Tip Top Tier Drop

[WizardOfOdds]

junkboy999 wrote ... You know. If you have a forward facing, center part that raises up, Kinda in reverse of what you did now. RTD-50 (R for reverse ) elevates 100% in front but only a few percent in the rear. like Sharon’s or the compact II. You and the misses could stand up full height. It would be like the pop-up on the A-liner but at a lower angle.

I was hoping to stir up this kind of thought! From your album, I see you do some independent thinking - I love it. Your drawing says it all, please leave it posted. I need to start using some sort of CAD tool, it is so good at putting an idea across.

When I first framed the TD50, I did not like the lack of head room in the front (unless I lowered the bed to a very low level), so I moved on. I considered a second roof somewhat like you show but only for the front half and that seemed to put too much weight front of the axle. I am sure your suggestion could be built. Theoretically it should not add much weight and (unlike my half roof) does not change the weight distribution very much.

I returned to the TD50 and raised the base side walls about 1.5 inches and made some other small changes to reach my headroom goal, but then I could only just barely see over the top, one of my most sacred goals. Since I can regain 2+ inches by moving the axle above the springs (future), I kept it and its been that way ever since. Eight trips later, I have to say I am satisfied with just about everything except 'over the top visibility'.

Keep up the original thinking, I Hope to hear from you more as things progress.

[Junkboy999]

Your trailer idea ( The 50%-100% ) reminds me of this trailer in this thread. The odssey sport travel trailer. Only forty of them were made 1962 - 1963.


There is a nice 1962 price is right show recorded on youtube. If you watch it , you will see a guy actually raises the front about a foot while the taller guy raises the back. I love how this ones opens. I would love to build a smaller version of this and pull it behind a 65 Ford Falcon on day when I hit the lotto.



please keep us posted on how it evolves and I few interior pictures would be nice.

[WizardOfOdds]

Crazy as it may seem, we decided to take the trailer as-is all the way from Virginia to Yellowstone and back through Montana and North Dakota. It was a wonderful trip which we will never forget. I put a few photos into the gallery.

Here is a short progress report on some of the previous discussion:

About the seal between tiers: My attempt at an indoor insect seal using a pie section of a pool noodle failed because I could not cut a slice as thin as the gap (which runs from nothing to about a quarter of an inch or so). However, we still did not have any real problem with insects. Even at Yellowstone where the mosquitoes were really dense (Canyon area), we had fewer in the camper than we did in the car. It just might be that mosquitoes don't crawl far and can't fly up a very narrow 4 inch vertical gap.

I also tried using a J-channel as a tire spray guard (driver side only). It worked well in the heavy rain we had through Ohio, but since I did not bother to paint it, it sticks out like a sore thumb, especially in the open configuration. Here it is in the closed ....
. I still intend to use an out-of-sight rubber seal between the tiers for any real build.

We had no trouble going up (or down) hills, not even over the Powder River Pass in Wyoming or those of I-68 in Western Maryland. All the work to keep the weight below 600 lbs paid off! Being able to see over the top of the trailer proved very valuable when backing into camp sites. The sight line down the center of the top was most helpful. I think the low closed profile (about 2/3 the height above the frame as a small 48" Tear Drop) was also helpful in managing drag, but a better aerodynamic shape would also help.

I never did quite master an easy way to 'make the bed'. When we camped with a pick up truck, we had access to both sides of the bed from the outside through two 54 inch long window doors (a bit like the bed access of a two door tear drop but at standing height). That made 'stretching the sheets' easy. Not so in small trailers or small tents! On the other hand, with the bed folded back, we had over half the total trailer foot print as 'open space' in front of a full width bench seat - much better than in our pickup.

I was going to try a foam roof, but figured it was safer to stick with the experimental tarp top (which proved as effective as the plywood top and a bit lighter) rather than leave on a 5300 mile trip with anything totally new. Just in case, I packed an extra roof (tarp) since it was light and it only takes a couple of hours to install. Although we had no trouble with wind or leaks, the tarp showed signs of surface deterioration by the end of the trip, especially near the seam. Some how I did not notice the tarp had a seam until it was almost fully installed. The metallic silver finish seems to slowly etch away leaving a white under surface (raw polypropylene?). I believe the erosion is etching or UV damage because the top does not flex or ripple even at highway speed. As of the end of the year (6+ months of constant outdoor exposure) the top still holds it's own against the rain, but I have to believe its only a matter of time.

