Sunday, April 29, 2012

Working the Press 2

 (slightly modified from the post on Bloom 2 Bar)
Something I saw at the  Corning Glass Museum (on the combined Smeltfest / Research trip in March).



F- 'Split Fire Riser'
R- 'Solar Riser LH4'
Thomas Patti - 1943
(Sorry - its a horrible image)

When I saw these glass objects by Patti at the Corning Glass Museum, I immediately thought of how the hydraulic press could alter the shape of a block of steel in a similar way.

So this is what became of the concept (Very, very, first renditions)



The left corner is the result of the very first experimenting with the press day I did with David Robertson. (David had consulted heavily with me on the construction of the press before this OAC project begain.)
The tool was originally produced for potential use with my small air hammer. I never use secondary tools that much with the air hammer, primarily because of the small die surface (as repeatedly mentioned, only 1 1/2 " wide by 4 " long). Although it is true that lack of practice is part of that problem! It has a slightly tapered shaft forged from 1 1/4 ' round stock, so the working end is roughly 1 inch diameter. The shaft length is roughly 3 inches, made of mild steel. The handle is piece of flat stock, wrapped around and MIG welded on the top surface, then ground flush.

The starting block was a piece of 1/2 thick by  roughly 2 inch square.
The resulting shape was made by setting the tool on the orange hot block, then driving it downwards. I used the full power of the press (to 3000 psi), primarily to see how far through I could push the tool.
As you can see, what happened is that the tool 'bottomed out' at about 3/16 thickness. At that point the metal below the tool had most of its heat pulled off through contact with the tool and bed of the press. The increasing pressure then simply started to bend the shaft itself.


Obviously not the way to go. Interesting potential however.


The second test , at the upper right, (done April 17) started with modifying a tool. This small (cheap) ball peen hammer had been used for a different impression test initially. Result was that the pressure collapsed the walls of the eye around the original wooden handle. First I used a drift to re-open the eye and straighten the bent head. The hammer face side was forged down to approximately the same shape and size as a standard 3/4 inch taper base candle.  Last I forged down a piece of solid 5/8 " round to fit, then drove that into the eye hot to seat it.
The starting block this time was a piece of 1 inch square, about three inches long.
First the hot block was collapsed downwards into itself. With a second heat, the tool was pressed down into the block.
One unexpected result was that the ball top end actually left an impression into the mild steel top flat plate die set in the press. Not good. 



But the finished object? Closer, but still not quite.


Both tool and object prototyping continues...




Thursday, April 26, 2012

WORKING the Hydraulic Press

['Mark Green' ,21 April 2012 - 02:56 PM' - Don Fogg's Blade Forum]

I hope all is well with you. Jesus told me you were setting up a log splitter press for bloom compaction.
I was just wondering if you have that going yet, and how it is working?

This is an edit of the reply I sent to Mark, as I expect some of the rest of you will be interested as well.

My purpose for building a hydraulic press was to allow me to work up a huge pile of iron blooms (from a decade of smelting!). I currently have a 50 lb home built air hammer, but the dies are only 1 1/2 x 4. Not near big enough to work a bloom on.

I had taken a lot of images while I was working up the hydraulic press. My intent was to put together an e-book (pamphlet) on the topic. Never got past the information collecting - at least for this year!

That being said, I did write some pieces seen earlier on this blog :

http://warehamforgeb...ulic-press.html

http://warehamforgeb...-continues.html

http://warehamforgeb...ulic-press.html


The overview is this:
I took a look at a couple of presses others had built. Both in person and via various web sites.
I'm not the 'machine' guy - but my friend David Robertson certainly is. Hydraulics represents a level of complexity (and potential disaster) that I was uncomfortable with.
I had looked at several layouts - single or double cylinder, cylinder on top or bottom, C or H frame.

Anyway, I had already bought a used hydraulic pump and electric combination, from a guy I do trust. Question was 'how much and how fast'. A long session at a local shop did not answer that. I considered buying some valves, hoses and a high pressure gauge to test this. Was going to cost me at least $100 for those parts - even more if I bought long enough lengths to incorporate into a functional press later.

