 Cart Done TOPIC CHANGE - Is my shell twisted?, New pics within. |
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| snflupigus |
 Nov 9 2006, 12:47 AM
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#1
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Member  Group: Members Posts: 320 Joined: 29-May 05 From: Gilbert, AZ Member No.: 4,163 Region Association: None  |
So I designed this cart for the body while I continue my so-far year long body prep for rust repair and restoration... all suspension is still attached. My design is 24 inches high. My jackstands lift the car to 17 inches. I needed 7 more inches - what was i thinking! it was VERY scary lifting the car and jack stands at each corner with 2x4 jack stand supports and jack pad/height "enhancer" LOL
Here it is. I'll get pics of the car up on it later. (IMG:http://www.snflupigus.com/pics/carcart2.jpg) I'm pretty sure it is MORE than strong enough to hold the car up. The castors I bought however may not be good enough as it is VERY difficult to move the car. They are each rated at 300 lbs. I guess it weighs more than 1200 with the suspension still on? Can somebody take my autocad file and do an computer structural analysis on it? ACAD FILE |
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| messix |
Nov 9 2006, 01:11 AM
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#2
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AKA "CLUTCH KILLER"! Group: Members Posts: 6,995 Joined: 14-April 05 From: between shit kickers and pinky lifters/ puget sound wa.north of Seattle south of Canada Member No.: 3,931 Region Association: Pacific Northwest |
your casters are also carrying the weight of the dolly/cart.
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| Aaron Cox |
Nov 9 2006, 10:35 AM
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#3
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
300 x 4 casters = 1200lbs....
car weighs about 2000.... + cart |
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| URY914 |
Nov 9 2006, 10:47 AM
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#4
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I built the lightest 914 in the history of mankind. Group: Members Posts: 120,578 Joined: 3-February 03 From: Jacksonville, FL Member No.: 222 Region Association: None |
I like it but I would go with 4 x 4's for the bottom members. Those 2x 4's on thier side are weak. All the weight is being carried by them. Good use of diagonals.
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| jsteele22 |
Nov 9 2006, 01:03 PM
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#5
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Senior Member Group: Members Posts: 727 Joined: 24-August 05 From: Colorado Springs, CO Member No.: 4,653 |
As for the castors, they seem a little under-sized, but if you don't plan on rolling the car around much they may be fine. A failure of the cators would probably not be a ctastrophe, just a PITA. But it wouldn't hurt to upgrade em just to be safe. As for the structure, I would worry a little bit about all the points where the 2x4s join. Not much "meat" there to start with, and a screw/nail near the end of a 2x4 can weaken it significantly - especially if the wood is old or dry. Don't forget, you're looking at forces on each joint that are much, much greater than on house framing. I agree that I'd probabl;y use 4x4s at least for the bottom square. Another thing that would strengthen the design a whole lot would be a skin of plywood screwed onto the 4 vertical surfaces. This "stress skin" design gives a lot of protection against distortion, as do the diagonals, but it also helps hold the two pieces on either side of a joint tightly together. The plywood doesn't need to be all that thick to provide a lot of strength. |
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| URY914 |
Nov 9 2006, 01:13 PM
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#6
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I built the lightest 914 in the history of mankind. Group: Members Posts: 120,578 Joined: 3-February 03 From: Jacksonville, FL Member No.: 222 Region Association: None |
I agree, plywood=good. (IMG:style_emoticons/default/biggrin.gif)
Even 1/4" screwed on the outside every 3" would really tie it all together. |
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| GWN7 |
Nov 9 2006, 05:04 PM
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#7
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King of Road Trips Group: Members Posts: 6,280 Joined: 31-December 02 From: Winnipeg, MB, Canada Member No.: 56 Region Association: Northstar Region |
QUOTE(URY914 @ Nov 9 2006, 11:13 AM)  I agree, plywood=good. (IMG:style_emoticons/default/biggrin.gif) Even 1/4" screwed on the outside every 3" would really tie it all together. Add some wood glue to the plywood/screws idea.......extra strong As said, 4' X 4" on the 2 ends that hold the weight....... Car without motor/trans about 1600 lbs |
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| McMark |
Nov 9 2006, 06:49 PM
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#8
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
(IMG:style_emoticons/default/thisthreadisworthlesswithoutpics.gif)
Since nobody else posted it.. (IMG:style_emoticons/default/tongue.gif) |
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| snflupigus |
Nov 9 2006, 07:55 PM
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#9
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Member Group: Members Posts: 320 Joined: 29-May 05 From: Gilbert, AZ Member No.: 4,163 Region Association: None |