Finally, one interesting and entertaining couple we met while camping told us we need to give this camper a name and then offered several very clever candidates that I will hold in reserve for when I do a real build. I selected the origin name "Tier Drop 50 Test Bed" because it was descriptive (upper tier drops over lower tier, a test platform to see if I could get satisfactory bed headroom in the open configuration while meeting my constraint to 'see-over-the-top' when closed, etc.). For now I have renamed it the "Tip Top Tier Drop".

[dodgedartgt]

Hi Wiz,

Sent you a PM an hour ago, without realizing you had made a post this week. Looking to hear back from you soon,

Mike in FL

[WizardOfOdds]

here is a portion of my reply to a request that others may find useful

I tried to make some measurements but am currently limited because I stored all my building materials and the like in the trailer for the winter. It would take quite a while to unpack and repack it all. However I was able to make some measurements without unpacking. You are right about the front overhang, it is six inches and gives us a nice 6 inch shelf at the end of the bed for overnight storage of glasses, water bottles, flashlights and the like. The bottom of the overhand is 14 inches above the bottom of the frame, but the hinge is a bit higher and covered up. The frame is about 3 inches high and my floor is a bit less than a half inch thick. The max interior head space is about 66 inches, tall enough for us to get out of bed or enter through the door without any head bangs. The nice part is that the peak is just where we wanted it (about midway between the end of the opened bed and the door. We find having the max height there is far more useful than if it were in the back or center of the trailer (that is max head room is best located for both getting out of bed and outside entry through a rear door).

[dodgedartgt]

Thnx Wiz!

Yes, I am interested, ready to start making sawdust as soon as I'm back on my "normal" (ha ha) schedule. I figured the peak height was before the foot of the bed, though I'd like to see something a bit taller inside. I guess I gotta get busy with "CAD", cardboard aided design... cut some scale profiles and see how they work together. I'd love to see more pics just as soon as you pull it from storage for use. But I know it ain't gonna happen this week... brrrrr

Mike in FL

[WizardOfOdds]

Hummm ... I guess using your jargon my CAD models were "Cardboard And Ducktape". They are a good idea especially if you use thick cardboard - I also used half inch thick foam - to avoid being fooled by folds that work only with very thin sheets. The problem is you never run out of new ideas to try. In a way the 'Testbed' is just a full size model to help make design decisions.

I find variable geometry (folding) designs much more challenging than any fixed geometry trailer - especially if the door needs to increase in height because it weakens the whole structure (more on this at the end). After years of drawings and models (paper, cardboard, foam and programs), all but the software 'line models' were tossed once I started experiments with the test bed. The line models ignore wall thickness (just like thin cardboard models), but you get a good idea of the major trades. If you are OK with vector algebra or trigonometry, it is possible to calculate the corners, roof vertex, headroom, door height and the like for both the open and closed configurations. I rely on my own calculations because I'm too lazy to learn any CAD, but it has limitations. Anyone know if any free CAD is useful for variable geometry designs? In particular, even if the line models of the open and closed configurations are consistent, you might not be able to move smoothly from one to the other (in some complicated designs)!

With this simple design it is easy to increase interior headroom, because for every inch you add to the closed height you get about two inches in head room! My problem was I made the ability to see over the top of the folded trailer (from the driver's seat of a small car) top priority. That made head room and door clearance a real challenge, but I still consider closed height at least as important as headroom as long as I don't bang my head on the top door jam or roof. We don't need more interior height, but I understand others may. When I get a reasonable tow vehicle, I may go a bit (not much) taller open and closed.

