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View Full Version : Anyone try making a Pantograph Plasma Cutter



JoeFin
01-08-2010, 09:10 PM
Been toying with the idea of making Pantograph Plasma Cutter and was wondering if anyone has tried with any success so far.

Found this pic on the internet and the concept looks pretty good althou it would take so modification to apply it to a plasma cutter

http://i54.photobucket.com/albums/g119/eshuffle/Picture095.jpg

Any thoughts ?

HarryG
01-08-2010, 09:45 PM
Not for use with a plasma unit, but I made one that uses an oxy-acetylene torch. The steel pattern is mounted above the torch and is traced by a magnetic rotary follower that runs around the pattern edge. It's the same design as the old Heath shape cutter.

datsun280zxt
01-08-2010, 10:16 PM
Not for use with a plasma unit, but I made one that uses an oxy-acetylene torch. The steel pattern is mounted above the torch and is traced by a magnetic rotary follower that runs around the pattern edge. It's the same design as the old Heath shape cutter.

Got any pictures?

doctor demo
01-08-2010, 10:41 PM
http://i522.photobucket.com/albums/w348/doctordemo/latest601-1.jpg
I didn't make this, but I did change it from oxy-acet to plasma. D.C. variable speed controll with a magnetic shaft on the motor that follows the pattern .

Steve

JoeFin
01-08-2010, 10:45 PM
http://i522.photobucket.com/albums/w348/doctordemo/latest601-1.jpg
I didn't make this, but I did change it from oxy-acet to plasma. D.C. variable speed controll with a magnetic shaft on the motor that follows the pattern .

Steve

Did you pick that up at the auction on 28th Ave

doctor demo
01-09-2010, 12:35 AM
Did you pick that up at the auction on 28th Ave
Oh Man, I missed yet another auction:mad: .
No Joe, it's been kicking around the shop for 4-5 years and gets used a couple of times a year. I still have the torch from it and it takes the Victor Journeyman size tips iirc.
28th ave. in what city?

Steve

sconisbee
01-09-2010, 03:06 AM
An old one for oxy probably seen before by all here but still...

From ships nostalgia
http://www.shipsnostalgia.com/guides/images/5/5a/Profileflamecutting.jpg

http://www.shipsnostalgia.com/guides/images/7/7a/Flamecutting1.jpg

Mark McGrath
01-09-2010, 03:34 AM
The problem with using a template or magic eye oxy-acetylene profile for plasma is that very few of them,especially the older ones are capable of producing the cutting speeds plasma needs.
The main problem I see with a pantograph machine is the same.Will you be able to move the stylus fast enough to keep the plasma cutting and how smooth would the movement be?
Mark.

ptjw7uk
01-09-2010, 04:19 AM
My oh my that second picture, gonna make a heavy guitar!

Peter

macona
01-09-2010, 05:00 AM
The problem with using a template or magic eye oxy-acetylene profile for plasma is that very few of them,especially the older ones are capable of producing the cutting speeds plasma needs.
The main problem I see with a pantograph machine is the same.Will you be able to move the stylus fast enough to keep the plasma cutting and how smooth would the movement be?
Mark.

Esab still sells bug-eye burners and they can be used with plasma or oxy-fuel. No problems.

Bad thing about bug eye burners are the heads are actually pretty fragile and they can be up to 3k to fix if the sensor gets out of whack.

There is a local company that makes custom Jeep parts. They have a Heath type set up that cuts parts out all day. No where as efficient as a CNC but heck of a lot cheaper.

PTSideshow
01-09-2010, 06:07 AM
Here is the place to go for that kind of thing.
A plasma CNC type forum (http://www.plasmaspider.com/)
:D

Mark McGrath
01-09-2010, 06:44 AM
Esab still sells bug-eye burners and they can be used with plasma or oxy-fuel. No problems.
.

That`s because they are selling modern m/c`s with uprated drives and controls with plasma in mind.The older ones were not designed to be plasma compatible and therefore have much slower feedrates.
I have one here that I was contemplating uprating but bought a cnc plasma instead.

Black_Moons
01-09-2010, 07:47 AM
Woah thats an amazeing cutting picture...

What exactly is this magnetic head/magic eye stuff? Can I get a link explaining its operation? Id google it but those searchwords tend to bring up other results.

JoeFin
01-09-2010, 08:05 AM
The problem with using a template or magic eye oxy-acetylene profile for plasma is that very few of them,especially the older ones are capable of producing the cutting speeds plasma needs.
The main problem I see with a pantograph machine is the same.Will you be able to move the stylus fast enough to keep the plasma cutting and how smooth would the movement be?
Mark.

Being a direct 1:1 ratio would it need to be any faster then just cutting it out by hand? I was thinking I could move the air button over to the stylus and just follow the pattern by hand

I'm just looking to build a 1' x 2' sized machine to cut out patterns of up to .325" plate. Doesn't need to be any more accurate then .025". Most of the patterns have no straight lines in their geometry

Still a lot cheaper then contour cutting with end mills

davidfe
01-09-2010, 09:43 AM
Do you recall where the photo came from?

That is extremely interesting. Would love to see more about it.

Thanks,:)
David


Been toying with the idea of making Pantograph Plasma Cutter and was wondering if anyone has tried with any success so far.

Found this pic on the internet and the concept looks pretty good althou it would take so modification to apply it to a plasma cutter

http://i54.photobucket.com/albums/g119/eshuffle/Picture095.jpg

Any thoughts ?

