You'll never believe how much difference 3/4 of 1% will make on a grade. You remember Lil Huffy, who got his name huffing and puffing one car up a straight 3% grade?
Well, this is Lil Huffy on a 16" turn on a 2.25% grade.
If you counted the cars he was pulling and came up with six, it's because you missed the black tank car in front of the orange tank car.
Lil Huffy pulled all 7 cars up to the top, rang the bell, and rolled back down here to pose for this picture.
My accomplishments pale in comparison. I layed the first 18 feet of track on the grade and fine tuned it a little. That will get me out of the tunnel on the grade.
All that leaves before I can put on the second level is staging.
Speaking of staging, I got the roadbed installed. Unfortunately, I'll run out of Fast Ties for my Fast Tracks turnouts before I can finish. I'll also run out of ground throws.
I have an idea for the ties. Ground throws will take money.
On the flip side, the layout got a thorough sweeping out. That's not all that glamourous, but I feel a lot better.
Chip
Building the Rock Ridge Railroad with the slowest construction crew west of the Pecos.
I bet it is like Lil Huffy saying thanks for making the grade easier.
David
To the world you are someone. To someone you are the world
I cannot afford the luxury of a negative thought
This is where I have to call out the various formulas for grade compensation in a curve. According to one more relaxed version, the equivalent grade on that 16" radius curve would be well over 4%. Granted there is more friction for the loco drivers as well, but if that loco can't pull 1 car up a 3% grade, no way is it going to pull 9 up a 2.25% curve on a 16" radius curve if these compensation formulas are actually valid.
I've always felt the exaggerated the effect of curves, but with no grades on my last two layouts, I had no way to test it. Here is some empirical evidence that curves as sharp as 16" radius do not nearly double the effective grade as the formulas would have you believe - One puts actual grade = grade + (28/radius), which makes the 2.25% actual grade into 4%, and the ogirinal formula is actual grade = grade + (32/radius) which would put the effective grade at 4.25%! Not a chance this loco could pull 9 cars up that if it can't pull 1 on a 3% tangent.
Does the curve have an effect? It has to, especially below a certain radius when the taper of the wheels can't compensate. But I don't think it's nearly as bad as reported.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
rrinkerDoes the curve have an effect? It has to, especially below a certain radius when the taper of the wheels can't compensate. But I don't think it's nearly as bad as reported.
I think when you talk about friction you have to consider all the factors. I don't think I've seen any calculations where the length of wheel base on the locos or rolling stock is taken into account.
rrinker This is where I have to call out the various formulas for grade compensation in a curve. According to one more relaxed version, the equivalent grade on that 16" radius curve would be well over 4%. Granted there is more friction for the loco drivers as well, but if that loco can't pull 1 car up a 3% grade, no way is it going to pull 9 up a 2.25% curve on a 16" radius curve if these compensation formulas are actually valid. I've always felt the exaggerated the effect of curves, but with no grades on my last two layouts, I had no way to test it. Here is some empirical evidence that curves as sharp as 16" radius do not nearly double the effective grade as the formulas would have you believe - One puts actual grade = grade + (28/radius), which makes the 2.25% actual grade into 4%, and the ogirinal formula is actual grade = grade + (32/radius) which would put the effective grade at 4.25%! Not a chance this loco could pull 9 cars up that if it can't pull 1 on a 3% tangent. --Randy
Decades later, the LDSIG (Layout Design Special Interest Group) started with John's formula and did additional testing using more modern equipment (and methodologies, from what I understand) and revised the formula to the first one you quoted: CG=G+28/R.
You're right that one car on a 3% grade doesn't match with seven (not nine) on a 3.95% compensated grade. Something else is different between the two situations (Bullfrog Snot?). Only Chip can tell us what the differences are.
Mark P.
Website: http://www.thecbandqinwyoming.comVideos: https://www.youtube.com/user/mabrunton
PruittOnly Chip can tell us what the differences are.
