What is most challenging PWD project you have yet to start?

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ciodude
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What is most challenging PWD project you have yet to start?

Post by ciodude »

So what projects do you have on your drawing table that you just haven’t worked out the details yet to make? Using one of the big rig kits, I want to try to make both of these vehicles. I’m just not sure how to fashion the bodies yet.

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PeterT
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Re: What is most challenging PWD project you have yet to sta

Post by PeterT »

Wasn't that second vehicle from a made-for-tv movie Jan Michael Vincent post-apocalyptic sci fi thingy? SOOO cool when I first saw it, almost certainly intolerable today.

The second one would be pretty straightforward, unless you actually wanted the wheel triplets to spin like in the movie. Is this what you are after?
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ciodude
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Re: What is most challenging PWD project you have yet to sta

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PeterT wrote:Wasn't that second vehicle from a made-for-tv movie Jan Michael Vincent post-apocalyptic sci fi thingy? SOOO cool when I first saw it, almost certainly intolerable today.
Yes the movie was Damnation Alley with Jan-Michael Vincent and George Peppard. http://www.imdb.com/title/tt0075909/ I wouldn't try for spinning wheeles no (that's beyond me). I think my issue is I didn't want to have to glue together 4+ standard derby blocks to get the basic size and I don't have the right tools to rough cut my own pine block.

All suggestions welcomed.
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PeterT
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Re: What is most challenging PWD project you have yet to sta

Post by PeterT »

ohhhhhhhhhhhh.

Someone you know probably has a band saw, if not, might just be time to buy one! I don't think they are that expensive at the lower end. I have three friends who own them, so for my once a year needs I'm all set.

Since this would be (I assume) an outlaw car, you could just saw down a part of a 2x4, rather than building up from pineblocks. Just a thought. Going to burn up lots of wheels on that second one - even without the spinning business.

Best of luck (and please share photos if you undertake this!)
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Re: What is most challenging PWD project you have yet to sta

Post by Darin McGrew »

I'd build a hollow box out of basswood from the craft store. For big, bulky designs like that, I'm a big believer in designing the car to be hollow. To make the 5oz weight limit, the car is going to end up being hollow anyway, so you may as well design it that way from the beginning.
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Re: What is most challenging PWD project you have yet to sta

Post by FatSebastian »

ciodude wrote:So what projects do you have on your drawing table that you just haven’t worked out the details yet to make?
Darin's comment reminded me that I have always wanted to attempt a "racing block"; a body that looks just like the original raw block with 4 nails stuck in it (as it was assembled in two minutes), but in fact has been hollowed out with the CoM optimized.
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Re: What is most challenging PWD project you have yet to sta

Post by PeterT »

FatSebastian wrote:
ciodude wrote:So what projects do you have on your drawing table that you just haven’t worked out the details yet to make?
Darin's comment reminded me that I have always wanted to attempt a "racing block"; a body that looks just like the original raw block with 4 nails stuck in it (as it was assembled in two minutes), but in fact has been hollowed out with the CoM optimized.
Every year we talk about taking this exact approach but then don't do it out of, well, fear of poor performance. the aerodynamics would be awful of course, even with all else optimized.

I may try this next year for a non-racing car. hmmmm

would a block with a tighter grain be better than a looser one for this? And how to remove that much wood? forester bit for the bulk removal followed by a dremel for cleanup?
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Re: What is most challenging PWD project you have yet to sta

Post by drathbun »

A friend of mine was going to use the hollow racing block this year. I suggested that he cut it like a bandsaw box. I would not want to try to run a bit through the entire length of the box.

To make a bandsaw box the steps would run something like this:
  • Cut the ends off of the block, set aside and save them
  • Cut the remaining block in half along the long axis
  • For the two pieces you now have, hold them upright and cut the middle out. A picture would be better here, but ultimately when you're done you have two pieces of wood that look like a "U" shape. Further work could square out the corners.
  • Glue the two "U" shapes back together. With a very thin bandsaw blade the grain should match up fairly well. A block with a less dense grain would be best for this I think.
  • Glue the end pieces (cut off earlier and saved) back on the ends. The final result is a hollow box. Of course you would add weight to the inside of the box before gluing everything back together.
The worst part of this is carving out the "U" as it would require a taller bandsaw box, something with a clearance that would take the length of the block. If you didn't want to use a bandsaw here a forstner would work, or a router could be used. I think a bandsaw would remove it the fastest.
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Re: What is most challenging PWD project you have yet to sta

Post by rpcarpe »

Big Block Car - also considered it.
Would use 1 1/4" Forstner bit on the drill press. Adjust the drill depth to just shy of the 'roof'. Leaves just a bit on each side.
Keep the block nice & square, use extended wheelbase.

I did successfully drill a slanted hole through a block this year for my neighbor, lots of fun.
My wife started a new support group... Widows of the Pinewood Derby.
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Re: What is most challenging PWD project you have yet to sta

Post by 10range »

I have built a few cars that were hollow inside but shaped on the outside. This year I built a version of Lightning McQueen using the technique. I start off by doing all the shaping and getting the car to final form. Then I cut a thin slice off the top and bottom, cut out the interior with a scroll saw and glue the top and bottom back on. Using this technique my car this year ended up weighing 3.1 oz with wheels and axles.

