Hello all, My name is Roger (Climbing96)

Discussion in 'New member introductions' started by Climbing96, Oct 19, 2021.

  1. Climbing96

    Climbing96 Copper

    One last pic. This one is closer to being relevant to this forum as it is an oven, but not so much due to its size and temperature range. We designed and built this our self. A great friend designed the oven, and I designed and built all the electricals/electronics. It is 8' x 8' x 16' inside dimensions. Now I just need to scale it down physically, and scale the temperature up. Then I will be ready to go;-)

    KIMG0196.jpg
     
  2. Al2O3

    Al2O3 Administrator Staff Member Banner Member

    On the pumpable cf I probably used 1/2 a 5 gal bucket for body lid and base. I still have 1/5 of the bucket. Laying it on 1/4 inch thick it would take several days to dry or overnight with forced air. You can fire it immediately wet but my plug materials couldn’t take heat. It will shrink so thicker layers will shrink more but it can be patched and built.

    For composite molds your size I always incorporated a compressed air port centrally. Once the compressed air gets under a little area it will rapidly expand and release the whole thing with no fuss.

    Best,
    Kelly
     
  3. DavidF

    DavidF Administrator Staff Member Banner Member

    Welll......
    I'm impressed :D
     
  4. Climbing96

    Climbing96 Copper

    We have a wedge that has an airline connection to it, but we found that it was a stupid design due to the air being fed between the mold and part would just escape through the gaps created by the wedge. How did you keep the resin from plugging the hole of the air port during the cure cycle? Did you plug it with clay that was removed after curing? I do plan to put air ports on the future molds we make, and hopefully this makes de-molding much easier on the molds, parts, and ourselves. I have heard of others trying this method, and for some it worked well, and others it didn't. Before my time with manufacturing these trailers, the company that was manufacturing the bodies for the owner had a part that stuck into the mold and they could not get it out. Not sure why this happened, but they drilled a hold through the mold to the part and attempted to put air pressure in it to release the part. It didn't work. Not sure why, but when thinking about psi (pounds per square in), there isn't much force at first due to the small hole. For a 1/4" hole(0.049 square inches) and 100 psi would only net about 4.9 pounds of force (assuming my numbers are right). Once the part starts to separate, the force climbs quickly. Again this was before my time and I am not sure if the person who laid up the part forgot to put mold release on, or the mold release was bad, or if there were cracks in the mold that allowed the part to become captured as epoxy flowed into these cracks. Just guessing. Aluminum molds will be much more durable, and much less likely to crack. Easier to polish for a smoother more non-stick surface. I will experiment with some smaller molds to see how they work out, but I have high hopes for success;-) The trailer I am designing now is a single wheel trailer that leans with the motorcycle and has a 6.5 gallon fuel tank built into it. I am testing it now, and it is working quite well. I may attempt to make an aluminum mold for the box that gets strapped onto it. Right now, I am suggesting a 35 gallon Action Packer that can be found at Home Depots and Walmarts. Making a mold to make a box for it would be a smaller test before jumping into the deep end. I can CNC router the mold master out of foam (thought that might put a twinkle in your eyes), cast them, and then test them with a fiberglass lay up. That might be a much sooner project than the larger MC trailer bodies, and a great learning experience. Here is the first prototype I tested on a trip (I am now onto my 2nd prototype that has the 6.5 gallon fuel tank completed). This is the first of 4 models of trailers I have planned. The 3rd model will be the first one that requires the fiberglass body which will be a two wheeled camper trailer. All models will be towed behind motorcycles. The elevation in this pic is 12,960 feet. Not bad for a fully loaded trailer that has the necessary tools in it to change tires (from street to dirt) and have the minimal necessary tools to balance them too. Not to mention food, clothes, camping gear, and other niceties.

    Later,
    Roger
    California Pass Resized.jpg
     
  5. Al2O3

    Al2O3 Administrator Staff Member Banner Member

    I just had a dowel to fill the hole and placed a pressure sensitive adhesive dot over it to seal. Then just normal release procedure but I wasn’t using heat cured resin system. Upon curing, lightly rap the dowel in the hole to increase the working area of compressed air and then gradually increase pressure with a regulator.

    Best,
    Kelly
     
  6. Climbing96

    Climbing96 Copper

    Well, I should be receiving the IFB's this coming Monday. I ordered the IFB's before coming across this forum, which is the nature of the beast. I have just ordered the electrical bits for the build. I figure I will build my first furnace with these IFB's and then graduate to a better low mass furnace in the future sometime.

