What size blower for forges?

J

jsmbrown

Joined
Oct 23, 2011
Messages
11
I am getting ready to build 2 gas blown forges. One out of an old Freon tank and one out of a 5 gallon portable air tank. I would like to only purchase one blower if possible and use on both forges. Can someone suggest a blower and or CFM size that will work for both forges?

Thank you.
 
I built 2 forced air propane forges, and I used blowers from dishwashing machines on both. I have a friend that works on appliances, and he gave me both blowers for free from the good parts pile.

if I remember right, the housings slipped right on to 2" black pipe nipples. the nipples went to gate valves to regulate air flow, and then into the burner I built. I dont know about others setups, but mine dont take alot of air, the valves arent even half open.
 
I do the same thing that Mr. Washburn does, though I “digress” even further. I go to resale shops and buy the used hair dryers for a buck or two.
 
CM Forge said:
I do the same thing that Mr. Washburn does, though I “digress” even further. I go to resale shops and buy the used hair dryers for a buck or two.
Click to expand...

I have a propane forge already that I use for shoeing horses so I'd like to build a charcoal forge like in tim lively's video. He avoids electricity and uses the smaller of the handcranked blowers that I see on ebay for big $$$$. You post makes me wonder if a hair dryer work for a small charcoal forge? I don't see any reason why it would not.

George in Maine
 
Yes, just one forge at a time.
So a hair dryer puts out enough cfm? I suppose it is cheap enough to try.
I did not know dishwashers had blowers.
Thanks for all the replies. I will try with hair dryer. If that does not work, I guess I will save my pennies for the 112 model.
 
I saw one 1950 watt hair dryer that boasted of having an above average airflow for a hair dryer of 41 CFM so looks like they will be less than the 112 you are after. They might work well for the lively charcoal forge. I'd prefer one of the small hand cranked squirel cage blowers that tim lively uses in his video but judging by the inflated prices for them on ebay I have to assume they have become collectible Darnit :( They seem to be going for almost $150.00 now.
 
I've used bathroom exhaust fans as blowers for my forges since I started making knives 18 years ago. The first one I got was from a remodel job that I first used on my coal forge. I have since only used propane and I still used the same blowers. The first one was 50 CFM but I moved up to the 70 CFM that I went to mainly so I could forge weld. I paid around 30 bucks for the 70CFM at Home Depot. The thing I like best about these exhaust fan is they run very quiet unlike hair dryers or other more powerful blowers. Pretty simple to convert to. Here's a few pictures of my state of the art blower that I am still using today.

IMG_1967.JPG

IMG_1969.JPG

IMG_1973.JPG
 
I recommend 100CFM to 150CFM. A true forge blower has some differences in the blade shape and back pressure abilities, but most forges will run fine on any ebay or garage sale fan that has enough CFM.

The biggest difference between the two is that a $150 forge blower is made to run non-stop eight hours a day for many, many years. A bathroom fan is made to run one or two hour a day, and not for more than about ten-twenty minutes at a time. That is why you see fifty year old forge blowers for sale at near new cost price, and five year old bathroom fans at curbside on trash collection days.
Also, forge blowers are heavy steel and bronze,often with lubricable bearings, and can run in hot environments. They are also ready to install as a blower.
Bathroom fans are thin sheet metal, with plastic parts.....and made to be thrown away. They are not made to be in environments above 100F.They have to be jury rigged to use as a blower, often with some loss of efficiency.

As Raymond has shown, most folks use the cheaper fans, and change them when burned out. Nothing wrong with that.
 
If you YouTube it you will find some really talented Smiths
using bathroom fans with brake drums as forge setups.
Cheap and effective, about $20 for the fan.
 
bladsmth said:
I recommend 100CFM to 150CFM. A true forge blower has some differences in the blade shape and back pressure abilities, but most forges will run fine on any ebay or garage sale fan that has enough CFM.

As Raymond has shown, most folks use the cheaper fans, and change them when burned out. Nothing wrong with that.
Click to expand...

Stacy, I never have had one of my bathroom exhaust fans burn out. However they don't handle open flames very well. Anymore I seldom have the forge running more than an hour at a time. Got to give the forge a rest from time to time not to mention the old man that is using it. There's a real art in itself to jury rigging. Since I have been dealing with cows for the past 20 years I have become an expert jury rigger.
 
Yes, some of them run for years, and others burn out sooner. Your fan setup is proof that it works.....and can for a long time.

I purchased some surplus 120CFM/60CFM blower units from a medical surplus liquidator. They were two-speed, and had a heater in the nozzle. I removed the heater coils, took off all the limit switches and fail-safe devices, and had four really well built two-speed blowers for $20 each. They have a 2" ID output nozzle, designed to attach to 2" OD metal tubing.
These used to pop up on ebay regularly as they were being replaced with newer units.

Other good blowers that can be found cheap are the blower fans for oil or gas fired boilers and heating burners. Check your local heating contractor and he may give several to you. You only need a small one. any are way too big for a forge. Tell them 80-150CFM.
 
You can often find blowers on the top of scrapped out gas fired hot water heaters.

easy to take off and usually working.

Many appliance dealers have a pile of them stacked and ready to scrap out.
Especially small town appliance dealers.
they have much less pressure about keeping a clean yard than the urban centers.


I've gotten a couple free that way.
 
You must log in or register to reply here.
Back
Top