Frequently Answered Questions for rec.models.railroad


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Introduction

25 May 94 14:00:00 GMT

This digest contains the following parts:


Kits, Bowser

21 Mar 94 01:00:00 GMT

I've read about the Bowser kits. How difficult are they?

Building a Bowser steam engine kit properly does require a substantial amount of effort. First, all of the castings (boiler, frame, cylinders, tender, etc.) require a great deal of filing to remove flash. In some cases extra metal must be removed and holes may have to be relocated for parts to fit properly.

Another step that is not necessarily difficult but does require patience is riveting together the valve gear. It is also tricky (and important) to get the valve gear to operate smoothly so that your engine runs smoothly.

You must also of course paint the unit. Bowser recommends to first completely assemble and run the model to make sure there are no operational problems. Once satisfied with its running characterists, the model will have to be at least partially dismantled in order to paint it.

The "super detail" kits that Bowser sells contain a collection of brass (?) castings. In some cases, the brass castings are to be used instead of metal castings supplied in the standard engine kit. Examples of this include: the generator, bell, and power reverse mechanism. Of course, there are many parts not included in the standard kit such as the injectors, marker lights, and tubing (which must be bent from straight wire). I suppose that if you add up the prices for all the parts in the "super detail" kit you would find that the kit is a better deal than buying the parts separately. You have to decide yourself whether or not you want to buy this kit. The engines will certainly look nice without it, but the engine will look much better with the super detail kit.

Once completed, a Bowser steam engine will be one of your most powerful engines. This is mainly due to their weight -- they are quite heavy.

To answer your specific questions...

I usually spend a couple hours a night building a kit like this. In doing so I finish in a couple weeks. Tools I find useful include:

If you are considering a "super detail" kit I would recommend that it be purchased with the engine kit.

PS. The Bowser kits do not come with an illuminated headlight. However, with a "grain-of-rice" bulb (I recommend the 12 volt), it is easy to add one.


Styrene, glueing

21 Mar 94 01:00:00 GMT

I'm installing a bridge on my layout and am having some difficulty glueing the styrene bridge piers (back and bottom) to the wood base. Any and all suggestions would be most welcome.

Walther's Goo seems to be a good all around adhesive. Be sure you don't use too much, cause Goo will warp plastic and remember that it dries in a deep orange color, so you may have to paint it after it dries up.

...

I have used a "white mastic" type glue for this type of thing. I forget the brand, but you can buy it at Color Tile. The things I like about it, are that:

  1. you only need a TINY drop (like cyanoacrilate glue), and
  2. it dries milky-clear.

Laser cutting

28 Jun 94 01:00:00 GMT

While thumbing through RMC and MR I noticed a marked increase in the number of craftsman kits that now include "laser cut" parts and it occured to me that I don't really know what this means. Yes...I do know that it means a laser is used in some fashion to cut to very exact sizes, but what technology is being used? For example, is the laser mounted in a plotter head? Is it 2-D mirror controlled? Does it cut multiple goods at once? Is it driven from some CAD system?

For a change this is something I can talk about without going to a book for reference. For the past several years I have worked on using lasers for manufacturing in the electronics industry. I can tell you that they are probably using a CO2 or Nd:YAG laser which is focused to a fine point at the part to be cut. Both emit light in the infrared part of the spectrum and cut by heating the material to boiling point and evaporating or melting through.

There are two methods used to cut the pattern, either the laser beam is moved using mirrors or the part is moved using a X-Y positioning table. The choice depends on the cutting speed and the area to be covered. Directing the laser by mirrors is very fast but has a limited work area. Probably the second method is used where a large x/y motion table is used.

This system has the advantage that a large sheet could be put in the machine and multiple parts cut from the one sheet unattended. The pattern is almost certainly designed on a CAD system and downloaded to the laser cutting workstation. The X/Y table is then computer driven based on the CAD drawing.

It may be possible to cut multiple layers at once but the possibility of debris from the cutting process depositing on the other layers might discourage its use. The other drawback to multiple layer cutting is that the layer the laser is focused on would have the best cut, the other layers would have cuts of lesser quality. It all depends on the quality and look the manufacturer wants in the finished parts.

...

