I have some small pieces of 1/4" Lexan, 3.5" long. I need to cut parallel
grooves in one surface, 1/16" x 1/16", spaced 1/4" apart. The best idea I've
had so far is a rotary tool with a cutting wheel mounted on a board. Here's
the hasty version of this rig:
www.nopoliticalcalls.com/grooves.jpg
It cuts well, but it leaves curls of cuttings melted to the sides of the
grooves that are a PITA to remove without scratching the Lexan:
www.nopoliticalcalls.com/cuttings.jpg
Any ideas how to minimize such curls, or how to remove them easily and
cleanly?
I was thinking along the lines of saving the cost of an air compressor.
:-) I have a set of mini attachments for cleaning PCs and sewing
machines that will restrict the air stream, focus it where it's needed,
and increase velocity. That's the theory, anyway.
I've gone to interesting lengths to ensure that the work feeds parallel
to the blade. I'm rather pleased with the results now. The melted waste
is greatly reduced, and I find that I can buff it off with a fiber
wheel on my bench grinder without scratching the Lexan.
Still, I look forward to receiving my mini saw blade this week.
David Hakala wrote:
> I have some small pieces of 1/4" Lexan, 3.5" long. I need to
> cut parallel grooves in one surface, 1/16" x 1/16", spaced
> 1/4" apart. The best idea I've had so far is a rotary tool
> with a cutting wheel mounted on a board. Here's the hasty
> version of this rig:
>
> www.nopoliticalcalls.com/grooves.jpg
>
> It cuts well, but it leaves curls of cuttings melted to the
> sides of the grooves that are a PITA to remove without
> scratching the Lexan:
>
> www.nopoliticalcalls.com/cuttings.jpg
>
> Any ideas how to minimize such curls, or how to remove them
> easily and cleanly?
Dave...
I've had fairly good luck routing Lexan sheet stock. The smallest
bit that I've used has been 1/8"; but I can't see any reason why
you couldn't route it with a 1/16" bit, as long as you maintain a
feed rate that avoids the heat buildup.
Looking back at my notes, I cut the 1/8" Lexan with the 1/8"
two-flute spiral bit at 18000 RPM with a 1.5"/sec feed rate. I'm
not sure this is ideal; but it worked for me.
--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/solar.html
"David Hakala" <[email protected]> wrote in message
news:[email protected]...
>I have some small pieces of 1/4" Lexan, 3.5" long. I need to cut parallel
> grooves in one surface, 1/16" x 1/16", spaced 1/4" apart. The best idea
> I've had so far is a rotary tool with a cutting wheel mounted on a board.
> Here's the hasty version of this rig:
>
> www.nopoliticalcalls.com/grooves.jpg
>
> It cuts well, but it leaves curls of cuttings melted to the sides of the
> grooves that are a PITA to remove without scratching the Lexan:
>
> www.nopoliticalcalls.com/cuttings.jpg
>
> Any ideas how to minimize such curls, or how to remove them easily and
> cleanly?
>
>
>
Why not put the piece in the freezer first?
"sandman"
> Probably too much speed and the teeth aren't course enough.
> Cutting stuff like that calls for chip removal and cooling. Add a
> powerful blast of concentrated air at the point of the saw cut.
Interesting. I tried a cutting wheel about 1/16" thick and 1" dia. at about
10,000 rpm. Slowing it down didn't help. Then I tried a diamond-coated
wheel, a bit more than 0.12" thick, which fits the steel plate that goes
into this groove perfectly. That went better but I still get melted Lexan.
I guess I need one of those itsy-bitsy circular saw blades, and I know
exactly where to get one!
I suppose my vacuum cleaner will do for a powerful blast of air. :-)
Thanks, sandman!
On Fri, 31 Dec 2004 19:43:30 -0500, sandman <[email protected]>
wrote:
>In article <[email protected]>,
> "David Hakala" <[email protected]> wrote:
>
>> "sandman"
>> > Probably too much speed and the teeth aren't course enough.
>> > Cutting stuff like that calls for chip removal and cooling. Add a
>> > powerful blast of concentrated air at the point of the saw cut.
>>
>> Interesting. I tried a cutting wheel about 1/16" thick and 1" dia. at about
>> 10,000 rpm. Slowing it down didn't help. Then I tried a diamond-coated
>> wheel, a bit more than 0.12" thick, which fits the steel plate that goes
>> into this groove perfectly. That went better but I still get melted Lexan.
>>
>> I guess I need one of those itsy-bitsy circular saw blades, and I know
>> exactly where to get one!
>>
>> I suppose my vacuum cleaner will do for a powerful blast of air. :-)
>>
>> Thanks, sandman!