    Kelly, I know that you suggested using ceramic insulation board, and I really like the simplicity of how you explained in another post to build it. What is the trick to keeping the cost of using ceramic insulating board down? My numbers just for the board was north of $700, but I was not taking into consideration using the circles cut out of the center, which I guess would be like piecing together an IFB furnace.

    It looks like once all the parts arrive, and I have time, I will graduate from the introduction thread into a build thread. This will be a new adventure for me. I am so used to building stuff by myself, and then at the end saying, "I guess I should have taken some pics along the way!" This time I will actually have to remember to take some pictures. Probably the hardest part of the build;-) See y'all in the next thread.

    Later,
    Roger
     
  7. Al2O3

    Al2O3 Administrator Staff Member Banner Member

    Remind me Roger, what are the internal dimensions of the furnace you want to build?

    Best,
    Kelly
     
  8. Climbing96

    Climbing96 Copper

    Internal dims are 14" diameter and 15" tall for the main body. The base plinth and lid may take up a little bit of that height.

    Regards,
    Roger
     
  9. Oldarm

    Oldarm Silver

    Good evening Roger,
    I am not even thinking of getting in to Q&A or "Show and Tell" time regarding the glass moulding process of which I know little or nothing. But let us talk a little of the casting of your moulds. I seem to gather that you plan to make a series of castings which will be bolted together to form the whole. Nothing wrong with that fabrication system at all. That you are prepared to venture into the casting of these elements yourself raises your gonads to another level in my opinion.
    With regards to the building of your furnace. You have given the planned internal dimensions but what size crucible are you planning to use and allied to this query, what is the net, and or, gross, weight of the largest casting you are planning to pour.
    Just getting a little concerned/puzzled. I do hate to see a lot of time and enthusiasm go to "pot" and if we can avert issues it is time well spent.
    Regards, John. By the way, Never, never, ever give in!
     
  10. Al2O3

    Al2O3 Administrator Staff Member Banner Member

    As far as hobby furnaces go, it's fairly large, but almost the exact same size as my large furnace. Here's the build thread for the lift-off bit.......skip to the 3rd page for result.

    http://forums.thehomefoundry.org/index.php?threads/furnace-cart-and-lift-build.278/

    That furnace was intended to be fuel fired but does have a resistive electric section that can be added primarily for heat treating but occasionally melting. The refractory is a combination of 5/8" wall dense castable hot face, insulating castable flanges, and ceramic wool for outer insulation. It's actually fairly low mass for a furnace that size. Not sure what power level you'r thinking but for that size, I'd target at least 16kw.

    4 Main Body and Bore.jpg

    My 10" bore lift-off is 8kw and can accommodate an A20, which I can manage by hand, but the larger furnace can take an A60. With aluminum, crucible, and shank, That's North of 125lbs, so I built a gantry and hoist to manage pouring (skip to last page for result).

    http://forums.thehomefoundry.org/index.php?threads/gantry-crane-–-a60-crucible-handling-equipment.1703/

    The best I've seen for CFB is about $120 for 20' x 40" x 4" but you need to add another $50 to get it shipped so you'd be in the $340 range for just the body. I can post a source if interested. The reality is a furnace this size takes some material to build. Least expensive (but probably not by a lot) would be castable refractory and ceramic fiber.....but, it would take a long time to heat, especially in resistive electric. Here was my dense castable 10" bore build and how I cast the heating element shelves. The beginning of the thread also shows my IFB refractory liner.

    http://forums.thehomefoundry.org/index.php?threads/furnace-fail-reconstruction.209/

    Whatever combination of materials you choose to use, your thermal mass will be approximately the same as the actual mass because the base materials are all essentially the same.....alumina-silicates. I'd strongly advise that you buy and experiment with smaller quantities before you leap into the full blown furnace build.
    1. Castable refractory is strange stuff to mix and cast. Use vibration and power mixing or you'll be sorry.
    2. IFB comes in different densities/refractory ratings. I built mine from K23 (2300F) but I'd recommend K26. It cuts easily but creates lot's of abrasive fines. I wouldn't suggest using a highly prized tool to do so.
    3. Ceramic Fiber Board cuts easily with a razor knife but can fray and produce ragged surfaces when other cutters are used. Like ceramic fiber, the surfaces should be stabilized to prevent fibers from becoming airborne.
    Use a respirator when working with any of these materials as they are quite friable, easily become airborne, and can cause sever lung injury. For working 2 & 3, I'd suggest you do so outside. When I did my IFB work, I moved my saw and spindle sander out on my driveway. If you don't, you'll deposit fines/dust all ever your shop and they'll become airborne time after time. Sweep up as much of these materials as possible, vacuum the rest, clean your vacuum filter, change/wash your clothes.

