Introduction: Molds and Techniques for Colored Pencil Projects
I started working with colored pencils (CP) about a year ago. I bought a small lathe and wanted to turn interesting items other than the usual bowl. I have learned a few things that I want to pass on. This is more about the mistakes I have made and how I overcame the problems CP present than the final product. The first lesson is that CP is not like wood. It doesn't stay together when you apply power tools unless you plan ahead.
Cutting the CP: I tried a pruner, branch lopper, jig saw, chop saw, etc. I even tried a band saw with a vacuum attached to suck up the pieces and retrieve them later out of the vacuum. My goal is not to throw anything out. Use it all. Using CP in full length is preferred, but many times you want to make something smaller. I settled on a sharp pair of pruners and comfortable gloves. I take all the small pieces left over and put them into plastic water bottles and add resin or epoxy to make lamps (see below).
Resin vs epoxy vs glue: I first started by wrapping the CP with tape to make a mold and then adding fiberglass resin. Fiberglass or "surfboard" resin stinks but holds the CP together pretty well. On the lathe, it wears out your tools quickly and they can gouge deep cuts if you don't hold onto the tool firmly. Epoxy is a better but more expensive choice (eBay has a few brands for $60 and up. I would avoid the 1 minute or 5 minute epoxy. Better to take your time when casting with CP. More on materials later.
Go Big: I started pretty small. The lamps in the first photo came out so small I had to use candelabra bulbs and shades. The lamp socket is clearly visible, which I don't prefer. Better to see all base and shade. But don't go too big. The cost of epoxy and pencils really add up. When I was going crazy I was spending $90 per month just on carbide tips for my lathe tools. Luckily, I started trying to sell lamps at craft shows. Men normally follow behind the women at shows. If they are interested, they will come in and often give you woodworking tips. One gentleman taught me how to sharpen the carbide tips on a diamond hone from Harbor Freight. One woman invited me to speak to her turning club and we talked about turning for quite a while. I picked up a lot of good tips this way.
Molds made from tape and cardboard: Cardboard has it's place but plastic water bottles are a better way to start. Cardboard tends to leak at the bottom. Resin / epoxy don't expand that much but can get very hot (180 deg. F) and that will loosen the tape. The last three photos show a project that took over 10 hours to complete. The first 7 hours were spent cutting and gluing pieces to a file folder that I then curled to make a cylinder. I tried to cast it with fiberglass resin in a vacuum chamber. Not my cup of tea. You normally want all the bubbles out, but sometimes find a way to use the imperfections to add character and texture to a project. Using a jiggle table or pouring the resin from 3' or 4' above the form can help reduce the chance of bubbles. Water bottles are nice to use as a form because you can squeeze them as the resin is drying to reduce empty spots and help bubbles work their way to the surface. The only problem is stuff will float right out of the bottle after casting. Try stuffing foam rubber around the top to hold the pencils down. The vacuum chamber worked about as well as simply squeezing and pouring from well above the project. Letting the resin sit for a few minutes after mixing also helped bubbles come to the top.
Embracing mistakes: After spending about $1000 on CP over a few months, I started casting tree seeds (TS) I find on the street while walking my dog, Bob. Free materials. TS are a lot like CP, but the CP has a painted surface that doesn't hold together as well after casting. I tried rolling the CP between two sheets of 40 grit sand paper to roughen up the side of the pencil. That really helps especially when you are casting something like a religious object (photos below). I cast those (or cut them on a chop saw) pretty thin. You want space between each CP for resin / epoxy to get in between. You want to glue each CP down to a cardboard form or they will float away when you pour the resin. I hot melt glue everything in place before adding resin. The glue will show up on the side of a project that you are turning on the lathe (or sanding on a disc sander, for example) as a dark wet spot. Try to glue on the inner surface so you have only CP and resin/epoxy showing on the outside. Try using white hot glue sticks when you are casting with white resin (my favorite - I have tried a lot of colors of resin / epoxy and white works the best for some reason. It dries consistently and I can pour an entire project in one step as opposed to making multiple pours over several days while trying to avoid wet spots. When you cut a project with a wet spot on the chop saw it will make a mess - trust me.)
