# Adventures in wheel slip



## rexcadral (Jan 20, 2016)

This post will only apply to live steamers with no track power, as I'm talking about actually applying stuff to the rails that definitely won't conduct electricity.

I run Code 332 brass track (USA Trains & PIKO) because it's easy to find here in the Boston area, and the robustness comes in handy when you have many small people around your house all the time.

Having started my adventure in Live Steam back in October, one of the first things I noticed was that my little 0-4-0 Roundhouse Sammie had lots of power, but very little grip.

I wasn't ready to add more weight to Sammie at the time, so I concentrated on the track. Here's what I found:

The pre-run oiling of Sammie's running gear using motor oil generally meant that the wheel treads got oil on them. - Not a huge deal for Sammie, but after a run, he definitely left a dark, oily streak on top of the rails.

Using a rag to clean off said streaks temporarily improved grip, until Sammie and train re-deposited 5W-30 back onto the railhead. - The pervasiveness of the problem and the fact that I picked live steam so I _wouldn't_ have to clean the rails constantly had me looking for other solutions.

When I initially laid the track, I had spray painted the rails brown. Investigating whether paint or bare metal affected grip seemed to favor bare metal, particularly after running my orbital sander over the entire track.

Well, the real thing uses sand for traction... so what can I use...

I stole a handful of beach sand from my kids' sandbox and poured/ground it into the rails at a trouble spot. - Most of it simply falls off, but some of the microscopic stuff sticks. - The result? Amazing traction! The bigger grains did result in some bouncing, but the improvement was remarkable.

Even good 'ole black New England topsoil works pretty good. - It does accumulate on the edges of the locomotive's wheels in the form of a muddy oil paste. - I needed something that was finer grained, and possibly "sharper".

The solution came from my wife, who recommended Diatomaceous earth - it is extremely fine, and looks like flour (technically you can eat it). Diatomaceous earth is composed of the calcified skeletons of sea microorganisms. We use it as an anti-insect barrier - the individual particles are very sharp, and they cut into the "skin" of 6-legged varmints, causing them to "bleed" to death. The "sharpness" and the extremely fine particles seemed like an ideal scale substitute for the silica sand used on the real thing.

I applied it with a simple bulb siphon which sent out gentle little clouds - the actual coverage of the rails was practically invisible, although it did "weather" my ties with clumps of white powder.

Did it improve grip? Absolutely! Currently I'm not sure if it did so because of the expected action of sand between two metal surfaces or because it soaked up the oil on the tracks, thereby providing more friction. More science required.

The puffing application and the fineness of the powder leaves me wondering if I could build an actual sand dome on a loco, and supply "sand" to the rails via pneumatics, either constantly, or on demand through a servo. I wonder if it's been attempted before....


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## Semper Vaporo (Jan 2, 2008)

Yes, it probably does improve traction, but I'd worry about the gritty powder floating up into the bearings and causing excessive wear. Washing the bearings (flooding with oil) before/after every run would not really reduce wear because the dust would be present during the run... and the excessive oil required to wash the bearings would just add to the amount on the rail compounding the problem.

Neat idea (and I'd love to see working sanders!   ), but probably not worth the destruction of the loco's bearings  .


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## Greg Elmassian (Jan 3, 2008)

Interesting experience.

Are you getting any caking on the wheels? Is it a manageable level?

I have seen warnings about that stuff, but apparently it's used in food, just don't breathe it a lot.

Yeah, I think it could work... real scale sanders!

I see the concern about dust in the bearings, it would really depend on how concentrated you could keep the "spray". If it could be done like in teflon tubes and little "overspray" then I would wager it would be like the real thing.

Greg


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## John 842 (Oct 1, 2015)

I would definately *not* add any abrasive material to the track - no matter how fine it was. Not only is the wear on the loco a consideration, but to a lesser extent, is wear on the track itself.

