apexmateria

cut a piece of steel off an old wood stove, going to bolt it to my workbench.. I need to cut another slab off tomorrow, which I'm not looking forward to. I don't have the right tool so it takes forever.

Any chance you could do a very basic image to explain the exhaust port concept? I can't visualize what you mean unfortunately.

I don't have a block of copper but I do have enough 2-3" pieces of 1mm thick cut copper wire that could fill the square 10" steel vessel. Steel mesh could hold the copper pieces in place. Copper doesn't have any issues with giving off dangerous vapors at high heat right?

Ideally I'd like material that radiates heat for long periods of time so I don't have to make fires often. I work for 4-5 hours at a time, my work space is roughly 10 feet squared with no insulation and a crappy tin door that lets winter air in through the cracks . To make it even worse I need to mount the heater at should level because I have no space on the floor for it. I'm not sure I'll have enough mass to actually heat the room, it should be interesting to see if it actually works.

PS - You asked about how I thought up the design earlier and completely forgot to mention this guy:

It's basically a modified version of that. Just wanted to make sure he gets credit.

^ Thanks I'll try preheating the metal before I do any welding today. I've been using a large steel brush on a drill to clean the metal I'll try grinding.

Thanks George for the helpful criticisms. You're right the fire area is very small and will require attention every few minutes. My hope is that the mass is small enough that it will heat up very quickly and radiate out lots of heat so I won't need to keep a fire going for long periods of time. If I had to remake it I'd definitely go with a gravity fed J-burner design instead of the L shaped burner I have now.

That's a good point about the exhaust potentially not being able to move through the system. I considered it as well and I'm just not sure. What I'm going to do is put lots of clay around that entire area temporarily to see if it works, if it doesn't I can pull it off and try only insulating the center pipe.

It's too expensive to buy a large aluminum brick and I think it might melt. The guys who build rocket heaters seem to use cob (clay / sand / hay mixture) as the heated mass. They have huge areas of mass to store heat while I only use a very small area by comparison, so mine needs to be as efficient as possible. If you have any other ideas about what would make a good heater block please let me know! Consider the temps get VERY high.

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The actual combustion temperature inside the RMH is probably between 1500 and 2600 F cooling off slightly at the beginning and end of the burn cycle.

Basically I just researched rocket mass heaters for a few hours to understand how they work, then tried finding a really small one to copy but couldn't find anything like what I wanted so I just made up a custom design. 

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Steve - yea those welds are terrible lol. Not like my skill level is great but my welding setup is very bad. My machine is cheap and under-powered, it can barely strike an arc and the welds barely penetrate. I welded some feet on the bottom of the L burner and those were some of my nicest welds yet, but I could easily snap the piece off. When I tested the 48 amp welder at a friends house it was like night and day difference. For the press I'm going to try constructing it with very minimal reliance on welds (I'm thinking about using 2x  1/2" steel brackets and industrial bolts on each side to secure the central plates).

Good advice thanks, I'll certainly do that. I'll be using hardwood as fuel.

It's a bit hard to explain but I'll give it a shot, here are some pictures to help. This first pic shows how the central pipe is cut open to allow cooler air to drop down and pass into the secondary pipes towards the exhaust:

10/10 welds?

How it's supposed to work is that there's an extremely well insulated fire in the center of the tank. The heat travels up the center pipe and heats the top block which carries a decent amount of clay and steel mass - it radiates out heat. The cooler temperature exhaust travels down into the adjacent exhaust tubes welded onto the central one. The exhaust is shot back into the propane tank where it is pushed into the external exhaust, and finally out the chimney. All central pipes should be quite well insulated. I'm considering either using ceramic blanket and castable refractory on the pipes directly under the heater core or cob. I think I'll probably go with cob since there's less chance it gives off any nasty fumes or particles.

UPDATE: Got very delayed on the press because I've been setting up a new workshop. I'm building a micro rocket mass heater to keep things toasty in the winter, it doesn't have the heat core and exhaust welded on, still needs lots more work. I've never seen a mass heater this compact and the design is experimental so it will be interesting to see if it actually works.

My welder at the moment is 20 amp running on 15 so it's making the project drag on longer than expected. It makes it hard to sustain an arc. I have a more powerful 48 amp welder to use but I'm waiting on an adapter.

On 12/12/2020 at 6:10 PM, jason0012 said:

I am curious why you need 90 tons. A 12-16 ton press will move a lot of steel. Log splitters really are the budget way to go. 18-24 tons in a pre-built system for under $1000 is a pretty good start, and enough power to work some decently large stuff.

I have no need for a 90 ton press at the moment but there's no telling what I might want to use it for in the future. I'm getting into custom metal fabrication and automation. Was thinking of converting the press to run on 3 phase power in the spring, I want to try to automate sheet metal stamping.

