Ceramic Heater Core - Instructions

Rick Pollack

Here are the suggested assembly instructions. But since you are a maker, a creator, a creative force in the universe, feel free to disregard and do it your way (just be prepared to order some extra brass cores and nichrome :) Your kit includes the following items: 2x Brass core threaded M6 2x Nichrome wire (300mm each) -Ceramic adhesive w/brush and popsicle stick -Hook-up wires -Crimp connector pins (male and female) -M6 screw (drying stand and holder for heating) <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_kit.jpg?1262881442' alt='' /> Step 1: <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_step_1.jpg?1262881442' alt='' /> You’ll need the ceramic adhesive, stirring stick, brush, nichrome, and brass core. Stir the adhesive slowly (don’t whip air into it) but thoroughly. A little bit of thinner (water) was added to get a smooth consistency. Place one end of the nichrome in the slot located on one end of the brass core. The calipers in the following photos are set at 25mm for reference. For all of the talk about 6 ohms of nichrome for the heater, all that really matters is that you are in the ball park (5.5 – 6.5 or so ohms works fine – the only difference is that it will heat a little faster or slower depending on the length.) The included nichrome is 300mm in length with the expectation that about 250mm will actually get used for the core. You are welcome to carefully measure 6 ohms but it is unnecessary. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_step_1a.jpg?1263240664' alt='' /> Step 2: <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_step_2.jpg?1263241236' alt='' /> With one end of the nichrome in the slot, carefully wrap the nichrome around the core following the thread. You should have one loop around the slotted end – before the thread – and then follow the thread down. Once you’ve reached the end of the threads – add two more loops around the end. Though it is not critical, for best results, try not to have the nichrome overlap. You want the nichrome to have good contact with the brass. Check to make sure the nichrome is in the threads (not crossing over threads, the ridges are sharp and can fray the insulation. With the nichrome pulled taught, you should have about 25mm of extra nichrome on each end. It may take a couple of attempts to get it right. Just take your time and get an extra set of hands if you have trouble getting and keeping it wrapped. Once it is wrapped, bring the ends of the nichrome together and twist a couple of times. This will keep it in place while you add the ceramic and the ceramic cures. It is not critical that the two ends be exactly positioned. After you put the ceramic adhesive on and let it cure for an hour (or so) you will be able to free the ends and place them where you want them. So, at this point, just get it wrapped with the ends lightly twisted together. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_step_2a.jpg?1263241765' alt='' /> Step 3: <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_step_3.jpg?1263242402' alt='' /> Now that your core is wrapped it is time to add the ceramic. You can apply the ceramic using either the stick or brush. I’m using the stick. Dip the tip of the stick or brush into the ceramic adhesive. Slowly spread the ceramic over the nichrome. Spread a thin layer over the nichrome so that all of the nichrome is just covered. Try and keep the ceramic out of the inner threads but don’t panic if you get some inside as it is easy to clean up – even after it dries at room temperature. If the ceramic makes sharp points when you pull your brush away add a few drops of water to thin the mixture. Step 4: <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_step_4.jpg?1263244410' alt='' /> Let it cure for about an hour at room temperature. We just need it to cure enough so that when you unwrap the ends it does not come apart. (Note: If you are in a hurry, you don’t have to wait, you can proceed to the heating process immediately – it is just a bit more of a challenge.) Step 5: Warm up your soldering iron. We are going to solder the male pin to one end of the short hook-up wire and the nichrome to the other end. One end of the long hook-up wire will be soldered to the female crimp pin. However, before we do that we need to remove the crimp portion of the male pin from the pin itself as the crimp is going to used as the connector between the nichrome to the hook-up wire. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/male_crimp_pins.jpg?1263246071' alt='' /> <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/short_hook-up_wire.jpg?1263246578' alt='' /> Go ahead and lightly crimp the broken-off crimp on to one end of the short hook-up wire. You want to leave enough room so that and end of the nichrome can slide in before soldering it. When you slide the other end of the short hook-up wire in to the crimp pin, it should slide down into the pin itself. Go ahead and solder the pin onto the wire (be careful not to lose the crimp on the other end as it can easily fall off). You’ll need to repeat this process for all four of your short hook-up wires. