Archive through August 18, 2004

[mgonitzke]

Thanks Art I'll try that, it doesn't seem to matter if it's hot or cold, it won't work at all.

 

[still gt pulling with my turbo diesel 1782]

Matt,it'll only be about 2 to 2.5 p.s.i.. If ya choose to switch over to an electric fuel pump watch it so you get a low pressure pump to match this pressure. Anything over 5 psi will push gas past the needle valve in the carb and flood it. Later M18's used a diaphragm(pulse) pump that caused lots of headaches also,don't bother trying it. Just make life easy and use an electric fuel pump,your M18 will thank you. ;-)

(Message edited by jdiedrichs on August 19, 2004)

 

[pandrews]

Bryan I just trimmed my nipple down to 7/8 of an inch with the sawzall added some exhaust putty worked out nice. Thinking of adding a 45 degree angle on the end, to shoot the niose down to the ground ? will this effect the performance?

Paul

 

[jpatchett]

The engine on my 982 (onan 20hp) occasionally will lock up and will not restart. This has happened hot or cold. I have to remove the drive shaft/hydro cover and turn the engine over via the drive shaft and a pipe wrench. The only thing that I can think of is that the engine stopped at the point where one piston is TDS and the other is BDS. Does anyone have any thoughts on this?

Richard,
The plasma cut I see is fairly typical as far as slag build up. Knocks off easy with a chipping hammer. The speed you cut is basically dependant on current and material thickness. If you travel too fast the cutter will not completely get through the material and it can blow back up toward you, so watch out. 50 amps with 1/2 or less you should not have any problems. I have seen cleaner cuts but they were not by hand. The cutter was mounted on a feed unit, variable speed motor and worm gear drive. Straight cuts only.
Don't think I would use rubber as a template it might catch on fire. I use structural angle as a guide/straight edge, need the higher profile. It has to be set back away from the desired cut, because of the head on the cutter being 1.25 inches in diameter(or so). Therefore the distance away is half, 0.75 inches.

 

[dfrisk]

RICHARD C. - NICE Machine! I agree 100% with everything Jim P. says. I used My 625 last weekend a little. Except when running really thin gauge material (18-20 Ga or thinner) the book says to run them wide open. I find that the roughness of cut is mostly from My moving the torch or having varied the travel speed unless I use a straight edge as a guide. I prefer about 3/4" x 3/4" x 1/8" angle iron. My torch is probably the same as Yours and I offset the straight edge 1/4" from the cut line. I hit the slag with my 4-1/2" angle grinder on the bottom side and a quick pass down the cut edge and I'm done. The book specified air PSI in BARS, and I think Mine recommends around 62 psi. Buy a spare nozzle and a couple spare electrodes. The electrodes don't last a real long time. When the torch starts to flame-out during a cut it's time to replace the electrode! Far as heat buildup in the cut pieces the thicker mat'l the slower the travel speed and the hotter they will get. Try slicing thru some 16 Ga. and it's about like slicing thru wet newspaper. You can touch the cut edge as soon as You can put the torch down & take off Your gloves! Watch out when You use it to keep all the cords, cables, & hoses up off the floor and away from the sparks & flying metal. I can't wait to see some of the projects You come up with to be able to use that thing!

 

[stanner]

A guy just sent me these pics, since there are some bike guys on the site, and the machine has a kubota d-1102 (Cub-bota)(to keep it kinda on topic), and it is a 'Hydro', i thought someone would enjoy it...

 

[aaytay]

Scott-
That looks like a bike Dunham would ride...
;-)

Question for slanty-grill owners:
I bought a Cub 73 in July that had a square (10hp style) gas tank on it with some worn looking "7hp" decals on the ends.

Initially, I thought the tank was a homebrew upgrade, but found this 73 on epay last night.

Has anybody else seen this square style tank on a 73? Being that my 73 is very late in the serial number range, I'm wondering if it wasn't a mid model change as the last of the 7hp's rolled off the assembly line.

Any info would be appreciated..

(Message edited by aaytay on August 19, 2004)

 

[jegstad]

Richard C,

Plasma cutter tip/info. I was talking to a Miller rep at a show and he said that you want minimize starting and stopping the cut because that is what wears out the "consumables" - tips, etc. Apparently once the arc is going there is very little wear on the tip.

 

[rchristensen]

Appreciate the comments on the Plasma cutting. I will try more current and practice on the speed. The guy at the welding shop said not to use anything metal for a guide due to it conducting current, he recommended one of those wood yard sticks. I want something that I can clamp down, don't want to hold somethng close to the tip. My tips are narrow at the point and then increase in diameter up about 3/16 inches, so I can use something if it is only about 3/16 inch high. I have a bunch of steel beams that I want to cut bolt holes in so I need some kind of template for them.

 

[kmcconaughey]

When camping be sure to protect your tools from bears

 

[dfrisk]

Richard - Your tip must be different than mine. Mine has a round flat surface with four small milled notches maybe 3/32" wide & 1/8" deep in an "X" pattern that I can "Drag" on the material according to the book. The "Nose" of the tip is about 1/2" in dia. and 1/4" tall, then flares out to the 1 to 1-1/4" dia. that screws onto the fiberglass tube on the torch. Your torch may be setup more for machine cutting than mine where the torch gets clamped in a carriage.
I tried using some 1/4" thk underlayment plywood for templates with "Smokey" results.

 

[jkoenig]

Gord N

A worn out gasket in the fuel petcock caused my 126 to behave in a similar way. It would start and run for a little while and then die. Turns out the seal had worked its way upstream and wouldn't let fuel through properly.