The bottle jacks arrived, had to special order them for some reason. $99 CAD/unit seems dirt cheap. The metal frame for the press is soaking in vinegar to remove the rust. I still need to source more plate. Going to the salvage yard tomorrow..

Commercial link removed as per TOS

I managed to find some castable refractory locally (heatcrete 27 m) it's $60 a bag.. I'm concerned about the max temp rating of 2700F

I could buy some Kastolite 30li plus -- but it will cost around $140 for the bag with shipping - it's rated at 3000F

Will heatcrete 27 be ok? Anyone have experience with this product?

Does it do well to resist borax? Can handle forge welding temps over long periods of time? 

The reason I mentioned that example was because I just watched a guy do it on video. He used a manual 4 ton jack inside a very simple welded frame and he punched through 2-4mm cold steel plate clean and easy (it warped the surrounding metal a bit but overall it was a clean punch). In the same setup guys are easily crushing 2mm thick rectangular stock (1" diameter) into a flat bar. With 20x the crushing power of their setup (and a much, MUCH beefier frame) I think I can push a billet together. I maybe wrong, and I'm very open to admitting that.

I'm ok with learning through failure as long as 1) it's only time and money on the line 2) I don't get seriously injured or die.

I believe there's enough possibility of success to give it a try. I'll update sometime in the coming weeks!

Even just touching the bars puts little specs of chrome onto my fingertips (because the rust is slowly flaking it off). Kind of a shame because it's so much metal that would be useful for projects, it is what it is though! Thanks guys, appreciate you helping me out. I won't grind or cut them. I'll find a safe use for them one day.

Frosty don't worry I'm not planning to win a Darwin award anytime soon! I'll ask you guys for advice along the way to make sure it's as safe as possible. My cousin is a talented machinist so he can help me too. Thick steel and very large industrial grade bolts will be used. I'll try my best to make sure it's very basic but safe.

ThomasPowers I don't know almost anything about physics or thermodynamics but if I hammer a cold 4mm thick piece of mild steel plate 50 times it will be slightly dented up, if I create a punch using a 4 ton jack it will tear straight through the cold metal in seconds (very easily and quickly with much less effort). Something to do with leverages, gearing and concentration of force I think. I don't really understand it and haven't looked into it much. Same principle may apply to crushing a billet?

Thanks for the help Frosty, dealing with metal vapors sounds slightly terrifying I'd prefer to avoid that

https://multimedia.3m.com/mws/media/40744O/3m-respirator-cartridge-and-filter-selection-poster.pdf

Is the 3M 6001i a suitable mask?

Should I maybe strip off the chrome before grinding instead? I see there are some methods floating around using acids or electrolysis.

I'm really curious how it would move the steel as well. From the videos I've seen a modified 20 ton log splitter will compress a billet like butter. I'm get you though, even at 90 tons the manual jacks seem like they might not perform well.

I wonder how much force I'll have to exert on the jack on each stroke (while its compressing a large billet) because it needs to go up and down FAST, repeatedly, multiple times per second for the cylinder to move at a decent rate. I could definitely see the project ending in failure, but I do think there's maybe potential for success. Spreading the load across 3 jacks might really help if I can make it feel seamless.

Next issue is the cost of the frame is it possible to make a stable frame for around $150? I'd need thick blocks of metal for the press plates as well. Any recommendations are appreciated.

At the moment I only have n95 masks. My respirator is this model but has no filters. Any idea what kind I need?

I need it to keep me safe from refractory fiber as well since I'll be building a forge soon.

Can open and close the 3 bleed release valves based on a lever of some sort. I played around with a bottle jack in my garage and it seems possible.

If I get strong springs to pull down the cylinder it should only take a second to drop 1 centimeter and then I can rotate the billet, quickly shut the valve in 1 pull and start pressing again. Manual jacking is slow but it's especially bad to have to jack up the full length of the cyclinder. Jacking 2-4 CM of total distance doesn't take long from my test on an old 3 ton bottle jack. If I go really fast I can do 1CM of distance in 1 second.

I'm getting the itch to try and make it.

Thanks for the warnings, good to know! At the moment I need to cut a slot down one of the pipes with an angle grinder. Can you guys advise me how to proceed?

Should I just sand off the chrome paint / plating where I want to cut? Is paint stripper / vinegar a better option?

Frazer - OD = 1".

bubba682 - I appreciate the input, especially the constructive criticism. it can save me lots of wasted time and money. I'm trying to think of a workaround to get past the speed issue.. it's a tough drawback! The force is controlled by manual jacking.

Johnytait - I need a very powerful press for cheap, from what I've seen nobody has made one yet, it might not be possible. All the good presses are out of my budget so I have no choice but to try to innovate / improvise (which might end up being a waste of time - I'm ok with that). I might not build it, but it's worth doing a bit of brainstorming.