I would like to comment on Laser Cutting. I have not seen the any of the kits with "laser cut" parts but as I have been involved in designing photo-etched (chemical milled) brass kits for some years I have been watching the advent of laser cutting with interest. As I see it the two techniques are complementary. Photo-etching is not really practical for metal thicknesses over about 1mm so is used for the smaller scales, while laser cutting, is which is much more expensive, is used for the model engineering scales (G1 and above). Of course you can't etch wood at all, or plastics easily, so lasers could be used on these materials, but at the prices I been quoted 1 a foot run makes it a speciallist technique, at least in this country.


Painting, Accuflex

21 Mar 94 01:00:00 GMT

What should I know about Accu-Flex paints?

I managed to track down some Accu-Flex at the Train Shop in Santa Clara, CA. on a recent trip, and used it to paint a Rail Power Products Dash 8-40CW cab last weekend. I sort of made the exercise a torture test, mostly to see what I could do or not do with Accu-Flex. First of all, I had never painted anything with an airbrush other than sheets of styrene while fooling around -- the cab was the first "real" model I've airbrushed. I sprayed the Accu-Flex unthinned from a Badger single-action, internal mix airbrush, running off a borrowed Badger compressor (thanks, Dave!). The Accu-Flex bottles attach directly to the airbrush -- no pouring paint back and forth. I sprayed UP Armour Yellow with good results -- the paint covered well and I was able to achieve good coverage in a single session. Even on a small item like the cab, I was able to spray the sides and work back to the beginning to spray over the initial pass because the paint set very quickly -- multiple passes with no runs. I waited about two hours and masked the cab with 3M Magic Tape (I said it was a torture test :-). I sprayed the UP Gray over the yellow and got good coverage over the first color coat. I peeled the tape as soon as I capped the paint and washed out the airbrush.

I wound up with a small parting line on one portion of the cab, but that was because I sprayed twoards the tape boundary instead of over it. Othere than that, I couldn't see any parting line with the naked eye, and none of the cast-in detail was obscured at all. I did get some spatter in the yellow, which I attributed to low air pressure. SInce the biggest objection to Accu-Flex seems to be that you can't take it off once it's on, I called Badger's marketing department to see what they recommended. Badger referred me to the guy they bought the paint from, so I called the manufacturer (a guy named Greg Konrad).

Mr. Konrad was very helpful, suggesting a mixture of two to three ounces of liquid Spic and Span mixed with about an ounce of ammonia in warm water. Let the part sit for 5 - 10 minutes and scrub off the paint. This mixture worked very well -- I scrubbed the paint off the cab with an old soft toothbrush. Paint removal was good, although there was a small amount of color left around some of the raised details. I don't expect it to be a problem because of the thinness of the original coat. Mr. Konrad also said that he recommended spraying with a single action, internal mix airbruah, using 30 PSI, at about 4 - 5" from the surface, a recommendation echoed in the Model Railroading review.

This means there's a problem using the normal hobby compressor, because most of them only operate at around 20 PSI, and you really need the higher pressure -- Mr. Konrad's quote was "water is heavy, you really need to push it." I expect that could cause problems for a lot of folks, but I'm using an airtank with a filter and regulator for now, with a shop-size compressor to follow. (I'd rather spend the extra money and get full shop air for tools, etc. than invest $150 in something I can really only use for airbrushing.)

Bottom line? It looks like great stuff to me. A beginner (me) put it on easily and effectively while just about trying to make a mess of it. It doesn't smell, the vapors won't cause bad things to happen to your liver or bone marrow, and cleanup is soap and water. You still should probably use a spray booth (to keep overspray and airborne dust and crud off the model), and a filter mask (to keep overspray and crud out of your lungs). I don't know what the professional and semi-pro folks will think of it, and I don't know what the availability will be like (it took a while for SMP Accu-Paint to be a regularly stocked item). I'll be happy if I can find it on a regular basis so I can skip the solvent-based stuff, or messing with water and Photo-Flo with the Polly-S paint.


Painting, airbrush, Accuflex

21 Mar 94 01:00:00 GMT

After numerous applications using different air pressures with my Paasche model H (single action brush) the best finish that I could achieve [with Accu-Flex paint] was a slight semigloss white finish on the side of my HO scale 48' A-line intermodal container. What went wrong?

