RMiles Posted November 25, 2010 Share Posted November 25, 2010 This forge was finished the day before a demo. The first time I fired it was at the demo. It worked great. I used it for three days without a problem. The forge is based on text and drawings from "Manual of Black Smithing 1902". The bellows is 15.5 inch dia with a 6 inch stroke. It takes about 25 lbs of weight on the top to drive the second chamber for an even blast. The fire depth is not great so welding may be a problem. Using a bellows is alot more fun than a crank. Someday I plan to build a larger bellows for a shop forge. Quote Link to comment Share on other sites More sharing options...
Michael Posted November 25, 2010 Share Posted November 25, 2010 This forge was finished the day before a demo. The first time I fired it was at the demo. It worked great. I used it for three days without a problem. The forge is based on text and drawings from "Manual of Black Smithing 1902". The bellows is 15.5 inch dia with a 6 inch stroke. Very cool, very compact design. Perfect for demos! I vaguely recall seeing the plan for this in a book somewhere. Does the linkage lift the whole bottom section of the bellows? And its side draft too? Forging with charcoal or coal? Quote Link to comment Share on other sites More sharing options...
RMiles Posted November 25, 2010 Author Share Posted November 25, 2010 I found that charcoal does not last long enough so I use coal. I take charcoal to demos to show the difference between charcoal, coal and coke. The linkage lifts the bottom half 6 inches which causes a blast that also lifts the top half bellows about 4 inches. 25 lbs of weight causes the top half to extend the blast. The side draft nozzle is one inch off of the bottom. This is the first time that I have used a side nozzle but did not have a problem with fire control. I simply fed coal from each side if the air blast. Lindsay Publications Inc carries the book that I used. All of the dimensions and text do not agree so some dimensions must be your own. That is the blacksmith way. Quote Link to comment Share on other sites More sharing options...
John B Posted November 25, 2010 Share Posted November 25, 2010 Nice job Mr Miles, you have done a good job there. If you need weight on the top bellows, the old ones had a thick cast disc supporting the centre pin guide, a steel disc would perform the same and look more attractive than the brick. I have an original one I could take a picture of and post if you think it may be of benefit to you. It is also not essential to line the hearth with clay,(around the tuyere is ok) in practice they work alright without, and the base does not get that hot, Quote Link to comment Share on other sites More sharing options...
Nakedanvil - Grant Sarver Posted November 26, 2010 Share Posted November 26, 2010 What a wonderful kit! Looks like you had a lot of fun putting it together, should serve you for many years. The plumbing looks a bit small and is probably making a bit more work out of it and limiting the output some. But hey, If it's working for you, great. Just something to tinker with someday. The flex looks a little out of place, but you know that and probably have been thinking of what to replace it with. Thanks for sharing that! Quote Link to comment Share on other sites More sharing options...
Aaron J. Cergol Posted November 26, 2010 Share Posted November 26, 2010 Very cool! I love the "english bellows". I see a lot of them, but I don't often see people reproducing them, kudos! also, nice decorative touches on the forge stand. does the book go into any detail on the bellows? Thanks, Aaron Quote Link to comment Share on other sites More sharing options...
Grafvitnir Posted November 26, 2010 Share Posted November 26, 2010 Hasluck's "Smiths' Work" has the same chapter as the "Manual of Blacksmithing" on making the portable forge. (I've read both) You can get it here (legal download because of copyright): http://www.wkfinetools.com/mLibrary/Hasluck/1904-smith%27sWork/1904-SmithsWork-Hasluck.pdf Chapter IX pg 131. It's detailed but it's not the complete, triple chambered, English round bellows. Hope it helps!! Rubén Quote Link to comment Share on other sites More sharing options...
RMiles Posted November 26, 2010 Author Share Posted November 26, 2010 Glenn: I did not make drawings of most of the parts but made notes in "Manual of Black Smithing". I did take some photos of the bellows in process. I'll get some dimensions this coming week and make some drawings. Quote Link to comment Share on other sites More sharing options...
Ramsberg Posted November 28, 2010 Share Posted November 28, 2010 Hey Rmiles, Cool setup! The head area would be 188.7 sq in and with 25 lbs on it would be producing a blast pressure inside the bellows of 3.66" of water. If the head weight itself wasn't included and it were five pounds then the pressure would be 4.4" of water. Both of those figures are right in line with what seems to be required for most forges, although maybe a bit high for a side blast type, maybe the wrinkled bendy tubing is thwarting the air passage a bit, it works and that is what matters most. What diameter is your tuyere? Each 6" stroke of the bottom bellows would give approximately 1,000 ci of air, assuming some loss of volume due to the crimping of the fabric and the volumetric efficiency of the suction action of the pump. So, around 1 and 3/4 pumps of the bottom bellows would give one cubic foot of air. If you would indulge a curious mind, could you count how many strokes you make of the pump in one minute when operating the forge? That figure divided by one and three quarters would give the approximate number of cubic feet per minute of air that is pumped. Caleb Ramsby Quote Link to comment Share on other sites More sharing options...