(IMG:http://www.snflupigus.com/pics/cart1.jpg)
(IMG:http://www.snflupigus.com/pics/cart2.jpg) Is it safe to crawl under after i get the suspension off? Who has procedures for the front? I assume i should release tension on the torsion bars first (IMG:style_emoticons/default/smile.gif) what order of removal is suggested. Thanks. also, are they 22mm rear nuts on the trailing arms? I need to go by the larger metric set. I only have up to 19mm When planning I decided that I didnt need 4x4s at the bottom beause they were essentially just tying the legs together. Laid down they are only under compression weight from the 2 "t'd" 2x4s that are 17.5" vertical under compression down to the wheel. I also modified the diagonals for the small insides so i didnt have to calculate angled cuts on the 2x4s. I only have a hand held 19.2v circular saw not a table saw which would have made that all a bit easier and faster. i just turned em and cut em to length to wedge in instead. probably sacrificed a bit of strength but it is very stable and doesnt rock or sway at all when i jiggle it with the car on it. My only worry is that the car does not sit flat on the cart, the front doesnt rest on the donuts but on the center tunnel, so i think i should shim that? And it almost seems like the body is twisted along its front to rear axis by about a 1/2 inch. when i put it up on the jackstands, it would rock from drivers front to passenger rear... well, i just remembered that the rear donut seems bent into the long a bit. maybe thats it. i also think i bent the long in a tiny bit lifting using a 2x4 flat to spread the weight but just inside the donut at rear. I'm not going to worry about it all too much... tell me if maybe i should. I didnt want to put plywood on the outside due to restricting me access to clean the underbody then. |
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| G e o r g e |
Nov 9 2006, 08:08 PM
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#10
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Dr Group: Members Posts: 1,905 Joined: 20-September 05 From: Southern Cal Member No.: 4,832 Region Association: None 
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what is the color on those rockers L96 b?
some one cut of the tops of your front qtrs (IMG:style_emoticons/default/biggrin.gif) |
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| cantley914 |
Nov 9 2006, 08:13 PM
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#11
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Pipeline surgeon Group: Members Posts: 306 Joined: 15-June 04 From: Cantley, Qc Canada Member No.: 2,210 |
Like the others said, the casters are a little undersized.
As for the support, NICE carpentry job !!!. No problems for the safety factor. I would`nt be afraid to crawl under. Steph |
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| Aaron Cox |
Nov 9 2006, 08:14 PM
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#12
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
it looks like the 2x4's are bowing... (bottom sides..)
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| Chris Pincetich |
Nov 9 2006, 08:15 PM
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#13
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B-) Group: Members Posts: 2,082 Joined: 3-October 05 From: Point Reyes Station, CA Member No.: 4,907 Region Association: Northern California |
That looks like a cool idea for winter work in the garage (IMG:style_emoticons/default/beerchug.gif)
Is it safe? Plan for the worst. You are under the car and have a 4 foot breaker bar turning 300 lb torque and the front caster rolls into the crack then breaks off, will the structure fold and collapse? The cross bracing needs to be strong, and yours looks minimal for side to side flex. Through bolts, nails, screws, or glue or all? (IMG:style_emoticons/default/biggrin.gif) If you *search* threads started by SirAndy, you will find pics of a seriously twisted teener. His had lots of fiberglass body panels too. |
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| snflupigus |
Nov 11 2006, 02:53 AM
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#14
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Member Group: Members Posts: 320 Joined: 29-May 05 From: Gilbert, AZ Member No.: 4,163 Region Association: None |
QUOTE(George H. @ Nov 9 2006, 07:08 PM) what is the color on those rockers L96 b? some one cut of the tops of your front qtrs (IMG:style_emoticons/default/biggrin.gif) Hehe, ya, all the quarters are a bit shorter than stock. shalom. (IMG:style_emoticons/default/smile.gif) chalon. whateva! Not sure on the color, a very pretty color though where its not painted over and still fresh. I think it wasnt a really really popular color though because a porsche purist really frowned when he saw it under the white... i made sure to let him know the PO did all the mods. (IMG:style_emoticons/default/smile.gif) QUOTE(Aaron Cox @ Nov 9 2006, 07:14 PM) it looks like the 2x4's are bowing... (bottom sides..) Nope, not bowing at all. Some of the 2x4s are warped and I had to pull them into straight as much as i could. I had some difficulties with some. QUOTE(ChrisNPDrider @ Nov 9 2006, 07:15 PM) That looks like a cool idea for winter work in the garage (IMG:style_emoticons/default/beerchug.gif) Is it safe? Plan for the worst. You are under the car and have a 4 foot breaker bar turning 300 lb torque and the front caster rolls into the crack then breaks off, will the structure fold and