The Poet Creek Express - Foamie Hybrid

[KCStudly]

Now that I have the leaf springs in hand I was able to better understand the dimensions that Ruff Stuff had on their website, so I was able to place my order for spring hanger and related brackets.

I went back and revised the links in my post from Sat Mar 10, 2012 at 2:19pm to reflect the ordered parts. Turned out to be the 3 inch parts for the 2-1/2 inch springs because there are 1/4 inch worth of bushing flanges sticking out all around. They also said that if the shackles aren't the length I need they can do an exchange, no problem.

[KCStudly]

Very minor progress on Monday.

Drilled the draw bar which is to be welded to the front swivel coupling yoke.

I hope all you pic junkies appreciate that fact that I can squeeze four (would have been five) pics out of drilling a simple hole!!!

Layout.

Note the freshly sharpened pilot and 21/32 drill bits.

At the milling machine (glorified drill press) pilot drilling thru the first side.


Continued thru the second side.


The pic of the 21/32 size drilling did not come out (sorry, would have been 5 pics). 21/32 is a 'Free Fit' clearance hole for the std. 5/8 draw bar pin size... I want to minimize clunking so I chose a relatively tight clearance. I can confirm that the freshly sharpened drill bit made a nice clean chip off both flutes and resulted in a perfectly sized round hole with very little burr.

Deburred holes with deburring tool/knife.


Tuesday was standing commitment, so no thrash.

Tonight, Wednesday, I had to leave work a little early to go to Occupational Health Clinic to renew my respirator qualification. That broke things up enough that I was ill prepared to work tonight (left in a rush, forgot welding helmet and related safety gear, left grit blasted stock for stabilizer jack mounts behind, did not get chance to grit blast tongue box mounting tabs, yadda yadda). Karl was going to come pick up a used grit blast cabinet that I had salvaged from the scrap pile (the old used one that my work was going to throw out due to easier to buy a new one than to refurbish the old tired one...needs a metal patch in the collection box due to wet sand rusting out, new filter socks and a new grate, but otherwise perfectly serviceable...I got permission to take it instead of scrap).

Anyway, Karl had a job running thru the shop (an aluminum and glass panel railing...high end stuff) and begged off on the cabinet pickup. Since I was not very organized, I decided to put in my first request for 'TeardropTime' and decided to take tonight off.

Will do a little research for axle and good plywood suppliers in my region instead.

[KCStudly]

Forward progress!

Made the rear stabilizer jack mounting plates tonight.

Selected 3/16 x 4 flat bar, grit blasted to remove scale and provide tooth for paint, did some layout right on the piece and prick punched. Cut to length, deburred and radiused the 'open' corner on the Bader sander.


Did this twice, one is opposite hand.

The odd hole is for the rear corner cabin mount and two holes in a line are for the stabilizer jack. Now, the top of the plate will be flush with the top of the trailer frame. This matches the rest of the cabin mounting brackets and intermediate xmbr's, and places the folded up stabilizer jacks as high up under the frame as possible so that they will be somewhat hidden and mostly out of harms way (...well, not really as some portions will still be hanging down below the frame, but I really could see no way around this...best I could do). In this configuration there will be no room for a bolt head or wrench space above the mounting plate. Follow along for the solution.

Drilled pilot holes (pic failed) then 7/16 thru.


Then counter sunk the holes for the stabilizers.


Test fit the plain steel (unplated) flat head screws.


Checked them again in the flat.


A little test fit showing the flat washer and self locking nut.


And one showing the two opposite hand pieces together.


I put a stack of washers and a temporary nut on each screw in turn to hold them snug and straight (pic failed), then welded the heads of the screws all the way around.


Note that I also filled in the screwdriver slot in the head of the screws.

And here's one of them with the welds sanded flat.


And the pair after welding. Basically the screws became weld studs, only more secure.


Next I used a piece of 2x2 and the draw bar tubing to make a little mock-up of the rear corner of the frame (upside down on the edge of the bench).
Retracted and stowed in raised position.


I used temporary std finish nuts but you can see the self locking hardware there ready to go.

