AT Flip Pac Coming Along....

[calicamper]

I think the Aluminum build is a big step in the right direction. Fabbed aluminum carrys the same weight and strength properties to engineered cored composits. The old chopper gun glass built caps lacked that engineered strength and were heavy two negatives when it comes to this crowd. I wish them big sucess given its a much needed product given the large gap between toppers and campers in both price and weight.

 

[wanderer-rrorc]

View attachment 325238


black = cap
blue = lid
red = compressed gas spring
red+green = extended gas spring


at least that is how it looks like it would work to me

no need for an expensive and hard to obtain torsion bar
the force would be distributed on both sides of the lid (unless only one gas spring was used and who would do that) so no more torqueing displacement of the lid side to side
springs would be inexpensive and easy to install if/when needed.

I was going to build one a few years back but the canvas part would have been too hard to do.

Canvas isnt needed..1.9oz ripstop works well..machine stitchable and much lighter than canvas

 

[homemade]

Canvas isnt needed..1.9oz ripstop works well..machine stitchable and much lighter than canvas

You did great with yours. Since giving up on the thought of building my own I bought a flippac and am just not feeling it as far as a build. If my torsion bar ever goes I'll try something with gas springs and my flippac but it wouldn't likely be optimal, I have a crew cab so at least only the rear doors would be obstructed, or one door if I put one on one side only. I don't think I would want to try deploying the lid without an assist of some sort. My F350 is way off the ground even with a standard suspension so it would be more of an issue that with a small truck like a Tacoma. My son has a Ford Ranger which is miniature compared to the F350, I could see doing without assist with that type of truck.

What I really want to figure out are barn doors like a Gemtop instead of flip up glass in the back.

As an aside I think the flippac with a rain fly might be better than an improved tent without a fly, at least in wet weather. You can fold up a flip with a SLO fly keeping the flippac tent mostly or completely dry. without a fly you would be folding up a wet tent which seems like it would be much worse than an inferior tent like the flippac but kept dry with the fly.

 

[wanderer-rrorc]

You did great with yours. Since giving up on the thought of building my own I bought a flippac and am just not feeling it as far as a build. If my torsion bar ever goes I'll try something with gas springs and my flippac but it wouldn't likely be optimal, I have a crew cab so at least only the rear doors would be obstructed, or one door if I put one on one side only. I don't think I would want to try deploying the lid without an assist of some sort. My F350 is way off the ground even with a standard suspension so it would be more of an issue that with a small truck like a Tacoma. My son has a Ford Ranger which is miniature compared to the F350, I could see doing without assist with that type of truck.

What I really want to figure out are barn doors like a Gemtop instead of flip up glass in the back.

As an aside I think the flippac with a rain fly might be better than an improved tent without a fly, at least in wet weather. You can fold up a flip with a SLO fly keeping the flippac tent mostly or completely dry. without a fly you would be folding up a wet tent which seems like it would be much worse than an inferior tent like the flippac but kept dry with the fly.

thanks and mines not too heavy so I dont need an assist..but im a brute..lol!!

barn doors wouldnt be too hard google the leer caps..

when I fold mine up the inside stays dry. and I usually open it up on the next nice day and let it dry..but its 100% waterproof so it doesnt leak inside and opening it sheds the pools where the water collects.


I cannot be happier with my tent..some stitiching isnt so pretty..but as a first generation it looks really good..

my awning however leaves things to be desired...

 

[dman93]

@homemade thanks for the diagram. I have a FlipPac with torsion bar delete and just use brute force with long poles to flip it up and then catch on the descent ... easy with two people but sketchy with one person. I'm also an engineer, not a very clever one, who's put a lot of thought into alternative assist mechanism but I never thought about gas springs on the outside of the shell as you show. Since my truck is an XtraCab without opening rear doors I'm now curious if I could do this without blocking the "front" (only) doors. Obviously not as much leverage as if I could attach the struts to the lid further from the pivot point, but maybe this approach would provide enough force to slow the descent. Thanks!!

