jcrous

Thanks.

I am now back from my holiday and I expect my new laptop tomorrow, sow I will be busy migrating to portable, but I have taken some pics of a museum that have reconstructed an open air scene. I will post when I can.

The reduction is one revolution of hand crank gives 50 turns of fan blade.

12" diameter x3" thickness x 25-1 ratio would take a very strong arm to turn.

OK, if I get it right yours is the 50:1 for a 11"X1" fan.
Now I think I understand why the blowers have such a long handle. Then I think I must calculate for a 30 rpm turn of the handle. With a 50:1 you will get the fan to turn at 1500 rpm.

If I work with 7:1 X2 and I turn the crank at 30 rpm I will get 1470 rpm for the fan. If I get the fan to the 11" X 1" dimensions, I think the torque will be more or less the same, but I can try to improve on the blade design.

Thank you for your information, that was what I was looking for in the first place. Now I know what to look for.

Unfortunately I live in South Africa, so the shipping and import tax will kill me.

I would like portability. My first choice would be the real one but if it can not I would not mind to make my own. I personally would prefer to use proper cast iron pulleys above bicycle rims. I have seen them in the past and I just need time to look for them.
I will look at a fan diameter of at least 12 inches and about 3 deep. I am planning to use about 8 fan blades with a rather tight fit. As I have mentioned I would like to melt brass too in my forge. I have access to good resources as I own a lathe and both gas and arc welder. I also have access to mig and TIC and spot welder at my cousin, so I will be able to do it. When finished, I will publish the blueprint.

I have visited the auction shop but the grinders are not what I want the bigger gear runs directly against the second axle, into which were milled slots to resemble a gear. Low quality. I will rather wait.
I am going on holiday in three days time and then I will hunt all the antique and second hand shops in several town. Maybe I will get lucky. If not I will buy a set of gears and rather take the long way.
I will also look at a more effective way of making the fan blades.

I immediately searched for Viet Nam blacksmith blower, and I came across this link:
http://www.iforgeiron.com/forum/f92/blower-rebuild-advice-needed-14397/index2.html.
I can maybe start on the formulas of this setup, but I am sure I can design a blower that will have a more effective fan and then maybe I will only need a gear / wheel setup that will be slower.
I worked in my thoughts with the following:
Ypu can crank a blower at about 100 turns per minute. The 2 sets of gears are 1:5, therefore the first set will turn at 500 turns per minute and the second one then at 2500 turns per minute.
This is maximum. You may need to turn much slower, or the flames may be too hot.

Maybe I am totally wrong in my assumption.

ThomasPowers,
I have thought about that some years ago, but I think it will be too slow still. The gear ratio may be

Thanks Rub

I was serious when I posted the question. Information of who can answer my question will also help.

A Cast Iron anvil is not the end of the world. A late friend of mine had one and he used a milling machine (fly cutter) and skimmed a section of the top face so that it was lower than the table and the n he added a hard piece of milled / skimmed hard steel which he welded in place. He used that revamped anvil without problems and in cost him very little.

Hello,
I would like to know the following information about a hand crank blower:
The gear ratio: number of teeth of the four gears and the diameter of the fan-

example:
first gear (mounted on shaft of handle) 120 teeth
second gear 30 teeth
3rd gear (angled teeth) 120 teeth
4th gear (angled teeth and mounted of fan shaft) 30 teeth

or

1 complete turn of the handle will turn the fan blade 16 times
plus
the diameter of the fan.

I do not mind for several replies in different formats. The second option may be the easiest option.

I am trying to figure out the second option and the size of the fan.

I am tired of searching and waiting to try to get hold of a hand crank blower. so I will try to make my own. I think I will be able to get hold of the gears, but I may have to use a gear train of six gears. If I succeed I will make a blue print available. I have seen what others have done and I am confident I will be able to do it as well. Even if I have to turn the bushes or bearing housings myself, I will do it. Let's call it my personal "anti passing of the years and the unavailability of old stuff" campaign.

Any photographs of the fan's prop will also help. However I may make the fan part of more modern design.

Thanx
I am also looking for a rivet forge or similar.

Hi,
I am now interested in starting hobby blacksmithing for quite more than 12 years and have not started yet.

I have one tong, hand cranked grinder (antique), a blacksmith's pole vice and I also have a 100 pound Londen anvil (no dents or marks yet).

The grinder and the anvil was given to me as gifts. I bought the tong as scrap but bought the vice for some money, before everything became expensive.

I have all types of modern tools, even a screw cutting lathe.

However, before I can go further I must build a forge (I prefer a coal forge as gas are too expensive). I have browsed around, but I am still looking for a fan or plans for a fan. Maybe I must buy the gears and make my own design for a hand cranked one. The fan part will not be so difficult. I had something that were used to spread sulfur dust om treas but just as I managed to melt bras the little gear box unit ceased up. I will therefore use my forge as a little furnace as well for aluminum and brass.

If anybody can direct me in some direction I will appreciate it.

Lucky devil.
Normally some people will be shy to share knowledge in fear of losing business to possible competition in future,

I am new to this forum, but I must say that I am of the opinion that DenniG have made a very nice job. Do what you believe in and it will succeed.

I decided to raise my lathe's mandrel as well as made it thicker, with a bigger size hole through. Everybody said I was crazy, but the satisfaction when I succeeded and proofed it worked! That was my biggest reward.
I would like to see the horn when finished.