Embracing mistakes, continued: If you end up with voids on the side of a lamp, for example, try spraying the whole thing with spray paint, then turn or sand a 2nd time before polishing. The first white lamp shown is Norfolk Island (Star) pine leaves in Specialty Resins white epoxy from eBay. It's cheap and sets slowly. It was round but the heat from the epoxy twisted the form (water bottle) so much I ended up putting on the table saw (Makita I bought over 20 years ago - not a good idea to cut this stuff on your good tools). I then sprayed it black, sanded, polished and sprayed with clear acrylic before adding a base, drilling for lamp rod, etc. The second photo is Liquid Ambar, and the last one is crayons in fiberglass (surfboard) resin.
A bit about working with crayons: They melt so best to cast once, turn on the lathe removing the outer bottle and cutting into the resin/crayon surface until you like the colors. Forget the texture. You won't get it right until you cast it a second time. Center it in a larger plastic bottle and set in clear resin. Spray the inside of the bottle with mold release first. Use toothpicks stuck into the lamp to center it inside the bottle. You can see solid wood cores (closet rod) on all my projects. The wood core allows turning on the lathe, and later drilling for the lamp parts. And later for screws to go into from below (if you want to attach a wood base.)
Did I mention they melt? Casting a 2nd time should reduce the melting when you put it near a window, but some color does start to appear on the base over time.
A word about drilling for a lamp: I have tried many ways to get the lamp straight. I ended up holding the lamp between my feet and drilling from above with a long 3/8" bit. I let the drill "catch" every few seconds and loosen the grip with my feet, spinning the whole thing to a new position. Then I drill a little bit more. I start slowly and let the lamp turn a few full circles before drilling all the way through into a piece of scrap wood. If the lamp still comes out a bit crooked, after assembly just tweak the socket to one side with your hand until the bulb sits vertical. Sockets are made from cheap metal that bends easily. (See last page for photo.)
Mistakes: You can try to go back and fill all the little imperfections with CA glue, more epoxy or resin, etc. but it's time consuming. If you must, try moleskin or double sided foam tape. With the tape, take a hole punch and put the tape over the imperfection. Fill the punched hole with more epoxy and let it dry. The moleskin or tape will hold the epoxy well above the surface so when you turn it again, it will come out flat. The last two photos show the holes and pits that appear due to bubbles, and the moleskin in place ready to patch the hole with more epoxy. You can patch with CA glue but those spots may appear different after you polish the lamp.
Buy some small (5 to 10 oz.) squeeze bottles on eBay. Keep the 2 parts to epoxy handy for mixing small batches later. 5 minute epoxy in 10 oz. bottles is also a must have item. I pretty much glue every part of a lamp in place so it will hold up over time.
I just had to include the photos of the red pinnacle / spire / giant failure for you to see. This was supposed to be my "Life Work" or monument to my success. You can see where the tape / hot glue / cardboard failed at the bottom and 40$ worth of marine grade red epoxy from Polymer Composites went all over the yard. I still haven't finished this project. It's just too large and expensive to keep working on. It's make from Liquid Ambar seeds that I cut in half with a tree pruner then hot glue to a cardboard form with an Ad Tech 200 watt glue gun.
Glue guns will really burn you badly if you are not careful. I wear gloves. The glue gets so hot it burns well before you even feel it and start madly trying wipe hot glue all over your clothing to get it off. Why am I doing all of this again? Oh, yeah. It's getting out into the world and becoming a "maker" and meeting people and listening to them "oooh" and "ahhh" then walk away saying nicely that they don't really need a new lamp. Lucky I kept my day job.
More on molds: The whole point of this ible' is to talk about molds and fixing mistakes. But the last year has been so much fun and so interesting it's hard to stay on topic. Let me start with that first photo. I did 4 shows last year and got a few requests for the Star of David. I had the crosses on display and I guess people wanted fair representation of all religions. (I'm glad no Buddhists showed up - making that would be difficult.)
I gave this star away for the holidays. You can see in the later photos I used a stencil, spray paint, hot glue and my trusty pruner to set it up. You will do a lot of standing around at a craft fair so it's good to bring work along. People love to see work in progress. You can never use too much glue.
After cutting and gluing all the pieces in place, glue strips of cardboard along the sides - not too close - you want to have plenty of surfboard resin or epoxy to grind away. I use a 7" grinder clamped on the work bench with a 30 grit disc to get started shaping, then 40 grit on the belt / disc sander combo. Then orbital sanders to get it ready to polish. I use 150 - 3000 wet paper to get to the desired finish and often spray it with acrylic to seal. Then spray glue felt on the back as a final touch. (Try to find "professional" glues - they hold much better than standard types of glue.)