David and I went back to his local TSC to get those parts. As we walked back to the parts section, we passed through a display of log splitters. The manager spotted us and asked 'Are you thinking about one of those? If so, have I got a deal for you..."
Turned out the Champion 30 ton was going on sale for 1/3 off starting the next day. That put the cost of a *pre-engineered* system (with self contained power) at only $1300. The unit was already designed to work in the horizontal position.

David went off to do the math. The cost of purchasing all the components (2 hp electric, cylinder, pump, valves, hoses) was going to be at least as much. I would have to build a frame in either case, the difference being that if I scratch built, that frame would need to be considerably heavier (enough to manage the full 30 ton thrust). The alternative was simply holding the existing machine up off the floor to working height.
Most importantly, I would not be *changing* any of the actual working machine.

The final design moves the gas engine from its original mount to the opposite side of the machine (to allow the operating controls of that to be accessable to the front side. This did require adding an extra 24 inch piece to two of the hoses, only one a high pressure line. I did this via a T mount, which allowed me to mount a high pressure gauge - which turns out to be very handy in opperation.

The biggest problem I had with the conversion was venting the exhaust from the gas engine.

In operation the actual pump and cylinder are very quiet. You do *not* get that shriek that Jesus's machine produces. Balance that against the noise coming from the 5 HP gas engine.
Given my shop layout, I could in fact add another 6 feet of hose to all the lines, and just mount the engine outside the shop altogether. I did not want to do that at first, as I was concerned about slowing the action time of the cylinder.

In use the machine is wonderful.
The ram moves 'about as fast as you would want' - with 2 inches clearance on any given piece of metal, to full compression (at 3000 psi on the gauge) takes about 5 seconds. Fast enough to preserve the heat, slow enough that you can stop it if things start to go off.
I can compress a piece of 1/2 thick by 2 inch down to 3/4 thick in a single shot. The maximum compression under the full 2 inch width of the rectangular block die is effectively down to about 3/8 thick. The full plate die I made up is roughly 5 x 7 inches (used for compacting blooms, or using smaller handled dies or tools).

The fiddliest part of the conversion was setting up a replacement ram head. I just replaced the existing log splitting head, which had a step diagonal to it. I had to figure out how to make for easily switching top dies. You can see the solution in the blog postings. This proved most certainly worth the extra trouble. With the slot and single pin system I worked up, I can swap a top die out in about 5 seconds.

If there is any major disadvantage (other than the noise) it is that the press has a C shaped frame. The maximum depth is about 6 inches, only a problem if I was to attempt working with plate.

With EVERYTHING included, my total cost to get the machine up and running was $2100 (CDN).
That included the block steel to make three dies , a large flat plate, a rectangular compression head and a heavy cutting head.

Images:
First is a view of the completed log splitter to hydraulic press conversion
Second are some of the test pieces worked up on my first session. The rectangular bar is 1/2 x 2 mild steel. All the compressions are single strokes.

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Sunday, April 22, 2012

"the people we were - the people we are"

 Check this post by Jim Wright at his Stonekettle Station :

http://www.stonekettle.com/2012/04/people-we-were-people-we-are.html

It side swiped me considerably. I thought it was going one way (and broke my heart) and then suddenly shifted gears and hit me from another direction.

We all have those ancient friends. The ones that for some reasons that truly defy any rational explanation have slipped out of contact. The ones who chance (as much as anything) throws you back together with.
And its like the time and distance have never existed.

To them (and you know who you are) I suggest this piece by Jim.
I suspect Jim is most certainly a kindred spirit, and would fill any empty place at our table well and effortlessly.

Over the years of my own life, I have always valued *consistency* far more than *agreement*. Anyone around me most certainly can hold differing opinions. My interest is most often held by those who disagree, especially those who can offer measured and passionate discussion. What I have never had patience for are those who are inconsistent. If I can figure out how you are going to twitch, usually I can work with you. 'Say what you mean and mean what you say' and you and I will be able to come to some accommodation.

Always remember 'what goes down, comes round'.
*Responsibility* is more important than *Rights*.
Make a choice, but do so with clear eyes, head up - and be prepared to pay the butcher's bill when it comes due.


