Snapped a new pic of the swivel coupler goodies (ooooooh, shiny bronze bushings) and bag of pronged thread inserts (to be used in cabin floor for hidden bolting to trailer frame) received from brown truck yesterday...
Up and out, java and a bagel on the fly to here to return the std coupler....
Also looked to see if they had any plain draw bar stock, or an inexpensive finished draw bar that I could cut to use for my swivel draw bar. Had thought about using solid 2 x 2 bar, as seen on other draw bars, but when I saw that a bunch of the class III (5000 lb.) hitches were made from SQ Tube slightly less than 1/4 inch thk, I decided to just use some of the 2 x 2 x 3/16 tube that I have left over from the tongue frame and front xmbr. A little out of sequence, but here's the draw bar blank I cut later. The end to be welded was descaled on the Bader belt sander. It will also get a close tolerance hole for the Reese tamperproof locking hitch pin that I already have for towing my small boat.
Then pilgramage to Fab Mecca (Metal Werks Shop), we woke up to about an inch or so of wet slushy snow Friday for a little surprise during the morning commute. Mostly gone now.
Got organized bringing in all my new goodies and laying out the latest plan prints. Quick mock up of prototype pintle shaft and bronze bushings...
When I measured the mounting pattern off of the std coupler for the tongue jack I must have been a 16th off on the location of the big hole for the jack cylinder. And when I was making it I just went right ahead and worked to my measurements, rather than cutting the big hole first, going out to my car to get the jack, and templating the bolt hole pattern to make sure everything was good. Needed to use this
the electric die grinder with a rotary file to nip a little fish mouth in each of the two rear bolt slots of the tongue jack.
Clamped the jack mounting plate (made yesterday in previous post) to the bench to check fit.
All better now. (The callout on the prints has been changed to specify templating the bolt pattern.)
Then out front to Karl's old shop, the 3 season front porch, to grab that extra stick of 2x2x1/8 wall SQ TB. Tons of steel have passed through this little door over the years leading up to building the big barn. (Technically the barn is classified by building and zoning as a "shed"...building permit guy, "You gonna put animals in that barn?" Karl, "Nope." Permit guy, "Then it's a shed.") Biggest damn shed I've ever seen! People, it's a barn.
Old shop.
Inside old shop.
The metal framework pieces attahched along the left wall support the under bench steel storage rack, the bench top, and the upper shelf braces (planks now removed) all the way down to the concrete floor. The upper shelf used to be loaded up with all of Karl's cased power tools. The two big steel plates (that are now the castered layout tables in the big barn) were mounted on a square tube frame base that used to be in front of the windows on the right. The milling machine and lathe were down at the other end. It was long and narrow, but very well thought out. Ideal shop for making architectural decorative hand railings. Bigger stuff was done right out in front of the door in the previous pic.
Back to the barn and cutting the rear xmbr to length.
Karl was all too happy to donate this drop piece of 2-3/8 round bar (center), in mild steel, for the redo of the swivel coupler pintle shaft and front xmber bushing sleeve. No 2 inch dia bar means a little more turning and waste, but the Fryer CNC lathe at work will just laugh a menacing laugh, boo-wah-ha-ha-ha and start spitting out chips.
Also notice the bars with holes in the background. Karl recently got a great deal on a whole auction lot of brand new precision machine track and gear rack. He is planning to make a CNC plasma cutting table that may also be able to be configured as a router table. (Although he has a plasma cutter, he currently farms out his CNC plasma and laser cutting work.) There is way more track and gear rack than he can use, so any surplus will be put back up for sale later.
We decided to keep knocking off the smaller bits and swivel coupler parts. It is all progress and this way we don't have the large trailer frame in our way just yet. We went through my list of bits and pieces that needed to be fabricated for the swivel coupler, the short piece of 2x3x3/16 rectangular tube for the tongue front xmber where the swivel pintle shaft goes, a couple of stray closure plates for tube ends, etc. Karl had some bits on hand and jumped right on the cellie for the rest.
Half an hour later, after working on some of the above, we jump in the car and run up the road a short hop to Mid City Steel....
Which is located just up the way from the kiln works where my wife Yvette throws potery for a hobby.
This mug...
...has a mug of it's own. One of her more whimsical pieces.
Here's what we got for steel today...
1 ft of 2 x 2 SQ Bar (need 4 inches) $15
1 ft of 2 x 3 x 3/16 Rect Tube (need 6-1/2 inches) $6
2 ft of 1/2 x 2 Flat Bar (need about 16 inches) $7, sub total $28
Previous steel order for main rails, xmbrs, and tongue;
24 ft of 2 x 2 x 3/16 Sq Tube, $73
24 ft of 2 x 2 x 1/8 Sq Tube, $52
20 ft of 2 x 2 x 1/8 angle (later swapped for 1-1/2 x 1-1/2 x 1/8), $23, subtotal $148
Total cash outlay for raw steel, not including scrounged items and at Karl's frequent flyer pricing with no mark up to me, $176.
