Mark Aspery

Sorry no photographs...
Take a 24inch length of 1 inch by 3/8 thick bar and draw one one down (not correcting for growth in width until it is about 2 inches wide by whatever thick at the end. Extend this taper back about 6 inches.

Place the stock on edge and knock the spread material off to one side of the bar. That is one side will be straight and one side will flare for the last 6 inches or so.

If you are right handed, you will probably want to work off the right hand side of the jig. That being the case, place the flared side to your LEFT as you scroll the bar over the rounded edge of the anvil to start.

Proceed as per making a scroll, checking your jig against your chalk drawing on a bit of rusty tin plate (or paper drawing soaking wet on a metal top)

Once you have the first few inches scroll, stop and clean up the outer surface. By that I mean get rid of the lipping and cupping as it will effect all your other scrolls.

Scroll some more and do a little more clean up.

Take your time - this is the mother of all scrolls - it had better be right.

Weld a short section of angle iron across the bottom when you have finished and it will hold in the vice.

You can use thinner stock, but it will kink a lot easier as you scroll causing sharp intakes of breath and much gnashing of the teeth.

140lb is what im looking at - do you like yours? and why?

30mm or 1 1/4 inch hardy on quite a few models.
I have 140lb Brooks anvil (pre Vaughns I think)

I take Sam's position - the gap is common place - and for good reason.

When you weld a collar onto a bar (which in essence is what you are doing) there has to be a gap between the ends in order for the collar to close on the material and weld.


No gap, no weld!!!!

Mark, how did you make the bolster plate?

I make a bolster plate the same size as my hardy hole and after tapering the end of a bit of square bar, upset it into the bolster plate, dressing the sides as I go.

This will leave you with a blank bottom swage. I make my bottom fullers the same way, but from rectangular stock.

Sometimes I have difficulty making them square!

A lot of the nautical stuff is related to astronomy.
The 'Dog' days of summer referred to a particular star that could be seen at that time of year.

I have a couple of ways of dealing with this problem.

1.) cut the end of the bar to the desired angle, drill and insert a piece of round bar. Either thread the hole and round bar or plug weld.

2.) If you are looking for a more 'traditional' approach I have two methods

-Form your normal tenon on the end of the bar, but with shoulders on three sides of the tenon only. One side of the tenon is level with one side of the bar.

Take another bar with a hole the same size as the tenon and hold it so that the bar is on the same side as the longest shoulder. Hit the bar while lowering you hand. This will cause the bar to upset on the long shoulder side and drag the tenon along with it.

- When cutting for the tenon, place the cuts in the position that you want the eventual shoulder of the tenon to be.
Draw down the tenon holding it flat for the sides and at an angle for the top and bottom. I find it useful to place the bottom cut edge on the side of the anvil, hold the bar at an angle and drive in the top corner. This sets the mass in the angled direction.

I'm sorry, but I don't have any photos of this. It may take me a few days to come up with some.

rakessler, a "monkey tool" is really nothing more than just a stick, sometimes a mere blade of grass.
Monkees are smart and a long time ago one of 'em figured out if you shove a stick into a hole in a termite mound and then pull it back out it is covered with termites and you can lick 'em of and then go back for more.
Now, not ALL monkeys is that smart, some of 'em gets it and some don't.
Some of 'em watch and watch and just get irate and start to flingin' stuff around but don't get with the learnin' curve and get their own stick...

Here are some examples of a couple of tenons and some shots of a monkey tool.

You will note that one of the tenons has an offset shoulder to it. That shoulder will rest (usually) below the tenon to offer support to the bar by trying to stop it from sagging.

I think the term 'traditional joinery' really should be termed 'period joinery' - but that's semantics.

There are a number of ways that a blacksmith can join multiple pieces together. Rivets, welding, tenons and mechanical to name a few.

Of those, some joinery is purely for the connection, others are for the connection and to counter the forces of tension and compression (Sag in a gate for example)

The shoulder of a tenon should fit flush against the piece that it is inserted into. To get that clean shoulder, a monkey tool (a bar with an appropriately sized hole in it) is driven over the tenon and onto the tenon's shoulder - thus dressing the shoulder for a good fit.

'Traditional' joinery can be anything from crude tapers driven into a hole in another bar and headed over to much more complex arrangements.

I think it can be viewed as a skill, a science and an art form - verging on to a quest like status for some.

Buckle up, it can be a bumpy road... but one worth going down.

Here's my .02 - I'm sure there will be a lot more from some of the other smiths.

1.) Never fuller to the full depth that you require when you butcher to isolate the mass to draw out for a tenon. You can draw the cut down a little into the tenon in the drawing out. This will cause the tenon to fail later

2.) Always create a slight shoulder to a tenon rather than a 90 degree transition. Cracks appear from 90 degree transitions - usually after riveting the tenon in place!

3.) Chamfer the edges of the hole in your monkey tool (see above)

4.) chamfer the edges of the hole that your tenon will fit into

5.) The edges of your butcher should be round not sharp - see point 2

If you are going to use a socket set or other manufactured tool to act as a monkey tool, please make sure they are devoid of any chrome plating.
The chrome comes off quite easily and is very sharp. If it comes off while hammering, it has a lot of energy and can travel some distance.

Non chromed impact wrenches can be use for square tenon shoulders.

I think it is better to make monkey tools yourself yourself -- as a blacksmith!


So how did the monkey tool get its name?

Your local coal merchant should be able to supply you with blacksmith coke. It's generally the size of the top portion of your thumb. Somewhat flame proof to start, but it will last longer than charcoal - attracting less attention from your neighbours.

Take a look at the British Artist Blacksmith Association (BABA) web site. There are quite a few educational opportunities for you in the S/W UK.

