New Thule Trailer (4 Viewers)

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@Sir Velo hoping you might be able to take some more detailed pictures of your 80/20 rack set up. What I'm most interested in is:

  1. to see how you attached the 4 upright bars to the lid....some close ups of both the interior and exterior of the lid attachment points would be most desired. It also looks like the front and back attach differently as it looks like the frame under the lid is sloped, so I'd like to see both mounting points.
  2. What size bolts did you use to bolt the uprights to the lid? I'm assuming M6x1.00 or 1/4-20? If you have the lengths as we'll well that would be much appreciated also
  3. How is the 80/20 plate used to mount to the lid attached to the 80/20 bar? Did you use screw heads (counter sunk) that keep it flush with the plate so it sits flat against the lid?
  4. Looks like on the back upright there is a spacer needed on the upper two bolts. Do you have the length of that spacer handy?
 
@perkj I will gladly take some detailed photos and give a description of some of the aspects of the design and implementation. I will do this over the weekend and post here on Monday.

I can answer some of your questions from memory, most notably #3. So I thought about countersinking a proper screw but decided against it because I wasn't sure that my cutting on the material would adversely affect the material itself and cause weakness or a stress riser perhaps, so I just bolted it from the backside of the lid in the same fashion that theOz did with his welded plates.

Suffice it to say though, it was a bit of a PITA to bolt together the various pieces but I enjoy a challenge. Obviously, countersinking the plate and using a flathead screw would be advantageous in this regard since the plate and upright and now one fixed piece. Also I think I used a 1/4-20 or possibly a 5/16-24, I recall wanting some beefiness.

More on this later ;)
 
@perkj I have, I just haven't had the chance to put the details along with them together. I'm going to do that later this afternoon ;)
 
Alright, I think this should get the ball rolling @perkj ;) There should be enough in the pics to explain the overall design (I've also included some sketches with measurements that I used to flesh things out), I'll add some play by play and color commentary as required :)

Fwd-Bracket-Inside.jpg


5/16-32 bolts, the washer was needed on the middle top to compensate for length as I recall.

Aft-bracket-Inside.jpg

The middle hole is necessary in order to tighten the plate to the upright support member. I used helicopter tape to seal, I also got lazy with the silicone I guess, nothing on the 3 bottom bolts and I also forget the washer on that upper lefthand bolt :-/
Fwd-Bracket-Btm.jpg


1/4" spacers I believe.

Aft-Bracket-Top.jpg


The nylon spacers were cut from 1" parts and then filed a tad to accommodate the angle of the lid. The rubber gaskets while a good idea to seal, have now begun to perish in the sun and ozonated atmosphere of SoCal.

**Since I can only add 5 at the time I'll split this into 2 replies
 
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@Sir Velo thanks so much for the pictures and the details...exactly what I was hoping for. One question - for the front upright is there a clear difference in "sturdiness" given that its tied into the metal lid frame completely vs the rear where its tied into the frame with two of the bolts and then the plastic lid only with the other 2? I'm debating whether or not to mount both the front and the back the same (i.e. like the rear one in your picture) or to do exactly as you have done. I'm a stickler at times for preferring things to look even, however in this case completely get why you opted to tie both set of bolts into the frame in the front....just curious is there is indeed a sturdiness difference you can tell? I also noticed that the official Brenderup rack that someone posted earlier in this thread has both going half into the frame and half into the lid like our rear one...see picture below:


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Also my new tires arrived. I ended up going with Kenda Loadstar Karriers in a 175/80-13. These looked to have the most aggressive thread pattern (almost AT like) which I’m hoping will be helpful as a plan to use the trailer on some unpaved roads and mild trails. Ended up getting a good deal on them thru Walmart - $57 a piece & free shipping (vs $77 and free shipping from eTrailer and others). Still waiting for the new 13x4.5 rims to arrive from Germany.

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@perkj Good choice in rubber, I think my Carlise set may have a similar design but I plan on staying mostly on pavement (the Cervelo is what goes off road ;) )

So regarding the sturdiness of the front versus the rear, I can't rightly tell any difference and to be honest I bet one could get away with the 3 lower bolts, on the simple fact that the plate is 1/4" thick and the spacing of the mounting points is not spread out, but of course having the top bolted would reduce side to side flex. I also like symmetry to design, but I wanted to tie in all 6 on the front out of an abundance of caution even though I was well aware of the Brenderup design.

All in all it handled the 3 bikes well, and I also had my Thule hitch rack up top as well (which I won't bring this year as we'll stay in Yosemite - hopefully).
 