One of the great advantages of live steam for me is that the track requires absolutely no maintenance to the contact surface. In fact, if I havn't run for a number of weeks the oxides that form on the rail surface actualy combine with the oil that will inevitably get on the wheels and form a dark green layer that can work wonders for the coefficient of friction.

Of course it doesn't always happen because it's dependant on how much oil is on the wheels and how much oxide is on the track and it won't happen at all with stainless rail. 

In that case I make sure that there is a minimum loading on the non-driving wheels consistent with stable running and it doesn't matter what the weight distribution is for the coupled drivers since friction is independant of area of contact.

And if that doesn't work - then I just add weight untill the problem is solved.

Don't forget that full sized locos suffer from wheel slip and managing it in just the same way as the full sized guys do is all part of the fun - provided you have radio control on the regulator and you don't resort to the sanders ....


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## rexcadral (Jan 20, 2016)

Semper Vaporo said:


> Yes, it probably does improve traction, but I'd worry about the gritty powder floating up into the bearings and causing excessive wear. Washing the bearings (flooding with oil) before/after every run would not really reduce wear because the dust would be present during the run... and the excessive oil required to wash the bearings would just add to the amount on the rail compounding the problem.
> 
> Neat idea (and I'd love to see working sanders!   ), but probably not worth the destruction of the loco's bearings  .


Probably not a concern the way I'm manually applying it now. The loco is nowhere near the area of application when I puff the stuff onto the tracks. If I were to build an actual sander, I'd probably use some very fine 1/8" tubes to deliver the sand to the intersection of the wheel tread and the rails with very little pneumatic force - just enough to move the sand through the pipes. On the real thing (I ride commuter rail every day) there's little metal guides on each side of the pipe that channel the flow onto the track, not under the loco or off to the side.


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## rexcadral (Jan 20, 2016)

John 842 said:


> I would definately *not* add any abrasive material to the track - no matter how fine it was. Not only is the wear on the loco a consideration, but to a lesser extent, is wear on the track itself.
> 
> One of the great advantages of live steam for me is that the track requires absolutely no maintenance to the contact surface. In fact, if I havn't run for a number of weeks the oxides that form on the rail surface actualy combine with the oil that will inevitably get on the wheels and form a dark green layer that can work wonders for the coefficient of friction.
> 
> ...


John, considering so many people recommend using drywall sanders to keep their rails clean enough for power, I doubt I'm doing anything serious to the life of the track, or the steel wheels on anything that rolls along them. - I'm not "polishing" the track, just putting grit on it. I'm guessing at a microscopic level, the grit fills in pits on the track and also interfaces with pits in the wheels to produce better traction - in theory this is all static, so there's very little rubbing going on.


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## Semper Vaporo (Jan 2, 2008)

rexcadral said:


> Probably not a concern the way I'm manually applying it now. The loco is nowhere near the area of application when I puff the stuff onto the tracks. If I were to build an actual sander, I'd probably use some very fine 1/8" tubes to deliver the sand to the intersection of the wheel tread and the rails with very little pneumatic force - just enough to move the sand through the pipes. On the real thing (I ride commuter rail every day) there's little metal guides on each side of the pipe that channel the flow onto the track, not under the loco or off to the side.


I detect wear just from the dirt on the ground that gets kicked up by the passing loco... adding to that dirt with abrasive grit is not something I'd do.


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## chuck n (Jan 2, 2008)

Rex

What is the diameter/radius of your curves? I'm inclined to think that your black oily substance that builds up on the rail head is very fine pieces of brass from your track. Very fine grained pieces of metal looks black and oily. Your drivers are a harder metal than the brass rail and they will slowly grind away the brass. The tighter you're curves, the more grinding.

Several years ago we had a discussion here in MLS about the black that is found on the top of our rails.

I carefully cleaned the wheels on an engine and my track (10' diameter curves). I ran the engine around the loop for about an hour, as I remember. I then wiped a section of track with a clean paper towel. I gave the soiled towel to a colleague of mine for analysis. The particles contained copper, zinc, and lead; otherwise called brass.

