Layout plan.

TomLetsinger

2006 158" DIY toy hauler
Just a thought:
15 series 80/20 might be overkill. I used 10 series for all the cabinetry and 15 only for long spans supporting the bed.
I needed a slight bend in one piece of 10 series, it took two people (~350lbs) bouncing in the middle of a six foot span to bend it at all. It is very stiff stuff, particularly once you start bolting short bits together.
 

GeorgeRa

2013 Sprinter DIY 144WB, Portland OR
Just a thought:
15 series 80/20 might be overkill. I used 10 series for all the cabinetry and 15 only for long spans supporting the bed.
I needed a slight bend in one piece of 10 series, it took two people (~350lbs) bouncing in the middle of a six foot span to bend it at all. It is very stiff stuff, particularly once you start bolting short bits together.
Thank you for your input. I did some analysis with the 10 series frame and found it would be about 15lbs. lighter (18.9lbs versus 33.8lbs) than the 15 series. With 3 times higher weight of the module (the total module weight for the 15 series is 99lbs without wood panels) the deflection would be about 3.5 times higher with the 10 series than with the 15 series which could still be OK. The primary load on this galley module will be in the area of the floor mount during high deceleration so I could opt for the 15 series on the bottom of the module. I wouldn’t want the module flying towards my head during an accident. This is the heaviest module for all other modules I will likely use the 10 series.

George.
 

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Altered Sprinter

Happy Little Vegemite
That's neat reminds of the parabolic spring deflections as to tapers and cycling jounce til one day they break.
Cheers Richard
 
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Philj

New member
GeorgeRa,

Im not sure if I am interpreting what you are doing here correctly. In the beam analysis you have conducted you are using simply supported calcs, however in your cabinet the 36" dimensioned piece will be joined to the verticals so it is not simply supported as the joins at each end will support a moment. Also your previous diagram shows a vertical somewhere off centre so the beam will not be unsupported across its whole 36" length.

Could you expand on where you are intending on putting the 15 series to withstand the forces due to a crash and how you intend to secure the module to the van?
 

d_bertko

New member
I'll point out that essentially no construction is done in the real world with square beams.

The comparison should not be between 1.5x1.5 vs 1.0x1.0.

A better comparison is that the deflection on a 1x2 is less than a 1.5x1.5 even with an area of 2.0 vs the 2.25 of the larger series.

Of course the 80/20 comes in various profiles and an experienced engineer would use the higher-weight-per-foot profiles in critical use and the lighter profiles where the span is less.

Sometimes the extra width is useful to improve a door opening but narrower, deeper 80/20 would generally give you more interior volume and/or less weight for the same deflection.

It would be pretty funny to see a house where the floor joists were 8x8 instead of 2x12s!

Dan
 

GeorgeRa

2013 Sprinter DIY 144WB, Portland OR
GeorgeRa,

Im not sure if I am interpreting what you are doing here correctly. In the beam analysis you have conducted you are using simply supported calcs, however in your cabinet the 36" dimensioned piece will be joined to the verticals so it is not simply supported as the joins at each end will support a moment. Also your previous diagram shows a vertical somewhere off centre so the beam will not be unsupported across its whole 36" length.

Could you expand on where you are intending on putting the 15 series to withstand the forces due to a crash and how you intend to secure the module to the van?
Thank you for your interest. The stove, the sink and the countertop (~30lbs) will be supported by the upper portion of 4 vertical beams. The fridge (44lbs) will be mounted to 2 horizontal beams on the bottom, and 3 or 4 vertical beams. The frame weight will be somewhere in between 19lbs to 34lbs pending on series selection. The module will be attached to the front left seat mount (passenger van) somewhere not quite in the middle of its footprint. Heavy deceleration will cause forward twisting of the module and 2 rear module's corners will be pulling upwards. That is why I picked 2 36” bottom horizontal beams for this deflection exercise. The resulted deflections will represent the lift up of the rear bottom of the module.

The primary load will be on the bottom of the module and that is why I want to make the bottom assembly of 4 lower vertical beams with attached to it the seat mount gadget strong enough to survive a crash. The gadget is not yet on a paper but some concepts of quick connection are getting clearer.

