Of the 3 bodies styles shown which is the weakest?

[5KidsRacing]

The first body style is the ladder style:

The second is the Reversed Ladder:

The third is the X Factor:

All (3) bodies are the same weight (give or take very little)... All have the same wheelbase and are made completely of the same material (no different material ribs) . Rears of all of the bodies are solid and rigid like they have been filled with weight.

If you held the rear axle firm and pushed up with a force at the DFW which body would be the weakest and twist (deflect) the most?

I will post my results later in the week.

 

[E.T.Racing]

I would say it would be the reversed ladder.

 

[bracketracer]

I vote for the reversed ladder also, but I think the ladder style won't be far behind if tested as shown.

Are you going to try a monocoque design also?

Something I'm curious about, though. Does torsional stiffness play a large role in pinewood speed? With the track being "flat" do the bodies twist much during the run? Or do you look for a design that dampens the vibration to cancel the "milliscrubs of speed"?

Just one more thing I scratch my head over. With the NDFW cantilevered out, do the vibrations of it, out there in space, slow the car?

 

[ZZ Racing]

reversed weakest, x-factor strongest.....

 

[5KidsRacing]

Bracketracer..... No, sure, depends, yes.........and yes I think so....

With regards to car bodies I think drilling the body correctly is the most important. How you get that done, when you do it and what happens after you did it is very important. Some guys use the above styles to reduce the body weight and add tungsten horsepower, but some don't remove any additional wood at all.

I just thought it would be fun to see which of the above designs, from an Engineering standpoint, were the strongest/weakest.

 

[pony express]

The X body looks strongest. My bodies typically weigh .45 oz after drill and adding the friction plates. That's heavy compared to some of the other bodies I've seen. The most important thing in drilling the body is the solid front axle of the body. Leaving enough wood up front to keep it solid takes the place of torsion bars.

 

[Guest]

The first body style is the ladder style:

The second is the Reversed Ladder:

The third is the X Factor:

All (3) bodies are the same weight (give or take very little)... All have the same wheelbase and are made completely of the same material (no different material ribs) . Rears of all of the bodies are solid and rigid like they have been filled with weight.

If you held the rear axle firm and pushed up with a force at the DFW which body would be the weakest and twist (deflect) the most?

I will post my results later in the week.

Are all the ribs the same thickness?...........the "X" frame has radius's in all corners, the first two are square in the corners. Hmmmmmmmmmmmmmmm?????????????????????????????????

 

[5KidsRacing]

Even if I added radius's in every corner of every body type it wouldn't change the end results of this poll.

 

[Guest]

Even if I added radius's in every corner of every body type it wouldn't change the end results of this poll.

Ahhhhhh do it anyway, looks nicer!!!

 

[ZZ Racing]

I have tried all three styles and I know which one works the best for me. I'm still running two of the three with one being a national championship car so you can't argue with success.

 

[Quicktimederby]

My guess is top to bottom, top being weakest bottom being strongest. I think in terms of speed the one that can deflect the most vibration would be the fastest, if all other things were equal. Just my though on the matter.

 

[OPARENNEN]

If you covered all three with Monokote (top and bottom), AND transferred the same wheels and axles (i.e. equal prepping) from one car to the other, and assuming the weight pattern in each was the same,

I predict that all three would be equal equal within a margin of error.

 

[txchemist]

I'll go out on a limb ( of pine) and go in this order

Weakest, #2 reversed ladder
Next , #3 the x
strongest resistance to torque is #1 the ladder

 

[B-4 Racing]

One, two, three. Top weakest, second stronger and bottom strongest. My gut.

 

[Guest]

Even if I added radius's in every corner of every body type it wouldn't change the end results of this poll.

Ahhhhhh do it anyway, looks nicer!!!

I hope ya know I was just bustin on you Scott. I think the weakest is the ladder #1......the ribbed one is the 2nd strongest and the X factor I think would be the strongest. In my mind the X factor covers all the bases. The reversed ladder one is a very close 2nd and easy to make. The X factor is do-able, but much more difficult to make. #1 the ladder one............nah, don't think so!

I think the ladder style takes care of a load from side to side. The reversed ladder is very ridgid front to back where there is a load at the transition and is pretty good as well from side to side. The X factor I think is the best as it takes car of loads coming from North, South, East and West. It is triangulated and any time you triangulate a structure it makes is super strong.

You have to remember..........the question was, "which frame is the weakest?" Not which frame works the best!

 

[Hogans Racing]

I run the X factor and the ladder style, never tried the reverse ladder but INMHO the X factor is much stronger than the ladder style. So I would say X factor strongest, ladder style, than reverse ladder weakest.

 

[Rocket car]

I run the X factor and the ladder style, never tried the reverse ladder but INMHO the X factor is much stronger than the ladder style. So I would say X factor strongest, ladder style, than reverse ladder weakest.

Ditto!

 

[GravityX]

OK, I just read the post and viewed the pics. I decided before reading any other posts to post my own thoughts prior to getting swayed by other ideas. The weakest will be the ladder followed by the reverse ladder and finally the X-Factor.

The ladder has no cross-sectional strength, if the diagram truly represents the actual piece, too much open space between rungs. Twist is inevitable in this body style.

The Reverse-Ladder body is stronger than the former due to the narrow spacing between the rungs and may be harder to twist. More material collectively to twist and may just edge out the X-Factor body style.

But I feel the X-Factor body style provides greater strength due to the cross-sectional bracing, where any load placed upon the DFW will may be directly transferred to the opposite rear wheel, if anything where to occur. My thinking tells me very minimal twist will happen here.

Another thought, I would totally remove any material forward of the cross-sectional brace (triangle area) on the NDFW side. I don't believe strength is needed here as the wheel is not touching anything. I would fill this area with some light weight foam filler to absorb any vibration, further lightening the body.

A lot of thoughts and ideas running through my head about this but this is what is sitting on top right now. Maybe more to come...

OK, now that I have posted I will read the other posts. If I decide to make any changes or thoughts to this post I will make an edit and changes will be in RED. Just in case a bulb goes off.

This is truly one of the reasons I continue to read this forum on a daily basis, you just never know what subject we are going to cover. This is turning out to be an excellent thread. Certainly looking forward to hearing your findings and final thoughts on this 5Kids, from your engineering perspective.

 

[GravityX]

I think this is a question for JB07 with the angled NDFW wheel placement. I think there is something to be said about his design, more there than meets the eye.

Just one more thing I scratch my head over. With the NDFW cantilevered out, do the vibrations of it, out there in space, slow the car?

 

[Papa V Racing]

Just asking since I am a plane & rocket guy..

How much torque is really on these cars running down the track. I would say at the slope would be the area they would get any force that might twist a body...

We make planking the body with balsa wood and super glue a topic as this creates one super strong bond and creates a one piece body and solid ride...

Now taking the X body using monokote if done incorrectly can warp a body... It shrinks as the contact adhesive adheres and if pulled to tight can cause issues...

So this is just one thought as some of the fastest guys put all theories to bed....

I'm still learning a ton .. But the force these cars go through and what I put my planes through are no where close to comparison the G's on a high performance plane flying 80-120 mph throwing it into a bank verses a car hitting the slope

..

I'm just not seeing the force these cars go through .. Just me and my in experience though..

Papa V