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Good bellows?


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Should i buy  this bellows they are about 10 dolars 20 KM.

I think they are in bad condition. leather is teared and bottom board is twisted?
What you guys think.





And new  flaps should be put. With Shipping i think it would cost about 20 -30  dollars 50 KM.

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Note in double lunged bellows the hole to let air in is on the bottom board---I see that there is a spot where the bellows hook to the rope or chain  would go on that one.  Is it upside down on purpose?  (Having it on the bottom board means that the flapper naturally falls closed as you push air into the fire.)

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Yes you have right, i didn't noticed that valve collapsed by gravity. I think he  pictured that on purpose .

I think that he reversed sides up down bottom up those are double lung bellows, you can see by rods. Top chamber don't have hole in it, but it is not pictured, i cant see condition of top chamber. It is faced on ground.

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Having looked at an old commercially built one for ideas; I designed mine by getting the 2 sheets of plywood I could afford and then laying out the 3 solid pieces and 2 arched pieces so they would all fit. The nozzle I built  out of glued up dimensional lumber that I then drawknived to shape.  I used canvas tarp material that was heavily treated to resist rain instead of leather.

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A double lunged bellows has the center board mounted to not move, the lower board is raised with a rope or chain connected to a hook bolted to it and pushes air through a flapper valve in the middle board to the upper chamber. The upper chamber is the only one connected to the nozzle so air is always going out---you don't need a checkvalve to prevent the bellows pulling hot gasses/burning fuel back into the bellows as air is always going out that way.

When building the mounting frame it's important to get the handle to pump the bellows mounted at the right place so that it's easy to do a full pump motion.  For mine I had aframework that went up and across the bellows and down to the other side. on this frame work I put a loop of rope that I twisted to make a second loop where I inserted the bellows handle. I was able to shift the handle forward and backward and side to side allowing different people to adjust it to suit themselves----if two people were using the forge, one from either side, I would put the handle in the middle and adjust it backward so that a full stroke did not end with the smith's hand *in* the fire!

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I noticed that you can use airtight material as you want, but if it is not hard and less flexable it won't work, material for bellows need to be elastic and airtight but not too much elastic, because of durability i would say it need to be tough  almoust hard to squeze air from it, if it is material like nylon wich is airtight and waterproo bellows won't work  than again. 
It is airtight and all that stuff but it is not hard material to squeze air from.

It need to be as hard as it is elastic so it can squeze air and inhale top chamber. How many ounces  it have it is important but i don't know a lot's in that stuff.


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My treated canvas tarp material bellows was still going strong after around 20 years including some fairly abusive storage.  It was the material used here in the USA to make wind wings for oilfield drilling platforms back then.  I gave it away as I was moving 1500 miles (2400 km) and didn't have space to move it (and I could always build another pair...)

The arches that are mounted between the solid boards are to help keep them from billowing out during the compressive cycle.  Using canvas I wonder if rope could be sewn to it and fastened to the nozzle block to serve a similar purpose.

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I hope i would just have to put some leather patches on those holes, bellows  price was realy cheap, i would feel bad if sombady else bought it for decoration purposes.

If not anything i would have some nice project to work on,   i would sand wood maybe use somekind color i think i would bring it to life again.

I feel exited because this is my first leather (cowhide) bellows that i have.

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I will see what i would do to it, i hope that leather is restorable. There are couple of holes, valves need to be made new, wood is in bad condition some planing sanding could make job easy, but i don't guarantee anything,

It was with shiping cost around 20 dollars.

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The middle board is not supposed to move; so why interesting? In the second picture UP from the bottom: the bottom board is toward the top of the picture and the top board is toward the bottom of the picture.  The valves were probably simple pieces of leather I'd Fasten them at one point of the triangle and then in the middle of the opposing edge and let the other 2 points "flap".  How did they do theirs?

I made mine round and used light gauge aluminium sheet metal covered in glued on felt to make a valve.  Also a loose small hinge and a simple cage to keep the valve from flipping over in use. Gravity and air pressure makes them seat.

Remember the way it works is the bottom section feeds air into the top and the top feeds air into the fire.  So the top is solid and has no holes and the bottom and the middle board have holes with flapper valves.   Since the top is always pushing air out it doesn't need a check valve to keep from inhaling hot gasses from the forge .

Definitely trace the leather to make a pattern for you new set of "leathers".   The frame should suspend the bellows by the middle board letting the other two boards move.

You may want to sew  a cord to the outside of the leathers  on each section to keep them from ballooning out.  My larger double lunged bellows had arched pieces of wood to make an hollow center intermediate board between top and middle and middle and bottom boards;  (hinged as well), to keep it from ballooning out.

To fasten the canvass I used instead of leather I used small nails with large heads AND I ran a piece of pallet strapping around the edge of the boards outside punching holes in it for the nails.  Didn't need replacing in 20 years!

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Reason why i said it is interesting because middle board is same size as top and bottom, nozzle was made from one solid block that was save and basically attached to middle board, nozzle is not part off middle board it is attachment, (in books and in instructions on iforgeiron, i saw middle board that was way much longer than this, basically middle board is the same size as top and bottom, just it is somehow fitted in nozzle, and that 's it.

As about valve it would be harder cause wood is not flat, i would might plane it a little bit, but i do not know or i would use some bend shaped valve, cause like i said board is a bend.


Sou you think is it wasting if i try to stitch these one?

I don't think that i need ribs for this one or hooves as you call them, because bellows are too narrow , i mean one foot wide, i don't see problem with it sticking outside a little bit.

Those nails that i pulled out of bellow i believe they were hand forged, they had tapered shape, i think they were indeed hand made, you can't buy those in factory.

As about middle board i would nail one pice of wood on top of it for better support, because hole where were rods it can split i saw i would just nail or screw some pice of wood so it won't chip away at corner of bellows.

I  don't have  all time for those bellows right know, but i think they might work,

My one mistake was i wanted to restore wood , i won't do that anymore either, more you plane and remove root from it, it get thiner, i think i should concentrate on sewing this two pieces of leather instead, i think would can be leaved as it is, even if it root and decay i could easy change that, make new one, i won't touch wood to much, so i can test bellows how leather work and would they inhale top chamber.

One thing which is  new to me bottom chamber was twice larger than top chamber.

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I stiched one side side of bellows, next i would glue that, i find it more easy to stich than glue than again sttich. I used somekind  varnish for wood, this is beech wood.

I made one valve on middle board, put leather on it so flaps can seal.


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