    Honestly Roger, you might be way ahead of the game to buy a clapped out kiln (sometimes they can be had for next to nothing) the approximate size, cut the bottom out of it and voila, lift off furnace body with heating element shelves. Then build a base, and either use the kiln lid, or CFB for a light low mass lid. That would cut out a lot of labor and mess, and probably save a lot of money as you can rarely buy IFB brick as cheap as they come in used kilns. Then just fab your lifting mechanism.

    My 2 cents.

    Best,
    Kelly
     
  11. Climbing96

    Climbing96 Copper

    @ Oldarm,

    I appreciate the concern and a very real situation for many. I am guessing that the point you are brining up is that this furnace will not have the capacity to do what I want, and that might kill the flame or desire inside of me I know that this furnace won't have the capacity to do the molds for the fiberglass parts. At the same time I know that if my first furnace was big enough for those parts, that the smaller stuff I want to cast wouldn't suit that large of a furnace. My tentative plans are to build a 14" diameter furnace that will fit a range of "a" to C as far as size. The a size might be a little bit small for this furnace, but won't be excessively so. I will use this first furnace to gain some experience to find out what I like about it, what I don't like about it, and then when the time comes to go big or go home, I will make a larger furnace to do the job at hand. That larger furnace won't be a one and done project. I have a small hand full of projects that I can use that for, assuming the first one worked out OK. The size of crucible I plan to use with the first furnace build is on page 3 of this link (https://www.vesuvius.com/content/dam/vesuvius/corporate/Our-solutions/our-solutions-master-english/foundry/non-ferrous-foundry/crucibles/brochures/Crucibles catalogue (e)_.pdf.downloadasset.pdf) in the size of 50 or 60, which I think will give me about 30 to 40 pounds of aluminum capacity. I am also toying with the idea of making my own crucibles as that gives me the possibility of customizing the size. The friend of mine that I mentioned earlier that said he would help me with some of these projects said he made his own crucibles from steel. I was concerned at first due to reading and watching videos saying that molten aluminum will break down steel fairly quickly. One video says he gets about 5 to 12 melts from steel crucibles before they need to be retired. This friend of mine says he solves this problem by lining the steel crucible with clay (I didn't ask what type or what recipe). My tentative plan is to make a small crucible for testing and lining it with moldable ceramic cuz it doesn't wet with aluminum. Starting small cuz I don't know if the expansion of the steel is similar to the moldable ceramic, and that might cause cracking. If it works well, I will make my own crucibles If not, I will buy the ones from the link above.

    @ Kelly,

    Just your 2 cents! If this kind of education were this cheap and of this quality, this country would be in a much better place right now. Thanks for the link to the Furnace Cart and Lift Build. I have not come across that one yet. I have read all the way through the Furnace Fail & Reconstruction thread last week. When I read that thread, I was a little bit bummed as I have already purchased IFB's based on what I saw on the Vegoil Guy's videos, which are great videos, but I think I would have done a mix and match from his videos and what I have learned on this page. Well, probably more of what I have learned here, but still useful information.

    The link I followed that you posted for ceramic fiber board was $88 for a 2" x 19.7" x 39.4" board. I will continue to search for better prices. For now cuz bricks will be here Monday, I will cut my teeth with IFB's, continue to read and learn from this forum, and then when the time comes to remake the furnace due to failure, I will decide what material to make the new one from, and what size to make the new one. Turns out that my electrical bits are scheduled to arrive Monday as well, so as time permits I will start building and taking photos. It might be cheaper to buy a used kiln and modify it to fit my needs, but I have to say that building something from scratch is very full filling for me.

    Thanks to all that commented and made suggestions. I am a farter smeller....smarter feller now than when I started this journey. I don't know where folks here lay their heads at night, but it feels like they are right next door. Mind you that where we are here in Texas, right next door might be a mile away;-) Catch y'all on the flip side. Time to get to reading your Cart and Lift Build Thread.

    Later,
    Roger
     
    Last edited: Oct 29, 2021
  12. Al2O3

    Al2O3 Administrator Staff Member Banner Member

    The number in the A-series crucibles is actually the weight (usually brim full) with aluminum. The crucible in my previous crane/hoist link is an A60.

    Molten aluminum is like a solvent to other metals. Fe is soluble in aluminum and will diminish it's material properties, namely tensile strength and elongation. Professional foundries coat or use ladle liners to prevent metal contamination. If it's hobby casting non-critical parts.....a steel crucible is probably not much of an issue. The steel can also develop an oxide layer that slows the process, but there are members here that have gotten >100 heats from 1/4" wall steel crucibles.

