Scary monster

[PS_Bond]

Well, here it is so far...

1 gas forge of sorts. 3/4" sidearm burner, running between 0.35 and 2 bar. 2" Kaowool-like stuff lining it, soaked with ceramic hardener. Just fired it for the first time - a short run to set up the hardener. I'm not certain whether it will hit welding temperatures as it is yet (Mick! Help!), but it gets pretty hot judging by the colour of the scrap rod I heated up. The outside is probably running at 50C or so.

I've yet to add a floor in - probably using castable refractory; additionally, I'd like to coat the inside with ITC-100 or something similar but I haven't found any yet...

(image removed to save space)

[Mick Maxen]

Looks interesting Peter, if you can get steel to a yellow colour then you will be able to weld damascus using high carbon steel as one of the steel types in the mix, its the carbon content that dictates the welding temp. The gas forge I use welds carbon damascus no problem but struggles to reach a high enough temp to weld mild steel together, but will weld mild steel to high carbon steel no problem. What you must have is a reducing atmosphere in the forge, all this means is more gas than oxygen, if you have flames that come out of the door of the forge this shows more gas than air in the forge, which is what you want. If you can't get enough heat inside fill the opening up till you have something like a 4" square hole and mess about with the gas pressure. Alot of forges run on a very low pressure whereas mine runs best at about 50 psi. Peter, are you a member of BABA and if so are you going to the do at the weekend in Leatherhead, ticket only I'm afraid.
Mick.

[PS_Bond]

"Interesting", Mick? I know that curse of old... :D

I tried burning some mild in it, but I think the cavity is possibly too large for that - hence my interest in ITC100 & putting a sacrificial floor in. The flame *looked* neutral - and there wasn't much scale on the piece I was trying to burn (which is something Richard was criticising about gas forges) - if I ran up the pressure, there was easily 1' of flame front & back with minimal choke. My other regulator will run up to 4 bar, but I don't think I could get near the stock with the tongs I have at that pressure...

As for BABA - since I'm still a neophyte, I'd consider myself a fraud joining as yet.

[Mick Maxen]

Peter, a foot of flame out each end is over doing it a bit, try sealing one end up and reduce the size of the hole at the front so there is enough room to get your bar of steel in with ease and mess about with gas pressure and the choke, sounds like it has good potential though. As I have mentioned before somewhere on this forum the forge I use is a Swan Porta Forge originally designed for farriers, the inside is about 9" square and only 3-4" high. The only modification I have done from the original is to put a small door in the back for forging long rods and depending what I'm forging I use blocks of ceramic fibre board to make the front opening smaller, most times the front opening on the forge is about 3" square.
Mick.

[MushiSushi]

Have you put a Thermometer to that thing and how hot does it get when both ends are sealed up? .. I take it the air inlet is through that iron 'T' ...... have you got a blower on that? or is it just sucking in naturally? ... if so I was wondering if sealing both ends up will cause back pressure and stop it from sucking air?? :dunno: :togo:

[PS_Bond]

The only thermocouple I have to hand is encased in PTFE, so not really ideal for those temps. I'll bimble off to RS at some point in the future & pick up a suitable one.

Yes, the burner is a venturi design - so I'm a bit cautious about restricting the outlets too much. Having said that, there are a few designs (including Ron Reil's freon forge & the Blacksmith's Journal) that appear to drastically restrict the outlet. I'm not entirely sure, but it looks from the pictures as if the Swans are venturi-type burners too.

The forge now has a floor - I've used some of that mouldable firebrick from Purimachos. Much stiffer consistency than I had expected, so I had to be a bit careful not to damage the fibre (which turns out to be Kaowool after all).

I'll hopefully fire that tonight, and put some refractory in to close down the aperture. I think it was close to welding temps for high carbon, but I was trying to make a sparkler out of mild.

[MushiSushi]

what size propane tank are you using?

[PS_Bond]

Only a small one at the moment - 13kg.
Conveniently it is what the patio heater runs on, so if I decide it is chilling too fast, no great loss.

[PS_Bond]

Right. The beasty now has a floor and front and back walls, with about 2" square aperture each. I had to remove the choke tube, because I didn't feel it was burning quite as well as I wanted.

I ran it up to dry it - that's all, honest.

I now have a piece of welded cable.

OK, so it isn't perfect, there are inclusions and I've only got good welds for about 2" of its length (I've ground about halfway through so far to check the welds) - BUT. A burner built from scratch, a forge likewise, cable I spent blooming HOURS stripping down & rebuilding - and it works.

I think I deserve the beer now beside me :D

[MushiSushi]

Congratulations Peter!!!!

[PS_Bond]

An update on the scary monster...

I now have the zircon paint (finally!!!) and a couple of coats have been slathered onto the kaowool to a) give it some flux resistance and b) hopefully reflect more of the heat. Of course, once the paint had dried, I couldn't resist running it up for a quick go, and straightened out about 2m of garage door spring, using about 6" of it to make a steel (as in flint and ...). Works pretty well.

Put in a good thick floor of castable refractory last night; that will also get a coat of zircon, then I'll fit the front & back boards (ceramic board). Belt & braces on flux protection, and restricts the size of the cavity. I'll possibly put in a sheet stainless floor too, not decided yet.

*Then* I can get some flaming (no pun intended) practice in!

[MushiSushi]

I'll possibly put in a sheet stainless floor too, not decided yet.