Cardboard Forms: The middle photo is a gift box from the 99 cent store. This is a pretty deep box that will hold most of a pencil. I glue a piece of 4x4 hardwood in the center first. I can screw a chuck into this and turn it on the lathe to make a globe lamp. Every pencil has to be glued individually. You need to leave space between each pencil, and preferrably rough up the pencils on 40 grit before casting and turning. You DO NOT want 20 pounds of epoxy and CP flying off the lathe into your face screen if the casting is too weak. Trust me on this one.
Safety: I learned a few things this past year. Probably the most important is to listen to yourself, learn your limits, drink alcohol after working and take it easy. There is no point in losing a finger just because you need to get more stuff ready to sell in a show. Get onto You Tube and look around at how other people are doing things.
For example, cutting crosses (first photo) on the chop saw is just a bad idea. I will not do it again. If you don't have the tools, ask a friend if you can trash her or his band saw blade cutting epoxy. Seriously, the band saw is much preferred to the chop saw. Things made from epoxy get pulled into the chop saw blade much more than wood does. Making small items on a chop saw that require you to get your hand closer than 4" near the blade is crazy any way you look at it.
I found it very helpful to research the number of accidents every year in the U.S. on table saws, for example, before I would go outside to work.
The third photo shows the result of about 3 hours worth of my time on a cross. These are very precious but fragile. They are very difficult to hold together when you are shaping and polishing. This is one place that the moleskin technique comes in really handy. Filling holes and pits with more resin is tricky because of the physics of how liquids like to pit when they are poured. The moleskin makes it easy to pour a taller repair over a hole and then simply sand back to flat after drying. If I were to make more crosses, I would want to 3-D print a form then fill with pencils and resin. That way I could leave lots of room around the sides of the pencils for strength and plenty of resin to grind away while shaping on the disc sander. I would have to get a band saw and find a blade that can cut resin / epoxy before going forward. I didn't sell any of these, btw. I gave a lot of them away, mostly to kids. The kids at the shows are so interested in CP that it's hard not to want to give them something.
Last few words on Molds / Forms: The last photo shows a cone shaped surfboard resin and Liquid Ambar seed lamp with led lights embedded into the material. I used a kids bugle from the 99 cent store as a form with rolled cardboard inside to make it hollow. I cast a small wood base that I will cut off later after it comes off the lathe. Then I can reach inside and get to the wires for the led's. If you don't stuff them well inside before turning, you will probably cut a wire on the lathe. After wiring, I glued another wood base inside the base to hold the lamp parts. One big problem with this set up is that resin flows just like water after pouring. I cut a hole into an old work bench to hold the bugle in place while pouring, and sealed the bottom of the bugle really well with glue, tape and lots more tape. The last thing you want is your wife finding dried resin on your dogs feet after they walk through dripping resin. Don't ask me...
Just a couple more fun photos: I know there is something I missed. I hope you enjoy looking at a few photos from 2017. I started this project in Feb. 2017 and learned that there is so much more to making art than simply gluing and turning. The whole marketing / presentation side of art is what I was not really prepared for. Even the application process to a craft show is time consuming and challenging.
The first photo is a lamp made from Magnolia tree seeds cut long ways then hot glued to a 4x4, then cast in a 99 cent store gift box (stacked up) and the cut on the table saw. Super easy and not too dangerous to make and it sold the first day of the Sawdust Festival in Laguna Beach. Clear epoxy that was left rough right off the saw.
If you can get a decent finish without polishing, you will save a lot of headaches. The last lamp I made was polished surfboard resin that I polished with car wax. I left the wax residue in place inside the cracks in the resin (I added a little too much hardener when casting.) I thought I was going to have to throw it away but it turned out to be one of the coolest lamps I have made yet.
The second photo is of me drilling the core for the lamp shaft while standing on scrap plywood.
Third photo: clock made from CP. Very difficult to carve out the back for the clock movement. Best to use a mechanics grinder or dremel tool.
Fourth photo is of lamps in progress. Solid wood cores turned on the lathe to the size you want from a 4x4 scrap construction lumber, then pencils glued in place with plenty of space between for epoxy to fill the void. (The green one in back is Star pine).
The final photo is of the author on the Nova midi lathe. What an incredible tool. Thanks for reading. Rick
We have a be nice policy.
Please be positive and constructive.