Flipped down.



And extended.


Just got confirmation that the Ruff Stuff suspension mounting hardware has shipped; should be here early next week.

All for tonight.

[GPW]

Details , details !!! Amazing how many go into a trailer build ... Not just some iron stuck together eh !!!

[KCStudly]

The devil is in the details. With transit time and a little bit of socializing with Karl, I had at least 4 hrs into these two little brackets, just in what is shown here; never mind noodling over the concept, mounting location, sourcing and prepping the stock, or actually welding them onto the frame (which will come later, probably on Sunday).

In my best James T. Kirk staccato voice, 'Must ..keep..thrashing. Must..keep..thrashing.'

Another thing I thought I might do is press the bushings into the swivel coupler and do the final milling to set the fit of the coupler U-Joint. However, that would require that I weld the forward clevis yoke on to the draw bar first. There is actually quite a bit of range (+/- 1 inch) in height adjustment that I can make just depending on how that clevis is welded on to the draw bar, so I think I will hold off on that for now and see where the suspension ends up once I start to get some weight built on to the trailer.

Trying to stay ahead of the fabrication steps with material sourcing and work sequence will take more attention very soon!

[pete42]

KC there is a fine line that shouldn't be crossed when grinding welds especially welded through bolts
and that is to grind off so much weld that it loses it's holding power.
I have found over the years leaving the bolt head and the weld without grinding
that it is stronger, it may not look as nice as a smooth ground one, but stronger.
I think you need the penertation between the bolt head and metal plate to make a strong weld.
I really enjoy reading your post like I said before it takes me back to my 41 years as a maintenance electrician
machine builder, so you keep buildin and posting and I'll keep admiring your work.


Pete

[KCStudly]

I appreciate your concern, Pete. You are absolutely correct. It is very easy for people to grind off too much of the structural portion of a weld in the search for a smooth finish, especially if their welds are not that good (porous from bad purge or too much heat, or cold wormy looking things sitting on top with poor penetration). This is also a common problem on outside corner welds and is frequently cautioned against in hot rod circles when making custom frames and/or boxing plates, so I'll take a second to share some additional thoughts on the matter in this application.

The beauty of the countersunk flat head screw is that all of the holding power of the bolt will still be passed thru the plate unaffected by the weld. If I had used a piece of threaded rod (or just a cut off bolt) in a straight hole, or even a tapped threaded hole, it would not have anywhere near the holding power.

So the weld is purely there to resist the installation running torque of the self locking nut, plus whatever torque telegraphs thru the bolt up to the point that (assuming the weld is weak and would allow the bolt to turn) the friction that would develop between the bolt face and hole is fully developed.

Now I am a big fan of weld penetration. I tend to weld a little on the hot side to make sure that I get good penetration. By carefully watching the weld puddle as it forms and walking the puddle along (instead of just waving the torch over the general area and blasting along merrily, which is not uncommon with home owner sized 110v MIG welders) I am able to be sure that I am getting good penetration. What I did not mention previously was that almost no filler material was used on the perimeter welds around the heads of the bolts; I merely fused the two pieces together with the TIG torch, so I know that I have good penetration. Based on the width of the weld area being about 1/4 inch, I'd say I have about 1/8 inch penetration. There was a little under cutting on the plate side in a couple of places where I inadvertently biased the heat to the bolt, so I went back with some filler in a few spots to fill that in.

After all of this, I also welded up the slots of the bolts. Given the depth of the slot and the full puddle size to fill that in, I would say that if I had only tack welded the bolts in by just welding at both ends of the slots, and even with just these, had ground those tacks smooth, there would still be enough weld to resist the assembly torque of the fastener. Remember, the joint strength still lies with the bolt and the counter sunk hole, not the weld.

