Tag Archives: making model cars

More stuff arrived, yay?

OK I got some more raw stock for the Mini Sprint-T yesterday. Basically I got 0.040″ thick styrene for making brackets and steering arms and the spindle backing plate where it connects to the axle. The amusing part is the minimum order was 4 sheets of which I will use maybe half a sheet if I’m profligate in my layouts, and when they packed it they included an extra 2 sheets to “protect” the actual material I paid for. So I needed less than ½ of a sheet, bought 4 and got 6, for a total of 12 times as much material as I need. The other funny part is unlike the rest of the raw stock I got this was sent in a padded envelope instead of a cardboard box stuffed with crumpled paper.

This sheet material is going to model structures that will be fabricated box structures on the real car like the engine and transmission mounts, or actual parts that are just that heavy because of the stresses involved and the critical nature of the part like steering arms. A major part of model building is “representation” rather than actually reproducing something in miniature. The exhaust system will be a good example of that for the Mini Sprint-T. The 1:1 version will have what is called a “tri-Y” or 4-2-1 exhaust system that improves torque below the torque peak but doesn’t change peak power much. It doesn’t get every last HP at peak though, so drag racers don’t use them much, but road racers, short-track oval racers, and autocross racers spend more time well below the torque peak and the tri-Y manifold is popular in those applications. Well this is a type of manifold that requires a large amount of fabrication for smooth flow, and ditto on the fabrication level for the scale version, and because of the difference in materials is actually easier to build full-scale than in miniature. Well to get around that I’m going to use the fact that the exhaust is going to be wrapped in insulating material to hide the fact that I’m just going to butt-join the rods representing the tubes of the manifold and not build the streamlined joints. The work would have been hidden by the wrap anyway and this saves a lot of work that will never be seen. The real tricky part will be the wrap, I’m still experimenting with stuff for that. My thoughts are whatever I use will require a paint wash to get the color right so it will have to be something that takes paint well. But that is something that comes much later in the build, so I have time to figure that one out. The current leader for that is hypoallergenic bandage tape, but I still need to do the paint test. And like I wrote, the actual wrapping will be in the future.

Line art of what I'm trying to make

Actual photograph of what I'm trying to make, kinda sorta.

But at any rate what I have now will fill in for complicated fabrications that would be a nightmare to produce in scale and not be discernible from cutting it from a single piece of heavy sheet. End of the current chapter. Next will be actually building the frame, which is like 80% of the build for this model. There are a few dimensions I’m not entirely positive about, some of which need to be hashed out during the model build because I can’t import the parts to my CAD program. The other ones are because I have to build to a rulebook that’s a bit vague about certain things like roll cages, and another rulebook that is more than a bit vague about the same things, and doesn’t mention anything about it except that for my car it’s required without any dimensions or tubing sizes. That is a really big help GoodGuys. “All Roadsters must have a roll cage.” That is verbatim everything printed in the rule book about roll cages. So what I’m doing is using the SCCA Solo rule book for roll bars and applying the rules to the rear hoop, and treating the car like it weighs 2500+ pounds, when I’m looking at maybe 1800 if I run iron heads on the SBC engine and something along the lines of a 4l60E transmission and the Ford 9″. Now if I get a quick change I can get the TH350 and take about 45 pounds off the car because I can change the gears to something really tall for the freeway and gas mileage without having to compromise to get the right gearing for racing. Just jack it up to unload the gears, pop the rear cover off, and swap the race spur set for the highway spur set and refill the rear end then go. And the car will be slightly quicker racing because the race gear doesn’t have to be compromised because of 9″ gear availability or having to get good highway mileage. But the other side of that is quick changes are much more expensive than the common 9″, and other junkyard rear axles are even cheaper and “close enough” on the gear ratio. But in the model I will be using the quick change, because I have 4 of them and no 9″ Ford in that scale. I have 2 of the V8 size housings and 2 of the 10″ ring gear size housings, but no 9″ Fords 😐. And you can see how decisions for the 1:1 car affect the 1:25 model.

And it’s getting late and I should be going to bed soon.

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Still thinking, this is not a drillllllllll

As the saying goes, fair warning. I am thinking about the Mini Sprint-T again. I realize this does not carry the same imminent danger to life and limb as its larger counterpart, unless you are the guy with the scalpel-sharp knife cutting plastic to bring the thoughts to fruition. Then fingers might be at renewed risk, but only mine. I did almost lose the end off one about 50 years ago while building a plastic model. But that is a tale for and from a different time.

