Replacing a Broken Ski Boot Part

A guy came to Nova Labs last week looking for help replacing  a broken part on his antique ski boots.  The boots were matched with his antique ski collection, so he couldn’t just buy new boots.

The part was thin and saddle-shaped.  I decided a squish mold would get the job done.

A squish mold is a type of two part mold.  It is optimized for casting thin parts exactly like this one. A squish mold also lets you make castings of a part with holes through it, without the part locking in the mold.

Like other two part molds, a squish mold starts with a clay bed.

But instead of partially burying your positive in the clay bed, you fill the hollow side with clay. Then you attach the clay filled positive to the clay bed.

Build a mold box around the clay bed. It doesn’t matter if the clay doesn’t completely cover the bottom of the box. In fact, leaving a border free of clay makes the mold easier to use.

For this I used Smooth-on’s Sorta-Clear 37 mold rubber. It took several trial kits. I didn’t order enough, so I had to top the mold off with some left-over Dragon Skin 10.  The orange dot is a bit of Rebound 25.  I used it for the second half of the mold.  I did a little test pour to make sure it would cure properly.

The next day, I flipped the mold over…

and pulled the clay out.  This is now the bottom half of the mold.

I sprayed the bottom half with two coats of Mann Ease Release 200  and let it dry for 30 minutes.  Then I poured the cavity full of the Rebound 25. The Ease Release prevents the newly poured rubber from bounding to the bottom half of the mold.  Even with the Ease Release though, it took some serious pulling to get the two halves apart.  The positive popped right out.

The orange Rebound is the top half of the mold.

To cast in a squish mold, mix your resin and pour it into the lower half of the mold. Then “squish” the top half down into the the lower half.  The top half will displace the liquid resin, causing it to fill the cavity.  I put a heavy block of wood I had lying around to press the top half of the mold firmly into the bottom half.

Here’s a copy using Smooth-Cast 57D ready for demolding. Notice the thin flashing where the resin was squeezed up and out of the mold. That was easy to clean up. I could tear most of it off by hand. There were a couple of places I cut off with a razor knife.

Here’s the finished part next to the original.  I’m going to try a couple of other resins I have on hand to try to get a closer match on the color.

Here’s the new piece mounted in the boots.  My “client” says the fit is perfect.

Making a Two Part Silicone Mold

I’m teaching a class on Mold Making and Plastic Casting at NovaLabs in Reston.  Yesterday, I made a simple two part mold using something I designed in Fusion 360 and 3D printed as the model.

Here’s how it’s done.

Clay Bed

Start by rolling out a clay bed big enough to hold your model plus 1/4″ to 1/2″ of additional space.  If you’re using platinum cure silicone for the mold, make sure your clay is sulfur free.

We’re building the mold upside-down, so the clay bed will become the top of the mold. Make sure the bed is thick enough to yield a sturdy top mold half.

Seat Your Model

Place your model on the clay bed. In this case, the model is fairly simple and has a flat bottom.  I just pressed the model into the clay to ensure a tight seal around the bottom.

If your model is more complicated, you might have  to lay it on its side and build the clay around it.

Build Up the Clay

Add clay around the model. How much clay didn’t matter much in this case.  I just needed enough to hold the model firmly and to make the registration keys (see below).

If you’re making your mold with your model on its side, you would typically add clay up to the halfway point.  Depending on your model, it might be easier to start with a thick clay bed and hollow out a cavity for your model.

Smooth the Clay and Seal the Model

Carefully smooth the top of the clay bed. I start with a craft stick to level out the major lumps, then use my finger to cover any cracks and smooth the surface.

Make sure the clay is sealed up against the model. You don’t want silicone running down a crack between the clay and the model.

Make Your Mold Box

Here, I’m using a simple ring of stiff plastic I hot glued together.  This is an easy technique which works well for vertically molded, roughly cylindrical models. You can just wrap it around your clay bed and seal it tight.

For non-cylindrical models, you can make a box out of foam core and hot glue. You can either build it around the clay bed or start with the clay bed in the box. Whichever will be easier.

