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View Full Version : Manual Pattern plasma, Special_Features. Circle_Cutter and Plasma_Saw


Dawai
09-17-2011, 10:21 AM
http://www.metalmeet.com/forum/picture.php?albumid=404&pictureid=5249
As it was about 10-15 years ago.. a barrel head tracer, pattern arm was cut off.. this one is paintline track, UNISTRUT, POWER STRUT would work as well as the paintline track to slide the pattern mount up and down. I leveled and welded a 8" x 1/2" plate on top of the mast head, then drilled a 1/2" hole in center end of pattern arm, and put second 8" plate under it, welded that to pattern ARM.. WElded a 1/2" nut to 1"x4" tube, welded cross bar onto it to convert to hand nut.

Save yourself some grief, level the table BEFORE you mount the mast, or anything else, use a 2 foot or longer level. I have rollers on one end, and a car scissor jack on the other. Hunting some all thread about 1" in diameter to make adjustable feet-legs..

As modified, gas torch demo'ed, mount made from old 1 3/8" rod from hyd cylinder, mounted gear rack on it, it slides up and down, end drilled both ends 1/2" holes, side drilled setscrews to lock shafts. Plasma torch mount, slit 1" tube in half turned 1/2 rod to fit end of mount, set angle so torch center right under tracing pointer top side and vertical LEVEL with table. This table used to be my bender mount for my model3 hyd bender. I made it strong and light.

Mast head, I mounted it three times before I was happy, finally came up with the adjustor in picture.. has 4 bolts to fasten it to the cutting table and 4 leveling bolts to adjust level of mast head. cantilever arms, All pivot points parallel with torch centerline and level with table.. (important) so when you swivel arms it follows without changing height or centerline of torch off pattern. I have a drawing on the arms for the swivels somewhere from all them years ago, it has .78" flanged OD 3/8" ID roller bearings in ends of 1" round tube and 3/8" threaded rod for swivel hinges.. the further apart they are the more stable they are. I bent them up with a conduit bender.

Cutting table is just "floor grate from steel supply".. COST a lot more than doing it with flatbar thou, I got the bill and choked, it was near $80 for that lil "drop" that they were going to scrap.. I called and told them about it and got some of their ear.

Special features..adjustable CIRCLE cutter, Incompleted as yet, the Slider is tig welded flat bar set to slide on 1" square tube, place a couple pieces of paper onto the square tube, clamp the flatbar and weld it.. it makes a perfect sliding fit. I tig welded a small piece of flat stock to the top to offset the pivot, the welded a 1/2" bolt to it, must be perfectly squared and level with table.. tack it and check.

Welded a nut into the end of the 12" square tube, Bolted a piece of angle on it, inserted threaded rod and nuts on both sides, tack welded them. Tack welded short angle onto slider, drilled hole for threaded rod, tacked a nut to it and threaded onto threaded rod, now to adjust CIRCLE turn threaded rod and it moves the slider up and down the 1x1 tube. Tack welded a pivot, 1" x 4" bar center drilled 1/2", side drilled for possible locking bolt.

Cut a pattern mount plate, a 3/8" x 4" long flat stock that just fits inside open c'channel and slides up and down, insert into pattern arm, mark center, center that and drill and tap 5/16ths holes. CUT top pattern mount 6"x4"x3/8". center drill two more 1"x4" round stocks with 1/2" holes. drill plate next to edges. HOLD to plate with bolts and tig weld.

BY inserting the inner plate into the pattern arm, sliding top pattern mount onto it and putting two 5/16ths bolts in, the mount can go up and down arm. INsert circle cutter bolt into 1"x4" mount on pattern mount, insert 1/2" round rod from torch carrier to swivel on circle cutter.. put locking bolt into torch carrier, check that all rotates easily before welding up solid all parts..

Will fabricate a circle cutter crank handle and cross drill it for mounting to the bolt welded to slider.