collapse? The cross bracing needs to be strong, and yours looks minimal for side to side flex. Through bolts, nails, screws, or glue or all? (IMG:style_emoticons/default/biggrin.gif) If you *search* threads started by SirAndy, you will find pics of a seriously twisted teener. His had lots of fiberglass body panels too. Well... it ACTUALLY ROLLS now... with all suspension off of it it is fine now. not like its on ice sliding or anything but it is easy enough to move and goes over the garage cracks ok. I just used 2 1/2 inch screws all around, most joints have multiple from different angles and sides of the wood. It is very sturdy now even moving. before with all the suspension on it, it was actually still solid and didnt wobble at all. but by knocking on each leg i could hear the pressure bearing down. tight with no resonance vs the other cross bracing which still resonated like a regular 2x4. If i were to build it over again. I would use larger castors, make it a bit shorter and take the time to use wood glue and be a bit more precise with my cuts. I would have done my cross bracing just like the design too vs the improv'd way i ended up doing it. here are some more pics. I'll put together later full out dimensions and supply list for future builders too. NOTICE the passenger is off the wood by an inch or so... not sure if this is because my cart is crooked, my garage floor is crooked or the body is crooked. OR if its just because the center tunnel of the car is resting on the 2x4 cross brace in the front instead of on the donuts. (IMG:http://www.snflupigus.com/pics/cart3.jpg) (IMG:http://www.snflupigus.com/pics/cart4.jpg) (IMG:http://www.snflupigus.com/pics/cart5.jpg) (IMG:http://www.snflupigus.com/pics/cart6.jpg) (IMG:http://www.snflupigus.com/pics/cart7.jpg) |
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| snflupigus |
Nov 11 2006, 12:52 PM
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#15
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Member Group: Members Posts: 320 Joined: 29-May 05 From: Gilbert, AZ Member No.: 4,163 Region Association: None |
bump for thread topic change...
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| jasons |
Nov 11 2006, 01:17 PM
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#16
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Jackstand Extraordinaire Group: Members Posts: 2,002 Joined: 19-August 04 From: Scottsdale, AZ Member No.: 2,573 Region Association: None |
Are you sure your cart is square? Theres a good chance those casters are going to fold under that weight.
Also, next time you need help, put out a request. I would have helped you lift that thing. I'm sure we could have got enough local guys to do it. (IMG:style_emoticons/default/smile.gif) |
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| SirAndy |
Nov 11 2006, 01:49 PM
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#17
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Resident German Group: Admin Posts: 41,636 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
QUOTE(snflupigus @ Nov 11 2006, 12:53 AM) NOTICE the passenger is off the wood by an inch or so... yupp, looks tweaked ... did you install the body kit? if not, one of the most common reasons people install a FG body kit is that they have insurance money to spent after the car was hit in an accident ... ask me how i know ... (IMG:style_emoticons/default/icon8.gif) good news, nothing a celette can't fix. bad news, that won't be cheap ... (IMG:style_emoticons/default/smash.gif) Andy |
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| TravisNeff |
Nov 11 2006, 02:31 PM
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#18
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914 Guru Group: Members Posts: 5,082 Joined: 20-March 03 From: Mesa, AZ Member No.: 447 Region Association: Southwest Region
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Looks like the floorpan is buckled up wher that donut is, maybe from the car being jacked up by the floorpan instead fo the donut. The tub look a little tweaked too. I would check to see if the cart is square/level.
Oh and the corner that is off the cart may not be the corner that is bent, could be the opposing rear corner as well. |
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| nebreitling |
Nov 11 2006, 02:36 PM
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#19
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Member Emeritus Group: Members Posts: 3,314 Joined: 26-March 03 From: San Francisco Member No.: 478 |
does look a little 'off'. how does it compare in measurements?
http://www.914world.com/specs/bodydims.php?...5e8c2a26a20e538 http://www.914world.com/specs/underdims.php...5e8c2a26a20e538 btw, i would have really built that cart out of rectangular steel tubing... |
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| MartyYeoman |
Nov 11 2006, 03:05 PM
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#20
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Senior Member Group: Members Posts: 1,518 Joined: 19-June 03 From: San Ramon, CA Member No.: 839 Region Association: Northern California
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QUOTE(snflupigus @ Nov 8 2006, 10:47 PM) Material: Douglas Fir Modulus of Elasticity: 1950ksi Tensile strength (ultimate): 340psi 500lb loads at each top corner on 3.0in dia area (102psi) Area moveable support at each bottom corner over caster mount plate area. It looks like you're barely stressing the thing. Attached thumbnail(s) 
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