Make Registration Keys

Registration keys help you line up the two halves of the mold, ensuring a tight fit and minimizing flashing. You make them by either creating holes in the clay bed or sticking small objects, like marbles or acorn nuts, into it.  When you pour the silicone for the bottom half of the mold, it fills the holes or flows around the objects, creating the male or female half of the key depending on which technique you used. When you flip the mold over to pour the top half, that silicone will make exact negatives of the bottom half features, completing the keys.

Notice that I arranged the keys asymmetrically, with two keys much closer to each other. Since the mold is circular, this will make it easier to line the keys up. If I’d spaced them evenly around the perimeter, it would have to confusing when reassembling the mold.

Here I’m using the end of a hex bolt to put holes in the clay bed. I didn’t like the results. It distorted my carefully prepared clay bed and the keys came out sloppy.

Next time, I’ll use acorn nuts. I think they’ll give me sharper registration keys and keep the bed level at the same time.

Pour the Silicone

Mix parts A and B of your silicone rubber, as usual, and pour into the mold box.  Pour it in a thin stream, into the lowest part of the mold box. Let the silicone ooze around, up and over the model. This will help ensure air bubbles don’t get caught in any undercuts.

Make sure the top of the mold is thick enough to withstand the number of castings you want to make with this mold. A thin mold will tear or wear out more quickly.

Remove the Clay Bed

Once the silicone is fully cured, flip the mold over. This is now the bottom half of the mold.

Remove the clay bed.  It will be hard to get started. You’ll have to dig in with a spoon or your finger to pull out a piece of clay so you can peel the rest away. Once you get it started though, the clay should easily come out cleanly, in large pieces.

Clean out any residual clay using a toothpick or brush.

Make Pour and Air Escape Channels

Using your clay, make two pipes; one for pouring the resin, the other for letting air escape the mold.  I could have just 3D printed the channels as part of the rest of the positive.  That would have been easier.

Note, here I’ve taken the plastic ring off the mold.  That was a mistake. It was a pain to get it back on tightly enough the second pour of silicone won’t leak out.

Apply Mold Release

Since you’re pouring silicone onto silicone, you have to use mold release. Otherwise, you won’t get a two part mold. You’ll just get a single block of silicone with your model trapped inside.

Mann Ease Release 200 is a reliable product. Apply a light coating, making sure you cover the entire surface of the mold.  I usual spray it outside because it leaves a distinct petroleum smell I don’t like in the house.

This is a very fine aerosol. It won’t look like there’s anything on the mold. Resist the urge to apply a heavier coat.

Using a soft brush, lightly brush the surface of the mold. This breaks up any droplets and ensures complete coverage.

Give the mold a second light coat.  Allow to dry for 30 minutes.

Pour the Top Half of the Mold

Mix the silicone parts A and B and pour the top half of the mold. Fill the mold box just to the top of the pour and air channels.

Remove the Model

 Remove the mold box . The two halves will be firmly stuck together. This is because they are exact negative copies of each other. They fit together as tightly as anything can fit together.

Don’t worry. If you applied the mold release correctly you can get them apart by finding the seam between the halves and pushing on it with your fingernail.  Once you get a small separation between the halves, they should peel apart.

Remove the model and any remaining clay.

Cast Your Part

Reassemble the mold halves. Mix parts A and B of your resin and pour.

Demold Your Part

It should be much easier to separate the mold halves this time.  Pull them apart and remove your part.

I used some Smooth-Cast 325 I for this pour.  It was old and there was too much part A so I just wanted to use it up. I tinted it with So-Strong red. It didn’t come out great.  It’s taking forever to cure and the surface finish is poor.

Finish Your Part

Cut off the pour and air channels.  Depending on what resin you used, you can sand down the cut marks to get a smooth finish.  Hard urethane resins sand well. Softer urethane and epoxy not so much.

That’s it. You’re now ready to cast dozens or hundreds of your part.

Crepes on the Baking Steel

Crepes stuffed with cheese and strawberry jam are the traditional Sunday breakfast at my house.  I started making crepes after my daughter tried them for the first time while we were on vacation in Maine.  She was only three at the time, so when she told me Daddy should learn to make these, of course I had to.

I used to use a non-stick crepe pan. Those are almost fool-proof.  Just pour in a little batter, swirl it around the pan and flip.

