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Hate asking this/ scale removal


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I hate asking this because i feel like it is such a newb question but how do you get your metal to look good after you get done forgeing it. On mine i still have scale stuck on there and scale markes. also its molted colors of grey, silver, and black. i also have a ton of unnecasary hammer dents, i try take them out with a light hammer but it dosent do as good as i would like to. if i could get some help it would be great.

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There are a few tricks and skills at work to getting a nice finish.

First is forging skill, the fewer times the work has to go to the fire the less scale it'll build up. This also addresses the hammer marks and or lack of.

Anvil height can have a lot to do with excessive hammer marking, if it's too high or too low you have to consciously TRY to make the hammer face strike parallel with the anvil face. Set your anvil between wrist and knuckle height and your hammer will naturally strike flush.

The more naturally the hammer strikes correctly the less skill it takes to make it do the right thing.

Scale. Find a "butcher block brush" they are flat wire brushes that are efficient scale removers. Brush while the steel is good and hot, start at low orange and put yer back into it till it's cooled to the point you want to apply wax, say 350f +/-. Most blacksmith suppliers carry them.

Proper fire management can be a factor, placing the iron too low in a solid fuel forge will result in exposing it to excess oxy at high heat which is a scale generating demon. A propane forge running too lean has the same result.

Another way to remove scale, you're almost always going to have scale form, is an acid bath. White vinegar is slow but works well for removing scale. Muriatic acid works just as well and a whole LOT faster but you have to consider proper handling and disposal of a HAZMAT.

A tumbler is a good way to clean up the work as well though they tend to be beastly noisy things. Still, if you have a lot of pieces to clean they're hard to beat.

Sand blasting works well.

A rather messy but effective way to keep scale from forming at all is to flux the work and keep it fluxed. It works but it's really messy and I personally don't care for hot borax burns myself.

I'm sure there are things I haven't thought of or am simply forgetting to put down but those are some basics.


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Most people use a wire brush for cleaning off loose scale or a powered wire brush for more aggressive cleaning of the scale for general purposes. Of course if you want to remove all scale and colours you can sand blast the piece or pickle it with acid. Knife makers of course spend a LOT of time filing, grinding, polishing and buffing their products for the bright finishes obtained ( not to mention etching to bring out the patterns.
Grinding flat surfaces is the easiest way to remove hammer marks, but learning good hammer control goes a long way toward rducing the amount and severity of the marks left behind in the first place. Others will offer suggestions here as well I'm sure.

Just remember one thing though, there is no such thing as a dumb question. We all stated out not knowing anything either. It is through experience, trial and error and asking LOTS of questions is how we got to were we are today.


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I might also add that keeping the anvil face clean is important. I will refer to coal for the moment ( and a crank blower ).

Place the stock in the fire level with the near edge of the firepot ( no lower, meaning having stock tilted downward into the fire ). If heating longer area, place stock through fire until you feel far edge of the pot. Keep cover over the stock and fire under. Some coal will lose the bottom pretty quick ( meaning that the coke in the pot burns faster than the replenishment coke on sides and top ). You might slow down on the blast and keep a more insulated deep top ( larger mound). We all get impatient. Coal fires will change really pretty quick. I have some good coal in a barrel that I save for specific needs. That particular coal is Sewell Seam coal and really hard to come by around here. I have stock coal that I can get. I use it or charcoal for normal day to day stuff ( solid fuel ). The stock coal will yes lose the bottom fairly quickly.