The factory seat mount has 3 mounts per 3 passenger seat so one bottom mount should survive a crash with 300lb passenger weight.

I am not planning to do FEA or other more sophisticated method to design the galley frame; I will just go for a reasonable overkill.

My goal is to make all lower modules demountable allowing full transfer from converted to the passenger van. Removal of the module behind the galley module will allow remounting of the middle passenger seat making the van 2 + 3 + 2/3 (sofa bed) passenger van.

I hope this helped.

George.
 
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GeorgeRa

2013 Sprinter DIY 144WB, Portland OR
I'll point out that essentially no construction is done in the real world with square beams.

The comparison should not be between 1.5x1.5 vs 1.0x1.0.

A better comparison is that the deflection on a 1x2 is less than a 1.5x1.5 even with an area of 2.0 vs the 2.25 of the larger series.

Of course the 80/20 comes in various profiles and an experienced engineer would use the higher-weight-per-foot profiles in critical use and the lighter profiles where the span is less.

Sometimes the extra width is useful to improve a door opening but narrower, deeper 80/20 would generally give you more interior volume and/or less weight for the same deflection.

It would be pretty funny to see a house where the floor joists were 8x8 instead of 2x12s!

Dan
I agree that using the right profile for a load makes perfect sense. In case of 80/20 there is also an issue of assembleability which often relates to availability of slots in right places. For example 2012 (series 10) and 3075 (series 15) profiles have slots on one side only. All other none square profiles have slots everywhere which has impact on esthetics.

George.
 

Graphite Dave

Dave Orton
Just use the lightest 1 1/2" square 80/20. The only need for rectangular sections would be places where there would be a large unsupported load which might be the bed support. Using 1" on the overheads may make the panels more difficult to install so not worth the weight savings. More important than the weight of the 80/20 is the weight of the panels. I used 1/2" plywood panel thickness but next time would use some sort of sandwich panel with thin skins and rigid foam core. Advantage would be insulation and much lighter weight. I do like the wood finish on my panels but would that would have to go.

The most important thing in using 80/20 is to isolate the 80/20 from the Sprinter body with wood insulators.

This is not rocket science so no need to spend too much effort with calculations. You will find the stuff to be very rigid when it is installed. Just cut, make connectors, bolt it up and proceed to the next phase of the conversion.

I do have a question on having all the cabinets removable. Will you have quick disconnects on all the electrical and plumbing? It is going to be a lot of work to remove seats and install the cabinets and the reverse if you will need to change back and forth very often. If it is one change each year for a vacation then it is not a problem. Maybe only some of the cabinets should be removable instead of all of them? The best part of our conversion is to have everything we need to camp ready to go at all times. Add food,water and clothes and go.
 

GeorgeRa

2013 Sprinter DIY 144WB, Portland OR
Just use the lightest 1 1/2" square 80/20. The only need for rectangular sections would be places where there would be a large unsupported load which might be the bed support. Using 1" on the overheads may make the panels more difficult to install so not worth the weight savings.
I think that using one size would simplify assembly especially in interconnecting different series. I am planning to use 15-30 (1.5” X 3”) on bed support. Esthetically, I like 15 series smooth options which 10 series doesn’t have. I am not certain if I understand difficulties of installing panels in 1” series.

More important than the weight of the 80/20 is the weight of the panels. I used 1/2" plywood panel thickness but next time would use some sort of sandwich panel with thin skins and rigid foam core. Advantage would be insulation and much lighter weight. I do like the wood finish on my panels but would that would have to go.
I am thinking about using ¼” 7 ply bamboo plywood for most of panels, doors, and drawers; and 1/2" - ¾” bamboo plywood for cabinet’s tops. If I find lightweight laminate I would use it as well. All bamboo should look good. Bamboo is considerably lighter than regular plywood, about 13lbs / 4’ x 8’ x ¼” panel versus 25lbs for others.

The most important thing in using 80/20 is to isolate the 80/20 from the Sprinter body with wood insulators.
For overhead cabinets I am planning to use ¼” flat bar or angle fiberglass. I am not certain yet how to mount over the factory headliner so I need to get the Sprinter in my hands first.

