Man, with this damn bumper build, have I been dogging it or what?  Here is a post showing just how little I have done over the last few months.
I have the actual bumper more or less in the shape I want it. So I went on to building the swing away tire carrier. I drilled a hole through the driver’s side corner and welded in a section of aluminum tubing.
On the top surface I ground things down flush. What I haven’t shown is the heavy duty bracing I did to the bumper in this area.
Skipping ahead (too lazy to rearrange how the pics were inserted), making Delrin bushings.
The shaft is a bit of 1″ stainless rod let into a bit of 1/2″ stainless plate, welded to rod on top surface.
End of rod drilled and tapped 1/2″ nc.
Bushing for top of tube.
Bottom bushing is similar to top bushing but has a smaller flange. Here is top bushing being inserted into tube. The fit on the stainless shaft was a nice sliding fit, but the fit into the tube was tight. This resulted in the shaft having a very tight fit into the installed bushings, too tight really, so I had to take shaft out and take off a couple of thousands (inch).
Oh here we have the bottom bushing being inserted.
Just to be clear, this shows how the bushings fit on the shaft.
Skipping ahead again… today I offered up the bumper to the van. Bear in mind the bumper is sitting on the stock bumper mounts. I will be making new mounts which will move the bumper closer to the van by about 1.5″. Please keep that in mind when you look at the pictures, it is important.
You can see the swing away arm installed. More on that arm further down. But right now see how the arm hits the bumper? I did machine things so that the mounting surface was parallel to the arm so either the bumper has a curve or the tube welded into the bumper was not 90 degrees to the bumper top surface. I think the latter is correct. I will mill the arm mounting surface to correct this.
I’m liking the shape of the bumper more and more. I wasn’t pleased at first, but I think it is ok. If i had to quibble I would say the end caps are too thick. That’s Lily, one of our two dogs, looking very bored with what is going on.
Ok, time to explain the arm. I had some water jet off-cuts, 1/4″ 6061 aluminum, that had curved ends. And the ends matched the radius of the stainless disk welded to the shaft in the bumper. I cut the off-cuts to fit inside the arm and ground down the ends to extend the radius around. I then stacked and inserted into the arm (2″ box, 1/4″ wall, 6061 aluminum) and welded them up. Then I drilled 3 holes for 12mm cap head bolts and threaded 3 holes on the stainless disk to match. I’ll try and remember to get some pics of the end for the next update.
Now to determine where the upright should be positioned on the arm. I used and old bike wheel (25″ diameter) to help me decide. Now remember the bumper is sitting further out than its final position. So if I welded things up as shown, the upright would hit the hatch.
Figuring out the lateral position. Have to avoid the tail light.
And have to make sure there is clearance when arm swung out to the side. Too close here.
So moved the upright inboard about an inch.
Better clearance when swung out.
But still too close to hatch.
That means relocating the upright to the rear face of the arm. Not as tidy hand will mean some re-thinking of my latch/arm securing set up.
All for now, Â I really have to make the bumper mounts and do final welding of the trailer hitch sub assembly (which is hidden inside the bumper). That sub assembly will provide more support to the bumper – I’ll be screwing the aluminum down hard to it.
shooftie 
#1 by Jeff Vickers on February 12, 2014 - 11:11 pm
Looking good, Alistair. What’s your plan for the arm contacting the bumper under the weight of the spare? I have the GoWesty bumpers and spare tire swing-away and I like their simple solution: they drilled three holes in a small triangle in the bumper directly below the swing-away and popped 3 Delrin “buttons” into the bumper. So instead of the swing-away resting on the bumper, it rests on the three replaceable buttons. Spare tires are HEAVY! I can send you a pic if you’re interested.