ThomasPowers -  I think maybe one thing that can help counteract the speed deficit is the sheer amount of pressing force. It should be able to crush a billet as much as I need in 1 single pressing cycle. The slow part is the release and "reset", I'm trying to think of ways to reduce that.

Latticino - The problem with a power hammer is that I'm surrounded by fragile suburban people . They will call cops / bylaw. I'd have to rent a garage in an industrial sector to use it. A press would be ideal since it's relatively silent.

Is this possible or do the parts not exist? I'm thinking of taking out all 3 bleeder valves and merging those into some kind of high pressure "master release valve". Basically it would look like this:

This high pressure valve is just a random one pulled off google images. The idea is to have a centralized release mechanism that can drop the pressure on all cylinders at once just enough to break the clamping force and back the cylinders off by 1-2 centimeters. I'm not sure if this even exists since 90 tons of pressure should have a PSI high enough to probably destroy most specialized hoses and valves fairly easily? The price of those hoses and valves might make this project a no-go as well.

I tested the handle material. It's extremely hard and dense wood - it holds up well to chiseling (clean small chips come off), it takes forever to file down and sand (even with a rasp), and if I take a very deep gouge out of the wood it will finally start to splinter, if I smash the wood against something it barely dents. I should have spent some time to ID the type of wood first, hopefully it turns out ok! I'm a bit worried about it snapping at the thin point where the hammer head connects.

I spent a few hours watching DIY hydraulic press videos and reading. It seems a lot of people on a tight budget are modifying log splitters into presses. 4-6 ton splitter would cost around $300 including the price of modification, it's quite weak though. The 20 ton splitters are 1k or more (used) and they require an electric motor to replace the gas one etc. I think building an electrically powered 20+ ton press from the ground up will break my budget by a large margin.

I made a thread here about my cheap press build idea, please check it out and critique: https://www.iforgeiron.com/topic/66791-90-ton-hydraulic-press-for-under-500-mockup/

I need a cheap but powerful hydraulic press in the $300-500 range to help with forge welding / making damascus on a budget. $200-300 log splitters are too weak, $1500+ log splitters are powerful but expensive, a $5000-10,000 industrial press is out of the question for me.

I think an automatic press would be too expensive (just the motor alone will probably go over my budget), plus it adds lots of complexity to the project. So instead, I'm thinking about keeping it cheap and simple by using manual jacks. I can get 3x - 30-ton bottle jacks from princess auto for around $350 total. The rest of the money would be spent on the metal frame. Overall it would have 90 tons of total pressing power for under $500. 

I can think of some possible issues:

• Getting 3 presses to all work in-sync. If one is pressing more than others it can put negative strain on the system.
• Releasing pressure from all the bleeder valves at once. (I think I have ideas to solve this) 
• Inability to lower and raise quickly - slow reset time

Please critique the build idea as much as possible. Are there any issues I'm not thinking of?

I made these rough mockups in photoshop, click image or here for full size:

Note the frame in the image is just a rough mock-up it would be re-enforced where necessary.

Decided to make the 8lbs head into a mini 2h sledge with a stained custom handle, and then put a very basic handle on the 2.5lbs head.

They're both the same wood for the handle but I'm not sure what it is. It's very dense and seems resinous. The wood was original used as shutters on a house.

What kind of metal are these? Cheap steel? They're around 3-4mm thick and I have 30 in my shed, they're from my grandfather (he passed away).

I want to grind some or maybe even heat them to use for projects. I assume it's safe since they're rusting it means no zinc plating right? Should I strip the coating off first as a precaution?

Mikey98118 - I think you're probably right!

pnut - Yeah I tend to do that. I don't like to follow the traditional path of learning. I like to laser focus on what sparks my interest regardless of difficulty.

ThomasPowers - What kind of pressing force is acceptable? Are there any DIY tutorials you can recommend for making a decent press for $300-500? Unfortunately I'm living in the hellscape known as suburbia and can't setup any water powered machines. I should be moving out into a rural off-grid area in the next few years but right now it's not an option.

I just sent him a PM. Thanks!

ThomasPowers I might try to heat treat 1 or 2 steel knives made of O1 tool steel then I'm going straight into making damascus. My first few billets I'll practice forge welding cheap metals together. Making pattern knives as gifts for family and neighbors is my main goal. I really want to make mosaic damascus. I have no power hammer but I think I might have an idea how I can get around that and use a shortened 2H 8lbs sledge and a customized clip to hold and rotate the billet.

Irondragon thanks for the tip! Will pottery / HVAC supply companies have that for sale? I live in Ottawa, Ontario. Was going to order everything from a forge & farrier website but they don't carry that product. If I can find Plistex as well as everything else I need in 1 place I'll get that instead.