Nakedanvil - Grant Sarver Posted November 28, 2010 Share Posted November 28, 2010 So Caleb, I see you're interested in steam cars too, eh? Quote Link to comment Share on other sites More sharing options...
Ramsberg Posted November 28, 2010 Share Posted November 28, 2010 Hey Grant, Oh yeah! About a year and a half ago I switched from working on a steam car design to working on a steam motorcycle design. Not a steam powered bike, but a motorcycle, the design goals are 450 lbs dry weight, 1/4 mile in 9-10 seconds and 30-40 mpg in the real world, at first glance that sounds impossible and many steam experts believe it to be, but we will see. The burner is designed to run on any liquid that will burn. The boiler, engine and condensor elements are now finilized in regards to their basic design and many details have been worked out. So I am getting closer and closer to the point when I will have to start building and testing stuff! It has been a long eight year road to where I have gotten in the steam design now. I hope to make the levers and brackets via hand forging, it should be rather unique(if it ever gets built!). Caleb Ramsby Quote Link to comment Share on other sites More sharing options...
RMiles Posted November 29, 2010 Author Share Posted November 29, 2010 John B: I would like to have pictures of an original bellows forge. The piping is the part that interest me. I used what I had. It doesn't look that good but it works and lets me remove the hearth. The hearth sits on cross braces so I lined it to keep it from warping. A friend said that he makes side blast of fire clay castings without a metal tuyere. I thought about that but had some iron so I machined it. I can replace it if it burns out. Ramsberg: The nozzle in the tuyere is 3/4 inch dia. The piping and block in the bellows is also 3/4 NPT. I used the dimensions in the book. There is alot of resistance to air flow in the system. The upper bellows takes about 2 sec. to lower with 25 lbs. of weight. This limits my stroke time to 25 strokes a min. With that I get a good steady blast. When I was building it I guessed at 40 CFM? Grafvitnir: Thanks for the info on "Smiths' Work" I'm trying to edit the pictures from that pdf file with the dimensions that I use. Quote Link to comment Share on other sites More sharing options...
Marksnagel Posted November 29, 2010 Share Posted November 29, 2010 RMiles, Wow! You've done a great job. Thanks for posting the pics and the info. Look forward to seeing more. Mark<>< Quote Link to comment Share on other sites More sharing options...
John B Posted November 29, 2010 Share Posted November 29, 2010 John B: I would like to have pictures of an original bellows forge. The piping is the part that interest me. I used what I had. It doesn't look that good but it works and lets me remove the hearth. The hearth sits on cross braces so I lined it to keep it from warping. A friend said that he makes side blast of fire clay castings without a metal tuyere. I thought about that but had some iron so I machined it. I can replace it if it burns out. . Hi Mr M, I seem to have lost or misplaced the pictures that I had, the transfer tube you have was a casting on the ones I had. Basically a tube with a right angled exit at each end, one end was secured onto the exit from the bellows, and the other end bolted to the rear of the tue. There were also two large iron balls suspended from the top bellows that provided the weight required to collapse the top section, not just relying on the plate and guide as I mentioned before Quote Link to comment Share on other sites More sharing options...
Ramsberg Posted November 30, 2010 Share Posted November 30, 2010 Hey RMiles, Thanks for the info. Those 25 strokes per minute should be giving around 14 1/4 cfm from the bellows. Going through the 3/4" nozzle, with its .44 sq in opening would produce a nominal velocity of 77.7 fps, using a discharge coeffecient of .8, that would be an area of .352 sq in and produce a velocity of 97 fps, just about 66 mph. The head resistance at the nozzle would be around 2.16 inchs of water. The rest of the head produced by the bellows must be coming from resistance in the piping. These are all aproximate numbers since the volumetric effeciency of the bellows, crimping volume reduction effect of the fabric and discharge coeffecient of the nozzle are all assumed and estimated. Caleb Ramsby Quote Link to comment Share on other sites More sharing options...
Nakedanvil - Grant Sarver Posted November 30, 2010 Share Posted November 30, 2010 Just cause you like playing with numbers so much Caleb: What about the clearance volume that remains under what ever pressure is required to open the flap valve? That would have to re-expand to atmospheric before the bellows could draw in more air. Might kick your numbers down .9? Some of this is enjoyable just from a backward engineering point of view. Mostly we just use the empirical approach or "try it and see". Quote Link to comment Share on other sites More sharing options...
Ramsberg Posted December 1, 2010 Share Posted December 1, 2010 Hey Grant, Absolutely right, that and the slight vacuum required to suck the air into the bellows(pump) are principally what add up to make the volumetric efficiency of the pump. Caleb Ramsby Quote Link to comment Share on other sites More sharing options...
connor bachmann Posted December 1, 2010 Share Posted December 1, 2010 I WANT IT.. Lol it is an awesome forge, I would LOVE to use it Quote Link to comment Share on other sites More sharing options...
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