Your slipping wheels will grind the rail top. If left to long you will have a divot on the top of your rail. Over the years I have developed several divots on my track, when something happened and I wasn't paying attention.

Chuck

A couple more questions. How much does your engine weigh? I have measured the tractive effort of a number of engines. On average they can pull about 1/3 of their weight, some a little more some a little less. That is not the weight if the cars, but their drag.

How many cars are you pulling and what are your grades, if any? Do the wheels slip all the time, or just at a few spots? If that is the case where on the layout does that happen?

One last comment. Diatomaceous is NOT calcified micro organisms. They are micro sea creatures that make their shell out of silica. Calcium carbonate has a hardness of three. Silica can have a hardness that is between 5.5 and 7, glass is about 5.5 and Quartz is 7. Many metals have a hardness that is less than 5.5. Materials with a higher hardness number will scratch, polish, abrade, or grind away materials with a lower hardness number. 

You do not want to get diatomaceous earth into your bearings and other working parts of your engine!


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## rexcadral (Jan 20, 2016)

chuck n said:


> Rex
> 
> What is the diameter/radius of your curves? I'm inclined to think that your black oily substance that builds up on the rail head is very fine pieces of brass from your track. Very fine grained pieces of metal looks black and oily. Your drivers are a harder metal than the brass rail and they will slowly grind away the brass. The tighter you're curves, the more grinding.
> 
> ...


Hi Chuck,

The loco weighs ~6lbs when it's full of water.

My curves are 8ft minimum radius. Anything that rolls on my railroad has metal wheels so there's no plastic component to track grime. 

I just spent the weekend reducing my grades (my track is up on posts) and Sammie will pull 6 cars, most weighing around 4lbs with both metal wheels and metal trucks.

When I re-graded, my goal was to get the loco to pull 6 cars throughout the RoW at low speed without wheel slip. - A tricky proposition since it's a 4-wheeler and has no equialization. I figure the grades are 1-2% at present. For its weight, we are certainly approaching maximum tractive effort. I had great weather this weekend, ~50 F, and dry, so traction was ideal.

The sanding has become something of a curiosity at this point, it's not an attempt to solve a mechanical flaw or a grade problem, it's just for fun, and like the real thing, it appears to have its place.


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## du-bousquetaire (Feb 14, 2011)

I would not advise using abrasives on the wheels of your loco, as it is bound to wear the mechanicals of it down. I used to run in rain, I don't any more because I cleaned out the bearings on my Wilags once. They were full of mud it came down the wheel face into the journals when the cars would stand still and bring in dirt picked up on the rails. My track is on concrete but ground level. 
I agree with John that the muck that accumulates on the track when you run live steam really helps adhesion. Now when I hold a Get together on my pike, I don't clean the rails before as I used to, it helps reduce slipping. That is one of the pitfalls of track power. You can't have it all!


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## chuck n (Jan 2, 2008)

Rex

There will be track wear with 8' diameter curves, I had it with 10' d curves. 

It is not how much your cars weigh, but the friction in the journals. Do you know any fishermen? If so, borrow his scale and see what the drag of the 6 cars is. Try lubing the journals of the cars with graphite or add ball bearing wheels (expensive, but will significantly reduce drag).

Here is a picture of a couple of my track divots.










here is a picture of divots that was sent to me.











While you were typing your comment I added a paragraph to my previous post about NOT using diatomaceous earth and why.

Chuck


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## Greg Elmassian (Jan 3, 2008)

I'd advise reading this: http://www.livestrong.com/article/510749-dangers-of-taking-diatomaceous-earth-internally/

before you determine how abrasive the silica component is or how dangerous. For those who do not read the link, "Crystalline silica forms when diatomaceous earth is heated to very high temperatures,"

Also please notice it is used in foods and medicines.

So, I would think that a controlled release on the rails is no more detrimental than dust on the rails. 