The one draw back is you can only make crepes as large as your pan. Mine was 6 inches, which was fine for breakfast sized crepes but not for big dinner crepes stuffed with savory meat and veggies. To make those big boys, you need a flat top griddle and a crepe spreader like they use in creperies. You also need a little practice spreading the batter thin and flipping them.

For the flat top I use a Baking Steel griddle.

This easily handles crepes up to 12 inches. It’s also an excellent multi-tasker. Its griddle side is great for pancakes, English muffins, potatoes, steaks, pretty much anything. Flip it over and you got a baking surface better than any stone. I make baguettes, boules and ciabattas every week and always get fantastic results.

 

A Note on the Gear

There are two kinds of crepe spreaders, the good kind and the bad kind. Don’t get the bad kind.

The good kind is simply two round dowel rods joined into a T. You put about 1/4 cup of batter on the griddle and put the thicker rod in the middle of the batter. Then you use the thinner handle to spread the batter into a thin round crepe. The spreader floats on the batter so you don’t have to worry about controlling the thickness of the crepe. Just work fast and keep twirling.

The bad kind has a flat blade with sharp corners. The corners tend to tear the crepe as it begins to set up.

In addition to the griddle and spreader, you’ll need a thin, offset spatula. A bench knife or  dough scraper is also handy for clean up.

Recipe

The basic crepe batter is similar to a thin pancake batter but without any leavening agents. It’s suitable for savory and dessert crepes. There are dozens of variations, including herbed crepe batters, cornmeal, rye flour and others.

2 eggs
1 cup milk
1/4 cup water
1 cup all purpose flour
1/4 tsp salt
2 TBS melted butter
1 TBS solid butter for the griddle

Mix all ingredients in a food processor or blender. Refrigerate at least 1 hour to allow bubbles to dissipate and flour to absorb the liquid.  Overnight is better but not necessary.

After resting, the batter should be a bit thicker than heavy cream.

Heat the griddle over medium to medium high for 10 to 15 minutes. This is the trickiest part. The griddle should be hot enough the a few drops of water thrown onto it immediately boil but not so hot that they “dance” on the griddle. You’ll have to experiment with your stove top to get the right temperature.

Rub the griddle with butter. The butter should sizzle but not brown or smoke.

Using a ladle or measuring cup, pour batter into the center of the griddle.  An 1/8 cup makes roughly a 6 inch crepe. A scant 1/4 cup will yield a 10 to 12 inch crepe.

Next, use your spreader to distribute the batter into a thin circle. It will take several passes to fill any holes and get a nice round shape. Getting the twirl right will take a little practice, but it’s not hard.

The crepe should be ready to flip in roughly 1 minute. Watch the edge. When it gets crisp and starts to curl, slide your spatula under the crepe and make sure it hasn’t stuck anywhere. Then flip the crepe and cook the other side for another 45 seconds to a minute.

For our breakfast crepes, I fill them with mascarpone or just cottage cheese and jam, then roll them up and sprinkle with powdered sugar.

Use the last bit of batter to make a little crepe for your dog. He’ll appreciate it.

 

Another Fantastic Joint (Hometown edition)

What do you say about a restaurant with over 180 whiskeys and a small, thoughtful menu build around their industrial-strength, wood-fired rotisserie?  What if they have a very friendly, extremely knowledgeable staff that loves to talk about their food?  What if the beverage manager will pour you a custom flight of Bourbons so you can sample several, without having four shots for lunch?

What if you drive past this joint every day on your way home from work?

That was me yesterday at Brine in the Mosaic district of Fairfax county.

I was roaming around Google Maps looking for somewhere new. I clicked on them because they’re close to home. When I visited their web site, I was intrigued. The whiskey list alone goes on from 14 screens.

I got there during the slow time long after the lunch rush and before Happy Hour.  The place was basically empty except for a large table in the back. That was fortunate because it gave me a chance to talk with Timothy, the new beverage manager, and Tracy, a bartender. Tracy is also a classically trained chef. He offered many insights into Brine’s approach to food and their menu.