>>
>>
>
>David, I was more thinking along the lines of a blow gun with air from a
>compressor. High pressure to blow the chips away from the action.
>I don't think a vacuum would have the concentrated oomph.
>The cooling would be a side-benefit.
>
>I would also make sure that the travel of the work would be parallel to
>the blade.
Why not use a hand-router [the motorless kind of yore] with a guide
that can be clamped to parallel markings on another piece made of wood
of the same thickness? You could have an outer jig frame that holds
the piece and one side having the markings. You'd need a craftsman's
steady hand and a razor-sharp blade. I've done it before [with wood]
and used more materialfor the jig than for the object being worked on.
In article <[email protected]>,
"David Hakala" <[email protected]> wrote:
> I have some small pieces of 1/4" Lexan, 3.5" long. I need to cut parallel
> grooves in one surface, 1/16" x 1/16", spaced 1/4" apart. The best idea I've
> had so far is a rotary tool with a cutting wheel mounted on a board. Here's
> the hasty version of this rig:
>
> www.nopoliticalcalls.com/grooves.jpg
>
> It cuts well, but it leaves curls of cuttings melted to the sides of the
> grooves that are a PITA to remove without scratching the Lexan:
>
> www.nopoliticalcalls.com/cuttings.jpg
>
> Any ideas how to minimize such curls, or how to remove them easily and
> cleanly?
>
>
>
Probably too much speed and the teeth aren't course enough.
Cutting stuff like that calls for chip removal and cooling. Add a
powerful blast of concentrated air at the point of the saw cut.
In article <[email protected]>,
"David Hakala" <[email protected]> wrote:
> "sandman"
> > Probably too much speed and the teeth aren't course enough.
> > Cutting stuff like that calls for chip removal and cooling. Add a
> > powerful blast of concentrated air at the point of the saw cut.
>
> Interesting. I tried a cutting wheel about 1/16" thick and 1" dia. at about
> 10,000 rpm. Slowing it down didn't help. Then I tried a diamond-coated
> wheel, a bit more than 0.12" thick, which fits the steel plate that goes
> into this groove perfectly. That went better but I still get melted Lexan.
>
> I guess I need one of those itsy-bitsy circular saw blades, and I know
> exactly where to get one!
>
> I suppose my vacuum cleaner will do for a powerful blast of air. :-)
>
> Thanks, sandman!
>
>
David, I was more thinking along the lines of a blow gun with air from a
compressor. High pressure to blow the chips away from the action.
I don't think a vacuum would have the concentrated oomph.
The cooling would be a side-benefit.
I would also make sure that the travel of the work would be parallel to
the blade.
On 31 Dec 2004 23:28:49 -0800, [email protected] wrote:
>Because I've never hear of a motorless hand router, and I don't have
>the steady hand you mentioned, either. :-)
OK, "Router plane".
Look here:
http://www.stanleytools.com/default.asp?CATEGORY=PLANES&TYPE=PRODUCT&PARTNUMBER=12-071&SDesc=Router+Plane
"Steady" is relative, and you can use a guide.
"Morris Dovey" <[email protected]> wrote in message
news:[email protected]...
> David Hakala wrote:
>
> > I have some small pieces of 1/4" Lexan, 3.5" long. I need to
> > cut parallel grooves in one surface, 1/16" x 1/16", spaced
> > 1/4" apart. The best idea I've had so far is a rotary tool
> > with a cutting wheel mounted on a board. Here's the hasty
> > version of this rig:
> >
> > www.nopoliticalcalls.com/grooves.jpg
> >
> > It cuts well, but it leaves curls of cuttings melted to the
> > sides of the grooves that are a PITA to remove without
> > scratching the Lexan:
> >
> > www.nopoliticalcalls.com/cuttings.jpg
> >
> > Any ideas how to minimize such curls, or how to remove them
> > easily and cleanly?
>
> Dave...
>
> I've had fairly good luck routing Lexan sheet stock. The smallest
> bit that I've used has been 1/8"; but I can't see any reason why
> you couldn't route it with a 1/16" bit, as long as you maintain a
> feed rate that avoids the heat buildup.
>
> Looking back at my notes, I cut the 1/8" Lexan with the 1/8"
> two-flute spiral bit at 18000 RPM with a 1.5"/sec feed rate. I'm
> not sure this is ideal; but it worked for me.
>
> --
> Morris Dovey
> DeSoto Solar
> DeSoto, Iowa USA
> http://www.iedu.com/DeSoto/solar.html
Careful Morris ... if they catch wind that you used a Shopbot, you'll get
all sorts of grief. :) Liked the layout shots from one of your earlier
posts btw.
I'd like to see more of your machine refinements.
Regards,
Rick