I had the same problem when I tried at < 30psi, or had the needle pulled back in the position I use for Floquil or Scalecoat in my single action airbrush. When I reduced the flow , things started improving. When I pushed the needle so far forward I couldn't believe any paint could get through, sure enough, it did, and it worked amazingly well. The stuff likes to be sprayed amazingly thin, and is amazingly opaque. Thicker and it really glops up. I soaked a ruined paint job in brake fluid until I got it off, and tried again -- and got it right. I see why the reviews caution against double action airbrushes--the normal range of motion is way too large. 1/4 or less of the needle's travel is all you'd need, but that's too hard to control. I expect badger will be coming out with a "small movement" double action brush soon...

I got some on my fingers, and unlike floquil, it took a week to wear off.

I also like handpainting with the stuff. the stuff thins like watercolors, but is much more opaque. In full concentration, it flows as well as floquil and dries much faster. It mixes predictably, but you have to be quick or it'll dry out on your palette. About 30% water slows it down enough to be more usable, without thinning it so much that it runs when brushing. It's weird to spray thicker paint than handbrush... the thing I haven't figured out yet is how to drybrush -- it dries on the brush before I can use it. I bet there are some new tricks I can do for which watercolors are too thin.

The things I like most is the lack of noxious chemicals (it does smell, but compared to any other paint I've used, negligable), water cleanup, (be quick or it'll paint the inside of your airbrush!!) how fast it dries enough to be handled, and how thin an opaque coat can be. What I don't like are the problems created by how fast it dries, and the absense of certain colors I have come to expect in floquil: metalics, depot buff, roof brown, boxcar red (they must...but what's it called?) I too have a big compressor (I recently used it to wetsand the bottom of a sailboat--no electric sanders for that job!) so I don't mind the high pressure requirement.

...

Well, I posted a quickie about a month or so ago, and my experience was also negative, BUT after playing a bit more, I've changed my mind.

My main problem with my first experience was too little pressure (about 25 psi... where I spray Scalecoat...). It caused the stuff to dry *really* fast... I found myself "blipping the throttle" while turning the loco around, to keep from clogging. This was with the "Light Tuscan Oxide" color.

The second experience was with "DM&IR Maroon". I bumped up the pressure to 35psi, and it sprayed better, but still not well. I did like the finish much better this time, though.

The third experience was last night with the DM&IR maroon again. I decided to give it the "best possible conditions"... aka I completely diassembled the brush and cleaned it before use. It had months of scum built up, as I expected. This time I also followed a friend's advice by painting a very thin coat before the main coat. This is because the paint will tend to run more than most. This is caused by the fact that it's not etching the plastic. With the dry coat, you can lay a slightly heavier color coat. It should be noted that by the time you're done shooting the light coat, it's dry on the first side, and you can carry on.

My fourth experience was a brush-painting of some details with white. This is what blew my mind. The paint is incredibly thin to work with, yet it covers like nobody's business. It is in this use that I wouldn't recommend anything else.

Overview
My experiences have been increasingly good. Basically it's a need to modify old techniques to use with the new paint. The pressure *must* be at about 35, and it's probably not a good idea to paint at less than room temperature (water-base paint would probably be more delicate with temperature.)

Cleaning is a little more of a problem, it takes more time. BUT, you are NOT spending this time playing with toxic, flammable chemicals. Also, the neatest thing is that by the time you are done cleaning, you can pick the models up and go upstairs... they're dry enough to handle within 5 mins.

Remember, this is coming from the writer of the R.M.RR FAQ's brass painting guide!

...

This may or may not apply to you also. A local modeller was having a similar problem with the paint and contacted Badger. Seems some early batches of paint slipped out that were too thick and need to be thinned up to 30% with water. The difference can be noticed when shaking. If if it sounds like Accupaint (or floquil, etc.), then you don't need to worry. However, if it sounds like you're shaking a bottle of syrup, try thinning it. I had two bottles (primer and antique white) that needed thinning and worked great afterwards. Again, this may not apply to you.