As I said above, the menu is small and very thoughtful. There are roughly 30 items, including appetizers, soups, salads, entrees and desserts. They have a couple of typical bar foods, like a burger (everyone has to have a burger) and smoked pork. But most of the items are on the funky and creative side.  Like the Lamb and Cheese sandwich I got or the Lambs and Clams broth on the soup menu.  Or the sea bream salad, a “simple fish” menu and English Pea Crostini.

While I didn’t get to try anything from the rotisserie yesterday, just looking at the thing makes me want to go back.

The dinner menu includes daily fish and meat specials from the rotisserie.  They warn you that it takes up to 30 minutes to prepare one of those dishes.

That’s probably what the 180 whiskeys are for.

Speaking of the whiskeys, Timothy says the old beverage manager may have gone a bit “overboard” on the selection.  He’s trying to trim it down to a “respectable” 100. I tend to agree with him.  They carry both the Catocin Creek 40% and 46% bottles.  I have a hard time imagining some one tasting whiskeys saying, “The 40% was good. Now I’ll try the 46% instead of one of the other 180 varieties.”

Timothy and I debated whether a corn whiskey can be called a Bourbon if it doesn’t at least pass through Kentucky.  He said yes. I say no.  He also told me about some new flights he’s curating. He said was going home that evening to work on those.

The space is large and open, with lots of hard surfaces.  I worried that it might get loud in there a dinner. Tracy pointed out the sound baffles hanging from the ceiling. He claims it not bad during the week but admitted that Friday and Saturday night get raucous.

I might have to set aside a weekend night soon to find out.

Highly recommended if you’re in the area.

 

Another Exceptional Joint

When I travel, I seek out exceptional, local joints.  I’ve found some real gems this way (like this Cincinnati joint, sadly now closed).

On a recent trip north of Philly, I had an evening free so I made a bee-line to the Geechee Girl Rice Cafe in Mt. Airy, PA.

I’d been wanting to go here ever since I saw it on Triple D.  I recreated Chef Erwin’s signature North African Chicken dish.  My version is really good, but I wanted to try the real thing.

I got there early on a Friday evening.  The place was almost empty. Just one other table had customers.  The staff was really nice and very attentive. I guess that was easy, since there were only three of us in the restaurant.

I told the hostess why I had come. About 10 minutes later, Chef Erwin came over and introduced herself.  We talked for about 5 minutes about her business, the neighborhood and her food.  She stopped by several more times while I dined.

I started with soup of the day. It was a white bean and smoked red pepper.  Like most of the food here, it was a simple dish.  Much more comfort food than haute cuisine.  The base of the soup was a clear broth. Chef Erwin added celery, beans, smoked peppers and herbs to make a light, flavorful starter.

After that I had Chef Erwin’s version of the North African Chicken.  It was everything I’d hoped it would be.  I’m happy to report that my version is very close.  Mine’s good. Chef Erwin’s was better.

I think the biggest difference between the two dishes is that Chef Erwin uses a much smaller bird than I had been using.  Her’s are about 3 lbs.  I’d been using the 5 to 6 lb monsters you get at Safe way.  Her’s have better flavor and, because they cook more quickly and evenly, are moister through.

Next time I make this, I’m getting a better quality bird.

I don’t usually get dessert, but I don’t know if or when I’ll ever be back.  So I loosened my belt a notch and asked to the the dessert menu.  There’s the typical brownie sundae and rice pudding and pecan pie.  I homed in on the Gingerbread.

Good choice.  It was excellent.  Light and tender with a warm, almost pudding like center.  Topped with whip cream it was a great way to end the meal.

I said goodbye to Chef Erwin and headed home, happy I’d made the trip.

Cuban Sandwich

I’m doing more cooking than writing these days.  I’m still breaking in the new kitchen and having a lot of fun doing it.  That’s eating (Ha, ha.  See what I did there) into my writing time, so I’ve got a backlog of posts to make.

While I get caught up, here’s a little something I whipped up yesterday.

It’s a homemade Cuban Sandwich which is pretty much as homemade as you can get.

I  made the ham (substitute a meatier cut for pork belly). I made the roast pork. I made the pickles. I blended the mustard. I made the Cuban bread (I used my homemade sourdough starter instead of the polish this recipe calls for). I even rendered the lard that went into the Cuban bread.