So let's assume that I really want to reef theses nuts down, go whole hog and put say 30 lbs-ft of torque (torque table says 13 lbs-ft dry, plus about 5 lbs-ft for the nylon insert running, so 30 is overkill). The head of the bolt is 0.7 inch diameter, or 0.35 radius. So the rotational force attempting to shear the weld is (12 inch/ft / 0.35in) x 30 lbs-ft = 1028.5 lbs. Steel has a yield strength of 36000 psi. Using 2/3 of that for a SF of 1.5 we get 24000 psi. So rounding off I need at least 1030/24000 = 0.043 sq inch of weld. I think I definitely have that covered, but let's check and see.

Even if I only have 1/16 inch of penetration, the circumference of the bolt head is pi x 0.7 = 2.2 inch. So the weld cross sectional area can be assumed to be at least 1/16 x 2.2 = 0.137 sq inch, or about 3x more than needed, for a SF of at least 6 (more if we don't over torque).

Just to be clear for anyone just stopping in, as far as the other welds on my trailer frame are concerned, the critical structural welds at the tubing joints were either prepared by grinding bevels at least 60/ct of the wall thickness, were inside fillets, or were configured geometrically to include generous 'natural' weld prep areas. Only the weld filler built up above the structural aspect of selected externally visible welds was sanded back to flush.

Thanks for your concern Pete, and for giving me an excuse to show off some of my engineering experience.

Bottom line, have a qualified welder in your corner (or be damn sure that you are one)!

[KCStudly]

The postman rang once... and left this little nugget of joy on the front step.


If you are an ultra light fanatic, or Thrifty-o-holic, you may want to avert your eyes now...


Leaf spring hangers, shackle brackets, shackles, poly bushings, and spring U-bolt plates. Nice quality, but very definitely overkill in the strength department.


And not at all thrifty

The hangers and DOM bushing tubes are 1/4 thk, and the shackles and spring plates are 3/8 thk.

One thing is for sure, I will most likely never have a suspension failure due to abuse!!!

I will source some 9/16-12UNC Gr 8 bolts, washers and self locking nuts to go with these. The std. trailer stuff has knurled splines under the heads to keep the bolts from turning so that the relative suspension motion occurs at the bolt shaft-to-bushing ID surface, and not at the relatively thin shackle plate or front hanger side wall. If allowed to turn at the spring hanger or shackle it could under cut the bolt due to the higher point load at these locations, so I will weld some short lengths of key stock on the outside up against the bolt wrench flats. These little key stock tabs will act like anti-rotation stops for the bolts, but will not prevent the bolt from being removed, nor will any welding be performed on the bolts themselves (high grade bolts don't take kindly to that).

We're well on our way now. The plan is starting to come together.

[KCStudly]

Big day of welding.

Karl was pretty whooped from a big railing install yesterday, so after he helped me get the main frame box up on to the saw horses he cut out and left me to my own devices.

Here you can see how the corner weld inside the rear of the frame tubes prevents the stabilizer plates from fitting up tight.


Need to nip the corner of the plates a little on the sander to get them to snuggle up nicely. Also, as nice as the suspension parts are, they still have little nubs from where the laser cuts started and stopped, and some flaring at the edges of the bends. So a pile of parts (on left side of sander stand) needed to be run thru the Bader.


Here is a before and after of the rear shackle hangers. Although the pic is a little blurry, you can still see where I have removed the flare on the edges of the bends and ever so slightly rounded the corner of the angle cut.


And here is the pile of parts a few minutes later.


In this pic of the shackles you can see how I have sanded off all of the little serrated waves and scale from the laser cut, and chamfered the edges slightly.


And here you can see how knocking the inside corner off of the stabilizer plate has allowed it to snuggle up to the inside of the frame rail and rear xmbr.
Frame upside down, street side shown


Curb side


Pay no attention to the man behind the welding hood.


Street side Stabilizer Plate welded in from the bottom.


Curb side


Getting the weld all the way into the corner is a little tricky. You need to get the welding torch cup and filler wire all crammed in there and still need to be able to see the puddle at the same time...all w/o letting the molten blob of filler jump onto the tungsten electrode.

With that done I moved on to welding the intermediate xmbr's, but was having a little trouble with the vertical welds puddling out, so I decided to flip the frame up on its side to get the weld into the horizontal position.

Here's 'The Flux Capacitor'.