This means that when I build the fire with yesterdays coke ( or charcoal ) and I add forge shovels of wet coal to the sides and rear I have a mound of coking coal in a reasonably short time. Slowly rake the green wet coal over the top to create an oven of sorts. Adding small amounts of water to that pile and keeping the pile packed lightly with the shovel will maintain a pretty good fire for the moment. Forge a few pieces with sufficient coke under the stock using a light to moderate blast. Notice the green coal on the edges and keep that green coal raked on top and up the sides. Keep the top and rear tamped down and green from the edges or sides raked over when you see flames coming out. SMALL amounts of water sprinkled on these areas on the green coal. This helps to coke and insulate the outer area. You may or may not notice by now ( through the front opening in the fire ) that the inner fire above the blast hole has burned a lot of the coke out and you have a hollow spot. You can forge in this area, yes. You will also notice large amounts of scale. Coal is different, period.

One method of fixing the above problem is to add coked coal through the hole in the front. This coke can be off the forge table or from a bucket that you may use when you clean the forge table. I will clean the table from time to time ( cold forge, no fire ). I keep an ash bucket under the cleanout. Just place a piece of 1/2" mesh hardware cloth ( rat wire ) on top of the ash bucket and shovel a couple onto that wire. Lightly shake the wire. Ash and really small stuff into the trash. Pick through the remainder ( clinkers etc ) and dump into the other bucket. I normally use steel buckets for the coke collecting. Continue until the forge is clean ( inc firepot). I have a small brush that I sweep the area inside the forge to rid of ash. You can also use the same method to police the area around the forge ( sweep the floor, dump onto the wire, pick through and collect in coke bucket).

Unpredictable coal. You may also find that from time to time the stock isn't heating but you yes have a fire under it. You MAY find that the fire under is a spongy mass that holds together kinda like peat moss or manure and straw in a barn. Just remove this mass with a clinker tong or drag it out onto a shovel and dump into the ash bucket. Now you remember why you don't put flammables in the ash bucket.

Another method of contracting the bottom of the fire burning out is to smack the edges of the fire ( and top ) with the shovel. This will pack the fire into the pot and the coked coal will replenish the fire. add green coal and lightly water as needed. Coal can be had locally in the state. It is labeled "Premium Blacksmiths Coal". It is sold commercially. This is extremely unpredictable stuff but it heats for the most part. You WILL see strange things ( barely red fire from time to time, wierd little blue flame edges from time to time). Some get along with it fine they say. I will not say whom the distributor is nor the brand of coal. This problem led me to use commercial charcoal and also to finally build the gassers a few years ago. I wish to thank the folks here ( although most no longer post) for the advice on the gassers. I also wish to thank Jens Butler for the continuing education on the charcoal. I had some expereince but he helped me along.

Sometimes a light tap with a hammer will knock fair amount of scale loose. Sometimes a re-heat in a proper area of the fire and tap or brush will remove scale. Keep the anvil face clean. Use the butcher brush. I buy wire brushes 1/2 dozen at a time from an auto parts store ( STEEL bristles ). They end up about a buck apiece.

Measure your inseam. Try this for anvil height. Extend your arm(relaxed) with a hammer in your hand. Now, place the hammer head on the anvil ( or a table or the tailgate of the truck or whatever ). Get this measurement and try it. If you think your anvil is too high, step up on a piece of lumber ( scrap 2x6 or piece of bridge plank).

Find the place where your hammer face is flat on the anvil face. I MUCH prefer a slightly radiused hammer face over a flat face with radiused edges. I have spalled the edges of good hammers. To each his own on the hammer disclipine. I like longer shaved handles with a bit heavier heads. Mr Hofi and myself will have to agree to disagree. :) He is more than an extremely talented man, he is a legend. I tip my hat to him in extreme respect. His years of experience are appreciated in his postings here. We just swing a hammer a bit differently.

One more thing I have learned and then I will quit. The thing I have learned is from an old original book that was gifted to me by Greg Scheumaker. It was his Grandfathers. The book is "Practical Blacksmithing" by Holdstrom. One quote stands out:

" Saving coal to a fire is like saving grub to an apprentice or feed to a horse. Neither will give you a days work if they don't have all they want to eat ".