My Kohler dealer blamed it on todays gas having alcohol. Alcy dries out fuel hose, seals and gaskets... The petcock/sediment bowl in question was only 2 years old when it happened.

Good luck with yours.

 

[mroxby]

This is for Richard C. I work for a metal building manufacturer (IT manager) and I myself know nothing about plasma cutting so I sent his question in an email to on of our manufacturing locations. Hopefully this helps Richard and anyone else! Thanks.


It appears that the problem causing his first two questions are related to how fast he's moving the plasma head. The slag on the bottom of the cut appears to be "low speed dross". There is low speed dross and high speed dross. Low speed dross is very difficult to remove, usually requiring a grinder. High speed dross is a flaky material that can usually be removed by scraping, or light chiseling with a sharp chisel. He needs to cut pretty much as fast as he can and have it keep cutting. Also, he wants to hold the torch so that the head is perpendicular to the direction of travel, or so that the "flame" leads slightly. Of course, if he's making bevel cuts, he can tilt the torch to do that. He should also be able to turn up the air pressure without causing any problem. The recommendation in the manual is probably a minimum, not a maximum. I'm thinking that the more air he has, the harder it will blow the metal out of the cut, making for a smoother cut with less dross. When he gets the cut right, he should find that he needs very little preparation for welding, especially if he bevel cuts thick material.

As far as the template goes, we actually use steel here. I couldn't tell from the pictures if the torch tip has a drag shield or not, but if it does, he can butt it up against other metal without effecting the cut.

Thick steel will get hot. After all, the flame is somewhere around 3000ºF. If he is cutting thin sheetmetal, he can expect much less heat, mostly because the thickness of the cut is much less when compared to the surface area, and it can't absorb as much of the heat of cutting. He will also cut much, much faster, keeping the heat down.

To recap: Cut faster, add more air (probably), and keep the torch head perpendicular to the direction of travel when possible.
Some other tips: Keep the lead out from under the cutting area. The hot metal _will_ penetrate the outer sheath of the lead, burn through air lines, and cause leaks. These will keep the cutter from functioning. Also, try to keep "pilot arc" time to a minimum (if the machine has that feature); it's hard on tips.

 

[mgonitzke]

Jim D.-

Thanks for the tip, do you have a brand that you'd reccomend? Or where I might find one?

 

[aaytay]

Matt-
From my post last night:
<blockquote><hr size=0><!-quote-!><font size=1>quote:</font>

. I ended up replacing the (expensive) mechanical fuel pump on my 1872 with a cheaper NAPA version [electric] that's wired to a switch on the dash.<!-/quote-!><hr size=0></blockquote>

If I remember correctly, I think it cost me around $30.

<font size="-2">BTW....I replaced the pump on Jim D's recommendation. Thanks Jim D!</font>

(Message edited by aaytay on August 19, 2004)

 

[jbliler]

With the plasma cutters one of the good tips is to use all of the air drier you can get. Have had trouble with moisture in the air leading to very early tip distruction. Workshop here swears by one of the filters that holds a roll of toilet paper to catch and trap all the nasty stuff in the air supply.
Your supply shop should have a leather wrap for the hoses. they are a real money saver in the long run.
Just wait untill one of your friends wants a hole in their chrome truck bumper for trailer hitch wiring. Really nice to work with. Very little chrome damage.

 

[thoffman]

Art,
I had a 73 with the square tank. It alos had the offset filler neck too. The tank appeared to be not as long and the 10hp. tank also.

 

[dkamp]

Richard- I second Mark's co-worker's comments, and Jerry's suggestions. I don't own a cutter, but used three units (one owned by a client's R&D facility) and two owned by friends, and in all circumstances, I had the luxury of having experienced operators to verify the setup and my technique.

The plasma cutter works in a similar, but different way from a cutting torch- where the torch has 'preheat' characteristics (spread location and bore) to warm the steel before getting to the 'cutting' bore (in the center), the plasma-cutter just has the electrode, and the air blowing over the arc. The arc's contact point on the steel really confines the heat, and the air's function is to 1) blow away the softening steel and 2) keep the electrode cold enough to minimize erosion.

By increasing the air pressure, the molten steel will be knocked clear of the parent before re-freezing, rather than oozing down the side and sticking to the edge.

Re. the hose cover- Besides burning the hose, the other thing which causes aggrivating damage to the PC is dropping the head, and breaking the ceramic electrode support/insulator. Keep a few spares on hand (they're $$!) and be very protective of that cutting head.

Re. the guide- I never worry about using a metallic or conductive guide, but I don't use the head of the PC like I use the head of a cutting torch- on the ESAB that I've been borrowing lately, I measure back a certain distance, and slide the HANDLE of the PC along my guide... and the guide is typically an inch or two back from the head... where wood or plastic isn't normally at risk of catching fire... much... If your cutter head doesn't have a 'drag shield', see if one was available as an accessory. If not, MAKE one... they're hard to beat when you hafta make a complicated cut at arm's-length reach, and your cuts don't end up with unintended 'bevel'.

 

[aaytay]

Tom-
Thanks for the feedback on that 73 tank.

 

[sblunier]

Here's an odd-ball question, but I know SOMEBODY has a tractor like this.......

Is anyone running an xx8/9 series tractor with a Quiet Line ring gear start engine (here's the kicker)AND a mechanical PTO???????? Are there any clearance probelms with the PTO linkage (rod) and the starter?????