Jeff
#2 by albell on February 12, 2014 - 11:25 pm
Hi Jeff,
I’d like to see the GW set up. I haven’t finished thinking about what I will do. Been mulling over a few ideas. What I do know is that I will have a vertical back stop welded to the bumper that the upright of the tire carrier will be pressed against. This back stop will have its height limited by the hatch opening. My trial fit today shows that I need to add a scab section onto the back of the upright if I weld the upright to the rear face of the arm. The scab piece will be the part contacting the back stop
I was thinking of a delrin pad, maybe tapered, on the top face of the bumper. Same idea as the GW buttons.
And the latch… Well I’m thinking of something that will incorporate a tapered pin so that the arm is located firmly. But I admit I don’t have it thought through. Yes, the tire will put a lot of strain on the arm, I want the locator/draw latch to very strong.
Don’t forget that the top surface of the bumper will be bolted down hard onto the thick walled steel tubing (box section) that runs between the mounts and that has the receiver hitch in the middle.
Boy, I sure can’t form a coherent paragraph sometimes.
Cheers,
Alistair
#3 by edbee on February 12, 2014 - 11:44 pm
Nice as usual! I like the shape of the bumper too. What about instead of welding the upright on the rear face of the arm, could you just angle the bottom of the upright a few degrees so when it sits on the top of the arm, the top of the upright is further ‘back’ than the bottom of the upright? (did that make sense?)
#4 by albell on February 13, 2014 - 9:06 am
Ed,
yes, I understand. infact I’m thinking about cutting up the upright and putting in a couple of bends to mirror the profile of the rear of the van. I’ll have to mock it up to see if it would work and if it looks daft or not.
cheers
ab
#5 by brady horrace on February 13, 2014 - 3:52 am
This is the same type or mount I made on my home made rear bumper. I set it up with mounts to accept swingaways on either side of the bumper. The Drivers has the tire swing away, the other side is my grill / whatever swing away. I used a premade pviot point which is basically a trailer wheel hub and axle without the hub and a sub axle. Looks good and it should work well.
#6 by famillysyncro on February 13, 2014 - 5:26 am
Love it, looks very good. Do you take Paypal?
#7 by albell on February 13, 2014 - 9:08 am
Aww, Jerome, you can do better than my effort. When it is finished I’ll send you rough dimensions to get you started and maybe suggestions what NOT to do. I have loads of those 🙂
cheers
ab
#8 by famillysyncro on February 13, 2014 - 5:06 pm
You are too modest Alistair….
Do you remember mine? You did machine a shaft and bushing for the swing arm, I took a piece a square tubing and a piece of rod to make it….. I know, I am really lazy….. 😉 but, I got 2 grease fittings on mine…..
You might not need to send me stuff for it, we might be able to come and visite the Island this year…. well, we’ll try to make it happen!
Keep up the good job.
Jerome
#9 by albell on February 13, 2014 - 6:52 pm
Jerome,
I do what I do for a few reasons. First because I like the doing almost more than the result. Sort of like the travelling rather than the destination. Second because I’m often unsure and insecure about how things will turn out and I ma easy prey to advice and suggestions about things being not strong enough. So I tend to over think my projects. The tire carrier is a good example. It is a fun project and has just enough problems or challenges that I don’t feel bored but yet still feel I can do it. And the stories I hear about rattling carriers makes me want to make the damn thing secure.
That last sentence is apropos to the latch mechanism I have in mind. It probably is unnecessary and might not work, but I have this tapered pin and socket idea I want to try out.
It would be great if you visited the island. If you have a choice I’d recommend August as the weather is almost guaranteed warm and dry.
cheers
ab
#10 by Pz on February 14, 2014 - 1:47 pm
Looking good Alistair!
I like the shape too.
Looks like it belongs.
Pz
#11 by albell on February 14, 2014 - 6:13 pm
Hey Phil, thanks!
I tired to make the bumper slim and close to the dimensions of the stock one. I don’t like a blocky looking bumper or one with a big overhang. GW plate bumpers are a good example of, in my eyes, a clumsy look. That being said I now know how hard it is to get a shape that looks right.
Cheers
Ab
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