I think I was right before. The reason the coefficient of friction increases with a decrease in turn radius is that binding increases. If you are running engines that don't bind on a 16" radius, like the little 0-6-0, you don't get the increase in friction.
LDSIG, and I'm surmising now, had to have some testing standard to eleminate variables. For instance, they chose 3 representative engines, say a GP38, a 2-8-0, and a 4-8-4. and ran their tests. This would yield a plausable formula.
On my layout, I have only small steam and half that is geared. You can't expect the same results.
Edit: I tried to find the design methodology for the calculations on the LDSIG website, but was unable.
Hi everyone,
I just wanted to let you all know I'm alive if in some what diminished capacity. I have some sort of lung infection, although rest assured it is not the Big C or Little C for that matter. But I cough a lot of mucus and just slept 16 of the last 17 hours.
Other things are piling up as well, it's already started raining and I have a large portion of the exterior wall I need to stucco. Also, I got my book back from my editor and I have a lot of work to do with her on that.
Just saying the Rock Ridge Railroad is in suspended animation for the time being.
Finally, a chance for me to catch up......
...who am I kidding, you even have a train running, I don't even have any subroadbed in place, let alone track.
rrinkerFinally, a chance for me to catch up.....
Well. quit lollygagging.
It can't be more'n hunnert 'n fourteen!
(about all I can post from that scene these days)
SpaceMouse Hi everyone, I just wanted to let you all know I'm alive if in some what diminished capacity. I have some sort of lung infection, although rest assured it is not the Big C or Little C for that matter. But I cough a lot of mucus and just slept 16 of the last 17 hours. Other things are piling up as well, it's already started raining and I have a large portion of the exterior wall I need to stucco. Also, I got my book back from my editor and I have a lot of work to do with her on that. Just saying the Rock Ridge Railroad is in suspended animation for the time being.
rrebellYeah there are a few other bugs going around, sister just had one like yours.
Yeah, I got one like this 3 years ago. Hung on for months.
It's good news to hear, Chip. I have never had a lingering condition or illness, unless weight gain counts. Been there. I also know that COVID-19 can linger horribly for a few sufferers, and I have friends whose cold or flu seemed to have nasty effects for two or three months. You'll be very pleased to see the hind end of this one, for sure, and be glad to get back to enjoying living.
Hi guys,
Turns out I was wrong in my self-diagnosis last you heard. On Dec. 29, I was admitted to the hospital with a pulmonary embolism. The doctor in the ER said it was the worst they had ever seen and so they carted me off to a better faciity in Flagstaff where I spent 2 weeks in and out of the ICU. Turns out, the embolisms were caused by stage 4 colon cancer. I'm now on chemo--in fact, that's what I'm doing now. Fun stuff.
The good news is I haven't felt better in months, despite the chemo. And I seem to be getting better every day. Hopefully I'll be back working on the layout shortly. Sorry it took so long to post this.
Holy cow, Chip (get it? cowchip? haha)
Seriously, that's a big slap in the face! If it's not too personal, what do the docs say? Will you make a full recovery? Stage 4 cancer of any type is a big scare. My late wife died of stage 4 breast cancer a few years ago, and a friend died of colon cancer about 20 years ago.
Tell us they say you'll fully recover. Please.
Gosh, you come by here for a few years and suddenly you notice people sharing that they've had a scare....or worse. You probably don't know it, but we lost Randy Rinker to SARS-COVID two months ago. I'd say we won big if we've been able to reclaim you here, Chip.
So, are you still willing to run for Prez?
My Oncologist said I had maybe 2 years, but I don't buy it. I'm not reacting to Chemo like they expect. I feel better with each infusion, not worse. Side effects are lessening, not getting worse. As I said before, I'm feeling better than I have been since I started getting sick. I attribute this to eating a healthy diet--my cholesterol, blood suger, protien levels are all the rediculous levels pharmaceutical companies are calling normal.