It's not the same as a wheel splashing in dirty water, unless you are spraying it in the bearings. 

So, I'd see if controlled release in the right places is possible, pretty intriguing idea.

Failing that, pushing a car ahead of the loco dispensing it might also be an option.

Greg


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## chuck n (Jan 2, 2008)

The hardness of opal is 5.5 a 6.5 on the MOHs scale. The shell of the diatomites is a very similar composition to opal. You wouldn't put sand in your crankcase and you wouldn't want diatomites in the moving parts of your engines and cars. 

Chuck


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## rexcadral (Jan 20, 2016)

chuck n said:


> The hardness of opal is 5.5 a 6.5 on the MOHs scale. The shell of the diatomites is a very similar composition to opal. You wouldn't put sand in your crankcase and you wouldn't want diatomites in the moving parts of your engines and cars.
> 
> Chuck


Not to be a nudge, but the Sparky drivers have to use _something_ abrasive on their tracks periodically, let's assume fine-grade sandpaper, which is likely made with aluminum oxide, or zirconium - putting it in your 5-7 Mohs range. They're _dragging_ this paper across the track. I'm just rolling over it.

I figure it would be equivalent in terms of wear & tear. - I don't know about you, but I would think it would take a lot of mileage to put a dent in 360 Brass, which (based on Mohs for gold & copper) is probably at least a 3.

Based on my reading of Gary's and Greg's blogs, those enormous pot-holes in your picture probably had to do with holding back a seriously over-powered sparky (USA Trains anyone) long enough to do a lot of damage. I'm trying to prevent exactly that kind of wheel spin. Considering we've got 2 pages of people complaining about dirt in their bearings, I don't see how avoiding this would matter.

Maybe I'm new/young enough to not appreciate some wear & tear on equipment - brass bearings are pretty easy to fabricate in a pinch, if I didn't have extras lying about. If my loco made those kind of divets, I"d call that an act of nature and replace the foot of track (mounting the artifact on the wall of my workshop... that's a keeper)

Why look at sanding? Because it's a challenge, and challenges are fun.


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## chuck n (Jan 2, 2008)

I would never use any of the abrasives you mentioned. Too many scratches to collect dirt. 

I use a green scotchbrite pad to clean my track. No dust, no stratches on the track. Just a polish.

Go for it and keep us informed as to your progress.

Chuck


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## rbednarik (Jan 2, 2008)

Alloy 360 brass will wear out faster than you think. Even Alloy 544 or 642 Bronze will suffer if fine silica is introduced into the bearing surface. 

However, the axles may be the bigger wear factor. Especially true of roundhouse axles is the susceptibility of the axle to wear as the grit embeds itself into the axle bearings and then acts as a grinder/cutter into the steel (stainless) axle, causing it to groove. 

I suppose though, for experimental purposes, it is worth a try from a cost-risk analysis as bearings and axles/crank pins are all replaceable.


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## Chris Scott (Jan 2, 2008)

Dave Hottmann has a Ruby that will pull a string (10+ ?) of heavy weight passenger coaches or 40+ freights with ease. His Ruby, last time I saw it, weighed maybe 20 pounds, seriously, or seriously close to 20, maybe more. He had every crevasse stuffed with lead - lead fishing weights and auto tire balance weights of any size needed to fill whatever cavity. Who knows by now he could gone to replaced it all with molten lead for just that little more weight. He's been adding weight to it for years just cause it was ridiculous fun  to see the absurdity of an 0-4-0 pulling yoooouge weight. You can go back through year's past NSS or DH videos finding several videos of Dave's Ruby in action. 

Just MHO...
Anyweight, go back and add weight to the loco and forget degrading the track so little loco weight acts like lots of loco weight. Seems to me it's kinda counterproductive.  The small benefits seem marginal and you wrote you rebuilt parts of your layout as a result for 6 cars. And no matter how much you think the power or dirt or whatever won't affect the loco, it will, a lot. You won't notice it until its really done a job because you will be oblivious to the slow incrementalism of it. 