Friday, April 20, 2012

Building a PRODUCTION Iron Smelting Furnace

(a duplicate of the post at Bloom to Bar)

Making a bloom requires an iron smelting furnace. I have built dozens over the years, most on the 'Norse Short Shaft' model. The work on the actual smelting end (creation of the iron blooms) has been a combination of a learning process extended into experimental archaeology. Furnaces are often purpose built to test a specific variable, and commonly only used one or two times.

I have decided to take the opportunity offered by the OAC project grant to build a more durable 'production' version furnace.

The first day's work consisted of gathering the available supplies and possible pieces, plus cleaning up and preparing the site. The furnace built for last year's 'slag pit' experiments was examined to see if it could be simply repaired. 

Damage to top of Fall 2011 furnace
The nature of recording the slag pit experiments had meant picking up and moving the furnace itself after each smelt. The furnace had been returned to a prepared base and covered over with a plastic drum for the winter. The combination of all that shifting, and the winter weather, had resulted in a fair amount of damage. This certainly could have been repaired, but I decided to build a brand new furnace.

There would be a number major elements used for the production furnace which should combine to greatly increased durability :
use of a copper tuyere 
base area built of fire brick
metal sheathing over the shaft
use of sand / horse manure / clay mix
Part way through construction, with measurements
One of the things kicking around the shop was an old metal trash barrel, with the bottom pretty much rusted out. It was roughly 60 cm tall and about 35 cm diameter at the small end. Almost exactly the same size as the exterior of a short shaft furnace. I decided to use this as a combination form and protective shell for the upper shaft. The base area would be built from a circle of dense fire brick, both for durability and stability.
Firebrick base as laid out
 The furnace was constructed on the shelf that makes up one edge of the Wareham smelting area. This places the bottom base of the furnace up about 25 cm above the working floor. To create a hard bottom and stable surface, a (broken) concrete paving slab was placed first. The furnace is being constructed with a large tap arch - large enough to allow for possible bottom extraction of the bloom (although my normal method is a top extraction). The location of the tuyere will be to the left hand side as seen above. The placement of the fire bricks on edge creates a heavy and flat surface for the shaft of the furnace to rest on. The circle of standard construction bricks defines the boarder between the furnace and the natural earth surface.
Brick layer with clay fill 

The first layer of clay was a mix of 50 / 50 rough sand and standard ball clay (mixes by volume). This was used as a mortar to fill the wedge shaped gaps between individual bricks. Next the space between the firebrick circle and the outer retaining bricks was filled. Finally a sloped shoulder was created from clay to the top of the fire brick layer. A full bag of clay was required here.



Next, the bottom of the metal barrel was cut out. A slot was cut on one side, roughly 7.5 x 7.5 cm. This would be the hole allowing for the insertion of the tuyere later. The measurement from the top of this hole to the top of the barrel was 40 cm. (When positioned, the angle of the tuyere will place its tip even lower, so there should be a good 50 cm of stack height.)


Dry measures for the clay mixture
The furnace walls were composed of a mixture of course sand, shredded dry horse manure and clay. The clay used was 'New Foundry' - a higher firing temperature clay (which I had gotten from Lee Sauder). The ratio is roughly 25 / 25 / 50. This is mixed dry by hand before the water is added. (I took considerable care to make sure the mixture was fairly stiff, particularly with the first layer.) The material was kneaded up to an even consistancey, then hand wedged into balls and left to stand for about an hour before applying. (Note that Lee recommends letting the clay stand overnight to even out the moisture content. Yes - I did rush this a bit!)
First wall layer applied (tap arch at bottom right)
The individual balls were broken in half, with the individual pieces blended in carefully as the walls were built up. The metal form allowed to exert good pressure, but still keeps the overall shape consistent (and under control!) The thickness of the walls was kept to roughly 6 cm at the bottom, thinning slightly to closer to 5 cm at the top. You can see how the interior diameter is matched to the ring of fire bricks.
Because the metal barrel tapers, the interior diameter of the furnace will taper slightly as well. This is actually ideal, as it moves the tuyere tip slightly off the direct line of ore falling inside the furnace. (We have seen this arrangement reduces the amount of slag that collects on the tuyere tip.)