Where abouts are you located?

As always, a simple and very clear lesson! I'm curious how you went from step 2 to step 3 of the heel tenon... I can't figure out a simple way to make it offset...

OK, my .02. A couple of things. First notice that both of the butchering tools that Mark shows in the picture have a radiused edge on them. Second, and I know it's there even though you can't tell from the picture. When you make your monkey tool, chamfer the mouth of the hole that tenon goes through. Just a bit. You can do it with a bob punch, or with a countersink in a drill. You don't want a sharp corner here either. A couple of other things to think about. Are you working the steel too cold? Are you getting the work done on the tenon with as few heats as possible? Overworking the steel and working it too cold are both sure ways to propogate cold shuts/cracks especially at a square corner (which is why you want a radius on your butcher and a chamfer/radius on your monkey tool).

I'm a big fan of the method Mark showed. However, if in spite of all you do, you still end up with the beginnings of a cold shut, stop and rasp it out.


Question for Mark: Do you ever use a side set? Perhaps with larger tenons or do you feel the step is unnecessary.

Generally when I have this happening to me, it is because I have made a mistake when I was butchering the material - isolating the mass for the tenon.

As I travel a lot to smith, I take a butcher edged hand chisel for my tenons. If I could have my preference, I would take a butcher edged hardy cut-off tool.

I know that the closest that I can work to the end of the stock is half its thickness from the end. If I work any closer than that I will peel off the end rather than butcher the material.

I forge out the tenon using a guillotine tool made from 1 1/4 inch square tubing with some 1 inch bar inside.

This can be two bits of the tubing welded to a piece of angle iron that will fit into your hardy hole.

The shoulder (only) is finished with a monkey tool.

There are many formulae. All about as good as each other.
I'll throw in my $0.02 and it is as good as the rest.

There is no silver bullet for anvil height. As soon as you reach for a top tool or use a hand tool, your anvil is not at the correct height anymore.

For me, I take my normal hand hammer - the hammer that is in my hand for most of the day and place that on top of my average stock forged on the face -as if I were forging it. For me that equates to about 1/2 inch bar.

I want to look at my hammer arm. Is it hyper-extended or is it too bent. I want a slight bend or break to my hammer arm at the moment of impact and set the anvil height accordingly.

I also hold a lot of stock between my legs when I am working with a top or hand tool. This means that the anvil height cannot be higher than my inseam with boots on -or I run the risk of.... well hurting my 'other' hand let's say!

Upsetting - stabilizing the bar end.

The end of a bar can be stabilized somewhat, prior to upsetting, by drawing a two sided taper to its end. This will increase the dimension in the other plane (usually the thickness).

I have shown this twice below, once with a short upset and again with a longer upset for a heel tenon.

The taper allows the bar to upset without having to correct far a growth in width during upsetting as well as helping the bar resist the urge to bend and warp during the upset.

The first progression shows the finished upset where no blows on the side were needed save for a little chamfering. This can be quite useful to a smith as it can prevent the local upset of the sides (causing the lipping and cupping) that can be associated with corrections at the end of a heat on a large bar.

How about you turn your rivet around and pass it through the blower lever first. Then slide your wooden handle on -then add a small washer and then cold pien the rivet head over. It does not have to be the perfect rivet, just enough to stop the washer from coming off.

Hi. I remember looking at a blueprint for an upset helper. I don't seem to be able to find it now. Recently, I was over at a friend's house helping him make a rose. All I had was 5/16" stock, and this required quite a bit of upsetting to get it up to 5/8" for a smallish rose. Really, 3/4" might be better. Anyway, I recently attended an upsetting clinic, which was very helpful. I learned a lot. The instructor said "get it hot, hit it hard...NOT!". It is more important to have the heat localized, than to have it hot. And, it is better to hit accurately than hit hard. Either excessive heat or hard hitting will cause more bending and correction than it's worth. He emphasized the importance of "dancing the tip, and feeling the sting." In other words, let the hot end find its center by allowing it to bob up and down, and concentrate on feeling when the blow travels directly through the center of the rod to the chamfered tip on the anvil. Even with this instruction, which helped a lot, 5/16" to a 5/8" bulb is painstaking.

Is there a good tool design that can make this job a bit easier? I cannot quite remember what the upset helper was, maybe a block with a hole?

Ideally, H13 should be heated to 1600F and held for a minimum of 1 hour per inch, then cooled to 1000F at a rate no faster than 50F per hour (12 hours). After that is can be cooled more rapidly without an increase in hardness. If you don't have access to the equipment to do this, it will probably be simpler and cheaper to buy a small section of annealed bar stock from one of the online suppliers.

Patrick

I was happier when I thought that the Pearlite phase change to Austenite acted as a kind of catalyst to the remaining free ferrite in hypo-eutectoid steel.


I was told that that was not correct - but I cannot find anything that tells me what is happening.


Ignorance was bliss!!

Pretty tough question. I guess it comes down to the electronic structure of the iron-carbon system, but I guess we don't want to go to that level of detail.

One reason for that could be that the temperature at which pure ferrite changes to austenite is higher than that of iron-carbon alloy. The closer to the pure ferrite your system is (i.e. low C concentration) the more there will be ferrite in the system and thus the transition point to pure austenite phase will occur at higher temperatures than in the case of systems with higher C concentration.


I accept this. This describes the phase diagram with %C along the bottom. But why does AC3 slope, why is it not a constant temperature as the pearlite? Something must be happening to the free ferrite to change its phase change temperature.


Pearlite will change directly to austenite only at eutectoid composition (0.76 wt% C). At lower C concentrations pearlite will first change to ferrite+austenite phase before going completely to austenite phase. This ferrite+austenite phase lies between A1 and A3 lines.