Air compressors

21 Mar 94 01:00:00 GMT

What should I know about air compressors?

Getting one with an airtank attached is preferable otherwise you'll be running it continually. I recommend whatever one you get has a bleed-off relief valve.

Regardless of what you buy get an oil/moisture filter/trap and a regulator. Air pressure will vary from airbrush to airbrush; medium used; viscosity; and, temperature and humidty factors present when spraying.

...

My personal preference is to pump the air tank up to about 50psi then bleed it off at 8-25psi as required. It helps to have the water trap as close to the airbrush as possible. A hose about 6 feet long from the tank to the water trap, air filter and regulator, then the thin hose to the airbrush. It is advisable to have two pressure gauges, one showing the pressure in the tank and the other showing the pressure through the regulator.

You might like to see Airbrushing For Model Railroaders (I think it's Kalambach Video).


Painting brass

21 Mar 94 01:00:00 GMT

How do I paint this $1,200 brass model I just purchased?

Well, being handy with an airbrush is the "only" place to start playing with brass... if you don't already have some experience... practice airbrushing on some less-expensive (and less detailed) stuff.

My [Dennis Lippert] "system" for painting brass steam locos has always been basically the following:

  1. Test-run the loco... to make sure it ran before you took it apart(!). Check all of the valve gear and rods for loose screws, tighening if found. It might even be a good idea to fully break-in the loco before putting it through the "trauma" of disassembly.

  2. Disassmble as follows: remove lead & trailing trucks. Detach the boiler from the frame. Install the weight (if it was just wrapped up and sittiing in the box). Remove the trucks and couplers from the tender, and remove its body from the frame also. If the smokebox front is removeable, you might want to take it off also. This *should* be all the disassembly that will be necessary.

  3. Inspect the model. Fix anything broken, and check out the factory clear-coat lacquer. If the lacquer seems to be smooth and isn't chipping off, use it as a primer for your paint. If the lacquer is no good, strip the loco (I use ScaleCoat's stripper).

  4. Wash the loco with soap and "water as hot as you can stand". This is to make the surface clean so the paint will stick better. Don't worry about getting the motor/drive wet. As long as it dries completely before putting power to it, it will be OK. Let the model dry for at least a few hours, preferably overnight. After washing the parts, always wash your hands before touching the model (or better yet, wear rubber gloves).

  5. If the loco was stripped, it needs to be primed. I use a PPG two-part epoxy primer (because a friend got it for me), code-named DP400/DP401. You mix equal parts of the two bottles, let sit for 30 minutes, then thin with lacquer thinner and spray (it will only last a couple weeks in the bottle after being mixed, so don't mix much). It should be noted that Floquil's "primers" are basically just paint colors with thicker pigment (for sanding). They DO NOT adhere to the surface any better than the normal paints (this from a PPG paint chemist who has "chemically dissected" them).

  6. Prepare your paint. I like Scalecoat II because of it's good coverage and shiny surface. You get the best smoothness if the paint is slightly on the thin side, rather than slightly thick. But just *slightly*. (if Scalecoat is overthinned, it will chemically "fall apart".

  7. Adjust the airbrush to spray a very small amount of paint. Our first area of attack will be the chassis. Connect power leads to the frame and the drawbar, and put about half-power to the chassis. Hold it by the motor (assuming can motor), and spray all of the stuff that's moving, from various angles. sit the chassis aside, upside down, and leave it running for five to ten minutes (to make sure the paint doesn't stick anything together when it dries.) Since the airbrush is turned down right now, we can also spray the lead truck, trailing truck, tender trucks, etc. Be sure to hit them from many angles, and to roll them around while painting them. ( A skill in itself... hitting a moving target! :-) Possibly the single biggest trick in airbrushing brass is getting paint on everything that will be seen (a bare spot under a detail on a black plastic loco looks like a shadow... on brass it looks like someone forgot to paint it!)

  8. open the airbrush up to a "normal" spray pattern. Start to spray any part (boiler, tender, etc.) Begin by spraying from obscure angles around all details. Then come back and lay a smooth overcoat over the entire area.

  9. once done with the main body parts, you can come back to the chassis. Spray all non-moving parts with the "heavier" spray pattern. Try to avoid spraying on the moving parts (since they're already painted). Again, the motor is the nicest handle to hold with.