Did I mention how greatful I am to have such a good friend in Karl? There is no way I could acheive the results I'm acheiveing, in the short time that it has taken me thus far, without his help and support.
Back at the barn I asked Karl where I could find a utility knife to cut the wrapper off of the steel bundle. He directs me to this...
Crocodile Dundee, "Now that's a utility knife." Old chef's knife that Karl picked up at a yard sale. Fairly abused.
I start to get organized, jotting cut lengths onto steel with a soap stone, and Karl started cutting. He's so quick that before you know it I'm done noodling and he's done cutting. Some of the results...
The 1/2 x 2 flat bar chunks will become the clevis', or yokes, for the swivel coupler U-joint. The short piece of 5/8 Rnd Bar will be the U-joint pin. Here's an isometric view of the U-Joint (picture taken of hard copy of the plan).
The pintle shaft will have a 3/4 inch nipple, or spigot, turned on the front end. (The alloy prototype of the pintle shaft was just left long for chucking and we didn't bother adding this feature before abandoning the alloy). This spigot will pilot and align into a hole in the back of the clevis yoke, ensuring a nice accurate central axis and giving a place for a plug weld in the hub of the yoke, in addition to the full circle weld on the back side. So Karl used the iron worker to punch the big hole in the half inch thick blank (seen in above pic). The force of punching such a big hole in such a short work piece put quite a curl into it; perhaps 1/8 inch in 2-1/2 length. So Karl used the brake press feature on the back of the iron worker, with some big blocks of steel used as flat mandrels to squash it back flat again. I was deburring parts on the Bader belt sander at the time and missed the photo op, but you can see the yellow square opening in the center of the iron worker frame in this older pic. I believe Karl said it had 16000 lbs of force.
The U-Joint will have the bronze sleeve bushings (shown earlier) pressed in. It will have a double nutted 5/8 grade 5 bolt with safety retaining pin at the hitch draw bar end (that can be removed for easier coupling to the TV, not sure what to do about theft securety yet) and a fixed pin at the swivel pintle shaft end that will be retained by welded keeper collars or buttons. Karl went to work drilling out some 1-1/4 Rnd Bar to the pin size of 5/8 inch for the pin keepers.
Pic of Karl's lathe.
(Notice the raised steel craddle that it is sitting on. This allows him to move it around with his fork truck, pallet jack or Allis Chalmers tractor equiped with forks in lieu of loader bucket. A lot of his heavy machinery is mounted this way. This gives him maximum flexibilty with his shop configuration. He can, has, and will reconfigure the whole shop to suit specific large jobs that call for processing large quantities of materials with the most efficiency.)
1-1/4 Rnd Bar, for pin keepers, chucked in lathe...
Center drilling keeper stock in lathe...
Note recirculating coolant (copper tube by cutter).
I had Karl touch off on the end with a larger drill bit to give a little weld prep and a little deeper weld penetration when the keepers are welded to the pin at assembly, before parting each of them off on the cut off saw. Mock up of pin and keepers shown here...
Meanwhile, I was laying out and miter cutting the box tubing for the little front xmbr where the swivel pintle shaft mounts.
First miter cut...
Second miter cut...
Mitered xmbr tube blank with (now abandoned alloy, to be replaced with mild steel) swivel pintle sleeve blank...
Karl just recently moved the lathe and milling machine from the old shop to the barn, so all of his tooling was still packed in boxes.
Looking for the 2 inch slugger bit and holder found 2 inch twist bit...
Nope.
Ah, there it is. Setting up the slugger bit...
Close up of slugger bit...
A bit more accurate than a wobbly tin hole saw, ya think? The pointy pin in the center allows you to align precisely to your prick punch marks and is spring loaded to eject the slug automaticly.
Karl's milling machine...
Swivel xmbr blank on parallels in mill vise...
No pics of the slugger cutting, I was manning the coolant squeeze bottle and it went thru so much faster than a hole saw, throwing chips madly, that I had no time to take a pic. Also seem to have lost both still photos showing the near side hole with slug, and the follow up far side hole while still in the mill, but here is a shot of the xmbr on the plans with the (now abandoned alloy to be replaced with mild steel) blank for the swivel pintle shaft bushing sleeve that will be welded into this hole.
At some point we jumped in the car and went up the road a piece to the Hadlyme Country Store (deli and bakery) to grab a sandwich for lunch...
A stones through away is the Hadlyme Ferry slip, a small cable guided state run ferry that crosses the Connecticut River during summer months, located near Gillette's Castle (famous actor who played Sherlock Holmes, IIRC on Broadway), and historic Goodspeed Opera House. We pulled up to the river and ate lunch.
Mmmm, chicken salad with cranberries, walnuts, provalone, lettuce and chipped dill pickles on a fresh baked soft hard roll (not on diet plan!!!)...
(Gratuitous food porn.)