This is not rocket science so no need to spend too much effort with calculations. You will find the stuff to be very rigid when it is installed. Just cut, make connectors, bolt it up and proceed to the next phase of the conversion.
I agree.

I do have a question on having all the cabinets removable. Will you have quick disconnects on all the electrical and plumbing? It is going to be a lot of work to remove seats and install the cabinets and the reverse if you will need to change back and forth very often. If it is one change each year for a vacation then it is not a problem. Maybe only some of the cabinets should be removable instead of all of them? The best part of our conversion is to have everything we need to camp ready to go at all times. Add food,water and clothes and go.
I am planning for 3 levels of conversion to passenger transformation:

1. Removal of the cargo module behind the galley module will allow me to replace the factory middle seat. There are no connections to this module. This can happen often.
2. Removal of galley, left rear and seat/bed modules will be more time consuming. All module I/Os will have quick connections. All lower modules will be mounted to various seat mounts or to each other. The left rear module will have the inverter, the AC/DC distribution panel and PV charge controller. Removal will be rather rare.
3. Upper modules will be rather permanent but removable. All monitoring and switchboard will be mounted on the overhead compartment behind the driver. Removal, perhaps never.

Under the van my plan is to mount:
Diesel water heater/furnace combo - Webasto
Batteries
Fresh water tank with the pump
Gray water tank.

George.
 

d_bertko

New member
Yes, George, you're right that the aesthetics are a major factor here. Most of us don't mind some overkill and tweaking things thinner or lighter is less important for our kind of prototyping. It's also less to think about if all the intersecting pieces are the same size.

I'm hoping that with all the useful 80/20 models and all the fabrication tips from our group can be distilled into my next build when this one wears out. Goal here is to see the best of the prototypes and then get some aluminum stock cut in a machine shop and TIG-welded.

But that requires bravery about finalization. Never something I'd do for the first one!

Dan
 

d_bertko

New member
It is true that 80/20 has similar pricing to MB parts and I suppose I should be loyal to the brand and not underpay for other solutions.

Keep up the good work prototyping versions 2.0, 3.0, 4.0.

When you guys engineer your 80/20 layouts to use 1/2 the metal with structural specs to fit the job drop me an email. Maybe I could afford it then:smirk:

---just kidding about the above

---I do think welded aluminum would be stronger than bolted.

Dan
 

GeorgeRa

2013 Sprinter DIY 144WB, Portland OR
Yes, George, you're right that the aesthetics are a major factor here. Most of us don't mind some overkill and tweaking things thinner or lighter is less important for our kind of prototyping. It's also less to think about if all the intersecting pieces are the same size.

I'm hoping that with all the useful 80/20 models and all the fabrication tips from our group can be distilled into my next build when this one wears out. Goal here is to see the best of the prototypes and then get some aluminum stock cut in a machine shop and TIG-welded.

But that requires bravery about finalization. Never something I'd do for the first one!

Dan
The volume to large degree will dictate manufacturing technology from sawed in situ plywood, adapting other structures, 80/20, welded stuff, stamped forms or $100K for plastic molding. In my volume of just 1 I am not brave enough to use welding on still to be proven designs.

New Westfallia represents to me high volume manufacturer but perhaps by over tooling they almost bellied up. Their extensive use of plastic molding from headliner down is great for high volume assembly and esthetics but very, very expensive. In my judgment Westfalias design and implementation is by far my favored one but to get to that level their engineering investment was huge.

I recently designed and built a custom gate with 1' tilt-up lower section but the design was simple and welding Al rectangular tubes was my best choice.

Even though I did not cut yet one piece of 80/20 I predict it will be easy to implement, change if necessary and it will look good; all in the volume of 1.

Mentioning Westfalia reminded me about their use of plastic bed innersprings used by Westfalia. I don’t think these springs are made in their mold but I found similar ones with 1 3/8” vertical travel. These springs with 4” foam could end up in my seat / bed.

http://www.westfalia-mobil.net/en/modelle/columbus/columbus-640f.php
http://www.froli.com/en/leisure/froli-bed-systems-mobil/froli-travel/
http://www.nickleatlantic.com/products1.html

George.
 

