnight?
>
> It doesn't say on the can?
>
> No experience with polycarbonate, but FWIW, when I have solvent-welded
acrylic
> plastic (Plexiglas), it bonded within a few minutes at most.
>
> --
> Doug Miller (alphageek at milmac dot com)
>
> How come we choose from just two people to run for president and 50 for
Miss America?
Thanks to all!
The joints were tight; a very slow feed with an 80-tooth blade on a
table saw makes a nice clean edge in polycarbonate. I was just using
weights to hold things in place, not to close gaps. I wetted out the
edges I was joining with solvent on a Q-tip, then put the pieces
together. Then I touched the joint with a sopping Q-tip and the
solvent was drawn into the joint by capillary action. A syringe would
probably have been neater -- I got a few runs down the plastic faces
with my Q-tip method -- but this way seemed to work well. The material
is 3/8 inch, and some is joined at 45 degrees, so the center of some
of the joints was fairly far from the edges. Towards the end, I sped
up the process and only allowed a half an hour before handling. No
problems.
I'm planning to support the blade guard with PVC pipe. In a mock-up,
the 3 inch and 4 inch pipe I'll be using seem to be plenty sturdy to
support the guard, and they will do double duty as support and dust
collection. I don't think I've ever seen an overarm blade guard
support made with PVC -- it seems to me to be a natural. Maybe I'm
missing something.... Time will tell!
Lewis
On Sun, 25 Jan 2004 21:42:08 GMT, "Lewis" <[email protected]> wrote:
>Hi,
>I'm building an overarm blade guard from polycarbonate, solvent welded with
>a made-for-polycarbonate cement (Caseway Industrial Products SC-325). The
>only info on the can is "Fast setting cement for polycarbonate, medium to
>high bond strength."
>
>My question is, how fast does solvent welding work? If anybody knows this
>stuff in partcular, that would be great. Barring that, how long in general
>does it take? An hour? Four? Overnight?
>
>The first pieces went together very well, and I've got a couple of light
>weights on them to keep them together. It's been a couple of hours, and I'm
>wondering if it's safe to take the weights off and work on it some more.
>
>Anybody any relevant experience to share?
>Thanks,
>Lewis
>
Once the guard is finished, please share details and photos so we can
follow your lead as our needs arise.
Clif
In article <QKWQb.19837$U%5.155645@attbi_s03>, "Lewis" <[email protected]> wrote:
>Hi,
>I'm building an overarm blade guard from polycarbonate, solvent welded with
>a made-for-polycarbonate cement (Caseway Industrial Products SC-325). The
>only info on the can is "Fast setting cement for polycarbonate, medium to
>high bond strength."
>
>My question is, how fast does solvent welding work? If anybody knows this
>stuff in partcular, that would be great. Barring that, how long in general
>does it take? An hour? Four? Overnight?
It doesn't say on the can?
No experience with polycarbonate, but FWIW, when I have solvent-welded acrylic
plastic (Plexiglas), it bonded within a few minutes at most.
--
Doug Miller (alphageek at milmac dot com)
How come we choose from just two people to run for president and 50 for Miss America?
When I was building with polycarbonate in the past, I recall that
typically it only took a short time for the "weld" to setup - a couple
hours is probably more than adequate
John
On Sun, 25 Jan 2004 21:42:08 GMT, "Lewis" <[email protected]> wrote:
>Hi,
>I'm building an overarm blade guard from polycarbonate, solvent welded with
>a made-for-polycarbonate cement (Caseway Industrial Products SC-325). The
>only info on the can is "Fast setting cement for polycarbonate, medium to
>high bond strength."
>
>My question is, how fast does solvent welding work? If anybody knows this
>stuff in partcular, that would be great. Barring that, how long in general
>does it take? An hour? Four? Overnight?
>
>The first pieces went together very well, and I've got a couple of light
>weights on them to keep them together. It's been a couple of hours, and I'm
>wondering if it's safe to take the weights off and work on it some more.
>
>Anybody any relevant experience to share?
>Thanks,
>Lewis
>
Will do. Should be up in a few days.
Lewis
"Clif" <[email protected]> wrote in message
news:[email protected]...
>
> Once the guard is finished, please share details and photos so we can
> follow your lead as our needs arise.
>
> Clif