One of the things I need to think about is stuff connecting the front and rear axle to the frame. In most kits this is usually molded as a single piece that gets glued to the frame and axle(s), but I have to build mine from raw stock and sometimes from hardware from a 3rd party like Ted’s Modeling Marketplace or Dirt Modeler . But mostly it is a matter of putting the axle in place and then figuring out where is a good place on the frame to tie in the locating links. And possibly adding more uprights and diagonals to the frame to prevent flexing IRL because we are trying to “model” something to make IRL. This is just “old school” 3D modeling, with actual physical pieces getting cut and built in actual physical space. And also because I like cutting material and gluing stuff together. So, indirectly thinking about the Mini Sprint-T is actually thinking about the full-size Sprint-T, just thinking in more achievable circumstances. I have the skills to make a presentable engineering model, but it might not be a display quality model. And what I really want is a display quality engineering model. But I will accept an ugly engineering model in lieu of a display quality engineering model if it means I have a representation of the Sprint-T in physical form.

Along those lines I bought new model-building tools as I can’t use the tools I did have because age has hampered my abilities and the new ones will fit my hands better (I hope). At any rate what I have now are jury-rigged from tools made for other things, or just flat out never intended to use for making models but can be forced into the role if you have the physical dexterity, which I don’t anymore. As an example there’s this one cut I need to make that requires rolling your wrist just right while holding the razor blade to get the desired curve, and my wrist no longer moves that way while imparting enough force to make the cut. When the tools get here I’m hoping I can make that cut. That’s the thing I’m dealing with because of my accumulated damages over the last 60 years. It’s not the tools, it’s the fact that I can’t make the tools do the thing any more. And this is why I’m sad/angry, sadgry? What is the word for that emotion. And Amazon was of no help in finding equivalent bits that I can spend my gift cards on…

And I just got a box the size of a shoebox containing a few plastic rods and sheets and lots of paper padding. Which was the first of the many packages I’m getting from the same order. I guess this is to prevent damage to the rods from bending as they can develop a permanent set if held in a flexed position. And now I need to find my butane torch and a can of fuel to use it so I can bend the rods without breaking them. This seems like a good place to stop writing and maybe start doing again.

Now what?

I have gone as far down the road my resources allow me to go towards the TGS2 and the Sprint-T. I could draw some pictures but that wouldn’t get anything built. And one of the things driving my depression is I don’t get anything done, I don’t get anything close to getting done, before I run out of resources, including the drive I need to see the end of the project.

So what can I do to get something done? I want what I’m building. I want it bad. I have wanted it for almost 50 years. But I just can’t muster the drive and the resources to get it. Is this related to my depression? Is there some part of my mind that is trying to destroy me and preventing me from working to make myself happy? Is it something that came from getting moved around so much as a kid? I know that part of the problem I have with making long-term relationships is a result of changing schools so much as a kid. I mean forget “Summer Romances” I was lucky to see people to the end of a semester, and between school years even if we didn’t get transferred most of the kids I was social with would get moved. So yeah, relationships were hard to impossible, because there just wasn’t time for any to develop.

So, what if I decided to complete something I had all the parts I needed to get to the final result? Something simple like build up one of the model kits into a complete car. I have two kits at hand, one that I robbed of parts to make stuff for the mini Sprint-T, and another completely untouched except for a parts inventory and then close the box. I could build up one of the kits’ 4 cars (between the 2 kits there are 4 complete cars) and have something I recently completed, to look at and inspire me. I’m going to start small and work my way up from there. I’m going to make something and complete the project if it kills me.

Lots of road course racing this weekend

There are two road courses today on the tube and one yesterday. And there was an Indycar race from a short (by Indycar standards) oval. And for those wondering we are way north (about 250 miles) of the hurricane down on the coast so all we have gotten was a few showers and some slightly damp kitties. I’m worried about my Houston friends as H is getting drowned with feet (not inches) of rain. Last report they are expecting 5 feet of rain total. I have some friends living less than ¼ mile from the Brazos river which is way out of its banks last report. I’m especially worried for them and their dogs.