I decided to get the corners of the lid frame tied together today in prep for getting a rack mounted to it. Removing the lid is super easy (consists of removing the 2 hinge bolts and popping off the support lifts) and takes about 5 mins. I copied @Sir Velo 's method of tying the frame together, as oppose to @theOz 's method, though I will likely braces on the sides as well down the road to make it as stout as possible.

To start here is how @Sir Velo tied his frame together from the top of the frame:

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...and now here is how @theOz tied his frame from the side:

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Here are pictures from looking from both the bottom and top of the lid to show how I tied mine together:


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For those interested, here is the parts list from McMaster Carr for doing this:
  • L-Shape Flat-Surface Bracket with 5" Long Sides: McMaster-Carr
  • 18-8 Stainless Steel Phillips Flat Undercut Head Screws Passivated, 8-32 Thread Size, 5/8" Long: McMaster-Carr
  • 18-8 Stainless Steel Cap Nut 8-32 Thread Size: McMaster-Carr
  • 18-8 Stainless Steel Oversized Washer for Number 8 Screw Size, 0.172" ID, 0.5" OD: McMaster-Carr
 
@perkj Spot on!

For whatever reason I didn't use flathead screws (I want to say that I couldn't find any at HD, which is odd) and used panhead because I was impatient in getting the thing done. Doing so necessitated adding a rubber (likely vinyl composition) bumper to each corner of the rear lid as the screwheads rubbed into the top of the box, it also required that I re-position the lock. After all was said and done though I was happy that the lid felt more secure and wasn't rattling nearly as much. I also think the lid is pretty stout now, do you think the additional braces are necessary or just overkill?
 
@perkj Spot on!

For whatever reason I didn't use flathead screws (I want to say that I couldn't find any at HD, which is odd) and used panhead because I was impatient in getting the thing done. Doing so necessitated adding a rubber (likely vinyl composition) bumper to each corner of the rear lid as the screwheads rubbed into the top of the box, it also required that I re-position the lock. After all was said and done though I was happy that the lid felt more secure and wasn't rattling nearly as much. I also think the lid is pretty stout now, do you think the additional braces are necessary or just overkill?

@Sir Velo I definitely think the additional braces aren't necessary. Last night when I was measuring for what the additional bracket would need to be I realized that as it is now is extremely stout and doesn't need to be immediately addressed. I'll likely only add them if: (1) I find that after installing the rack and having weight on the rack I find that the frame begins to twist, distort or deflect in any way -OR- (2) I find myself really bored at some point and aching to do something....lol.

I would be very interested to see some pictures of the "bumpers" you added to the lid to prevent the lid for shifting at all, as well as how you repositioned the lock.

I did receive good news this morning that my shipment from Knott will be arriving today, which includes the new 4.5x13" rims along with a few sets of hub bearing and seals. Hopefully I be able to get the tires mounted on them this week. New fender are looking like they will arrive by mid-week as well. I ended up getting both sizes of fenders from trailer-fenders.com to be able to try both sizes out. I'll post some pictures as soon as everything is here and ready to install.
 
The new 13x4.5 rims arrived from Knott-Germany today with enough time for me to get them mounted as well. I must say Knott packed the rims and all of the other parts extremely well!
8421D038-4ABC-4248-8E3E-B0B53DF22A29.jpeg


To my surprised one sets of the fenders showed up as well from Trailer-Fenders.com . The "smaller" of the two I ordered arrived and these are the same length (front to back) as the stock trailers, but are 15mm wider (Black Plastic Universal Trailer Fender - 26" for 13 Inch Tires). As you'll see below they are a perfect match for the 175/80-13s. The mounting holes on the fenders lined right up with mount holes on the trailer and there was no need to do anything to them other than to bolt them to the trailer. No need to reposition the fenders in any way as @Sir Velo needed to do with the OEM stock fenders. The larger set of fenders are set to arrive on Wed and I'll test that one out on the other side of the trailer to see which I prefer, but right now I can say these are perfect.

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@perkj Nice! I've not yet ordered a rim from Knott, and have been on the fence with getting a fender from them. I just haven't had the chance to measure out the dimensions for the ones from Knott to determine if I'd like them or not (Knott?) since they are longer I think. The rim will work on my spindle though as it's about 55mm or so but not over 57mm.
 
@Sir Velo here are the dimensions (mm) of all of the fender options for fenders that look exactly like stock ones. I've also included the USD price for a PAIR (2) as well (based on currency conversions today). As you'll see, your cheapest bet is likely going to be getting the fenders from trailer-fenders.com unless the additional shipping cost to include the fenders with a rim purchase from Knott ends up being small. I can say that the trailer-fender.com fenders I received are made of the exact same material and look as those they came out of the same factory. Even all of the mounting holes were identical.