SPECIAL FEATURE: Plasma saw.. using a ball bearing drawer slide, tack welded to side of pattern arm, mount a flatbar onto outer of slide, tack weld a 1"x4" center drilled round tube to flatbar, insert 1/2" round stock from slider-round stock to torch carrier, loosen pattern arm, rotate to angle you want to slice metal at.. lock down, slide torch, it goes perfectly straight with pattern arm and cuts like a radial arm saw. No ripples in cut, perfect clean. knock slag off with chipping hammer. very little clean up of metal parts.

MOST all parts I make are combinations of radius and straight cuts.. having a ability to do pattern following also just makes me even happier, cut one out, insert 1/2" rod with 3/16ths end.. follow pattern bolted to pattern mount, torch follows.

As I diss it and paint it, I'll take more in depth pictures and get measurements.. my nikon camera has died.. using a polaroid movie camera that takes kinda blurry pics..

It works. if you can make improvements please pay the forum by posting them here.
Sorry if it all sounds confusing.. sleep study last night and I am wrecked.. I'll convert it all to AMERICAN english later.. or have someone interpert it.

oldgoaly
09-17-2011, 03:51 PM
Just thinking out loud here, my Cebora (1980's Italian made) has the push down then lift while holding down the on button. Does that make it a bad candidate for a torch table? It works well, even Joel said wow (nothing excites him) that cuts better than the one he has used in school. Thanks for taking the time to show how to build one. tt;)

Dawai
09-17-2011, 05:15 PM
Yes, a contact torch, lights when you push it down. THIS is a no-contact plasma cutter.. a Lotos cut50D. cheap consumables.. like $39 for a 250pc set.. This torch cost me around $300 at the door off ebay. I think they are more now.

Piercing with a plasma greatly reduces the consumable life. Any moisture in the air, that too.. or shorting out the tips overheat them. Drilling a hole to start in is a good idea.

wanna help? I need to come up with a spring loaded guide rod to "hook" torch to the tool. pull spring loaded pin, move torch to plasma saw. It'll mostly be used on them two.

I'll get all the measurements when I paint.. RIGHT NOW? I put a 41 chevy window crank on it to turn the circle cutter. had to turn a bar, turn the end, drill and tap the end, belt sand it near square, then file it square, then cross drill it for push split pins.. I made it's own carrier.. to slide on next to the pattern holder so I can leave it assembled.

This is like my hotrods, they will never ever be completely done. Always a new cam or carb, or..

This Old man is squeaking when he moves and ready for bed.

Dawai
09-18-2011, 08:26 AM
Mounted two welders, a stick and mig under a table to make room for this table in the shop. THE plasma is now mounted on top of the table. THE old torch I have mounted on the pattern cutter just sparks.. something gave way, tip or wire inside. (time for a repair or mount the other torch). the wire inside the cable is inside the air line.. that way them cheap rascals can "cool" it as it runs.. and they can use a smaller wire.. about a 10ga for 50 amps..

I have a pencil drawing of the rotator bearing for the pattern followers.. Spring loaded. THE problem is the torch, method is not great.. I am going to just use the hole for torch alignment and mount a constant bearing above it. Like it was with the oxy rig.

I'll try to get some more pictures of the saw rig.. it's just a drawer slide.. not complicated.. so I didn't think it was important.

oldgoaly
09-18-2011, 08:55 AM
the saw just sunk in.... straight cut or cut off, gotcha now!

Dawai
09-18-2011, 09:38 AM
Rotate the mast head for Sawing different angles TT.. except.. with three feet.. today I found out it is easy to make a error. with that much leverage you can move it while it is clamped down. .

I am keeping a c-clamp on it till I get some angle indexing bolt hole in both plates.. the bottom will have to be hand drilled.

Everything I do is a composite of radius and straight angle cuts. A plasma etch a sketch.

Dawai
09-23-2011, 09:44 AM
http://www.youtube.com/watch?v=o2CdusMRvkA

Here's a video of the helve and patter cutter

More pictures too