A couple of years ago I built a car that was the shape of the block. In reality, it was a base frame from the original block with the rest of the car built from balsa wood in the same dimensions as the original block. I believe (have not had time to confirm or disprove this on track yet) that aerodynamics has almost nothing to do with speeds we are talking about. That year the block car that I built ran a fastest of 2.39 while the winning car in the race (which I also built) ran a fastest of 2.38. I suspect that one of the block cars wheels was damaged on the first run because after that it slowed dramatically to the 2.50 range for all remaining runs. I plan to test the theory this year following our Awana race.

The block car is worth building for no other reason than to confuse a bunch of people. On the first run it won the heat against two wedge shaped cars. Got some funny looks after that one 8)
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Re: What is most challenging PWD project you have yet to sta

Post by ciodude »

10range wrote:I believe (have not had time to confirm or disprove this on track yet) that aerodynamics has almost nothing to do with speeds we are talking about.
That is what I've always thought too.
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Re: What is most challenging PWD project you have yet to sta

Post by FatSebastian »

drathbun wrote:I suggested that he cut it like a bandsaw box.
Great idea! But given (what I think are) the suggested cuts, and understanding that the bandsaw blade removes a small amount of material between each cut, wouldn't there be gaps between the block pieces that might prevent it from all going back together perfectly?
10range wrote:I believe (have not had time to confirm or disprove this on track yet) that aerodynamics has almost nothing to do with speeds we are talking about.
ciodude wrote:That is what I've always thought too.
Those who have "had time to confirm or disprove" might disagree! Depending on the track, etc., this reference suggests that the difference between a block and a more streamlined shape may amount to a couple of inches (~1/3 car length) at the finish line.
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Re: What is most challenging PWD project you have yet to sta

Post by drathbun »

FatSebastian wrote:
drathbun wrote:I suggested that he cut it like a bandsaw box.
Great idea! But given (what I think are) the suggested cuts, and understanding that the bandsaw blade removes a small amount of material between each cut, wouldn't there be gaps between the block pieces that might prevent it from all going back together perfectly?
Yes, a bandsaw blade will remove some material depending on the width of the blade. It's a 16th or so I think. A block with a coarse (wide) grain would be best for this. An alternative to cutting the block in half and making two "U" shapes to glue back together would be to slice an 8th or so off of the bottom and then make one large "U" shape, the joint would then be lower towards the wheels and perhaps less noticeable that way. I had that thought after I posted earlier.
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Re: What is most challenging PWD project you have yet to sta

Post by FatSebastian »

Another contemplated PWD project seems so challenging that we will probably never get to it. The idea is to fabricate the various incarnations of the Thunderbold Grease-Slapper from the 17 episodes of Tom Slick, and then challenge the adults to identify what all these vehicles have in common. However, we may be approaching the end of parents having elementary-school-aged kids who might still recognize the George of the Jungle series. (If this theme is new to you, then FYI Tom fancifully converted the TGS to suit the wacky racing conditions and competitors of each episode, resulting in some rather unique vehicles.)

Anyone else up to the challenge? (Whoda, I'm looking in your direction... ;) ) This one would be the one of the more challenging designs to get down the track:

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Re: What is most challenging PWD project you have yet to sta

Post by whodathunkit »

FatSebastian wrote: Anyone else up to the challenge? (Whoda, I'm looking in your direction... ;) ) This one would be the one of the more challenging designs to get down the track:
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FS if the track would hold up i'd ride my unicycle down it!
This was one of the most challenging bikes that i ever learned to ride.
belive it or not i can still ride it.
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Don't know if i can drive one of those "wheelmens" or one wheel motorcycles
that are out there.

But you are right about this one wheel car being a challenging design FS.
And i'd like to see someone make one also, it would be neat to see one of these,
one wheel'ed wounders running down a pwd track.
As well as it would be a real challenge to make one.

You ever wounder what the finishing order was for 1968 Hannan/Barbera
cartoon series Wacky Racers was for the 34 episodes?
http://www.btinternet.com/~m.d.pratesi/ ... races.html" target="_blank
This site said there were 17 episodes and 34 races in all.
http://www.dan-dare.org/dan%20frd/wacky ... rivers.htm" target="_blank

One of the most challenging PWD project cars i'v yet to start building would be this car.
The car i've been looking to try and build here lately is the 1964 Indy 500 M/T
Mickey Thompson Sears Allstate Special car.
http://www.thompson-motorsports.com/indy64.html" target="_blank
http://www.davemacdonald.net/gallery/racing/indySD.htm" target="_blank

(And not because of the tragic loss of the driver Dave MacDonald.)

But because i really like this car design and shape and style of fenders it has on the car.
And because it looks alot alike to some of the pwd cars that are running with this fender style today.
What type of automobile can be spelled the same forwards & backwards?
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