I finished up a long working day just as the sun was getting close to the horizon and the black flies were starting to come out. Expect some images of the final construction, once the clay has had a couple of days to stiffen up and I mount the tuyere.


Thursday, April 19, 2012

' I wish *I* had made that'

May be one of the higher compliments one artisan blacksmith can say about someone else's work:


Randy McDaniel
Dragonfly Enterprises

Here's a railing I did. The request was for it to be different, artsy and Williamsburgy. I guessed the last word meant scrolls.
Oh, it's all solid bar.
It goes in concrete, in the ground about 3' for stability

Those descriptive notes pulled from Randy's Facebook offerings

The key to the physical aspects are the massive solid round bar (maybe 1 1/2 inch) used as the hand rail. Which then extends downwards into the ground a long way for the anchor. The elegance comes from the long taper that bar has been pulled out to - which makes the top spiral terminal.

I generally do not much like scroll work. In the hands of most, they are normally to mechanical and simplistic. Here however, Randy has extended each scroll element into a series of reducing reversal curves.

Wonderful...

Wednesday, April 18, 2012

Introduction to Blacksmithing - SEEKING STUDENTS

This weekend is the first of this years 'Introduction to Blacksmithing' courses.

I am seeking students for this 18 hour hands on program!

Friday Evening - 8 - 10 pm : Lecture on materals, terminology, historic overview and 'how to buy an anvil'
Saturday - 9 am - 5 pm : demonstrations and forge work
Sunday - 9 am - 5 pm : demonstrations and forge work

The program is limited to only FOUR students. Each will have their own fully equipped anvil work station, and share a forge with another student. Both propane gas and traditional coal forges will be in use.

This program will pack enough information and basic training to keep you busy on your own for months to come perfecting the skills!


The Wareham Forge is located north of Orangeville Ontario, just off Highway 10 (near Flesherton).
How to get here? See the directions sheet

If you are interested in this program - e-mail me : courses(at)warehamforge.ca

Monday, April 16, 2012

Demonstrating the Aristotle Furnace



This video clip was shot by one of the participants at my March 10 demonstration at the monthly meeting of the Ontario Artist Blacksmith's Association (OABA, through the work of editor Sean Stoughton, regularly posts video on to its own YouTube site. )
The sound quality is uneven, and as hand held footage is a bit jumpy. The beginning explaination is missing, but if you stick with the clip, you will mostly get the sense of how the small re-melting furnace works.

For more info, download a handout at: http://www.warehamforge.ca/ironsmelting/Aristotle-HO.pdf

An earlier description of this demonstration was made here on B2B : March 11 - the Aristotle Furnace

Friday, April 13, 2012

Forging

(This is a duplicate of today's post on Bloom 2 Bar)

Lee Sauder had this to say about his use of a copper tuyere:
1) The original inspiration to try the copper came from the Catalan furnace descriptions. I tried it the first time I tried the flue tile, after the first Early Iron at Cooperstown, so I guess that would have been late ‘04 or early ‘05. I have used them almost exclusively since, with the Coated Tyle furnaces, the Cadhinos, the big steel and refractory Aphrodite, and all the clay furnaces.
2) I have found that they will melt if they are much less than 14 inches long (this is with about 2.5 inches protruding into the furnace).
3) I looked back through my notes, I think I used the last tuyere for 45 smelts before I retired it, but I’m not sure. It didn’t fail, it was gradually thinning, and I didn’t trust it anymore.
I had made a first attempt to try out a copper tuyere for my own smelts # 7, #8, # 12 in 2005. My problem was at the time I did not have suitable copper material to work with. I had tried cutting and forming from 1/8 inch thick copper sheet. That thickness just was not enough to either withstand the furnace temperatures or transmit heat off fast enough to prevent erosion of the tip. Work with copper tuyeres was abandoned in favour of using a standardized ceramic tube (starting in 2006).

Last year at Quad State, I had picked up a large bar of copper, 2 x 1 1/2 x 12 inches. (Luckily, I paid less than current scrap prices = $20.) I had actually intended this material for an artistic forging project, but like many good intentions, the piece got tucked away and pretty much forgotten.

