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Are you cutting out shapes or just straight lines ? How thick is the PVC ?
After cutting pvc and some other plastics I'll lightly sand or abrade with a file and then run down the edge with a heat gun to take out the rough edge. Be careful to not overheat the substrate. I cut large PVC panels with a panel saw or even the skill saw with a guide. Use a sharp blade as always and use air to clean the saw when done.
Thin material I cut with an exacto or other hand type razor. The snap off kind sometimes. This takes extra care. I have found that the trick is to make multiple cuts with only minimal pressure. Pressing down too hard leads to a sore wrist and dull blades, and maybe cutting yourself.
Hope that helps a bit !
Steve
-------------------- Steve Aycock Designs 3489 Oswald St. Johns Island, SC zaor@warpdriveonline.com Posts: 124 | From: Charleston, SC | Registered: Feb 2003
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I cut out PVC letters 3mm or 5mm thick on my scrollsaw, and get the same roughness, but find if I go round with my nail it just drops off, with a little effort, leaving a really nice clean cut.
I have a Hegner Multicut scrollsaw and I use a Nr 9 blade.
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Hi Janette, I'm surprised you're just getting around to having this problem. It's heat from the blade friction causing your troubles. Going very slow helps but is not efficient. We buy sabre saw blades with specifically labeled for PVC. Something in the tooth pattern I guess, but they work SO much better. What brand of scroll saw do you have? one of those stationary jobbers, or a hand held 'sabre' saw? If you cannot get PVC rated blades for your scroll saw you are in for contimued problems I'm afraid. Slow it down and try coarser tooth profiles or even those reverse ground type that are thinner in the back than front, anything to reduce friction and keep the material moving away from the blade.
You tend to sacrifice smoothness for heat. The real problem becomes how to smooth out or fill the edges after it's cut.
SONGPAINTER Original Sign Music by Sign People NOW AVAILABLE on CD and the proceeds go to Letterville's favorite charity! Click Here for Sound Clips! Posts: 1974 | From: Orleans, MA, Cape Cod, USA | Registered: Nov 1998
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posted
Like Joe said, Slow it down. Do you have a variable speed on your saw? The Bosch blade in mine is about ten teeth per inch and every other one is short. Any blade rated for plastic will work. If you can tape a piece of masking tape on the underside of the cut, it eliminates that ragged edge. That's an old trick from the cutting acrylic days...... A bandsaw gives a nice clean cut if you cutting smaller shapes.
-------------------- Jeff Ogden 8727 NE 68 Terr. Gainesville FL, 32609 Posts: 2138 | From: 8827 NE 68 Terr Gainesville Fl 32609 | Registered: Aug 2002
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I've actually been having this problem for awhile on cutting small curvy shapes and letters. On a last job, I just had too many little peices to repair, sand, and fiddle with, so I thought there just had to be a better way.
Been cutting usually 1/8" and 1/4" thick peices. I have a rigid scroll saw I'm using. No variable speed on it tho. A band saw is actually on my list of things to buy too.
I really appreciate all your advice. Thanks, Nettie
-------------------- "When Love and Skill Work Together ... Expect a Masterpiece"
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Nettie, This last month we have cut so much stuff with a jig saw, it promted me to make the "Let's talk CNC routers" posts.
We have 3 jig saws, a roto zip, radial arm saw, and one of those table top hobby saws with the round platform, (not a band saw), and a hand router.
We are cutting 6mm (1/4 ) and 13mm (1/2) PVC.
The radial arm saw cut all the strait edges just fine, the router with a home made attachment to cut circles and letter O,C,&G perfectly, and the jig saws to cut the rest. The jig saws have different blades in them and we got different results and they all sucked! Lots of clean up. The little roto zip is great on PVC but a little hard to control for perfection.
My conclusion: any thing that goes up and down is is bad on PVC and anything that goes round and round is good on PVC.
It took four of us 2 days to cut and sand a job that would have taken a router 3 hours to cut with 1 person, who could have been busy doing other things while the router was cutting.
I getting a router! PERIOD! NOW!
[ August 11, 2003, 08:58 AM: Message edited by: Dave Draper ]
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Nettie,,,,,,,,,, have you tried the RotoZip ??? Even the regular hand-held router works well also. I get the 1/4" up-spiral bits from Hartlaur Bits and it does an EXCELLENT job with NO rough edges. Just lay your PVC sheet on the white cheap styrofoam and cut away !!
-------------------- John Smith Kings Bay Signs (Retired) Kissimmee, Florida Posts: 816 | From: Central Florida - The Sunshine State | Registered: Jan 2000
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posted
Yup. Johnathon got it. If you're still unhappy with the edge, using heavy rubber gloves, take a rag and rub the edge with MEK. It will soften and glaze the edge smooth. Don't inhale that crap!
k31
-------------------- Pierre St.Marie Stmariegraphics Kalispell,Mt www.stmariegraphics.com ------------------ Plan on knowing everything before I die and time's running out! Posts: 4223 | From: Kalispell,Mt 59903 | Registered: Mar 2000
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