 

[homemade]

You can get some pretty high force gas springs that would probably be as powerful or more than the torsion bar. I have a couple 185# lift springs that are 20" closed and 36" extended (center of stud to center) that I might try if my torsion bar breaks. Maybe reinforce the inside of the lid edge at least on the passenger side, obviously the driver side can take the force as all of the torsion bar stress is focused on that side, and a backing plate for the attachment site on the cap. Stainless marine springs aren't even that expensive on Ebay but I have used the regular ones exposed to weather without an issue (I would go stainless though). If you know the weight of the lid (I don't) you could figure out how much force you would need to provide the lift you want at any distance along the lid edge from the hinge point so you can choose a spot that doesn't interfere with the doors. If you give it a try post up your results.

 

[dman93]

Thanks @homemade, I've actually designed some gas spring lifts in my career (30 years ago) so I can figure out the forces and geometry. It's been raining like crazy here so I haven't gone out to make any measurements yet. I think the lid weighs around 100 pounds with a portion of the tent included. I did look out the window at the truck on the steel and I think I can get adequate geometry and still open the cab doors. Thanks again for the inspiration to think out of the box and use external gas springs as you illustrated.

 

[homemade]

Thanks @homemade, I've actually designed some gas spring lifts in my career (30 years ago) so I can figure out the forces and geometry. It's been raining like crazy here so I haven't gone out to make any measurements yet. I think the lid weighs around 100 pounds with a portion of the tent included. I did look out the window at the truck on the steel and I think I can get adequate geometry and still open the cab doors. Thanks again for the inspiration to think out of the box and use external gas springs as you illustrated.

You're definitely the guy to be able to figure it out if anyone is. I'm no engineer so take anything I say with a giant grain of salt. If the strut is more vertical like the diagram I posted then you get more initial lift but the spring gets more in the way. more horizontal gives less initial lift but not as much, or not at all, in the way. My F350 has pretty small gas struts for the hood which I would guess is fairly heavy, they are fairly parallel with the hood and still provide good lift. That application also shows how durable struts are, 12 year old truck, brutal hot operating conditions under the hood and still seem to work the same as new.

If my torsion bar broke I think that at first I would try one strut on the passenger side so I could still use the crank on the driver side to assist instead of a long pole.

I hope you have success if you try it and post your results. I don't check this forum much but I'll keep an eye out, very interested.

 

[dman93]

If my torsion bar broke I think that at first I would try one strut on the passenger side so I could still use the crank on the driver side to assist instead of a long pole.

I hope you have success if you try it and post your results. I don't check this forum much but I'll keep an eye out, very interested.

Although the lid is "heavy" when you're first opening it (i.e. close to horizontal) the assist poles I use attach to the end of the lid so you have a lot of leverage. And closing the lid isn't too hard because the descent is damped by the tent ... just keep the tailgate closed and the trapped air makes a good damper. The tricky part for me is when the lid goes over center when you're opening it. The pole attachments are high up so you don't have much control and you essentially have to move yourself past the pivot point quickly so you're always able to push up on the poles, to keep the lid from falling too quickly into the open position. So I think you would need the most assist from the springs just after 90 degrees of opening, and then start relying on the damping to slow the descent. I am just starting to figure it out but I'm pretty sure I'll want to offset the lower spring mount from the lid pivot, not put it directly below as in your diagram. This may make closing a bit harder, but I think I can deal with that. If you use one spring and keep the crank (my crank was missing when I got the FP) you have to make sure the crank doesn't spin too fast as the shell pops over, which could be dangerous.