With the reminder caused by the slag rings recovered at Smeltfest this year, and wanting a break from the heavy forge work this week, I pulled that block out. The starting weight was 4358 gm.
The first step was to combine draw, widen and flatten the material to a rough flat bar. This was done under the air hammer - mainly 'pushing' the material under the dies. (Starting at the far end, and pushing the material back towards the tong end as the dies collapsed it.)
Copper is wonderful material forge! It is extremely soft at a dull red colour, and even when the temperature drops, it remains soft and workable. This softness also means less vibration shock back into your hands. The big problem is heating a large piece. Heating in the propane gas forge, I was never able to get it much more than a 'bright red'. The end of the material hanging out of the forge was radiating off heat almost as fast as the burners were applying it.


After the initial flattening
(sorry for poor image quality)

At the end of the first stage, I had a flat bar roughly 1/2 inch thick, 3 inches wide, and about 20 inches long. You can see most of the thickness had been transferred to length, working on the flat die on the air hammer. In the image you can see how I cut off the last 4 1/2 inches (955 gm) of material.

The remaining piece was forged to a taper, both in thickness and width, over its length. This was done in a number of steps. Initially the material was worked by placing it to 90 degrees to the long axis of the dies. Next the surface was worked under a Hoffi style crowning top die. This was followed by a fair amount of working the surface with the cross peen. Again the direction of the peening was done at 90 degrees to the long axis of the material. The net effect here (for the non blacksmiths) is to primarily force the material side to side - not end for end. Last, the surface was worked with the forging hammer to smooth out all the irregularities caused by using the peen on such soft material. At this point the edges were also hammered to create a more or less even and straight lines.

This all created a shape like a triangle with the tip cut off. To finish the work, the peen was again used, but now over a half cylinder shaped anvil tool. Also it proved just as easy to work into the hollow created by the step from horn to face on the right hand edge of the anvil. This series of more gentle strokes gradually formed the flat surface into a half curve. This was carefully rolled up to where the two edges met - creating a conical form.
This was then worked to ensure the shape was symmetrical, and straight.


Finished copper tuyere

The resulting tuyere is 45 cm long. Its finished weight is 3394 gm.


Furnace End
2.5 cm internal diameter
wall thickness 6 mm


Air Input End
5 cm total diameter (accepts standard 1 1/2 inch threaded pipe)
wall thickness 3 mm

Wednesday, April 11, 2012

Casting Demonstration at the ROM

Archaeology Weekend

Royal Ontario Museum

Bloor at Queen's Park - Toronto

Saturday, April 14 and Sunday April 15
Free with regular admission

Come and find out what archaeologists do to make their discoveries! Meet archaeologists showing things they’ve dug up and explaining why they are important. Get up close to objects usually hidden in the museum’s vaults. Try your hand at being an archaeologist as you learn some of the skills they use in the field and labs. Then meet people who do "experimental" archaeology by trying to do things the way they were done in the past, and "living history" re-enactors of the Viking era who try to understand the past by living it!

Pewter Casting
Canada Court (Level 1)
Watch the process of how pewter is cast in a traditional method.

Living History
(Third Floor Heritage Block, Level 3)

The Viking Age
Experience the Viking Age with the help of the Dark Ages Re-creation Company. See how people worked and lived, and displays of experimental archaeology where people figure out how things found in the archaeological record were made and used.

DARC's presentation will include:

Iron Smelting - experimental archaeology, passive display
Glass Bead Making - experimental archaeology, passive display
Cloth to Clothing - experimental archaeology, passive display.
Tablet Weaving - living history / craft presentation
Domestic Life - living history / 'sea chest'
Sheep to Shawl (Warp Weighted Loom) - living history / craft presentation

See the rest of the programming available on the ROM web site


My personal piece of this (besides organizing and logistics) is the highlighted Metal Casting presentation.

See you there?

Tuesday, April 10, 2012

Slag Tuyere Rings

(for any archaeologists reading)

These are some shots of slag rings recovered from two of our recent smelts (at Smeltfest 2012, Lexington VA, March 2012)

Lee Sauder has been using a heavy forged copper tuyere on all his smelts for the last several years. The tuyere was forged from a plate roughly 3/8 inch thick. First the piece was cross peened along the long axis to both spread and thin the rectangle into a triangle shape. Then the resulting form was wrapped into a cone. The finished cone is roughly 2 cm ID on the furnace end, about 4 cm ID on the bellows end. The piece is maybe about 40 cm long altogether.