Mark McGrath
01-09-2010, 02:35 PM
I'm just looking to build a 1' x 2' sized machine to cut out patterns of up to .325" plate. Doesn't need to be any more accurate then .025". Most of the patterns have no straight lines in their geometry



Joe,probably work.Depending upon how many amps you had you would have to go at between 2 and 8 feet/min on mild steel at 5/16" thick.
But,how do you watch what your doing with the template and how the cut is going bearing in mind you need eye protection and it will be kind of hot close up.
I did consider just mounting a torch on the end of a long arm which was bolted to the table of a cnc mill.Probably have worked fine for small parts.
Mark.

doctor demo
01-09-2010, 03:16 PM
The problem with using a template or magic eye oxy-acetylene profile for plasma is that very few of them,especially the older ones are capable of producing the cutting speeds plasma needs.
The main problem I see with a pantograph machine is the same.Will you be able to move the stylus fast enough to keep the plasma cutting and how smooth would the movement be?
Mark.
No problem as far as speed goes, on My particular unit the drive shaft was 1/4'' and held in with a nut much like acutter in a router. I replaced the original with a 5/8'' drive wheel turned down to 1/4'' to fit as the original. On 3/8'' plate the speed controll is set just a little over half throtle, 1/8'' or thinner might be a problem but I don't do any plasma cutting on stuff that thin.

Steve

Dawai
01-09-2010, 03:26 PM
YES, it don't have to be as complicated as the router you show there. You could use ball bearing drawer slides for "that" type build. One of the guitar guys doing inlays did it with two sets of ball bearing drawer slides.. one x, one Y.. and a pivot.. Router and scribe on same plane.

FOR a Hotrod bracket maker that fits on a 55 gallon barrel, I have built one here laying on the table. I emailed George asking if he wanted me to write it up for HSM magazine. It cost almost $10 to build.

The nice thing about a pantograph is that you can rig the linkages up to allow extreme precision.. for example a 10x larger pattern.. you trace it.. and error is reduced by 10x also. For simplicity, the plasma pantograph is 1:1.
Mucho simpler..

Kinda strange there bud.. are ya reading my thoughts? Do I have to wear a tin foil hat??

Mark McGrath
01-09-2010, 04:10 PM
No problem as far as speed goes, on My particular unit the drive shaft was 1/4'' and held in with a nut much like acutter in a router. I replaced the original with a 5/8'' drive wheel turned down to 1/4'' to fit as the original. On 3/8'' plate the speed controll is set just a little over half throtle, 1/8'' or thinner might be a problem but I don't do any plasma cutting on stuff that thin.

Steve

When I said what I did,I based it on the fact that if you were building a plasma cutter you would want a speed range that would cover from thin up to the capacity of your power source.
For you to say "no problem as far as speed goes" and then come back and say it`s ok for 3/8" plate but thinner might be a bit of a problem,sort of makes your first statement pointless and backs up my original statement.
It`s like if you built a drilling or milling machine it would be pretty useless if it only had one speed.
Even the old cnc plasmas would run at 1000"/min for thin down to 10"/min for thick material.There is not a magnetic template follower ever been built that would run at these speeds without modification.

HarryG
01-09-2010, 05:07 PM
Got any pictures?

Not right now, unless you want look at it unassembled.

When I first built it (back in the '80's), I mounted it to the garage wall. Never once thought about pix then. I've since moved and am in the process of mounting it on my welding table.

When it was nearly complete, I found plans which a guy was selling and bought a set because I was having trouble with the pattern-follower. I think he's still selling plans, but I don't know whether he's upgraded them for plasma. If anyone's interested, I can post his contact info.

doctor demo
01-09-2010, 05:29 PM
When I said what I did,I based it on the fact that if you were building a plasma cutter you would want a speed range that would cover from thin up to the capacity of your power source.
For you to say "no problem as far as speed goes" and then come back and say it`s ok for 3/8" plate but thinner might be a bit of a problem,sort of makes your first statement pointless and backs up my original statement.
It`s like if you built a drilling or milling machine it would be pretty useless if it only had one speed.
Even the old cnc plasmas would run at 1000"/min for thin down to 10"/min for thick material.There is not a magnetic template follower ever been built that would run at these speeds without modification.
Well Mark , speed isn't a problem for Me and My machine . Like I said , I don't do thin stuff. I have not checked the ipm of My machine but it works quite well for everything that I do between 1/4 and 1 inch with 1'' being the absolute limit.
"If You were building a plasma cutter you would want a speed range that would cover from thin up to the capacity of your power source."
No I don't want or need to cut thin material so I don't have a problem as far as speed goes.
It has more than a one speed mill or drill ,it has a speed range that works for My material use range.So it doesn't make My statement ''pointless''.

Steve

JoeFin
01-09-2010, 05:36 PM
Joe,probably work.Depending upon how many amps you had you would have to go at between 2 and 8 feet/min on mild steel at 5/16" thick.
But,how do you watch what your doing with the template and how the cut is going bearing in mind you need eye protection and it will be kind of hot close up.


I was thinking of modifying his approach to have the Stylus table up front and 6" elevated from the cutting table, which of course would be mounted 6" over a water reservoir to prevent Hot Cherries rolling all over the place. That way I could have 6" shields all around the cutting area.

Frankly I never thought about the Eye Protection aspect

BTW: it is a 50 amp plasma cutter rated to cut 3/4"

davidh
01-09-2010, 05:52 PM
is the sloped kirf problem not an issue any more ? i always get a sloped or slanted kirf if i just hold the torch in the same plain and go around a circle. more noticable of course as the material thickness increases. . . .