  10. Now you should notice that everything is painted (unless I missed something). In the case of a PRR steamer, the boiler and tender body should be brunswick green, the chassis components should all be black. Take some time to look at all the parts from any angle that you can... there WILL be bare spots somewhere (trust me!)

  11. Wait for things to dry. With Scalecoat I paint, this can take days to quit being tacky. Suggestions to speed drying include: The best idea is to do one of the above to remove the tackyness, and still let the parts sit for a week. This guarantees that everything is dry and hard.

  12. prepare for next color(s). On most steamers this would include graphite smokeboxes, Oxide red tender decks/cab roofs, etc. Check your prototype! Mask carefully, but prepare yourself for the fact that you will get overspray under the masking. Luckily, black is easy to touch up. Always "overdo it" with metallic colors, and cover up the overspray later. The metallics are incredibly hard to touch up without it showing, so make sure everything that is to be metallic gets sprayed the first time.

  13. Apply next color(s). Using a very low pressure (10-15 psi) to keep overspray to a minimum. Remove masking as soon as you are done. "Bake" again. [You can often do two or more "extra" colors at one sitting... as long as they aren't too close to each other on the model (overspray problems).]

  14. Clean paint from parts which must make electrical contact. These include tender truck bolsters, wheel treads, drawbar, etc. with lacquer thinner and Q-Tips. The engine drive wheels are easiest to clean if you again run the chassis on a power pack.

  15. Reassemble the loco. After reassembly, do any kind of touch-up work and details. (i.e. if you did a graphite smokebox, the railings, etc. will also be graphite, so repaint them [black]).

  16. Dullcote the loco (or semi-gloss) after decaling. This will seal the decals and give "an extra layer of protection" against chips.

  17. Weather the loco if you like, wrap it up, take it to the club, and begin to brag. This is the most important step, as very few people seem to realize that it takes more real effort to read this message than it does to get a good paint job on a brass model!
Above all, follow these simple rules:

Painting, brick red

21 Mar 94 01:00:00 GMT

What paint best matches red brick color?

Gee, I've been waiting to answer that question. I came upon the answer right after I started getting back into model rr, a few years back. Somewhere w-a-a-a-y-y back in my memory, which I believe I read when I was about 12, says that the popular color for bricks (at least prior to the last few years) was venetian red. And there is a color by that name. (I think it's Polly-S, not Floquil) And just to show how well it matches, I kitbashed a DPM bldg with some embossed & colored foam from, I think, Heiki, that was brick, and the color matched .


Painting, Diosol

21 Mar 94 01:00:00 GMT

I am soon to become a first-time user of Floquil paint. I realize that Diosol is the required solvent for thinning, but is Diosol required for cleaning brushes and airbrush, or can I use another solvent for the clean-up work?

Why would you want to use something else? If it's cost you're worried about, perhaps you're buying Diosol in those little tiny jars???? They also sell it in larger metal cans and it is MUCH MUCH cheaper that way. Hope this helps.

...

While the metal cans of Diosol are MUCH MUCH cheaper than buying the little tiny jars, it still doesn't beat laquer thinner's price.

Diosol and laquer thinner are similar in composition, but because they are not exactly alike, I suggest using only Diosol for thinning and leave the laquer thinner for cleanup.

...

I use mineral spirits for cleaning up after most of my Floquil paints. I have found that there are a few that just do not clean up well with the mineral spirits, so I keep a can of Diosol handy for these colors. I don't recall right off the top of my head which ones they are but when I use them I sure do know which ones they are. Most (90%) of my painting is done using Floquil paints with an air brush.

...

I would strongly suggest not getting laquer thinner anywhere near a plastic model. The one time that I did this (accidentally), the plastic instantly dissolved. ...

Courtesy of this newsgroup (I can't remember who suggested it, but thanks), I now use Lacquer Thinner for cleanup after painting with Floquil. It works just as well and is substantially cheaper even than the big cans of DioSol. I try to soak the narrow passages of my airbrush in the stuff for half an hour or so after using it for floquil (or testors, etc). I use Diosol for thinning, and for cleanup when brush painting (I keep a little jar for several sessions, until it's too dirty to use). B.T.W. I never bought one of those tiny bottles of diosol (I think 8 oz was my first size) and I still think it's too expensive to use for cleanup.