The only thing I didn’t make from scratch was the Swiss cheese.

So when I say I whipped it up yesterday, I actually mean it’s been three weeks from the start of the project (curing the ham) to the finished product.

Dry Ice, Ice Baby

Here’s a preview of something I’ve been working on.  Hope to have it ready to post by next weekend.

I’m back!

After ten weeks of no kitchen, I’m finally back.  They finished the major work on the new kitchen the middle of last week.  I was able to make some simple things, like scrambled eggs and vegetable tacos Thursday and Friday. But I didn’t have time during the week to unpack everything, so I couldn’t really give the new space a real work-out.

This weekend, I got enough unpacked that I could give it a test run. I decided to start with a loaf of rustic bread, using the home grown levain I started at the beginning of the remodel.  There was some yelling and frustration (“Where’s my bench knife?” “Where’s my scale?”) and it’s going to take some getting used to the new layout, but overall I’m very happy.

I started with a bunch of new toys.

 

 

From left to right I’ve got a couche for shaping and proofing baguettes, two wicker bowls for proofing boules, my home grown levain (I named it Laverne, BTW), a golf towel and/or kitchen towel that came with my new sink, two New England Style Hot Dog Bun pans and a new digital scale that displays both English and metric units.

I cashed in my Amazon points while I was waiting for the remodel to finish. 🙂

Here the first loaf baking.  The lower oven door was damaged during installation, so I’m waiting for a replacement.

And here’s the inside.

I’m very happy with the color and crumb of the loaf.  It’s a nice looking loaf

The flavor was also spot on.  Laverne give it a nice sour tang. Not as sour as a true San Francisco sour dough. Just a nice background note. I’m looking forward to baking a lot more bread and pizzas with this starter.

The crust wasn’t up to standards, though. I had the hydration too high for this oven, so the loaf still had quite a bit of free moisture in it when the crust was done. That extra moisture made the crust soft as soon as the loaf started to cool.

I’ll adjust the hydration down next time.

When Amounts Count, Use a Scale

I’ve been baking with a scale for quite a while.  Weighing fluffy ingredients, like flour, is much more precise than using volume measures like cups and teaspoons.

Even if you carefully sift the flour and level your measuring cups, you can still be off by five to ten percent too high or too low.  That can mean the difference between a perfect loaf and a too dense loaf.

When you weigh your ingredients, you get exactly the right amount every time.  Whether you’re using English or metric units, weighed flour is the exact same amount every time. If you weigh out 400 grams, it’s 400 grams. If you weigh out 14 oz., it’s 14 oz.

My previous kitchen scale only displayed English units, ounces and pounds. My new one also displays metric units.

That’s going to make it easier to scale recipes up and down.  Imagine trying to triple a recipe that calls for 1 3/4 cup of flour.

1 cup x 3 is 3 cups.

3/4 cup x 3 is 9/4 cups. 9/4 cups is 2 1/4 cups. Plus 3 cups is 5 1/4 cups.

What a pain!

Even working in ounces, it’s difficult because my old scale displayed 17 ounces as 1 pound, 1 ounce.  So it’s 14 oz x 3 is 42 oz. 42 oz divided by 16 is 2 lb 10 oz. Again, what a pain.

In grams though, it’s just 400 grams x 3 equals 1200 grams.

Simple, easy. Math I can do in my head.

Recipe – Makes two loafs

100 g levain or sour dough starter. Can substitute 2 tsp of dry yeast.

420 g water

590 g all purpose flour

10 g whole wheat flour

13 g kosher or sea salt

270 g water, divided for humidifying oven

Olive oil

Mix levain and 420 g water in bowl of stand mixer. Using paddle attachment, mix for 1 minute on low to combine.

Add flour, whole wheat flour and salt to mixer bowl. Using paddle attachment, mix on low for two minutes.  Switch to dough hook and mix on medium low for five to seven minute.  Dough will still be wet, but should start forming ball on the hook and begin pulling away from sides of bowl.

Let stand, covered, for ten to fifteen minutes.

Spread a small amount of olive oil on work surface and spread to cover an 18″x18″ square.  Oil your hands.

Place dough in middle of oiled area and give one light stretch and fold.  Cover and allow to rest fifteen minutes.