In use, what happens is that the heat the tuyere end is subjected to quickly travels back to the larger end exposed outside the furnace. The combination of radiation to the outside air, and rushing cold air down the inside surface, all combines to keep the tuyere end well before the slumping or melting point of the copper material. The result is virtually no effect to the the copper tuyere, even after many firing sequences. I think Lee has used this same tuyere for something like 30 smelts, with no damage at all!


As the rings would sit against the furnace wall


Inverted, showing the slag and ore fragments on the top surface

The slag will harden to a shell around the tip of the tuyere. These rings do not solidly attach fuse to the copper, normally hand pressure will break them clear.
You can see that both the internal and external diameters are indicated in the slag rings.
You can determine the upper and lower surfaces, with the heavier accumulation on the 'up' side of the tuyere in the furnace.
You can get some estimate of the tuyere angle. The slag has formed proud of the furnace wall, so if you assume the inner wall to be vertical, the inside surface does record the tuyere angle.


Inner surface (inverted here)
The inner diameter and thickness of tuyere can be determined.

Both the rings show cracking in roughly the same place. I think this is an effect of the cooling rate of the slag and the shape of the rings. One of the collected rings had in fact separated into two pieces ( the ring on the left in the images above).

One ring was broken into two pieces

We have worked with ceramic tube tuyeres as standard here for the last while. These are uniform, cheap and fairly durable. They also are quite obvious as a physical remain. Same goes for the iron (steel pipe) tubes we have also made use of. As the iron tuyeres are consumed with every smelt, I don't think that this material likely for VA process - just from a practical standpoint. (wasting iron to make iron?)

Copper tuyeres might be another mater. They would be 'relatively expensive' as objects, but because of their proven durability would be worth the investment for repeated smelt operations. The copper would be too valuable to discard, likely just being cut up as raw material for bronze production at the end of their smelting use. Any finds of copper cut to rings as a bronze related find? It would be the easy way to re-cycle the material.

Anyway, the slag rings are quite distinctive. Lee said he gets these every time. Worth a check against remains?? (Kevin Smith had mentioned that he had recovered some semi circular slag fragments from his excavation of an 'industrial' VA iron smelting site at Hals in Iceland. It will be interesting to see if these modern pieces in any way resemble his artifacts.)

We messed with using a copper tuyere a long while back, but at the time I did not have any heavy copper bar or sheet. The copper tuyere I made up was only 1/8 thick material, and did not transmit heat fast enough to keep the end from melting back to the furnace wall. This would have certainly produced some droplets of copper into the slag someplace. Perhaps another signature to look for in the archaeology?

Sunday, April 08, 2012

and now, for something completely different...

The blacksmith and popular music.

(this is one of those posts that started one place, then ended up someplace else)

We watch Glee here in Wareham.
We both really like it. It is one of the best pieces of television out there right now. The actors are all extremely talented, most the time the writers have half a brain. Other than a few too many (obscure to me) broadway show tunes, I think they have generally done a lot of amazing covers of popular music.

Vandy had sent me a link to the video of 2cellos doing their version of Jackson's 'Smooth Criminal'. Very, very cool. Those guys have amazing energy. Get it on to the iPod.

Two weeks later, who do we see on Glee? Wazzah - its the 2cellos guys, with a vocal over top in typical Glee style. If you missed that, this is what it sounds like :



So, I thought, what the heck, lets look for some MP3 versions I can download for the ipod..
Which brought me to this version, by relatively unknown Alien Ant Farm :



Boy have those guys got energy!
And if you are familiar with Michael Jackson's videos, the Alien Ant Farm *video* is amazing. So tongue in cheek! (And love him or hate him, there is no doubt if there ever was anyone who deserved to be parodied, it is Michael Jackson. Ask Weird Al...)