TrailerTek (they sell the "official" brenderup fenders):
  • Brenderup OEM/Stock: 185 (W) x 650 (L) - $55.80 plus shipping from UK
  • Brenderup 14” size: 200 (W) x 650 (L) - $62.80 plus shipping from UK
  • Brenderup 14”+ size: 230 (W) x 750 (L) - $62.80 plus shipping from UK

Knott (De Haan brand - these are the ones on the Knott site that look exactly like the Brenderup fenders. The "Knott" branded fenders are slightly different if you look closely):
  • Small: 180 (W) x 660 (L) - $42.44 plus shipping from Germany
  • Medium: 200 (W) x 660 (L) - $38.00 plus shipping from Germany
  • Large: 220 (W) x 750 (L) - $42.44 plus shipping from Germany

Trailer-Fenders.com (these are exactly like the Brenderup fenders)
  • Medium: 200 (W) x 660 (L) - $53.55 w/free shipping
  • Large: 220 (W) x 762 (L) - $57.60 w/free shipping
 
@perkj here's the bumpers I installed. I didn't put any at the front corners because it doesn't seem to present an issue.


IMG_0613.jpg


Note the damaged corner^^ I used JB Weld to repair the split that had traveled down the top edge of the lip.

IMG_0614.jpg
 
@Sir Velo thanks for the pictures of the bumper. Do you by chance recall the thickness of the bumper you used?

I've been thinking more about the rack. Two issues I've been grappling with are:
  1. I'm still a bit reluctant use the portion of the lid without the frame behind it as a mounting point for the rear upright as I'm nervous that a stress crack could develop at some point in time and I'd also like the option to remove the rack and not have holes in the upper portion of the lid.
  2. I'd prefer the ability to adjust the width between the front and rear uprights verses having that width be fixed.
My thought to address both of these issues is to run somewhere between 60" to 73" length of 80/20 15-Series 1.5x1.5 Extrusion (1515-S) down the side of the length of the lid where the lid is attached to the frame, utilizing the existing lid-to-frame bolts (though changing them to 5/16" bolts) to attached the 80/20 Extrusion to the lid side edge (may add some additional bolts along the run as well). This will give me a extrusion "track" to attach the uprights to and will allow for adjustability of the width of the uprights. This also will also remove the need for the mount points in the upper portion of the lid that doesn't have the frame behind it. It just so happens that the edge of the lid used to attach to the frame is exactly 1.5", the same as the 80/20 15-Series extrusion and thus should visually blend in with the lid extremely well. The frame behind the lid edge in the rear potion of the side lid frame is also 1.5". This should make for a very solid mount of the 80/20 extrusion and I'm really leaning towards this direction.

The picture below gives you a better visual of where I'd mount the 15-Series 1.5x1.5" extrusion track

0D5DB6EA-DCCC-4D45-AC39-3487808B599F.jpeg
 
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@perkj They're probably 1/4" or 3/8" I'd think.

This might be a really good way to go, it never occurred to me since I was biased by OEM design and didn't have a load of time to sort through ideas. I might have gone this route had this been presented, the nice thing about this is that you can test the overall design without too much change to the lid, so if it doesn't work as planned say, you can modify the design without much penalty (just heavier duty screws along the sides lol).
 
@Sir Velo looking deeper into the 80/20 site, they sell M5 threaded T-nuts for the 15 Series. It just so happens that McMasters sells stainless steel M5 bolts with grade 5 strength. My thought here is that rather than opening the holes in the frame to 5/16 (or M8), that I just go with M5 bolts and tee nuts and add 2 more holes to the frame in between the 3 they currently have. for the weight that the rack will see, I think multiple M5s at grade 5 strength will be sufficient. I believe the existing holes in the frame may accept M6 (or 1/4") bolts as well without having to bore them out. I'll use M6 if that is the case
 
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@Sir Velo here are some pictures of the larger fenders from trailer-fenders.com. I like their larger set better than the next size down that I posted previously. This set did arrive with a few gouges/blemishes in them...I made a quick call to trailer-fenders.com and they immediately sent me out a new set (due here this coming Wed) and told me to keep the ones with the blemishes. Great customer service! With theses larger fenders I did need to drill new holes in them to align with the existing holes in the trailer...simple to do using the original fender for the hole template. Have a look below:
483C5EB4-6A1A-4AEA-93B8-B2F665F55650.jpeg
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On another topic, I got all the parts ordered for the rack this weekend. Once the parts arrive I’ll post some pictures of what it looks like.
 
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