I have been thinking about the Mini Sprint-T and the scale mockup for the TGS2 as they both need a body. What I have been thinking about is making a mold off of the AMT kit body then casting a plug from Bondo to use making a vacuformed body after making the desired body modifications to the plug. The plug would then be split in half to draw the body material over to a form with no undercuts so the body can be removed easily from the mold. The TGS2 mold would have the rear hatch molded separately so it can be hinged to work on the engine and I can test side versus top hinges for access to the rear suspension and engine.

Still thinking about making the little V6 run on E85 only. There is a hypereutectic piston I can use that is flat topped and can be zero-decked for the minimum clearance between the head and the piston, and then the heads will have to be angle-milled to shrink the combustion chamber in the head without taking too much material off the bottom of the head. And I realize that the preceding sentence read like technobabble to about 90% of my readers who were not brought up hard-core gearheads, but every word was a valid technical term or connecting word between. IOW it was all English, just not a common dialect of English. Translation: There is a cast piston made with a low expansion rate high-strength aluminum alloy that is flat across the top and can be fitted flush with the top of the cylinder. Then the heads will have to be milled on an angle with more taken off on the big side of the combustion chamber to get the chamber as small as required with the least amount of material removed. Hypereutectic pistons can support about 375 HP on gas for this engine, and I’m only hunting 225 to 250 HP with cooler-burning E85 so well within estimated stress limits, plus they are inexpensive especially compared to forged pistons. In this case that is especially true because forged pistons would have to be custom made, they aren’t available as regular production items.

The last sentence of the previous paragraph pretty much sums up my biggest frustration with this build, almost everything is $pecial order or cu$tom made, especially in the engine. Some of that is because there were no performance applications for this engine aside from the 1991 Shelby Can Am series which only made 150 engines putting out about 225 HP. The other reason is the last one left the production line in 2011, 6 years ago. Compare this to the ubiquitous SBC that was in production as a factory-installed engine from 1955-2001 and is still in production as a replacement engine for emission controlled vehicles of that era, and as a crate engine for new cars that are not required to meet emissions controls like the Sprint-T. There were literally tens of millions of SBC made in dozens of different sizes from 265 to 455 cubic inches when you include the hybrids made from mixing different blocks and cranks. One of those hybrids actually made production status as the Z28 302 in3, which was a hybrid of the 283 crank in a 327/350 block. One of the most popular hybrids is the 400 crank in a 350 block bored 4.030″ to produce 383 in3. How popular is it? There are now twice as many 400 cranks as there were 400 SBC engines made, the aftermarket is producing brand new cranks with the 3.750″ stroke of the 400 crank with the smaller main journals of the 350 block. It’s even easier to get parts for the LS/LT engine families than it is the 3.3/3.8l Mopar V6.

And that’s enough kvetching about the free engine I was given, at least stock replacement parts are cheap and easy to find because of the millions of them on the road. And some of those factory parts are suitable for use in a high-performance engine with a little preparation, like balancing or grinding off flash and light polishing to remove stress risers.

And I have to go now because my friends on the Gulf are finally starting to check in and I don’t want to miss any. Also my back is starting to hurt again. I did pretty well for several hours today but the pains are back.

Another day that didn’t go according to plan

Well today I was supposed to go pay for the return tickets from the eclipse viewing, and I even woke up early to do it. I was ready, but the check I deposited last week was not. For some reason it still hadn’t cleared. So I got out the money to get replacement ID and get my toes done went to the post office and got the money order for the ID and then got my toes done and walked home. I was a lot more comfortable walking out of the nail salon than walking in. I also picked up some bodywash on sale at the grocery store next door so I don’t have to wash with shampoo or smell bad.

Speaking of smelling bad, Clyde has been missing Mrs. the Poet something fierce. When I was shutting things down last night there was a bad smell in the bathroom where he was resting, so I blamed Clyde for using the bathroom as a litterbox as I took him to the front door. But when I got back to the bathroom the smell was gone. But the front door smelled like a litterbox until Clyde decided to move on to other things. My theory is he’s depressed because Mommy has been gone for so long and he was Mommy’s cat. When Mrs. the Poet is here Clyde spends most of his time on her lap being adored. And now he is going through withdrawal from Mommy Pettings. He did smell much better after being outdoors last night and most of the day. And now he’s curled up next to me a safe distance from my office chair listening to the TV show I have making noise while I write. That’s what he does with Mrs. the Poet except he sits in her lap. I move around too much for lap sitting when I’m working because I move forward to type and then back to proofread and think about it before I lean back forward to type some more.