Ok, Lets take a listen to Mikie's original version :



As a piece of music on the ipod, I've got to admit I do lean to the raw energy of the Alien Ant Farm version. I feel I get a two-for-one on the Glee version, however, with 2Chellos in the back.


So what is the point here?
I've got all four versions on my ipod. Not exactly sure why, but on random mode, half the time if it plays even one of those four versions - it will play all four in sequence.

There I was in the shop yesterday, ipod jacked into the shop stereo, working away on the latest bloom to bar sequence. Task was taking a larger piece (starting at 1.5 kg ) and working it down into a thin plate. I've gone past the hydraulic press stage, past the air hammer stage, now working with the 1 kg crowning hammer to thin and spread the plate.

Now, those who have seen me work know that I have a distinctive style. I use a physical dynamic that allows me to use speed - rather than power. More strokes per minute, lighter hammer.

So - there I am, wacking away at this bloom plate.

2cellows or Glee + 2cellos = great to listen too, but way too fast for me to pound to (or too slow at one stroke per beat)

Alien Ant Farm = pretty close, but still just a hair fast for me, especially into the end of the second hour taking welding heats on a 1.5 kg mass.

Jackson?
Perfect.
Double up on the main beat structure (so every second hammer stroke falls on the percussion)
Go listen to that version again.

Ah, Michael, if you only knew...

Friday, April 06, 2012

A typical OAC project day...

I started with this:


And ended up with this:


For the full photo essay, check over on today's Bloom to Bar posting

Wednesday, April 04, 2012

Exhausted by Exhaust - Hydaulic Press (continues)

(Duplicated from Bloom to Bar)

Its NEVER as simple as it seems...
A saga of poor design and failed materials

Day 47

In my original proposal, I had included two weeks for shop conversion and preparation directly for this project. Along with laying out the space to dedicate it to project work, I had included some time specifically to finish setting up the hydraulic forging press. (I had purchased and started working on the building the press over two weeks before I even knew I had been awarded the grant.)
You know what they say about grand plans and good intentions...

The 30 ton hydraulic forging press is critical to the bloom to bar work. As I have mentioned before, my 50 lb air hammer is simply too small, both power and die size, to work the blooms. This is especially true of the larger ones, in the 7 - 8 kg range. These masses are roughly the size of half a basket ball. Imagine attempting to balance, and compress that, on a die surface only 1 1/2 by 4 inches.

One of the major problems I have encountered with installing the hydraulic press is with the engine exhaust. The press uses a 5 hp gasoline engine to drive the hydraulic pump. The way I re-worked the original log splitter equipment into a forging press places the engine exhaust such that it would end up blowing straight on to the operator. Hardly ideal.
The solution was to install a system of piping that would both contain and vent off the exhaust completely outside the building.
Which has proved far more difficult that I expected.

Exhaust System, mark 4

The problem has been two fold:
1) Leaking fumes from the various joints between fittings
2) Vibration from the gas engine

My initial idea to combat leaks was to eliminate / reduce the number of joints, and tape over all the joints. I normally use a thin aluminum tape, designed for heating duct work, around the smelting furnaces. The aluminum has a quite high melting point, and easily crimps over irregular surface.
The problem with the tape is that the resin based adhesive burns off at the kind of temperatures that the hot engine exhaust produces. Especially close to the exhaust port - which also happens to be the place most of the pieces are stuck together.
(The engine port is roughly 1 1/4 diameter. I've modified the original cover with a short piece of pipe. Next I made up an aluminum conical fitting that expands out to 3 inches. To that is attached commercial fittings : a 3 inch adjustable elbow, a short section of 4 inch duct pipe, then a 4 inch adjustable elbow. All have joints to secure.)
So the first tape job lasted about 15 minutes.
I pulled off this tape, re-applied fresh stuff. I wound a length of thin wire over the whole section, bracing over all the joint segments. Then I put another layer of tape over the wire.
That tape job lasted about a hour.

On the end of the elbow, I had placed a length of flexible aluminum hosing, normally used for clothes dryer vents. Although this material was a bit thinner than I would have liked, it also came as a single 20 foot length. I could run the end right out the shop door.
Too flexible and too fragile - the vibration tore up this hosing about an hour into the press operation.