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Peter_C

New member
Curious why no one is looking outside of 80/20 to a more cost effective option? Coming from the solar industry where spans of 14' are common for aluminum extruded rails, there are 100's of options. Of course the cost is about 1/4, if not less, than 80/20 as it is a very competitive market.



My thoughts would be to buy simple aluminum rails of whatever size deemed necessary for the load, buy a welder capable of welding aluminum, and save money. I bought my TIG used for a reasonable sum, and although I am not the greatest TIG welder, I can make two pieces of metal stick together. A MIG with a spool gun is very easy to learn to weld aluminum with, and how a lot production welding is done. Aluminum does take a pretty powerful welder and more importantly a 200 amp main breaker, as they require a 100 amp breaker for themselves (Often a challenge on older houses as they only had 100 amp mains).

Cutting aluminum is super simple. Heck you can use most any power saw or even a hand saw. Just get the right blade. I have a 10" portable table saw that I put a 7 1/4" metal blade onto for ripping fairly thick aluminum. I haven't had a need yet, but could easily change out the saw blade on my 12" compound miter saw to a non ferrous metal blade aka aluminum blade (I have a 14" metal cold cut saw and a horizontal band saw for metal).

Doing a build like most in this thread have done, or plan to do, requires a fairly extensive set of tools both hand and wood/metal working with some specialty stuff thrown in IE: Rivenut tool. I look at it if you can break even and come out owning the tool doing it yourself then take the DIY approach. My hat will always be tipped to anyone doing DIY stuff :thumbup:

Not dissing those that used 80/20 as it has tons of benefits, and looks beautiful. It is the cost that kills me. I have learned a lot reading these threads and will continue to be schooled :professor: until someday I can take on my own project...
 

Graphite Dave

Dave Orton
What are some of the options that we should be considering? Brand names? Sources? 80/20 is sort of a generic name for using extrusions. There are other manufacturers of similar extrusions. Is there a manufacturer out there that has a less expensive product line that functions similar to 80/20?
 

TomLetsinger

2006 158" DIY toy hauler
80/20 is the copyrighted name for the products of 80/20, Inc.
The generic term for this type of material is T-Slot framing. There are other sources for T-Slot framing. Shouldn't be hard to find.
I found that the way to keep the costs down on 80/20 is to do the cutting and drilling yourself. Just buy the longest pieces of extrusion that can be shipped to you. Also consider the connectors, 80/20 has many types, some require complicated machining while others need just a well placed hole. Some are quite expensive, some aren't. Also there are less expensive sources for general hardware, just make sure you get the right thread and head shape for the connectors you are using.
 

Graphite Dave

Dave Orton
I used T-slots from Futura Industries(www.tslots.com) for two reasons. At the time 80/20 did not have the smooth face extrusions without the surface lines. Smooth looks better to me. The second reason was the T-slots brand was available at a distributor within driving distance so I did not have to pay truck shipping. Bought 20' lengths and had distributor cut them into 8' and 12' length to fit inside the van. The T-slots are interchangeable with 80/20. The T-slot catalog does not have as many choices available compared to 80/20. Make your own connectors for least cost and 15 minute delivery. No need to do any complicated machining for our purpose. Go to local fastener distributor for fasteners.
 

d_bertko

New member
I like Peter's idea of buying tools with the money you save on more common materials.

The 80/20 projects I priced came to about $1500. If I used aluminum box beams instead the cost of materials would run about $500.

I did take an evening welding course at the local voke-ed high school. The wirefeed was easy, the fancier tig stuff required more skills. But even the first amateur hour things I made were awesomely strong compared to anything I ever bolted together.

Likely will sign up for the winter term "projects" course if I can get in.

Admiral Metals is in a near suburb and they will happily cut metal extrusions down to whatever fits inside or on the Sprinter roof rack. Nice to hold stuff in your hand first!

I think 80/20 and other T-extrusion places do sell some expensive but clever hardware that can be added to the much cheaper box beams I'd likely use as building blocks.

http://www.admiralmetals.com/AdmiralMetals/?page_id=31
 

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