Tonight I have the Velocity channel program Bitchin’ Rides running as inspiration, not so much for engineering ideas as for paint and trim and general design, and also for fabrication ideas. Also because I like watching people work metal, especially going from flat stock to a 3D part like a fender or a door skin. This program they scratched the entire floor for a ’52 Pontiac. But even when they aren’t making something even close to my car, it’s an inspiration for my car because they are making something. I want to be making something. That’s part of the reason why I’m making the small scale mockup of the TGS2, so that I’m building something.

And now I have to take care of the cats again before I go to bed.

It’s a good thing I checked in

I called the Lab Rat Keeper to verify my appointment and it was a good thing I did. Somehow my appointment was deleted from the book which was why I wasn’t called. Now instead of going to the Dr.’s office I will be paying bills and getting my toes done tomorrow.
You can see why I need my toes done
Ugly, ain’t it? That’s what happens when I let them go too long between getting them done, now I’m going to lose that one again. It happened back in the mid-1980s and it took most of a year for the new one to grow back, and it was terribly uncomfortable until it did.

So anyway I’m going to do tomorrow, or later today, what I was planning on doing Monday or Tuesday, but couldn’t because I was waiting for the Lab Rat Keeper’ office to confirm my appointment. I’m also still cutting floors for the scale mockup of the TGS2 with smaller rear wheel cutouts, but for some reason I haven’t been able to get the front ones square. And that plastic sheet from ADT is almost impossible to cut.

I woke up around 0500 what is now yesterday and I have been having problems all night long with falling asleep on my phone or at the keyboard, so I’m going to pop a sleep aid and try to grab some Zs.

I spent the weekend Doing Things so now I have something to write about

Saturday was grocery and laundry day, and Sunday was RPG day. Food was bought, and fun was had as we tried to save a slaughterhouse from the scourge of demon cattle, and cyber cockroaches, although I still haven’t wrapped my mind around how two such disparate things struck at the same time. The demon rats I can understand they’re just smaller versions of the demon cattle. But where did the cyber cockroaches come from? The demon rats were probably created at the same time as the demon cattle by drift from one group of animals to another, but the cockroaches had to have been a second attack against the slaughterhouse. We never did discover who was responsible for either attack because someone reported the demon cattle infestation to the Health Department.

I also watched the 9 Hours of Indy, formerly known as the Brickyard 400. It wasn’t supposed to take that long but stoppages for rain and for wrecks that completely blocked the track for several hours to clean up debris and spilled fluids caused it to be that long. I tuned in after the RPG group got finished, and still got to watch the last 40 laps. Congrats to Kasey Kahne on punching his ticket to the Playoffs.

Junk Mail has come through in spades in providing raw stock for the TGS2 scale mockup. ADT sent an actual sheet of plastic with their ad printed on it that will make an excellent floor and fender support. Also the local school district sent an ad on very heavy paper that can also be used for floors and diffusers, probably flexible enough to use for actual fenders as well.

Tomorrow I have to go deposit a check, and get my toes done so I can start walking again. I might be getting a visitor after lunch.

I’m melting, melting, what a world…

Heat indexes have been off the charts lately, from what I can tell. I haven’t been able to go for my walks so I have been spending most of the time indoors and hardly check the weather, but it’s 86°F in my office as I type this with the AC going. So it can’t be anything but hot outside. But just FYI my phone says it is currently 98°F outside. At 1855. So by deduction it must have been over 100 at some point today, say like between 1400 and 1500. ETA the 2200 news weather report had a 100° high temperature. And the urban heat island effect keeps the nighttime temperatures up, too. And this is where today’s headline came from YouTube

I’m not happy with the way the floor came out for two reasons. Number one is I forgot to include the front support for the front fenders, and 2) I made the rear cutouts too wide, as shown in the pictures. Seriously I left enough room for a 16″ wide tire and the widest race tire I have been looking at seriously was 14″ with the street tires in the 12″ range. And I have plenty of raw stock for the floor, finally. So the floor will get a do-over. And that’s why those 9″ wide tires in the pictures looked so lost in there. Even the 10″ wide tires for the Mini Sprint-T would have been swallowed up.