I was getting pretty frustrated at this point. I'd spent much more time on fixing the venting than doing forge work. I decided to give up and head into town. Brent at my local McDonalds Home Hardware (in Dundalk) suggested a fiberglass repair tape intended for fixing mufflers. "How good does this stuff stick" says I. "I used it one time for an emergency road repair, then had to cut the pipe off because I never could remove the stuff." says Brent. "But its expensive..." Like $4 for 36 inches. He has one package, which I buy, and tell him to order me another (which turned out to have been smart).
I also get a different type of expandable aluminum dryer hose, this less flexible and considerably heavier weight. This is the stuff I use on my forge blowers in the shop. It is twice as expensive, and only half as long.

Next day, I pull off the round two tape, lay down one layer of new aluminum, re-bind the wire over it. Did I mention that this fiberglass stuff needs heat to set and cure it? So I have to turn the engine on, breathing exhaust and trying not to burn my fingers. I cut and set the repair tape. Of course when it is warm, the damn stuff slides all over the place. I lay down another layer of aluminum tape to hold the fiberglass in place until it cures. Turn off the engine, attach the heavier semi-flexible hose. Now wait for the fiberglass to cool and set.

This was all the week of March 5 - 9. By that point I was supposed to be focused on bloom forging - not equipment. I had scheduled a workshop day with blacksmiths Kelly Probyn-Smith and David Robertson for Thursday March 8. Kelly had to cancel on short notice. David did come over, and we spent about four hours (a long work session for forge work!) experimenting with the hydraulic press.
Only to find that although the fiberglass tape held well, the hosing did not. Two tears in it, both from the vibration.

At that point I had the OABA demonstration to prepare on Friday, the demo of the Aristotle furnace to mount Saturday. I was leaving for the combined Smeltfest and research trip on Tuesday crack o dawn. I had not done any serious trip planning or any packing for that either.

Press Venting - complete

(Leaving out the two days spent figuring out why the brand new engine will not start. Read as 'water in the gas, stupid')

So on the way home from Smeltfest, I stop at the Shelburne Home Hardware, and get more elbows, several lengths of heat vent pipe. (No, I do not have measurements)
I get 'serious' on the vent installation. More fiberglass tape on all the joints right at the press. All joints secured by screws. All joints in the whole system taped with aluminum. Solid pipe throughout. Pipe is supported on bungee cords to dampen vibration.
Add another day because I'm short on the pipe required.
Add two days (one for snow, one for rain) because I have to climb up on the roof to fit the vent cover through the upper shop wall.

You can see the finished system runs the exhaust up the side of the press, then over to the shop wall. Over the top of the lower section (12 inches of concrete) to the upper wooden and metal sheeting covered portion. There is a standard dryer vent that now exhausts (most all) the fumes to the outside. And some of the noise too.

Total time expended : better part of a week's work sessions.
Total additional cost : over $100


Movable base plates for the press

Yesterday, along with some very good bloom forge work (report to come) I made up a pair of extra base plates for the press. I just happened to have a piece of 1 x 6 plate in the shop. It proved just long enough to make three individual base plate pieces. The largest covers pretty much the entire press base, serving to raise the work surface up an extra inch. The smaller pieces fit nicely under the flat die I had already made for the press head. These two new base plates both have flanges on their edges (not clearly visible here) which solves the vibration problem I was having with pieces just set on the press base frame.
The bottom edge of the tape seen on the right side of the frame indicates the location of this flat plate die with the ram at full extension. You can see that with the two new base plates in place, the flat die will actually come to contact before the ram is at full extension (remember that there would be a piece of hot metal in there too.)

Monday, April 02, 2012

Lord Thunderin Jesus...


From 'Hark, a Vagrant' - by
Kate Beaton



(Image should load directly from Kate's site - if not, click here)

This is twice as funny if you have been to the Norse Encampment presentation at L'Anse aux Meadows NHSC.



Four times as funny if you actually know Mike Sextant, who portrays 'Bjorn the Beautiful' as one of the staff interpreters.

(Image of 'Bjorn' is from Parks Canada)
 

February 15 - May 15, 2012 : Supported by a Crafts Projects - Creation and Development Grant

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