guillotine ideas

[Dasher]

Hi all, hoping for some advice/ feedback. I'm in the process of making a hardy guillotine and have come across a couple of issues that more knowedgeable people might help with, my original intent was to make it to suit tooling made from old spring leaf, but the steel is an odd size, ie 80 mm wide and 14.5 mm thick, or most likely  17/ 32", which means when I run out of spring leaf, any new tooling will involve making blanks to fit, and generally discouraging making a quick die for a job, 2 questions come from that, 1 , is harder steel necessary for general  guillotine tasks? Especially if the actual tool face is an add on of higher grade particularly for cutting type tools. And 2, is it just simpler to make the guides suitable for readily available stock, and, if need be add a hard face at the working edge? I hope my intent is clear in the questions, and appreciate any advice, thx.

 

[pnut]

I would try to make the dies out of easily accessible stock size. It will make it harder in the future if you have to have an odd size of stock to make more tooling. Glad to see you're thinking ahead. 

Pnut (Mike)

[Dasher]

yep, thanks pnut, I'm sort of looking at it like what point is an aid, if you have to work more to make the aid?

 

[Glenn]

If you are going to use many different styles of dies, and continue to add to the list, than a standard size stock is recommended. You can find it on the street corner if you need more.  Whatever size die you choose, cut extras while you are set up and cutting. It saves time when you need one later.

What type metal are you going to be working in the guillotine? Are you going to work it hot or cold?  Then choose the metal for the dies that correspond to that usage.  

[Frosty]

If you're using scrounged stock look for leaf spring off UTEs, the stuff is everywhere so you can sort the same width and thickness. If you use Bimetal blades you can hack or band saw pieces easily. I just angle the vise on my cut off band saw for blanks it makes grinding finished guillotine dies much easier. I used 60* for the butcher dies, I use sharp butchers for cut offs and rounded the edges for isolating material.

The angle cut does half the work to make fuller dies. 

ONE 60* cut makes top and bottom die! However my top and bottom dies are different lengths, I'm not going out and measuring so for the purpose of discussion say my bottom die is 1.5" and the top die is 2.5" I cut at 60* x 2.5" on each end of the stock. I'd already cut a long piece of decent 5/16" x 2" leaf spring in half so I had 4 ends, making 4 60* to die blanks. THEN I reset the saw vise to 90* and cut both ends to 1.5" for 4 bottom die blanks.

Make sense? 

I made a number of 90* blanks for wide radius fullers and a couple flats. A flat bottom die under various shaped top dies has it's uses.

This strategy for cutting dies works just fine with a simple bolt together angle iron guillotine and hack saw. Though you don't keep switching ends with a hack saw. Yes?

Frosty The Lucky.

[Dasher]

Thanks guys, I'm thinking that at this stage , my tooling can be mostly mild steel, with harder dies as needed, as I have no bandsaw, or cold saw, most of my cutting is done , by either friction saw, which works pretty hard on thicker and harder stock, grinder, or gas, which, to me at least suggests I keep the tooling down around 12mm thick, my friction cut off saw handles that easy enough, but it doesn't like the 25mm dozer cutting edge I have. I'll re think it and see what I come up with

 

[ThomasPowers]

I would find a common size leaf spring and design for that. I generally like normalized dies of leaf spring for most tooling.

And for cutting:  Try to find someone like a blacksmith who has a forge and can cut the stock with a hot cut and then hot rasp it smooth.

[Dasher]

I'm not sure if you are taking the Mickey out of me with that last line or not Thomas, but as I'm new to this I'm not quite set up for that at this stage, even the guillotine, when done, will only be used for practise at this stage as I learn new methods of shaping steel.

 

[ThomasPowers]

Hot cutting was one of the first things I learned as I needed to make pieces I could easily work with from whatever sized stuff I scrounged. Helps a lot if you have someone who can hold the piece as you control the hot cut and hammer. I still often work in a shop with no electricity and so "keep the old ways alive".    If you are set up to hammer on hot steel you pretty much are set up to hot cut.

[Dasher]

Yes, got that, but almost always working solo, the main reason for the guillotine really, just trying to free 1 hand as much as I can, my left hand has a bit of nerve damage from an old work accident, and a lack of attention, or concentration can mean hot stuff falling to the floor or worse.

[pnut]

Have you ever seen a motorcycle chain holdfast?  One of those and a chisel profiled for hot cutting and your in business. You did mention nerve damage so this is assuming you can hold a chisel. 

Pnut (Mike)

I cut smallish stock on the unprofiled 90 degree flange on my RR track anvil.