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/female_crimps.jpg?1263311682' alt='' /> Attach the female crimp pin to one end of the long hook-up wire. Don’t place more than about 5mm of bare wire into the connector or the pin will not be able to slide all the way in. The connection between the male and female pins is very tight. You may need to use a small screwdriver to loosen up the female end if it is too tight. Step 6: After sitting for an hour, the ceramic should be pretty smooth (maybe a few bumps) and firm. Carefully untwist the wires and align them so that they are both on the same end of the core and about 5mm apart. (having the leads aligned along one end of the core simplifies the placement insulation over the core when the core is mounted on your heater barrel.) You may need to touch-up the ceramic after moving the nichrome around. (To avoid getting the wet ceramic all over the place, you should probably continue to get your heater core mounted and wired up for the initial heating, then touch it up before applying power.) You’ll need about 5mm of exposed (insulator-less) nichrome. If you have a vise place the core in the vise and position the nichrome end into the connector on the short hook-up wire. Solder it all together. Once it is soldered the nichrome should hold firm. If it is loose, try soldering it again. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_cure_1.jpg?1263246589' alt='' /> <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_nichrome_lead.jpg?1263264638' alt='' /> You can see that I pulled off a chunk of ceramic after I untwisted the wires and was positioning them. First I’ll finish attaching the hook-up wires, get it all set up for heating, touch up the ceramic, then heat it up. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_nichrome_leads_attached.jpg?1263311397' alt='' /> Now all of your wires should be soldered and you should be able to connect your crimp pins. Place an M6 screw into the brass core and place it in your metal “helping hands” or some other device that can handle 150C – 200C. We are going to heat up the core to quickly cure it. Notice there is ceramic on the exposed metal connectors to provide some electrical insulation. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_in_clip.jpg?1263311741' alt='' /> Before heating If you are using ReplicatorG and a MakerBot extruder controller with v1.6 firmware: Once your core is firmly mounted and the wires are connected, connect the long hook-up wire to your extruder controller. In RepG control panel set your temp to 50C. The measured temp will show 0 since no thermistor is attached (if you have a thermistor available, feel free to use it). The core should begin heating up. Use a temp probe or place your hand a few centimeters away to confirm it is heating. If it is not heating, double check your wiring and connections to the extruder controller. Let it heat for 20-30 seconds, this will get it to about 75C. Then, set the temp in your extruder controller to 0 (zero). Your controller should go into a slow heat mode where the core will heat very slowly. Let it heat for three to five minutes. Somewhere along the way your heater core should steam for several seconds. After the heating period shutdown your extruder controller (turn off power) and let the heater core cool. If there are any problems with the ceramic – a crack, you missed a spot or you just want to add more, go ahead and add it then repeat the slow heating cycle. (Note: in RepG, after setting the temp you need to click in another field for the temp change to register. I usually click on the PWM field after changing the temp.) For other configurations the objective is to slowly heat your core up to about 150C and let it sit at that temperature for several minutes. This process gets most of the liquid out (in the form of steam) and hardens the ceramic. Once the steam is out then you can wire up your extruder and get started. I usually let a heater core sit at extrusion temp for 10-15 minutes before using it for the first time. Be aware that the first you heat your core to your operating temperature, it may let off more steam for several seconds. Keep your extra ceramic sealed nice and tight in case you need to do a repair in the future. Step 7: <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_after_initial_heating.jpg?1263311990' alt='' /> After heating If there is any ceramic on either end of the core, you may want to scrape that off if you need good thermal contact. Mount and start using your heater. Screw the heater into position on your heater barrel. Add your nozzle, insulator, thermistor, insulation and other items and then power it up. Depending on how long you heated it, the core is somewhere between gray and gray-white. As you use it, the ceramic may get whiter – this is normal. Your heater core may heat at a slower rate than a wrapped barrel. Depending on your configuration it may take a several seconds for your thermistor to indicate that it is heating and it may take 2-3 minutes to get up to operating temperature. Good Luck!! Please send your comments, suggestions, questions, etc., to feedback@makergear.com