Repeat three times for a total of four stretch and folds.

At this point, the dough should be smooth, elastic and tacky.  It should stick to the work surface and your fingers, but pull away cleanly.

Place in a lightly greased container, cover and refrigerate over night.

Place a baking stone on the middle rack of oven and a cookie sheet with raised rim on the lower rack. Pre-heat oven to 475° F.

Turn dough onto a lightly floured work surface. Divide in half.

Being careful not to de-gas the dough, form each half into a tight ball.  Place into lightly floured bowls and cover with a couche or clean kitchen towel.

Let rise until almost doubled. About one hour.

Place a piece of parchment paper on a pizza peel or back of a cookie sheet. Lightly oil.

Turn one bowl of dough onto parchment.  Score top with a lame, razor or sharp knife.

Bring 135 g (about 2/3 a cup) of water to a boil.

Slide the dough onto the baking stone.

Working quickly, cover glass of oven door with kitchen towels to protect from splashing water. Pull cookie sheet out just enough to expose a place to pour the water onto it and pour boiling water onto sheet.  Be very careful not to splash boiling water onto yourself or the oven door.

Close oven door and bake for twelve to fifteen minutes, until crust is dark, golden and crisp.

No more food porn

At least for a few weeks.  Thursday a bunch of guys came to my house and tore out my kitchen.  It’s down to the studs now.  The remodeling will take 4 to 6 weeks.

 

I’ve said before that my house and I are both in our early 50s and we both need work.  The kitchen had become critical.  Some of the cabinets were start to literally fall apart and one oven gave up the ghost a couple of months ago.

I’d planned on cooking on my Big Green Egg and I probably will.  But first I have to solve two problems.  Every horizontal surface in my house is currently stacked with boxes.  I have no room to prepare anything.

 

The other problem is where am I going to wash the dishes?  I don’t want to wash my dishes in the bath tub and all my bathroom sinks are too small to scrub pans.

I’ll probably have to get a couple of tubs and do it campground style.

Oh well.  In 6 weeks, I’m going to be making some amazing food.

Black Bean Burgers on Brioche Buns

When I published my Pretzel Bun recipe back in March, I, of course, used them to serve spectacular cheeseburgers.  A friend of mine who was once a vegetarian and sometimes still leans toward legless food challenged me to come up with a veggie patty to fill those gorgeous buns.

I failed. I could never come up with a veggie patty that could stand up to that substantial bun.

Eventually I fell back to a Brioche Bun and these excellent Black Bean Burgers from my new favorite food blog.  My friend said this meets the spirit of the challenge.

While I am partial to meat, I do enjoy the occasional vegetarian dish.  When eating vegetarian though, there is one thing I can not stand.  Dishes that pretend to be meat.  If I want something that tastes, “Just like a hamburger”, I’ll eat a freakin’ hamburger.  Don’t try to disguise tofu as steak or pass some paste made out of ground chickpea flour off as meat.

These black bean patties don’t commit that sin.  They are proudly veggie, but with lots of flavor, great texture and nice smokey, spicy kick.

I didn’t deviate from Serious Eats recipe, so you can just go there for the how-to.

Make sure you don’t dry out the beans too much during the roasting step.  You need enough moisture to hold the patties together during shaping and cooking.

Kenji said 20 minutes in the recipe.  That was too long for my oven.  After about 15 minutes the beans were split open and starting to get too dry.  I suggest checking them after 10 minutes and erring on the side of too moist.

I cooked mine on my griddle.  I was afraid if I tried to grill them on the Egg, they would fall apart.  My daughter wants them again, so I might try grilling them next time.

A Note on Shredded Lettuce

I’m not a big fan of ice burg lettuce.  It’s flavorless. It has little to no texture. As a base for a salad there are a dozen better options.  In general, I leave it at the store.

But there is one decent use for ice burg.  Shredded, as a base for a burger.

Shredding lettuce transforms it into a crunchy bed that adds a textural surprise to a burger. It also keeps a juicy, condiment laden burger from soaking through the bottom bun.

Just take a thin wedge of lettuce and slice about 1/8″ to 1/4″ thick.  Put a generous layer on the bottom bun and build the rest of the burger on top of that.