Also, moving the pivot has important impact. I was aiming to build the top as light (flimsy) as I could, so I picked the pivot to accommodate a fixed full back wall (to get maximum rigidity). This means the bottom rear lip of the top needs to fold down to the lower rear lip of the base. However, with the test bed I found the top I built to be stable enough without the full back and opted for making the lower portion of the rear wall removable. When erected, the back lower end panel was removed, turned 90 degrees and reinstalled as the door. It worked OK even though it was a bit wider than the door opening, but it looked a bit peculiar to see a sideways license plate on the door! Right now we just leave the lower panel at home and use a folding door. It might not be pretty, but it is convenient and light. I hope to consider some other options, but this brings me back to my point:

Toying with a 'test bed' told me things I could never learn from my models - like "will the top maintain shape while moving between configurations if I leave off the lower half of the rear wall?'. Yes, I could have 'over built' to make sure it does, but then I would have likely ended up heavy. I am really glad I decided to experiment with a 'testbed' before dropping a bundle of cash into my favorite design (which was not this one).

Given all the added complexity, I guess my conclusion is this: If a folding design does not provide at least a 50% increase in total interior volume AND at least 50% increase in headroom where you need it, try something else. Just my opinion -- others will place their values on other factors.

Have fun! - I did.

[dodgedartgt]

Hey Wiz, thnx for the thoughtful comments. Gives a lot of good food for thought. I do think I'll have an advantage in the interior lay-out over yours since I'm starting with a 76" wide (ex pop-up) trailer as a base. I do understand the need to see "over the top" as we have towed with both my wife's Intrepid and my Neon.
So, if the lower section rear panel is removeable, and left at home, does that me the aft end of the trailer is open (to some degree) when in the folded configuration? Not sure I completely picture what you're saying.

Mike in FL

[WizardOfOdds]

if the lower section rear panel is removeable, and left at home, does that me the aft end of the trailer is open (to some degree) when in the folded configuration?

No, the rear wall of the base closes the trailer in the travel position.

[cleburnescv1937]

Good ideas

[WizardOfOdds]

It’s been a long time since I updated this thread, but I’m very sorry to say that the Tip Top Tier Drop was destroyed in a highway accident in mid June when it was “back ended” while stopped in traffic. The collision not only took out the trailer, but also damaged the rear of my car and totaled the other car (I think it was a Mazda 626). It was a very sad end to an otherwise very good two day camp, the first (now also the last) of 2014.

In an unwanted twist of fate, the “testbed” gave up the ghost in an unplanned destructive test. The whole idea of the testbed was to see how light I could make things without being too flimsy. In the end it was the trailer frame and tongue which suffered the most damage, not the trailer body. I’ve seen complaints that the tongue of the HF 1700# is not beefy enough, but frankly I was glad that it collapsed the way it did because it probably saved our car (and us) a lot more damage.

I am not sure what I will do next, I’m not even convinced I will rebuild any time soon. I was planning to ‘take my time’ building the next trailer while using the Tip Top for camping. Although I could probably rebuild the old design rather quickly, that is not what I want to do with my time. I have no serious regrets other than the accident, but at my age it is becoming more important to do the camping than the building. The time I spent on the trailer building far exceeded the time I spent camping even including the 5300 mile trip last year. I doubt I will put more than minimal time and money into the next trailer because you never get back either if you suffer an accident, regardless of who is at fault. But don’t be surprised if you see a slightly updated Tip Top Tier Drop in the near future.

[dodgedartgt]

I'll be looking forward to seeing that "slightly updated Tip Top Tier Drop in the near future".
Glad you are okay and things weren't worse.

Mike in FL

[WizardOfOdds]

I rewrote this append several times trying to shorten it, but it has been well over a year since my last append and there is a lot I want to report.

Last year, two days after my last append, I decided to do a ‘hurry-up’ carbon copy of the Tip Top Tier Drop because I figured I had enough time to complete a duplicate before the camping season was over. I was dead wrong. I ran into a long series of unexpected problems with the frame (none of which were encountered with the 2006 kit).....

1- one of the wheels fit one side but not the other, so something was wrong with the axle.

2- the other wheel did not fit either side, so something was wrong with one of the wheels

3- the tongue arms did not align with the hold down brackets on the front cross member

4- the frame was warped diagonally from corner to corner (would not lie flat)

5- the axle could not be aligned (i.e. perpendicular to frame)

6- replacement parts I ordered the first week of Aug were slow in arriving (did not arrived until a few days before Christmas).