More opinion... 
Lost seems to be the benefits of reducing the rolling resistance of your cars. Superlube-ing the axles works for me it's thicker so it stays in place longer, maybe use some type of grease but I've never gone that route. Extreme would be ball bearing wheels but well short of that (cost) is adding bearing bushings. Once upon a time Phil Dippel had/has a service adding the bushings to trucks. Don't know if Phil still does or if anyone else offers the service. It's not that hard a diy and I'm sure numbers here can advise on sources for the inexpensive bushings, as well as best and easiest ways of dyi-ing it. 

Here's a link to Phil's web page on adding bearing bushings to trucks and the steps involved. http://www.philsnarrowgauge.com/Services.html

Happy rollin'


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## fkrutzke (Jan 24, 2008)

One of the more respected posters here got fine silica dust into the journals, he has an extensive ground level track, and the silica imbedded itself into the softer bronze of the bearing and significantly wore down the steel axles. His only solution was to replace all the bearings and axles, a very big job. The journal got sealed ball bearings inserted for replacement bearings.


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## rexcadral (Jan 20, 2016)

*All lubed up*

All my trucks are lubricated with white lithium grease, which gives outstanding performance on my all-metal USA Trains trucks, and actually turns better than my Roll-EZ wheels, which have ball bearings.

I have reduced my grades considerably, and I think 20lbs is pretty respectable for a loco - I had the pleasure of walking into Charles Ro and handled their 0-6-0 docksider, which has to weigh at least 20 lbs - I couldn't believe how heavy it was.

Someone in this thread meantioned a 20lb Accucraft Ruby, which is amazing, but leaves me with questions:

1. Did they still have the stock cylinders, or did they port them out to 1/2 inch?
2. What pressure were they running? Accucraft seems to like running at 60lbs, whereas Roundhouse runs on 40lbs - with a 7/16" bore.
3. What's the stroke on those things? I wonder what the crank offset is, and the wheel diameter.

Basically, assuming the track is level and traction is ideal (weighted loco, what have you) how many cars does it take to stall a steamer?


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## Gary Armitstead (Jan 2, 2008)

rexcadral said:


> All my trucks are lubricated with white lithium grease, which gives outstanding performance on my all-metal USA Trains trucks, and actually turns better than my Roll-EZ wheels, which have ball bearings.
> 
> I have reduced my grades considerably, and I think 20lbs is pretty respectable for a loco - I had the pleasure of walking into Charles Ro and handled their 0-6-0 docksider, which has to weigh at least 20 lbs - I couldn't believe how heavy it was.
> 
> ...












Rex,

I have very little experience with these garden variety live steamers, but I DO have 35 plus years experience in running 1-1/2" scale steamers AND pulling heavy trains. 

In the photo above, I'm sitting on our 1/8th scale Allen mogul. My sitting position in this photo is where I would be when pulling a public train with four gondolas and a brakeman's caboose. Each gondola carries three adults. Total passengers for the train (including engineer and conductor would be 14 adults. Average weight per adult at 175 pounds....2450 pounds. Weight of the engine 450 pounds, weight of the four gondolas at 175 pounds each, caboose at 125 pounds. Total weight of train, 1350 pounds (including water and coal).. Total train weight 3800 pounds. This little mogul has a 2 inch bore by 3-1/2 inch stroke. Fairly small cylinders for a steam engine in this scale. Want to know how we can haul this kind of weight including some areas of the LALS layout which are 3-1/2% grades. Very simple, it's not the weight of the engine........it's WHERE that weight is centered.

I over-exposed this photo so you could see the drivers and the wheel arrangement on the tender. If you look close at the connecting link between the engine and the tender (at the end of my right shoe toe area), that link extends back under the frame of the tender to about the center of that frame. The front truck on the tender just "floats" there. There is very little weight supported by THAT truck. If we encounter a steep grade, we just shift our sitting position toward the cab about two inches and then our weight is transferred toward the last pair of drivers. We go right up a 3-1/2% grade without any problems. We can actually do these grades at a walking pace and just creep up the grade. It's all about weight transfer. Nothing done to the track or the drivers to enhance pulling power. When we reach the top of the grade, we just move back a couple of inches in a normal sitting position.


