Induction forger


#21
  • Do not know where.
  • Our current lease ends August of 2019

Assuming a suitable place is located so we can move from current site, we’d rent the new facility one or two months in advance to have site build-out basically done, moving and installing equipment after that’s completed and new place being opened and functional in September.

There is always a possibility that if something were to come up in well before the lease here is up, we’d see if we could find a tenant that likes this space, sub-lease until our our lease expires.

We meet with our real estate on a regular basis who updates us on what’s available. We are starting to actively look for places now - 18 months out and not waiting until the end. We were caught short this last last, because we’d been approached about the possibility of renting the space next to us (near perfect solution) but that fell through when there corporate office changed their mind (what I was told) on moving and that left us with almost no time left.


#22

Just curios…has the landlord already indicated that he will not renew our lease, or is raising the cost to a point that doesn’t makes sense to stay? Or is a new building the plan regardless? Seems like it would be expensive to move vs resigning.

Like I said…just curios.


#23

We have right to renew and first option on space adjacent to us.


#24

I have 8 railroad spikes coming in.

If someone needs one, let me know. Like $2 each.


#25

I’ll take one Steve, drop it in my box, I’ll get you the cash thursday?


#26

The induction demo is amazing. As a EE I’ve got to know - what sort of AC signal is going through that short copper coil? (voltage, current, freq)


#27

I don’t know that anyone would know that without a lot of research in looking at the components. Documentation on anything technical is rather lacking on that device. It took us a good while to find out what the input current requirements were.


#28

Try building one to help you understand it.

This one looks pretty easy to make. I wonder if it will work very well at 13.8v since I have a 30A Astron power supply I can use with it.


#29

Do remember that the nameplate current on an astron is at a limited duty cycle, something like 50%.


#30

Yup!

It’s right about 20A for continuous duty.

I’m not sure where the heat issue lies more - with the transformer or the current pass transistors. If it’s the transformer, there’s not much you can do, but for the transistors it’s easy to add fans to the heatsinks. :slight_smile:


#31

Could I reasonably build an induction loop for guitar side bending? I am using steel straps on either side of the wood (to prevent cracking), which would induction heat. Many builders are using lightbulbs for heat. Or heating blankets, but they come in dimensions that are less than ideal for my build. I feel like an induction loop would be great because it also minimizes heat on the structure, which is mostly plywood, lined with AL foil. I would be lost as to good design, but it seems like it could work.


#32

I imagine that it would need to be of significantly lesser power, but to what extent I am not sure.


#33

The small induction furnace we have in Jewelry / Small Metals is only about 2KW.
The industrial induction furnaces used for jewelry production have a circuit which pulls a vacuum when the chamber is closed, then adapts the induction coil to the metal you are melting.
When a set temperature is reached, the metal port opens to let the metal flow into the investment in the flask underneath.
The constant-use production models are in the 35 to 40KW range and use three-phase power.
They start about 30kHz and then increase the frequency to somewhere about 120kHz.
You can measure the the copper coil in the Metal Shop unit and make a long, narrow (almost touching) U-shaped or dog-bone / taper coil to allow for long blade forging without having to change any capacitors, etc.
If you set a couple of long crucibles or a firebrick below the coil then you could just rest the blade close to the coil.
I have some investment for platinum casting that is not difficult to make into firebrick if you want to go that route.
Give me a shout and we can look at the specs on the induction unit in the Metal Shop together.


#34

Hey, old thread so I just want to be sure every one knows the induction forge is now training required. There is a lot of safety to keep in mind!

The one we have is a 25kw if I remember correctly, its the middle size for its kind of unit. The induction forge as it is works great for all kinds of forging including knives you just need to use the kiln in metal shop to normalize it before heat treating.

We do eventually want to make a flat coil and a crucible coil but we don’t really have the space yet.


#35

Excellent - - 25KW should be plenty - - let me know when you are ready for help with the crucible coil and I will set aside some time.
Jewelry has about half a dozen of the 3Kg taller graphite crucibles.
If budget is an issue, then I am willing to buy the coil material and make the holder if necessary.
There may be some porcelain sheaths that can hold the taller graphite crucibles for cheap on fleabay.
BTW, I just listed some Metal Shop classes to help drum up more interest…


#36

I seem to remember @Coul buying some crucibles for it.


#37

Awesome, it’ll be after the expansion tho.


#38

I spent like 3 days trying to figure out how to make a custom gas fired forge to do the exact same thing as this, for both edge tempering and beveling


#39

if you just need some 1/4 copper tubing, check with A/C companies. they throw away yards of scrap every week. You might need to clean it out, but most of them will probably let you take a single 6 ft piece if you ask nicely first


#40

They have made custom hoops. The flare end is metric, 10mm I think,