You can find the details in my posts in several threads of the “Trailer & Chassis Secrets” section, mostly in “A Tale of Two Trailers”http://www.tnttt.com/viewtopic.php?f=35&t=61451. Except for the axle & wheel issues, all the problems appeared to result from poor tolerances, like the difference between these two ‘identical’ tongue angle irons:



Finding the roots of these problems and developing work-arounds took a l-o-n-g time - ALL of Aug & Sept. I did not realize I had a warp problem until I had nearly finished the base half, so I had to disassemble it several times to figure out the cause. Although not totally conclusive, apparently bending the hold down brackets on the front cross member and force fitting the arms into them caused the warping. When trying to flatten the frame, it would only spring back or warp the opposite way. I was so discussed that I resolved to limit my losses by just finishing it as-is with what materials I had on hand.

It was almost done before I lost all hope of getting any camping in during the 2014 season, totally lost interest and did nothing more than install a thin temporary tarp roof for the winter.



This spring I replace that roof (nine months of sun caused deterioration along the tarp seam).



Lacking the heart to disassemble the whole thing to try removing the warp, I decided just to live with the embarrassment of driving around a lopsided eyesore rather than miss any more camping. So I call this trailer the Tip Top Tier Drop -- Pisa Edition (in honor of the famous leaning tower).

Despite my conviction to “change nothing” in order to save time, I could not resist the temptation to try a few modifications. I lowered the tail lights and reconfigured the framing to (slightly) increase the opened height (which led to more problems, but that’s another story). But the big change was to skin the base with foam and vinyl siding (which required adding braces) rather than plywood. I only cover (‘skin’) one side of the framing. On the original trailer the base used an internal frame while the top’s frame was external, leaving the two smooth skinned sides to slide upon each other. That worked really well, but I wanted to try vinyl and foam even knowing the tiers would not slide or seal as well (because of the margin left for the siding ridges). I only had a few lengths of scape vinyl, just enough for the bottom tier sides, not the front, back or top. Although, I used different types for the port and starboard sides, they are the same color.





Yeah, I know the common street wisdom: ‘vinyl siding will not tolerate highway travel’. This may be true for the staple gun installation used on pre-fab homes, but I used a lot more care and the top partially covers the base in the travel configuration, so I was confident it would not be a problem.

I used half inch thick white foam with foil on both sides, and to my surprise, the unprotected interior side has held up quite well so far. I really like the vinyl, but it does have its down side: Like the original, I can quickly open and close the trailer without help, but the uneven siding does make it more prone to snags while lifting and complicates sealing the tiers.



After a couple of short trips we took it out on a very long one. With a total of 22 nights and 5 thousand highway miles and the vinyl siding has been totally stable.




The inside bed width is a bit over 57 inches. When folded the top is only about 3 feet above the frame deck but when opened we have great head room right where we need it (68 inches at the peak between the foot of the bed and door). But, comparing this to a typical fixed geometry (4 foot wall teardrop), it’s about a foot lower when folded yet has about 20 inches more headroom, so for us the extra work of a pop top is well justified.

I have become quite fond of using a tarp top (light, cheap and effective but watch out for tarp seams). I did not install the center sighting strip on the middle of the roof and I really missed it while backing into sites. Without it the tarp top did bow slightly at highway speeds, but it did not stretch the top and it was no problem at all.

I still hate “making the bed” from the end even if I can stand up during the process. Also, access to things stored under the very front of the bed is limited to when the bed is folded forward, so you have to be sure to put anything you might need during the night under the foot of the bed.

Now I need to decide what my new tow vehicle is going to be before I start a new trailer and relegate this one to utility hauling. I’m pretty sure I will be using as much vinyl as I can and that it will be some sort of pop top, but I will be a lot more careful selecting a frame.

[rebapuck]

Glad you have not been put off by the frame problems and still want to build.

[Junkboy999]

Great to see it back in action. Such a nice idea and cute looking trailer.

Cant wait to see how the next one turns out.