Karl lives in a residential neighborhood with single phase electrical power, only. Many of the industrial and commercial pieces of equipment he has, including the lifting hoists, require 3 phase power of various voltages. The Flux Capacitor is a 2-1/2 HP 3 phase motor and some transformer banks. By running the 3 ph motor off of single phase power you can pick up the other two phases that are generated from the motor, transform that to the voltage required and convert to the input power needed (at least that's how this non-electrically minded person understands it).

Bottom line is, in order to use the hoist you need to plug in the appropriate twist lock cord and 'push the green button'...Max.

Here I am flipping the frame up on its side.



I wasn't too sure if the frame would try to slide off of the horses during the flip, and being by myself I took the precaution of clamping some stock on either side of the frame rail to act as stop blocks. The center clamp was added once the frame was up on edge, just to keep things stable due to the dwell effect. (If I had the hoist cinched up tight the frame was light on the horses and wanted to move around; once I let off the hoist enough to put some weight back on the horses the frame wanted to flop a little one way or the other back onto the hoist. The clamps stabilized everything and the hoist strap was left on just in case.)


Here are a bunch of pics of the intermediate xmbr welds done in the flat this way. Note that all of the corners were wrapped. The power of TIG.


More...

[KCStudly]

Then I flipped the frame down right side up.


I still needed to weld all of the main frame joints on the top side. In a recent post I talked about weld prep and geometric configurations for good weld penetration. The next few photos attempt to show how the combination of beveling some of the tube end edges with a grinder, and the radius on the outside corners of the box tubing combine to make nice wide open grooves for good weld penetration. It is this deep penetration that allows me to safely grind these welds flat without compromising the strength of the weld.


This one really shows the gap between the back of the angle iron and the radius of the tube (from the shadow area all the way up to the flat on the box tube). All of that will be filled with weld.


In order to manage the heat buildup, I went around and welded the main tube joints first. Here are a couple of the welds.


Here I am starting to weld up the stabilizer plates from the top. In the first pic I have already welded one seam and am using a piece of aluminum plate as a trivet to keep from burning my gloved hand on the fresh weld while I move on to the other seam. You can also see where I did a little pickup welding on the back rear (vertical)...where I had joked about using body filler (...I tried to resist, honest).

Street side

Curb side


Curb side front.


Street side front.


And moving around to the tops of the cabin mounting clips and intermediate xmbr's.


So the reason I am sanding the tops is so that the floor of the cabin will sit on a flush flat surface. I suppose between the canvas, glue, black goo and frame sealant bedding compound that this little bit of raised weld would not amount to much of an issue, but why risk it? (Part of the disease is rationalizing!!!)

Curb side rear sanded.


Rear cabin mount sanded.


Street side rear sanded.


Intermediate xmbr sanded.


Curb side front sanded.


I didn't go crazy trying to fill in every last divot because none of the stuff on the top of the frame is going to show.

More...

[KCStudly]

Flipped it up on the other side to get the other ends of the intermediate xmbr's.


Flipped it back upside down (no pic).


Still needed to get the back side of the little front tongue xmbr so I clamped the tongue up on its side on the bench.


Really tough to get the welding arc to go where you want it to down in such a narrow opening.


About this time Karl had come back out and helped out by doing a little pickup on some undercutting that I got while doing this tough weld.

Then we set the tongue up on the main frame on the marks I had made previously, and started checking measurements. I had scribed center marks on the front and rear xmbr's and strung a string all the way from the rear past the front mark and on thru the pintle sleeve in the tongue, like this.
.

At first the tongue looked like it needed to be shifted toward the curb side by about 1/4 inch. This surprised me a bunch because the frame had been so true when we finished up last time, and the tongue had been laid out right on the frame, and cross braced. That's when we decided to check the main frame diagonals again and found that it was now out by 1/2 inch (or +/-1/4 inch per side). Checked the rear of the frame with the framing square, and sure enough, it was racked. Welding in the rear corner stabilizer plates with a temp corner brace only on one side must have allowed it to pull. So we set up the lifting slings around the long corners and pulled it with the big binder strap again, quite forcefully this time. When I let the strap loose to see where we were it went 'SPROIIIING'. And sure enough we had it back to within 1/32 inch on the diagonals. We were able to shift the tongue back most of the way to where I had my original marks and used the string to set up the centerline exactly (well, as close as we could judge given that the string itself was about 1/16 inch thick...I'd say it was spot on).