While I am on the subject of the TGS2 I have been looking at a pull-rod spring instead of direct mounted springs for 2 reasons. One reason is I can change the spring rate just by changing 2 bolts, either a little or a lot, The second reason is the unsprung part of the pull-rod is much less than the direct mount spring because the entire spring and shock are moving with the car. Yes they move with the axle but they are entirely supported by the frame so they are sprung weight. The bellcrank and mount add a couple of pounds but it is all sprung weight. But the primary reason to go with the pull-rod springing is adjustability, I can change spring rate and ride height in just a few seconds and swapping a different length pull-rod is much cheaper than swapping different shocks and springs. Literally a dollars to donuts comparison, I can buy or make a custom pull-rod for about the price of a dozen donuts where a spring and shock absorber are $200-300 assembled. With my budget this is a cost-benefit ratio I can most definitely live with.

And I need to take a shower and hit the hay.

This just ain’t my week

Yesterday was grocery day where I discovered all my money is in the wrong accounts and I didn’t have anything spendable at the grocery store. Fortunately my son was able to cover the <$20 tab so we could get out. I did manage to grab the last $0.50 pumpkin pie. I'm not pulling your leg, there was a 9" frozen pumpkin pie for 4 bits on my preferred shopper card.

Outside of the grocery store I’m having a shingles outbreak on my left arm, lots of itchy little blisters on my forearm. Also I’m dealing with an allergy attack that kept me awake all night when I couldn’t find the allergy/sleeping pills, so I’m on my 28th hour of semi-wakefulness. My biggest problem is itchy burning eyes, which is also my normal “Hey, Dummy, get some sleep” body response.

On the TGS2 mockup I’m still not happy with the way the layout of the cutouts for the front wheels has been going. The good thing is I just need to get the shape of this floor piece right and tack some wheels on it than tack the bucket on it and the cover on top of the body and it’s picture-taking time. Making the front fenders will be fun so you can see what I have been looking at in my mind’s eye. I’m still debating if I should completely enclose the back of the fender or leave it open for less drag. I don’t know which way will actually have less drag so I’m making both styles and doing A-B-A testing for gas mileage to determine lowest drag by seeing which one has the highest highway mileage. Lacking a wind tunnel or access to a long straight for top speed testing this is the best method I have to determine comparative drag.

I’m on my third car race of the day on the idiot box, Global Rallycross, which followed the 350 lap Indycar race from Iowa, which followed the Indy Lights race from Iowa. I was in bed trying to sleep during the Austrian F1 Gran Prix telecast. Of the 4 kinds of racing the Lights cars are closest in appearance to the TGS2 simply because of the expansive floor pan in front of the rear tires. Of the 4 kinds of racing my preference is the Indy Car, I mostly watch F1 for design inspiration, the Lights are the guys I will probably see in Indycar in future seasons, and the GRC are a bunch of guys getting dirty and sideways that looks like a lot of fun.

And I need to go to bed now before I faceplant into the keyboard again.

The fur kids are starting to miss Mrs. the Poet, Happy 4th of July

Clint and Clyde have noticed that Mrs. The Poet isn’t here to sit on, on the couch. Actually I think they noticed she isn’t here to wait on them hand and foot.

I’m running out of paper cardstock for the scale mockup because we have recycled so much of our junk mail there was only one small sheet left, so when I screwed up the front wheel cutouts for the floor there wasn’t enough left to do another one. And now I won’t get any of that kind of junk mail again for a long time, because I actually want some.

I could make mockup tires from 1″ dowels sliced and painted black. The IRL tires I’m looking at are all 25 to 26″ tall which is 1″ to 1.04″ in scale, and 7″ to 12″ wide which is 0.28″ to 0.48″ in scale. Doweling is cheap and easy to work with, so that might be the tire solution, cut them slightly wide and then sand them to the correct width.

I need to get my act together this morning and get to Harbor Freight for their 4th sale. Mrs. the Poet wants me to get a screwdriver set because I left mine where I was working out in the garage and people have been moving things around and just putting my stuff anywhere in spite of repeated admonitions to not move anything so I could find it again. But nobody pays me any attention when I ask to leave my stuff alone.

Anyway I need to do a lot of travelling locally today so I had better get a quick nap in before I have to go.