    Angle iron and hot rolled profiles make good ingot trays because of the heavy oxide layer.

    mcf is a good choice for a ladle liner but a poor choice for a melting crucible because it is such a great insulator. There are ladle/kiln washes that are commonly used but they don't hold up well and require frequent maintenance, and are primarily intended for short contact in ladles not crucibles. Boron Nitride is very good, but besides being very pricey it will also be marginal in crucible service, but I use it to coat my metal contact tools.

    If you're going to be handling 60lbs of molten metal, buy a commercial crucible. Between building a furnace, molten metal management/lifting/handling equipment, mold material, flasks, etc, you've got some work ahead of you.

    Best,
    Kelly
     
  13. Climbing96

    Climbing96 Copper

    The link to the crucibles above shows the size capability in kg Cu on page 3 for the A-series shape. I scrolled down the page and found on page 5 that the size capability is listed as kg Al for the BP-Series shape. On the same PDF, it uses volume in liters as opposed to a weight of "X" material. Interesting how on the same PDF they use different metals to describe the size. I saw a video about crucible sizing, and they used a different format still. The first number was in pounds of aluminum, and the second number was in kg of brass. I guess different manufacturers use different terminology. Too much for me to wrap my head around, so I just used the dimensions to sort out whether it would fit, and ass-u-me'd the weights as I could determine that later and get better at interpreting crucible numbers once I had more experience.

    My thought on this was based on my understanding of home insulation. What I have read is that R Value is measured per inch of insulation. To talk about something right up your alley, looking at pink foam insulation, the 1/2" thick insulation has a lower total insulation value than say a 1" thick piece. If I were to make a steel crucible and put a layer of about 1/16" of mcf, I figured the insulation value would be negligible, and it might be a good isolation barrier between the aluminum and steel. Not to mention the ease of keeping the crucible clean. I have an empty propane bottle for a hand held torch (the taller thinner style) that I can experiment with to see if the liner will handle the heating/cooling cycles without cracking. To those that might be concerned, the way I have used propane bottles in the past is to depress the valve core to ensure there is no pressure remaining, put it into the freezer for awhile to make the remaining gasses less volatile, drilled out the valve core, and then filled the bottle with water. Lessons learned from my youth doing things I shouldn't have been doing;-)

    True that about a lot of work, but coming from a guy who casts his own pulleys and makes his own miscellaneous parts when available commercially (just finished reading your Furnace cart and lift build thread), I think you know where I am coming from;-) I have a tendency of getting into trouble so keeping busy is the best mode of protection. I do buy things that are available when time is of the essence, but when not in a hurry, the satisfaction of making it myself is very high. I don't know if this rings true with you, but a lot of times I will buy a product and think, "This is good, but it would be awesome if it had this feature." Hence the pleasure in building it myself. Right now, for the business, the focus is on the trailers, and the models have not gotten to where I need to cast anything yet. I figure to learn the art of casting before time becomes of the essence would be a good idea.

    Later,
    Roger
     
  14. Al2O3

    Al2O3 Administrator Staff Member Banner Member

    That's a strange mish-mash. Morgan A series crucibles are Aluminum designation.

    Even if I could have found pulleys that suited me, there was a bunch of them and would have cost a shed-load.......even so, only when building for fun but never when building for profit......but those days are mostly behind me. It's nice to build something because it scratches where it itches versus earning a living.

    A small percentage of those who have tried to make non-metallic crucibles are actually capable of succeeding and even those still typically have low performing crucible. The great thing about advice is you don't have to take it. For coating metalic crucibles look at the lubricoat products here.

    https://www.zypcoatings.com/top-selling-boron-nitride-coatings/bn-lubricoat-lubricoat-blue/

    They have acidic pH so if not applied to ferrous metal at elevated temp, expect rust. They actually recommend the more neutral BN Hardcoat for ferrous surfaces and it is more durable albeit slightly less lubricity.

    Best,
    Kelly
     
  15. Climbing96

    Climbing96 Copper

    They are surely proud of the BN stuff. Their description saying a lubricant/non-stick agent reminds me of conversations over teflon coatings. "If nothing sticks to teflon, how do they get the teflon to stick to the pan?" At the point that I decide to make a better furnace, I might have excess mcf to experiment with. I don't think I would spend that kind of money to play around with an idea, as the mcf is not cheap, but am wide open to experiment with material I have already. This is a good bit down the road, and I will contemplate crossing that bridge then, as much as I would like to try it now, that idea will have to be put onto the back burner. I will probably buy a crucible to prevent the side effects mentioned from being contaminated from the steel. The way my brain works is it is always thinking about different ideas, even if I am not ready to implement it at this time. I've had better ideas, and I've had worst ideas. Don't ask what the ratio is.
     

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