You can get lacquer thinner anywhere you get paint, varnish, etc.

I'm mostly converted over to AccuFlex now, but still use Floquil or Testors for drybrushing, metallics and a few other colors that are missing from Badger's new line. Among its other good properties, AccuFlex cleans up with water, which is so nice.


Weathering

21 Mar 94 01:00:00 GMT

Weathering, chalks

What tips can you give me when weathering with chalks?

About "fixing" the chalk in place. I use Testor's Dullcote in the small spray can. I have heard several people say that they tried different brands and settled on Dullcote -- I've never used anything else.

About chalks disappearing when sprayed: I use a paintbrush loaded with chalk and lightly drop the chalk onto the model where I want the weathering. Then I go back and rub it into the paint. Usually, it's stuck so well that it won't come off even if I wipe my finger over it. When I spray it with Dullcote, I make sure to spray a light coat -- just enough to seal the chalk. I have noticed that the weathering is minimized slightly, but it definitely doesn't disappear. My guess is that if you don't rub the chalks in, the aerosol spray blows the chalk off before the Dullcote can fix it to the model. I have noticed that dark colored box cars tend to swallow up the chalk (make it invisible) more than light colored cars. That's probably because of the smaller contrast between the car color and the chalk color.

By the way, the chalks I use are "Sanford" brand and I use the set called "Earth Tones". They are commonly available at art and craft stores and cost $5-$6 (in Boise anyway). Another set that I know people use is the set of gray shades.

...

Unless you're using very high pressure for spraying, it's unlikely that the chalk weathering is being blown off. But you are changing the reflective properties of the surface.

You need a rough surface to hold the chalk. You might try a light spray of dullcote, delivered from farther away than normal, so the spray is almost dry as it hits. You'll also want to apply a normal coat of dullcote after you're done, to seal in the chalk. Otherwise it'll rub off with handling. This final coat will also change the appearance of your weathering. The effect of chalk weathering is in large part due to the micro-roughness of the chalk itself. (This has nothing to do with the roughness of the surface previously mentioned. That was just to get the chalk to stick.) When you seal in the micro-roughness, even with a "flat" spray, you completely change the reflective nature of the surface, and a lot of the weathering effect disappears. This is very pronounced for light-colored weathering on dark cars, and much less so for dark weathering on light cars. When weathering boxcar red cars, I have to make them look garish, almost cartoonish, with lots of "extra" weathering so they look right after the seal coat.

Hint: eastern cars weather due to rain, soot and corrosion. Western cars due to sun bleaching and abrasion. Thus eastern cars tend to weather dark, and western cars light.

...

I have experimented, with some success, using ladies' cosmetic blushes which seem to be a caked powder. They come in a wide variety of colors [caution: some look somewhat metallic] and can be easily applied with the applicator supplied or a Q-tip. This method is great for moderate and subtle weathering.

If real heavy weathering is desired, I use weathering paints or lacquers.

The beauty of powders or chalks is the ease of removing what you have done if dissatisfied. However, the blushes, like most powders/chalks, can seem to disappear if too heavily oversprayed with a clear "fixative".

Weathering, dirt

Any thoughts on how to simulate 3-D clumps of mud and dirt in HO scale? I'm building the Walthers (Kibri, actually, I think) front end loader, and I've never seen any such construction equipment without very large clumps of dirt and mud on it, especially on the tires and scoop. Looking at the numbers, realistic dirt should be noticeable, so I'd like to simulate it.

Consider combinations of dry pastel (chalk-type) and paint. For example, scrape the pastel with a knife to get lumpy stuff, then drop it on wet paint.

... This is just a quick idea; I've never used this one on anything but scenery, but what about borrowing from the "bonded ballast" idea? If you were to thin down some white glue, then spray? eye-drop? it onto the equipment, then lightly sprinkle real dirt, let dry, maybe enough would adhere to fit your purposes. Of course, this method might well be too crude, but I have to put in the disclaimer that it's just off the top of my head!