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## rexcadral (Jan 20, 2016)

@Gary Armistead - Fascinating. Does the draw bar go around the bolster of the front tender truck or is the tender truck mounted to the draw bar?

I had a few thoughts around this line when considering building my own engine/tender - I wondered if the location of the draw bar joint on the loco could have a negative impact on traction by torquing the loco's nose up, similar to what happens when you step on the gas in a car. I had been thinking about mounting the draw bar joint in-line with the centers of the driver axles, or perhaps even lower, figuring that tension on the draw bar would actually torque the loco body _downward_ onto the drivers.


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## du-bousquetaire (Feb 14, 2011)

I agree totally with Gary and as luck would have it it connects with another thread which I am contributing to these days the one on, the Chapelon Pacific by Aster. This loco has compound motor therefore four cylinders up front and accompanying pipework and valve gears and rods. However it does not have a true locomotive boiler but a JVR type C boiler meaning a dry firebox. Compared with the 2-3-2 U1 which does have a true locomotive firebox. It slips madly because of all the weight in the nose is not compensated by the heavy weight of a true loco type firebox in the rear. So what Aster did was to but a notch in the frame of the loco that in effect puts all the weight which should be on the front driver onto the front truck! if you dont want it to slip you have to fill all that you can, around the firebox and cab, as well as the ash box with lead to balance back the engine which because of that doesn't have the performance of the hudson (U) although it has basically the same motor. So where you put the weight is most imùportant in regards to adherence. Don't forget that a PRR J1 or Q2 was had more tractive effort than a challenger and almost as powerful as a big boy; the difference in weight alowed per axle did a lot to permit that...


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## Gary Armitstead (Jan 2, 2008)

rexcadral said:


> @Gary Armitstead - Fascinating. Does the draw bar go around the bolster of the front tender truck or is the tender truck mounted to the draw bar?


As I mentioned before, the draw bar is an integral part of the tender frame. Think of it this way.......if we remove the front truck on the tender (the one closest to the engine cab), we could STILL ride on the tender and run the engine! Bear in mind that we had to beef-up the engine frame and the tender frame to do this. Some stock had to be removed from the truck bolster attached to the frame, so that when we are seated in a "normal running" position on the tender, the truck bolster and tender frame bolster have more clearance than would normally be there in a typical tender. This amount had to be part of the calculation so that when we are seated closer to the cab, we get the appropriate amount of load transferred to the rear drivers. To answer your question, NO the draw bar does not go around the bolster. It is actually PART of the bolster and frame.


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## steamermeister (Feb 20, 2013)

I use chalk sticks to "line" the top surface of the rails in areas with wheel slip. It's probably easier to control the location and amount of powder that gets laid down than with a bulb siphon. It's also probably less work because a chalk stick is ready to go as is.


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## KeithRB (Sep 25, 2015)

As far as diatomaceous earth being a health hazard: It could be a lot like the beryllium oxide I am familiar with. It is perfectly safe to eat, but when the particles are a certain size and you *breathe* them, they scar the lung tissue and cause a lot of damage.

This could be why they are trying to move to "non silicon" sand for playgrounds.

http://www.quikrete.com/PDFs/MSDS-B4-Playsand.pdf


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## rexcadral (Jan 20, 2016)

steamermeister said:


> I use chalk sticks to "line" the top surface of the rails in areas with wheel slip. It's probably easier to control the location and amount of powder that gets laid down than with a bulb siphon. It's also probably less work because a chalk stick is ready to go as is.


That's an awesome idea. - And that's calcium carbonate rather than silicon, so it has a lower MOHs rating, and will probably do less damage to the brass.


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