Back to Fab Mecca where we used the 2 x 2 Sq Bar x 4 inch long blank for the U-Joint, two of the 1/8 thk cap plates for the short pintle shaft xmbr (same thickness as the flanges on the bronze bushings that will be pressed into the ears of the yokes from the inside), and a couple of 0.010 thk shims made from aluminum flashing (clearance allowance) as a spacer. This all got clamped to the corner of the bench with the clevis yoke parts "square to the world" for welding. I had thought we might be able to form the clevis yokes in the iron worker, but it doesn't have the capacity and accuracy would have been more difficult, so we opted to build up the yokes using "cabinet corner" joints and full penetration welds.
Karl was pretty antsy to weld this up, and I was tempted to let him do it (critical welds, and all), but I also want to "own" this project for myself. As much help as I am getting from him, I still want to be able to say that, "I built it". If we were going to MIG weld this, no question, Karl would have gotten the nod. MIG welding can be deceiving because it goes so fast, it takes a keen eye and proper positioning to make sure that you can see the puddle the whole time so that you can make sure that you are "walking the puddle" and not just bridging over the root seam. We definitely wanted good penetration on that root pass so that there would be no voids in the full penetration weld (i.e. joint will be welded solid 100/ct thru the whole joint), so we decided to TIG weld the root (first pass). With TIG welding it is a bit slower than MIG, and the torch is lighter and easier to manipulate, so it is easier to keep an eye on the puddle. Plus with TIG you are in constant control of the heat range using a throttle like foot pedal, whereas with MIG you set the heat range in advance and have no real way to change it during a pass.
Once we decided to use the TIG and set that all up, it didn't make any sense to switch to the MIG for the fill in work, and that turned out to be a good decision.
Karl and I staged an impromptu contest that I had no chance of winning. He would TIG the root on one side, I would do the other side, and we would compare.
Here's Karl's root weld. Note the shiny color (silver, gold, blue and rainbow showing good heat control w/o overheating) how consitent in width it is, the beautiful "stack of nickels" row of puddles, and good penetration on both sides w/o undercutting. Perfect!!! I guess it's a "guy thing" to appreciate a fine weld like a fine wine.
This is the $25 bottle of Merlot with heavy foil seal and cork that grew on a tree.
And here's mine. Wholly acceptable. Not quite as consitent in width, slightly gray in color showing a bit more heat for good penetration (not too hot tho, so okay), decent "nickels", no undercutting. A fine weld, wholly acceptable... but not perfect. This is the $10-$15 bottle of Pinot or Shiraz with the rubber cork and thin foil or mylar seal.
(Sorry close up photo of my weld came out blurry...just the photo, not the weld!)
If your welds look like the cheap bagged wine in a cardboard box (not the newer ones that are starting to get a little better, so I am told), or worse, I highly suggest that you get a qualified welder to make your critical welds.
Here are some obligatory arc flash pics of me welding the multiple fill and cap passes. (Remember that it is not safe to look at the weld flash with the naked eye, which is why television and movie shots of welding always bug me...uninformed viewers might think it is okay to stare at the pretty blue light, but you will risk damage and blindness if you do. Camera does not reproduce the UV so it is safe, I believe.)
Note the torch lead/cooling lines draped around my shoulders so that I don't have to support the whole weight of the lead with my wrist (TIG welding 101).
And here it is after 3 or 4 sticks of 3/32 wire and more passes than I bothered to keep track of.
See the little gap at the spacer shim that has opened up?
In this pic you can see how all of the flat bar edges have been sanded clean on the Bader to remove any scale that might contaminate the weld. I made several extra passes past where I felt that it was structurally adequate, just to make sure that there is enough to allow sanding back to a nice smooth, stress riserless rounded surface (mostly for appearance sake, to be done later).
Interesting to note that the welder was set at close to 200 amps (if using full pedal), that the first passes were made at about 2/3 to 3/4 pedal, and that by the time I was finishing up, there was so much latent heat in the piece that I was only using about 1/8 to 1/4 pedal. Not easy to do with MIG, but intuitive for an experienced TIG welder. Also, even though this was clamped, the force of the shrinking filler metal (as it cools it shrinks) was enough to pull the clamp open leaving the yoke ears out of parallel by about 1/32 inch over their length. Karl squished it back in the iron worker. Then when we measured it we found that the yoke ears had actually sucked towards each other by about 15 thou, so we will be facing the insides of the ears slightly in the milling machine to get the dimensions back. The inside corners of the yoke ear to hub joint will be welded with a single TIG bead to fuse any remaining root opening and prevent any stress risers (to be done later). Also, the outside corners on the tips of the yoke ears will be machined round using a rotary table on the milling machine, so that it can articulate further.
And here's the small front xmbr mocked up with the semi finished alloy prototype pintle shaft, heavy nut (used as a thread gage, will use slotted nut with cotter pin at final assembly), and rough finish clevis.
Back home again to be greeted by Magdalene...
And Saphron...
Tomorrow I will take the day off from building; few small chores to do around the house, rest, and early super out with family to celebrate my Mother's birthday.
Night.
Advancing the “state of the art” ... trailer wise ... 
... 
It won't be long now.
