Making tubing

[KeithB]

We make a product for one of our customers out of low carbon steel that is 1-3/4" OD, 6" long, and has a wall thickness of about 1/8". The last time we ran these we used 1.75" OD x 1.25" ID steel tubing. The lowest price I could find locally was $519 for a 20' stick. The price for 1.75" solid rod was $169. A price difference of $350 for about 1/2 of the material! This is exactly why I wanted to buy a big powerful drill press.

After cutting the material to length (6-3/8" long to allow for finishing to length) Scott faced the ends to clean up and put a center drill spot to start the drill point.

The drill pictured is a 1.281" spade drill. It does not need a lead drill like a large twist drill would require, it drills best in solid material. Big Mutha is rated to drill a 2" hole in solid steel so there was no problem with a 1-7/32" hole.

I was running it at 156 RPM and 0.009"/rev feedrate. To minimize runout I drilled in halfway from each end. Even with the extra handling time it only took 6-7 minutes apiece to drill out.

By the way, our customer was real happy when I told him we would charge him half the price difference so we could both come out ahead.

Big Mutha the drill press. (The picture is a little distorted.)


Spade drill for metal


Drilling the solid to make tubing. Note the chips - unlke twist drill a spade drill breaks up the chips and makes them easy to clean up.


A drilled out tube and the solid rod raw material.

 

[fiver]

wouldn't take long to fill a drum with scrap chips like that.

 

[smokeywolf]

I'm guessing that after tooling, electricity, labor and all the other ancillary expenses, you still came out ahead doing it that way.

What did we do before we had insert tooling? With built-in chip breakers.

I really do like your drill press.

 

[Bret4207]

Smokey- we went slower and learned how to sharpen drill bits right!!!

Nice job Keith!

 

[Joshua]

It’s too bad that this part couldn’t just be made with 1.75” x .120” DOM tubing. I just looked around and found it for about ten dollars a foot. Does the bore of this part need to be perfectly symmetrical, or do the ends just need to be square to each other?

That is a great drill press! We have an old Cincinnati/Bickford here that is capable of the same type of drilling. Cool stuff.

 

[KeithB]

The OD of the final product can be left unmachined, there are seven small tabs that get welded to it in various places. The ID has two different size bores, one slightly over 1.5”, one slightly under 1.5”. The DOM tubing used for previous batches had a 1/4” wall thickness, 1/8” would be too thin.

The product is a landing gear leg clamp. it is used to clamp the gear leg of a kit built aircraft to the socket that has the axle for the front wheel. One of the tabs is designed for a drill bushing. The kit builders line up the wheels to point straight and then drill a hole to bolt the socket to the gear leg. The clamp lets them do this with the wheels on the ground under full load.

You only need to use them once, and our customer will buy them back from their customers minus a rental fee, but nobody sends them back.

Like to know where you got that price. Is that with shipping?

 

[KeithB]

Here is a couple screen shots of the product.

 

[Joshua]

I mostly have used DOM tubing back when I was fabricating custom marine refrigeration systems.

But a lot a folks use this stuff to build roll cages, bumpers, and dune buggy frames.

You can find it often cheaper from these “off road” distributors because they have to compete against each other for the lowest price point. Grainger sure doesn’t sell it that cheap. Price doesn’t include shipping.

DOM Tube, 1.75" X .120" Wall, 1.5" Tube ID

Check out the deal on DOM Tube, 1.75" X .120" Wall, 1.5" Tube ID at RuffStuff Specialties

www.ruffstuffspecialties.com

 

[KeithB]

I checked your link - thanks by the way - and the tubing I use is $104.76 for 72". Buying it in such short lengths increases the scrap, and I would have to buy four pieces (24 feet) to get the same number of parts. That makes it $419 before shipping. Adding shipping would get it real close to the $519 my vendor quoted me, and they would deliver to me the next day.

That's what I've run into before in ordering from places like Online Metals (and others) that will only sell short lengths. If you only need a few feet its cheaper to get it online than to buy 20 feet you don't need, but that's rarely the case with us. There are three vendors in town here that will deliver to us at no charge and in full lengths - 12 ft for some stuff, 20 and 24 ft for other stuff, depending on what it is. We are set up now to safely handle long material.