2010-01-11T15:08:54-05:00

ceramic-heater-core-instructions 3737962

2010-01-12T12:02:33-05:00

307372

Ceramic Heater Core - Instructions 2010-01-19T11:19:32-05:00 Here are the suggested assembly instructions. But since you are a maker, a creator, a creative force in the universe, feel free to disregard and do it your way (just be prepared to order some extra brass cores and nichrome :) Your kit includes the following items: 2x Brass core threaded M6 2x Nichrome wire (300mm each) -Ceramic adhesive w/brush and popsicle stick -Hook-up wires -Crimp connector pins (male and female) -M6 screw (drying stand and holder for heating) <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_kit.jpg?1262881442' alt='' /> *Step 1:* <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_step_1.jpg?1262881442' alt='' /> You'll need the ceramic adhesive, stirring stick, brush, nichrome, and brass core. Stir the adhesive slowly (don't whip air into it) but thoroughly. A little bit of thinner (water) was added to get a smooth consistency. Place one end of the nichrome in the slot located on one end of the brass core. The calipers in the following photos are set at 25mm for reference. For all of the talk about 6 ohms of nichrome for the heater, all that really matters is that you are in the ball park (5.5 - 6.5 or so ohms works fine - the only difference is that it will heat a little faster or slower depending on the length.) The included nichrome is 300mm in length with the expectation that about 250mm will actually get used for the core. You are welcome to carefully measure 6 ohms but it is unnecessary. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_step_1a.jpg?1263240664' alt='' /> *Step 2:* <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_step_2.jpg?1263241236' alt='' /> With one end of the nichrome in the slot, carefully wrap the nichrome around the core following the thread. You should have one loop around the slotted end - before the thread - and then follow the thread down. Once you've reached the end of the threads - add two more loops around the end. Though it is not critical, for best results, try not to have the nichrome overlap. You want the nichrome to have good contact with the brass. Check to make sure the nichrome is in the threads (not crossing over threads, the ridges are sharp and can fray the insulation. With the nichrome pulled taught, you should have about 25mm of extra nichrome on each end. It may take a couple of attempts to get it right. Just take your time and get an extra set of hands if you have trouble getting and keeping it wrapped. Once it is wrapped, bring the ends of the nichrome together and twist a couple of times. This will keep it in place while you add the ceramic and the ceramic cures. It is not critical that the two ends be exactly positioned. After you put the ceramic adhesive on and let it cure for an hour (or so) you will be able to free the ends and place them where you want them. So, at this point, just get it wrapped with the ends lightly twisted together. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_step_2a.jpg?1263241765' alt='' /> *Step 3:* <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_step_3.jpg?1263242402' alt='' /> Now that your core is wrapped it is time to add the ceramic. You can apply the ceramic using either the stick or brush. I'm using the stick. Dip the tip of the stick or brush into the ceramic adhesive. Slowly spread the ceramic over the nichrome. Spread a thin layer over the nichrome so that all of the nichrome is just covered. Try and keep the ceramic out of the inner threads but don't panic if you get some inside as it is easy to clean up - even after it dries at room temperature. If the ceramic makes sharp points when you pull your brush away add a few drops of water to thin the mixture. *Step 4:* <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_step_4.jpg?1263244410' alt='' /> Let it cure for about an hour at room temperature. We just need it to cure enough so that when you unwrap the ends it does not come apart. (Note: If you are in a hurry, you don't have to wait, you can proceed to the heating process immediately - it is just a bit more of a challenge.) *Step 5:* Warm up your soldering iron. We are going to solder the male pin to one end of the short hook-up wire and the nichrome to the other end. One end of the long hook-up wire will be soldered to the female crimp pin. However, before we do that we need to remove the crimp portion of the male pin from the pin itself as the crimp is going to used as the connector between the nichrome to the hook-up wire. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/male_crimp_pins.jpg?1263246071' alt='' /> <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/short_hook-up_wire.jpg?1263246578' alt='' /> Go ahead and lightly crimp the broken-off crimp on to one end of the short hook-up wire. You want to leave enough room so that and end of the nichrome can slide in before soldering it. When you slide the other end of the short hook-up wire in to the crimp pin, it should slide down into the pin itself. Go ahead and solder the pin onto the wire (be careful not to lose the crimp on the other end as it can easily fall off). You'll need to repeat this process for all four of your short hook-up wires. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/female_crimps.jpg?1263311682' alt='' /> Attach the female crimp pin to one end of the long hook-up wire. Don't place more than about 5mm of bare wire into the connector or the pin will not be able to slide all the way in. The connection between the male and female pins is very tight. You may need to use a small screwdriver to loosen up the female end if it is too tight. Step 6: After sitting for an hour, the ceramic should be pretty smooth (maybe a few bumps) and firm. Carefully untwist the wires and align them so that they are both on the same end of the core and about 5mm apart. (having the leads aligned along one end of the core simplifies the placement insulation over the core when the core is mounted on your heater barrel.) You may need to touch-up the ceramic after moving the nichrome around. (To avoid getting the wet ceramic all over the place, you should probably continue to get your heater core mounted and wired up for the initial heating, then touch it up before applying power.) You'll need about 5mm of exposed (insulator-less) nichrome. If you have a vise place the core in the vise and position the nichrome end into the connector on the short hook-up wire. Solder it all together. Once it is soldered the nichrome should hold firm. If it is loose, try soldering it again. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_cure_1.jpg?1263246589' alt='' /> <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_nichrome_lead.jpg?1263264638' alt='' /> You can see that I pulled off a chunk of ceramic after I untwisted the wires and was positioning them. First I'll finish attaching the hook-up wires, get it all set up for heating, touch up the ceramic, then heat it up. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_nichrome_leads_attached.jpg?1263311397' alt='' /> Now all of your wires should be soldered and you should be able to connect your crimp pins. Place an M6 screw into the brass core and place it in your metal "helping hands" or some other device that can handle 150C - 200C. We are going to heat up the core to quickly cure it. Notice there is ceramic on the exposed metal connectors to provide some electrical insulation. <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_in_clip.jpg?1263311741' alt='' /> Before heating If you are using ReplicatorG and a MakerBot extruder controller with v1.6 firmware: Once your core is firmly mounted and the wires are connected, connect the long hook-up wire to your extruder controller. In RepG control panel set your temp to 50C. The measured temp will show 0 since no thermistor is attached (if you have a thermistor available, feel free to use it). The core should begin heating up. Use a temp probe or place your hand a few centimeters away to confirm it is heating. If it is not heating, double check your wiring and connections to the extruder controller. Let it heat for 20-30 seconds, this will get it to about 75C. Then, set the temp in your extruder controller to 0 (zero). Your controller should go into a slow heat mode where the core will heat very slowly. Let it heat for three to five minutes. Somewhere along the way your heater core should steam for several seconds. After the heating period shutdown your extruder controller (turn off power) and let the heater core cool. If there are any problems with the ceramic - a crack, you missed a spot or you just want to add more, go ahead and add it then repeat the slow heating cycle. (Note: in RepG, after setting the temp you need to click in another field for the temp change to register. I usually click on the PWM field after changing the temp.) For other configurations the objective is to slowly heat your core up to about 150C and let it sit at that temperature for several minutes. This process gets most of the liquid out (in the form of steam) and hardens the ceramic. Once the steam is out then you can wire up your extruder and get started. I usually let a heater core sit at extrusion temp for 10-15 minutes before using it for the first time. Be aware that the first you heat your core to your operating temperature, it may let off more steam for several seconds. Keep your extra ceramic sealed nice and tight in case you need to do a repair in the future. Step 7: <img src='http://cdn.shopify.com/s/files/1/0030/7372/files/heater_core_after_initial_heating.jpg?1263311990' alt='' /> After heating If there is any ceramic on either end of the core, you may want to scrape that off if you need good thermal contact. Mount and start using your heater. Screw the heater into position on your heater barrel. Add your nozzle, insulator, thermistor, insulation and other items and then power it up. Depending on how long you heated it, the core is somewhere between gray and gray-white. As you use it, the ceramic may get whiter - this is normal. Your heater core may heat at a slower rate than a wrapped barrel. Depending on your configuration it may take a several seconds for your thermistor to indicate that it is heating and it may take 2-3 minutes to get up to operating temperature. Good Luck!! Please send your comments, suggestions, questions, etc., to feedback@makergear.com