...

I just started experimenting with chalks and I'm really impressed. I just bought an F7 A-B set and wanted to lightly weather them (that recently washed look). I used black and brown chalks on the roof and black, brown, and mustard colors on the sides (Union Pacific F7 with gray roof and yellow sides). What I really like about chalk is that it creates a subtle, road grime sort of look but has more variety and brings out details better than a wash or a light overspray of paint.

It seems like darker chalks work better on light-colored paint and medium or lighter-colored chalks for dark paint. If you look at prototype box cars, they all look about the same color -- lighter colors darken and dark colors lighten until they all have that medium-dark grime look.

I still use paints to touch up the fans and exhaust stacks, and to weather the trucks, fuel tank, etc.

...

The old "zip texturing" method makes excellent dirt, clumps and all.

Obtain some dry paint pigments at your favorite art store or find some commercial zip texture kits at a train store. It's a little expensive, but goes a long way. Get earth colors, of course.

Mix the paint pigment into some dry plaster - Hydrocal works very nicely for this. Use the pigment sparingly; it's easy to add more but kind of hard to get it out. Mix thoroughly.

Paint some water on the area to be made dirty and sift the plaster mix over it. The plaster will absorb water and bond with the surface yet will still maintain its fine texture. Put a little in a spoon, hold the spoon over the dirt area and tap the side of the spoon - little clumps will fall off the sppon. Maybe spritz a little water over the area and add some more. Repeat until you like the looks.

If you want to make a nice dirt road, mix up some "water putty" to a heavy cream consistency and gently pour it over the road area. It has enough surface tension to form a raised area, yet stays nice and smooth and flat. If you pre-wet the area, it will flow into smoother edges. Sift some of the plaster mix over it for color and texture. When it dries, lightly rub it with a Bright Boy to make smooth areas where it was worn by tires.

Sometimes the old ideas and techniques are worth trying...

Weathering, techniques

Any hints on wood weathering techniques?

I mostly use the Letraset felt pens. They come in a bunch of Pantone colors. The M series are wide and work great. I have the warm gray colors and most of the 40X, 41X, 42X,& 46X ones. My favorite one is 451. They dry fast so you can as you construct. They do smell like marker pens though. In the latest NG&SL Gazette someone aged his wood by toasting it. By pulling it out at different times you get board to board variation. Makes the wood brittle though. They also once had an article on the Letraset pen method but I don't remember the issue.

...

I use the same india ink and alcohol mixture to stain wood, and I accidentally found a good way to make water stains when using this mixture. I used some cyanocrylate (sp?) glue to attach some small parts to a water tank I was making and it unknowingly wicked into the wood. I didn't see this until I applied the ink and alcohol and it caused the area of glue to simulate a water stain.


Painting road ties

21 Mar 94 01:00:00 GMT

Is there an effective way to make Atlas' plastic ties look better? Has anyone tried painting them, and if so, how did it work? Would any of the Floquill colors be good for this purpose?

Almost any-ol' paint of the right color will do the job. My personal favorite is Floquil Roof Brown. It's dead-flat, goes quite far if thinned 50-50, and "just looks right to me". Just airbrush the rails and ties... the nickel-silver rails are worse to look at than the ties. Then clean it all off the railtops with a bright boy.

Why not Floquil "rail brown"?? IMHO it's way too light of a color... closer to mud than oily OLD rust.


Drill sizes

10 Jun 94 01:00:00 GMT

While there isn't an algorithm that works for drill size to diameter (at least not a simple one), there is a look-up table.

  Drill        Diameter     Drill        Diameter     Drill
       Diameter
   Size    (in.)      (mm)   Size    (in.)      (mm)   Size    (in.)
     (mm)

     1    0.2280     5.791    41    0.0960     2.438    81    0.0130     0.330
     2    0.2210     5.613    42    0.0935     2.375    82    0.0125     0.318
     3    0.2130     5.410    43    0.0890     2.261    83    0.0120     0.305
     4    0.2090     5.309    44    0.0860     2.184    84    0.0115     0.292
     5    0.2055     5.220    45    0.0820     2.083    85    0.0110     0.279
     6    0.2040     5.182    46    0.0810     2.057    86    0.0105     0.267
     7    0.2010     5.105    47    0.0785     1.994    87    0.0100     0.254
     8    0.1990     5.055    48    0.0760     1.930    88    0.0095     0.241
     9    0.1960     4.978    49    0.0730     1.854    89    0.0091     0.231
    10    0.1935     4.915    50    0.0700     1.778    90    0.0087     0.221