I have ordered metal online for jobs I know I'll never see again - most .gov stuff is one-time work - but if I know I'll get a repeat order I'll buy a full length even if I won't use it all right away.

 

[KeithB]

Ian, the upper and lower gearbox use ISO 220 (Shell Vitrea 72, no longer made but Shell has a newer version that is recommended and available), there are filler holes to add the oil. But there are also oil nipples in several places that need the same oil, that was why I was looking for an oil gun.

(BTW - Vitrea 72 and its newer replacement are mineral oil based gear oil.)

 

[Ian]

The only oil gun I found was at McMaster-Carr. Would you post a photo of the nipples with a penny for reference?

 

[KeithB]

Sure, I’ll do that tomorrow when I go in. I can put a mike on them too. They look like a zerk fitting type but maybe a little larger. The manual calls them oil nipples. It’s a Brit machine. I may end up contacting the current NA distributor, I bet their service department has someone there that could help.

 

[KeithB]

Here is the lubrication plate. Note the distinction between "oil nipples" and "grease nipples".

 

[bruce381]

Those are old names from the past.
As I remember the Carnea was a MVI or mid viscosity index oil (napthienic I think) where the Virtea is / was I high viscosity index parafinic oil.
Both straight oils NO additives, cheapo oils for high loss low heat enviroments. Tho I think carnea was base oil used to make large diesel locomotives for a long time due to low ash formation and pre ignition.

 

[KeithB]

Glad they weren't expensive-o oils! I dropped $120 for a 5 gallon bucket! Still cheaper than ruining a $10k machine for lack of the proper oil..

 

[Joshua]

I was trying to cross reference lathe gear box oils recently. Most of our older equipment just has the type of oil paint penned above the oil fill plug.

The lathe that needed a bit of oil is our newer Czechoslovakian made one. No one had written on it yet, the manual was calling out modern oils, and our maintenance department hasn’t changed the names on our bulk oil containers that we use to top off machines since like probably the Eisenhower administration.

I finally tracked down one of the machine maintenance guys, he told me which oil to use, he confirmed that we had changed oil vendors and types of oil many times over the years but the names on our refill bottles hadn’t changed. They hadn’t changed our in-house names because they didn’t want to confuse the machine operators.

During our conversation he said something funny. He said that he had never seen a machine tool ruined by having the wrong oil put in it. But he had seen plenty ruined by running them empty. He then followed this up with the obligatory “you should always try to use the right oil” speech.

I once knew a guy who had been a bush mechanic up in Alaska. He had worked in logging and mining camps. He once told me a list of systems he had put 30 weight motor oil into. It was shocking to me, brake masters cylinders, hydraulic cylinders, rear end gear boxes. When I expressed my shock he just said “If a machine ain’t working, you ain’t making no money, and there ain’t no auto parts store within two hundred miles, so we did what worked!”

 

[KeithB]

Yes, in an emergency you do what needs to be done. Fortunately we could get the right oil.

Here is a couple shots of one of the oil nipples. It looks like a standard 1/4" zerk, The mike read 0.255".

LOL - I couldn't find a penny.

 

[KeithB]

Here is the way I take the cut off bits of steel and turn them into the tabs that will be welded on to the tube after its bored to size. I'm not a great welder so getting them to fit up as well as possible is a big help.

 

[Ian]

Buy a grease gun hose and zerk coupler for $10 at the autoparts store. Drill and Bore a piece of aluminum rod all but 3/8" through and polish. Outside thread the end and make a cap to screw onto it. Use all thread rod to make a leadscrew and drill/tap the cap through for it. Make a piston and turn a grove for an o-ring. Drill and tap the end of the tube for pipe threads to screw the hose fitting into. Weld a t-handle to the screw. Pour oil in it, insert piston, cap, and screw, hold upright and turn screw to purge air (like a hypodermic syringe), then apply to zerk and turn screw to inject oil. When empty, unthread the hose and blow the piston out with compressed air.

 

[KeithB]

That's a great description Ian, and if there was no reasonable cost alternative I'd probably do just that. But I found this so I think I'll buy myself an early Christmas present:

Heavy Duty Lever Action Oil Gun

Heay Duty Lever Action Oil Gun is designed with sealing elements that allow leak proof operation with oils and high-viscosity grease. Oil gun features a shock and rust-resistant polyamide barrel, air release valve, and aluminum head.

saeproducts.com