That said, I had a CT scan and blood test for cancer markers last week and I will hear my results on Weds.
It seems more like a skirmish than a battle so far.
selectorYou probably don't know it, but we lost Randy Rinker to SARS-COVID two months ago
Aw DAMN!
selectorSo, are you still willing to run for Prez?
That just doesn't seem as fun as it used to.
I'll be praying for you. There have been huge advances in treatments the past years, so there's a good reason for hope.
York1 John
Hi Chip. Glad to hear you are back on board.
As my daughter says "Only knocked sideways. Never backwards."
As for anyone giving a timeframe. "Twaddle." I was given two weeks -- 74 years ago.
Just live life. People you haven't met yet want information and you are the only one they will listen to.
Looking forward to more instalments of the Rock Ridge Railroad.
Chip, Holy Moley! Yeah, self diagnosis can be hazardous, I recall taking that route with a heart attack, lucky for me my wife didn't buy it.
Best Wishes and regards, sincerely, Peter
Thanks for all the good wishes.
My latest CT scan showed no trace of the colon cancer, although the growth on my liver seems unchanged. The docs seem cautiously optimitistic. They ordered a PET scan later this week--but my oncologist is taking the month of June off, so I won't know the results until he gets back in July.
Terry
Terry in NW Wisconsin
Queenbogey715 is my Youtube channel
SpaceMouseThey ordered a PET scan later this week--but my oncologist is taking the month of June off, so I won't know the results until he gets back in July.
That's amazing that the colon showed no cancer.
I know nothing about medical issues, but it sounds like the doctor is not too worried if he is not in any hurry.
Hoping and praying for the best.
We'll grasp at any hope, Chip, as you would. I think I see enough positive to be hopeful, or enough hope to be positive....weird that it works either way. I wish you several thousands of sunny days ahead.
Great news for the most part, Chip!
Are they sure the liver spot is/was related to the colon cancer?
PruittAre they sure the liver spot is/was related to the colon cancer?
They assume it. It's common for colon cancer to metastasize to the liver.
However, the PET scan showed that the spot on my liver has diminished. My CAE test for cancer markers went from 100 in Jan. to 127 when started chemo in March and now is at 16.
[Knock on wood.] Things are looking up[/Knock]
Thanks everyone for your well wishes.
I haven't been following your thread as I don't usually follow layout builds.
Making a patient wait a month for PET scan results is cruel and unusual punishment. Surely he has someone covering his/her practice or could get off their (the prefered pronoun these days) caboose and check the results and tell theirself. And I say that having an MD behind my name.
And I never took more than 2 weeks off.
Henry
COB Potomac & Northern
Shenandoah Valley
Well, I'm back, I think.
I'm now on maintainance chemo--which looks alkmost exactly like the full blown version. The main differnce is they took me off oxaliplatin after my 8th infusion because I was developing neuropathy. I'm getting pretty much everything else that was on my chemo regiment--just now they are calling it maintainance.
The cancer itself appears to be gone. Latest pet scan shows no colon cancer. The mass on my liver's thickness cant be measured and appears as a thickning of the exterior liver membrane. My CEA (cancer marker) is down to 3.1 from 127 in Feb. 2021--5.0 being "normal."
The loss of feeling in my hands--neuropathy--is my major concern in terms of model railroading. I have trouble with things like buttons and zippers and I am dropping things. I'm worried about things that require fine motor skills like say fixing the itty bitty bitts on my Shay, installing decoders and lights, and detail work on, well, everything.
For that reason, I've decided that I might as well just jump back in the deep end, and see if I sink or swim. My first task is installing turnouts on my "hidden" staging.
Tomorrow, I'm scheduled for surgery to fix hemorrhoids and fissures in my anus, so I'll probably start eartly next week. So, my illness cost a year of work on my layout.
I'll keep you posted.