 

[Dasher]

the damage is relatively minor, just if I try to hold anything for long periods, and my concentration fades, my grip can weaken, not normally much of an issue, if I'm carrying something fragile, I just adjust my angle of lift to support it more, hot stuff, with the added cantilever of tongs can be a small problem though, if something is heavier, I have an old , large pair of vice grips that Noah used building the ark, they are near bullet proof and just shrug off punishment, they save me having to grip as well as lift. The nasty 1st set of tongs I made are not super ergonomic, which I will rectify in coming days

[pnut]

A chain hold fast is anchored on one side of the anvil you put your work on the anvil face put the chain over it and keep tension on the loose end of the chain with your foot freeing up your tong hand to hold the chisel.

Pnut (Mike)

[Dasher]

That sounds pretty simple, thanks pnut.

 

[Glenn]

Make a S hook to fit into a link of the chain and into a hole on a foot plate. Leave the end of the foot plate a couple if inches in the air. The harder you step on the foot plate, the tighter the chain holds the work.  

[pnut]

That's a good idea Glenn, I don't know why that never occurred to me. Ring on the end of the chain or just stepping on the end of it is what I thought. I like the pedal type tensioner.

Pnut (Mike)

[Dasher]

good advice, thanks guys, I've been overthinking the guillotine, trying to re invent the wheel, I'm going for simple and easy now, dies will be a bit clunky, but I've got a fair bit of 50x 25mm bar, I'm going with that, should be simple to jig guides for it.

[pnut]

Simple is best. I've only been at this about five months and everything I've tried that has been simple has worked great. Everything complicated.....not so much.

Oh that hold fast doesn't need to be motorcycle chain any appropriate sized chain will work, motorcycle chain just lays flat.

Pnut (Mike)

Good luck and have fun.

[rockstar.esq]

Dasher,

One thing that doesn't get mentioned much is that the mass of your top die has a dramatic effect on how much work you can get done.  Large top dies have a lot of inertia holding them in place, so they require a lot of energy to get moving.  That means that you get less work done with every hammer blow.  In the design phase, it's super easy to talk yourself into thinking that versatility is a higher priority than efficiency. It naturally follows that bigger dies are "better". 

I built a guillotine tool a few years ago, and I can tell you that I'm planning to make a swingarm fuller because fullering dies in the guillotine tool waste too much of my effort.  Working alone, it's pretty awesome for refining precise work like tenons, but it's exhausting for any sort of heavy forging.  

[Dasher]

Thanks Rockstar, I had read that before somewhere, and it was 1 of the reasons I wanted to keep it smaller, like all of us, I'm trying to work with what I have on hand, and unlikely to be needed for any projects, to keep the top die weight down I'm going to reduce the vertical opening to just enough to remove the bottom dies without much drama, it should still give me near a 40 plus mm opening, and I see no need for any larger stock in my near future, but, who knows

[Sooty]

I haven’t got a guillotine but have just made my first spring swage (for making grapes) and wondered why a spring loaded guillotine hasn’t been produced so that it is open while putting stock in?

[ThomasPowers]

They have; but are not popular due to issues with switching out dies a lot.

I made a swing arm fuller that uses a spring:

You can set it open by tapping the left end or by lifting the right end and it will stay that way allowing you to set the workpiece and then whomp it!  Been using it for a couple of decades now, I've replaced the top bar several times and the bolt a lot more, (students, even mechanical engineering students don't seem to grasp that you hit the top bar right where it contacts the workpiece!)  The spring is a die spring that Ptree was selling at Q-S one year.

Funny thing; I made it without any welding using a scrap piece I found---the upright with the cross bar already welded on. I was just going to discard it when suddenly I saw the tool it could be with some grinding. The swinging bar is automotive coil spring, normalized.  It gets a lot of use in my shop!

[Irondragon Forge ClayWorks]

Maybe because you would have to overcome the spring with every hammer blow, a lot of wasted energy there (just a thought).

[rockstar.esq]

Sooty,

I think Irondragon is right.  My suspicion is that most folks make a guillotine are only thinking of how awesome it would be to strike a hammer blow with higher precision.  They don't realize how much of their hammer swinging effort gets wasted overcoming the drag and inertia of their guillotine tool until they use it for the first time.  After that, they probably don't want to add any more drag to the system.

There's an episode of the woodwrights shop with Roy Underhill where he visits with the Colonial Williamsburg blacksmith.  I noticed that the smith was using this stubbly little cold chisel to cut plate iron.  At the time, I put that down to thriftiness.  Now, I realize that the stubby length reduced mass which means every blow cuts just a little deeper.  It also keeps the point of impact closer to the anvil height which means the smith is getting a more natural swing with his hammer.  If that wasn't enough, the stubby chisel also allowed him to hold the plate and the chisel against the anvil face with one hand.