 

[homemade]

Although the lid is "heavy" when you're first opening it (i.e. close to horizontal) the assist poles I use attach to the end of the lid so you have a lot of leverage. And closing the lid isn't too hard because the descent is damped by the tent ... just keep the tailgate closed and the trapped air makes a good damper. The tricky part for me is when the lid goes over center when you're opening it. The pole attachments are high up so you don't have much control and you essentially have to move yourself past the pivot point quickly so you're always able to push up on the poles, to keep the lid from falling too quickly into the open position. So I think you would need the most assist from the springs just after 90 degrees of opening, and then start relying on the damping to slow the descent. I am just starting to figure it out but I'm pretty sure I'll want to offset the lower spring mount from the lid pivot, not put it directly below as in your diagram. This may make closing a bit harder, but I think I can deal with that. If you use one spring and keep the crank (my crank was missing when I got the FP) you have to make sure the crank doesn't spin too fast as the shell pops over, which could be dangerous.

:lurk:

 

[Arclight]

Although the lid is "heavy" when you're first opening it (i.e. close to horizontal) the assist poles I use attach to the end of the lid so you have a lot of leverage. And closing the lid isn't too hard because the descent is damped by the tent ... just keep the tailgate closed and the trapped air makes a good damper. The tricky part for me is when the lid goes over center when you're opening it. The pole attachments are high up so you don't have much control and you essentially have to move yourself past the pivot point quickly so you're always able to push up on the poles, to keep the lid from falling too quickly into the open position. So I think you would need the most assist from the springs just after 90 degrees of opening, and then start relying on the damping to slow the descent. I am just starting to figure it out but I'm pretty sure I'll want to offset the lower spring mount from the lid pivot, not put it directly below as in your diagram. This may make closing a bit harder, but I think I can deal with that. If you use one spring and keep the crank (my crank was missing when I got the FP) you have to make sure the crank doesn't spin too fast as the shell pops over, which could be dangerous.

What about a gear-reduction system to pop it up and down. As a bonus, it would be easy to make i hand-cranked or powered.

John

 

[MotoDave]

What about a gear-reduction system to pop it up and down. As a bonus, it would be easy to make i hand-cranked or powered.

John

I had a thought like this a while ago, using semi-truck air brake adjusters. SUPER robust, 20:1 gear ratio, and cost about $20 shipped brand new.
http://www.ebay.com/itm/HALDEX-AIR-...79-11662240-/301655749516?hash=item463c15738c

 

[dman93]

It's not clear to me if these air brake adjusters would work in both directions ... isn't their a ratchet of some kind? And other gear reduction boxes would require quite a bit of fabrication to attach given the limited space, and if using the existing FP spline attachment points, could only feed loads into one side. I think @homemade was onto something with the gas spring idea, and I'm working on it.

 

[wanderer-rrorc]

Although the lid is "heavy" when you're first opening it (i.e. close to horizontal) the assist poles I use attach to the end of the lid so you have a lot of leverage. And closing the lid isn't too hard because the descent is damped by the tent ... just keep the tailgate closed and the trapped air makes a good damper. The tricky part for me is when the lid goes over center when you're opening it. The pole attachments are high up so you don't have much control and you essentially have to move yourself past the pivot point quickly so you're always able to push up on the poles, to keep the lid from falling too quickly into the open position. So I think you would need the most assist from the springs just after 90 degrees of opening, and then start relying on the damping to slow the descent. I am just starting to figure it out but I'm pretty sure I'll want to offset the lower spring mount from the lid pivot, not put it directly below as in your diagram. This may make closing a bit harder, but I think I can deal with that. If you use one spring and keep the crank (my crank was missing when I got the FP) you have to make sure the crank doesn't spin too fast as the shell pops over, which could be dangerous.

I like the idea of the brake adjuster crank...


I have a 4ft extention pole I use to open and close mine..gives me more stability and even at the apex I still feel in control.

 

[upsidedown2]

That slack adjuster in the Ebay link will go both ways that is a pure manual adjuster. It is the automatic one that have a stop in them that you have to pull out or take it all the way out to back it off there is many types of auto slacks out there but that is manual. It takes a 9/16 end wrench and push the lock in to go both ways.