    11    0.1910     4.851    51    0.0670     1.702    91    0.0083     0.211
    12    0.1890     4.801    52    0.0635     1.613    92    0.0079     0.201
    13    0.1850     4.699    53    0.0595     1.511    93    0.0075     0.191
    14    0.1820     4.623    54    0.0550     1.397    94    0.0071     0.180
    15    0.1800     4.572    55    0.0520     1.321    95    0.0067     0.170
    16    0.1770     4.496    56    0.0465     1.181    96    0.0063     0.160
    17    0.1730     4.394    57    0.0430     1.092    97    0.0059     0.150
    18    0.1695     4.305    58    0.0420     1.067
    19    0.1660     4.216    59    0.0410     1.041
    20    0.1610     4.089    60    0.0400     1.016

    21    0.1590     4.039    61    0.0390     0.991
    22    0.1570     3.988    62    0.0380     0.965
    23    0.1540     3.912    63    0.0370     0.940
    24    0.1520     3.861    64    0.0360     0.914
    25    0.1495     3.797    65    0.0350     0.889
    26    0.1470     3.734    66    0.0330     0.838
    27    0.1440     3.658    67    0.0320     0.813
    28    0.1405     3.569    68    0.0310     0.787
    29    0.1360     3.454    69    0.0292     0.742
    30    0.1285     3.264    70    0.0280     0.711

    31    0.1200     3.048    71    0.0260     0.660
    32    0.1160     2.946    72    0.0250     0.635
    33    0.1130     2.870    73    0.0240     0.610
    34    0.1110     2.819    74    0.0225     0.571
    35    0.1100     2.794    75    0.0210     0.533
    36    0.1065     2.705    76    0.0200     0.508
    37    0.1040     2.642    77    0.0180     0.457
    38    0.1015     2.578    78    0.0160     0.406
    39    0.0995     2.527    79    0.0145     0.368
    40    0.0980     2.489    80    0.0135     0.343

Soldering, resistance

20 Mar 94 01:00:00 GMT

Any recommendations for a resistance soldering unit?

Go to your local friendly electronics supply house and buy a transformer with 110v primary, 6.2v (? or there about) secondary and a 4 to 6 amp output on the secondary.

Go to your local Radio Shack and get an insulated box big enough to hold the transformer.

Wire a 110v plug to the primary of the transformer. (Do I need to remind you to use a grounding plug and take care not to electrocute yourself???)

Run the secondary to two wires, one with something like an alligator clip, and the other to a clamp making a good connection to a carbon rod.

Where do you get a carbon rod? one might ask. Go somewhere where you can wash some chemicals away, and cut up an old flashlight battery or two. I have had good luck with both C cells and AA cells. The center contains a carbon rod. Make a point on the rod with some sandpaper, or a pencil sharpener, or something, and clamp the second wire from the transformer's secondary to it. Radio Shack will have conenctors that will do the job.

Now, when you plug in the transformer to the wall, and you connect the alligator clip to something metal connected to what you want to solder, and touch the sharp tip of the carbon rod to where you want to solder, the metal right around the tip of the carbon rod gets REALLY hot. Sounds kind of like one of those $250 dollar units to me. If you really make it fancy, you might spend $25 or $30 building the thing.

How to make it fancy??

  1. I like to put a control on the 110v side of the transformer. A normal light dimmer works well, although I have also had good luck with a sewing-machine foot control. These do not really have the current rating, but are ok for light duty work. I like having both hands to set up the work (the rod holds stuff in place) and then Zap with the foot.
  2. I use large stereo-type plugs to connect to the secondary side with the clips and rods. This lets me have several different rod-size and clip configurations that are easy to switch.
  3. Fancy handles for the carbon rods...
  4. whatever else comes to mind. For the price, and ease of construction, you can afford to experiment.