Long winded but thats my story and I'm stickin to it. At -3

Edited by Ten Hammers
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Check that your anvil is level. The reason I say that is based on an experience I had this past summer. I was doing a demo and just about everything I hit had hammer marks in it like I never saw before. No matter what hammer I used, my work was not up to par. I struggled along the whole day doing the best I could under the circumstances. As soon as I got home I put my anvil back in place in the shop and fired up my forge. (I left my other forge at the demo place because I was returning in a few weeks for another demo). When I started hammering, no hammer marks. ???????? I started thinking about this and what could have been the problem. The next time I went to the demo, I took a level along. Guess what, where I was setup the anvil had a slight tilt not visible with the naked eye. I moved some dirt around until I got the bubble dead center. Started to hammer and didn't have the hammer marks like before.

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Scale removal: I have a short piece of 4x4 angle mounted right by the forges and each hammer. There is a pair of butcher block wire brushes screwed into the inside of the angle iron making a trough of wire bristles. Drag the hot iron piece through the trough as you pull it out of the fire and before you put it back in. The brush mounted by the hammer allows you to take a quick swipe as the stock is worked.

A quick scrape with an old coarse file works well at red to clean up on the finishing heats.

Hitting the bar hard on the edge instead of the face works best to get rid of the mill scale on the first heat, then you aren't having to fight the heavy mill scale through subsequent operations.

Keep a horse hair brush handy to keep the dies and anvil clean. An air hose with a long nozzle is handy to keep fixed clapper dies clean, but watch out for hot drops and high pressure air hoses.

Any scale left on the finished work can be blown off with an OA torch. Use a big [#2] cutting tip with a neutral or slightly oxidizing flame with plenty of pressure . A quick pass over the cold surface will pop the tight scale right off. If a second pass is needed allow the steel to cool completely before hitting it again with the torch.

Pickling with an acid can lead to rusting problems down the line if the acid is not completely neutralized, rinsed and dried and is limited to the size of the pickling bath.

I personally don't like the surface quality of work that is heavily wire brushed with hand or stationary power tools.

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Dewalt grinder with either a cup brush or standard wire wheel. Also Walter makes these great flapdisks for grinders, sanding disks and grinding disks and wire wheels.

I use a big pickling bathtoo , holds 35 gallons, and I'm gonna build a bigger tank. Got a five gallon size tumbler, but am in the process of making a 100 gallon size.

Also have a sandblaster and a blast cabinet. All depends on the project.

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I'm always always removing scale since I make tools and fabricate weld and forge. The two things i've used the most over the years are abrasives and wire wheels. Now I have not yet used a large hopper with media blasting but I'd love to some day. This is how the pros usually do their cleaning and prep work prior to painting. They used to use glass beads, now I believe they use a talc and even fine ground walnut shells in some cases. In any case it leaves a nice matte finish on your metal.

Now sanding will leave a brighter finish, and wire wheels will leave almost a brushed shiney to matte finish depending on if your wheel is course or fine.

So for sanding I use a right angle pnuematic die grinder with 1-2" type roloc abrasive discs in it. You will see these around tons of shops. They work great for small tight areas.

For larger areas or thicker scale you can use various abrasive discs in your angle grinder. You can start with grinding discs and then move up through the sand paper type discs from lowes/depot (they are cheap 1.50$ or so a piece) pretty cheap.

They also make very tough abrasive wheels for your right angle grinder http://www.mig-welding.co.uk/paint-stripping/clean&strip.jpg for stripping.

Now if your not using a pneumatic or electric grinder the wire wheel is the other thing I use, virtually all the time. dewalt-WireWheelCrimp.jpg
and these go on bench grinders/buffers and you can get them in fine and course steel and in fine and course brass. They work excellently. Just hold your part well so it doesn't catch and wear safety goggles cause sometimes it will throw little wires around at high speed. I use wire wheels on my jet buffer. 31Y3QCGCS5L._SL500_AA280_.jpg

Of course any of these products will also work..


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