316L is supposedly the most corrosion resistant

you ARE goping to start making some sharp pointy things soon aren't you?;)

[PS_Bond]

Well, I probably need to build some more tools first... :D

So many tangents, so little time.

[MushiSushi]

So many tangents, so little time.
yeah :rolleyes: ditto :twak:

[shing]

Like your forge Peter, will you be using it to heat treat stainless?

[Kevin]

Well, I probably need to build some more tools first... :D

So many tangents, so little time.

For knife making, I can usualy get away with just one hammer, one pair of tongs,a stiff wire brush and a hot cutter in my hardie (not forgetting the anvil).......it doesnt require much more than the basics to get started.

A simple spring fuller is useful to set the shoulders, but not necessary.

:biggthump

Kevin.

[Colin KC]

Looking good Peter, we need some pics of it in action though:)

[PS_Bond]

For knife making, I can usualy get away with just one hammer, one pair of tongs,a stiff wire brush and a hot cutter in my hardie (not forgetting the anvil).......it doesnt require much more than the basics to get started.


Spoilsport. I'm up to about 5 hammers, 10 pairs of tongs (oh yes, need to work on some of them :D), 4 brushes, hot cutter per the photo... And so on. :biggthump



A simple spring fuller is useful to set the shoulders, but not necessary.


Aha! Now *there's* another tool I "need"!
I still haven't finished off the vacuum setup, either.

As for HT of stainless - nah, I'll probably build another setup for that. Now I have what seems like a lifetime supply of refractories, I can cobble a few different designs together.

Action photos? "Here's one of me hitting my hand with the hammer, here's one of me trying to pick up black-hot stock by hand, here's one of me with my arm stuffed into the slack tub, here's one of me with the Spanish Inquisition..."?

[ugug]

here's one of me with the Spanish Inquisition..."?

no one expected that .. the forge is looking good.. :biggthump

[shing]

What did you use to make the kaowool hard? I've got a couple of ammo tins and making a gas kiln like the one of Mike Lamprey's and what to keep the kaowool under control.

[PS_Bond]

A combination of soaking it with Kaowool hardener (Tai Goo swears by porcelain slip, BTW) and a subsequent coating of zircon paint. Still not mechanically impervious, but a bit tougher than it would otherwise be.

[shing]

Thanks Peter

[PS_Bond]

Wow. This thing is now much more efficient. The combo of new floor, zircon paint and kaowool board front & back means I'm running as low as it can, and it is still blooming hot (orange to orange-yellow on O1). I'll see what pressure I need for welding temps as soon as I buy some more gas...

The zircon paint is not very mechanically strong, it would seem, so I'll have to put that stainless floor in.

Very surprised by the lack of scale (as opposed to coal or charcoal) - so at least it is rich to neutral.

[ugug]

Peter

can you give us an idea of how long from cold to non mag temps and what sort of pressure.. and given my industrial use of vinegar i am interested in how little scale .quick brush up ok to get rid of it?

cheers

ugug

[PS_Bond]

Depends on the stock size...

For the O1, I think I probably left it in for at least 5 mins from cold to bring an 8" long 1" section up to orange.

For the garage door spring, it took maybe a minute to heat (been making steels).

[MushiSushi]

OK gonna jump on this old one ..... peter what zircon paint did you use? did you try and get some ITC 100? From what I can tell, it seems to be some kind of ceramic glaze so any ceramic glaze should work ... i'm considering ordering a small amount of white glossy earthenware glaze that fires at 1300 and trying that ... less than £4 for half a kilo of powder from potclays ltd.

[PS_Bond]

The eponymous "zircon paint"... David Morgan put me onto a Northern Ireland bunch who stock ITC100, but I never got around to getting any as I found the paint worked quite well. Purimachos sell the paint as a flux-resistant coating, but it also boosts the temperature in the forge. ITC100 is also a zircon-based coating; Tai Goo uses porcelain slip to harden ceramic fibre (but it won't reflect as much).

[MushiSushi]

yeah he mentioned them to me too ....... bloody expensive !! :yikes: £40 a pint plus postage which is why i was thinking of a glaze, as that's basically what ITC100 seems to be ....... I've found a high tin content glaze which I think might be more reflective.

ordered some borax from potclays too .. not that i will be getting around to it anytime soon but thought I might put it on the order ..... might be purer as it's for pottery

[PS_Bond]

£40/pint??!! :yikes: Check http://www.anvilfire.com - they sell it at about $30 per pint, but I'm not sure what they charge for international shipping.

The paint is a bit thicker than the glazes I've played with in the past - think non-drip gloss viscosity (oh, OK, after you've squidged it a bit). I'd be interested in the results on the tin stuff - I'm not sure (off the top of my head) that tin compounds are as reflective, or as resistive to thos temperatures.

Looked at getting borax through Bath Pottery Supplies - borax frit isn't just borax... The stuff I've been getting from the Chinese grocers a) works well and b) works even better after dehydration - I'm definitely seeing an improvement in my welds with anhydrous.

[MushiSushi]

potclays do borax frit and plain borax ......... as for the tin glaze, it fires at 1290C so i'm guessing it will handle anything up to welding temps ..... once I get my digit out my thingamyjig .. I'll let you know how it goes

[MushiSushi]

ok potclays do 4 borax'ssss ... HT borax, soft borax, plain borax and borax frit

for plain borax go here http://www.potclays.co.uk/

and search for 3414