I started in welding the tongue to the main frame. Once I had some good fat tacks down in a few key locations I was able to remove the temporary brace and get it out of my way.


The three way weld at the back of the rock slider (main frame bottom, rock slider middle, and cap plate top all welded along this edge in one root pass, then a couple of more passes to blend in the contour.


Other side.


More.



Lots of heat and big 1/8 inch filler rod to fill the radius of the heavier square tubing equals burned gloves (note the tip of the index finger all shrunk up...the glove fingers were a little long for me and that part was hanging out in the danger zone).


While I was doing that, Karl jumped right in and pulled a wheel off of the Jeep to check back spacing and hub clearance against some Dexter axles we've had laying around (bought a lot of surplus dropped spindle 3500# units w/ elec. brakes when I worked at the leaf vacuum place and was building my car trailer). Allowed me to keep welding on the tongue and still get the info I will need to order rims and axle. Fortunately the wheels look like they will work fine on the trailer axle I will be ordering, so that is good...I can have matching wheels.

And here we are putting the assembly to bed for the night.


All for now. Off to bed.

[GPW]

Can’t recall a trailer FAB ever being this complete ...

[KCStudly]

Too much, ya think?
I suppose I could back off on some of the individual weld pics. I know that's a little overkill. But damn it (mock indignation ) you guys are all so pushy about your pic quotas (mock whining ).

I may be getting a little carried away. Sharon may just be right with her "Priceless" comment. I started a spread sheet today with my receipts and the chassis expenditure to date is right about $653. Of that $104 is for the coupling and a whopping $375 is for the heavy duty off road suspension (...and I don't even have my axle yet ).

Total expenditure so far, including the windows, is about $867.

I think I'm going to hold off on ordering the axle until I'm sure that I can get my galley countertop height where I want it with this suspension set up. I may need shorter shackles, or I may have to mount the upper shackle mount through the frame. All else fails I can go spring under or revert to one of the drop spindle axles in hand (but that would be kind of silly considering all of the money I have in the hardcore suspension ).

I shopped around a little and found relatively good pricing for the wheels and tires to match the Jeep, 31x10.5-15 Toyo Open Country A/T LT's on Teflon coated ARE ATX Mojaves, about $150 each tire and wheel, for a list of about $600 for the pair. Unfortunately the wheels are not currently available and the factory would not state when they would be; guess they need to fill the boat in China before they will know (company name is American Racing and apparently they farm out their manufacturing to China... ).

The wheels look like this, only they are 5 lug on 4-1/2.

[GPW]

KC, like the old saying ... “ It only costs 80% more to go First Class !!! “

[KCStudly]

I know, I know, I really don't mean to sound like I'm complaining.

I figured my budget for this project would be about half of the going rate to buy a nice manufactured or first quality homebuilt TD outright (...even on the used market everyone seems to think that they never depreciate ...that is, until they are falling apart... so I know that the resale values are relatively strong), and I know (or at least hope that I know) that a big chunk of my budget will be due to splurging on the wheels and tires that I want. The suspension just sort of happened.

Spent some time today looking at options for 5 mm ply. After seeing Mike's problems with inexpensive non-waterproof luan underlayment, the marine grade Okoume doesn't look that steep at all, no sireee!

As with all of these things it seems that the experts and ready supply are always online, but with shipping and handling fees tagged on, whereas the local guy charges more, and if you're lucky has it in stock. The hardest thing seems to be figuring out where things are available locally, none of the mom & pop places have much info online. Guess I need to start dialling the phone. The thing I hate the most is when the local guy says, 'nope, don't have it, but I could order it for you'. Doh Uh, I can do that for myself, thank you.