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Mikey98118

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  Rotary Tool Modification

  A regular rotary tool with small enough body diameter (ex. The Black and Decker three speed model) can be converted to be braced in an inline, rather than transverse position , similar to a miniature angle grinder, by making and mounting a small handle next to its spindle. Most rotary tools marketed today will work well for this. Only the old style rotary tools, which were designed to hang on a bracket, and power a flexible rotary accessory on its end, fail to work this way.

    All hand held rotary tools have a plastic threaded cap, which ensures that the two sides of its plastic body don’t come loose from each other (and to help mount a flexible rotary accessory on to its spindle). Most of these caps have metric threads. It is simple to match the threads from a bolt down at your hardware store with the plastic cap, and then buy a nut with the same thread.

    Run the nut onto your rotary tool, and ink mark the flat which ends up most closely facing the direction you want to weld or braze a 6” long flat bar onto. You now have a workable safety handle to use in controlling kickback, when using cutoff discs to do delicate cutting work.

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Good morning all. 

 

Mickey when it comes to kiln shelves I am wonder how flux resistant they can be, it sounds like you tend to use them alot. I can order these kiln shelves, this is the sds 

I know "good enough" isn't an appropriate question moreso my question is how long do you think 1/4"would last? I have the choice of 1/4" thick or 1/2", I like the idea of having a removable/replaceable floor but don't want to create more of a heat sync than necessary...... 

This company is in Canada "pottery supply house" 

Screenshot_20200301-102826_Drive.jpg

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I'm no chemist and haven't played with creating refractory coatings but I'm just curious if there's any way "calcined alumina" be beneficial in making a kiln wash/adding to a refractory product or would you just be running the same issues as the bentonite/veegum cracking up? 

I know this is sn old subject and admittedly I'm not up to date with the latest out comes. I just happened stumbled across this when searching for kiln shelves. 

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Regarding kiln shelves; high alumina kiln shelves are utterly resistant to flux. However, I always install my shelves in slots, which are notched into the forge sell, so that they can be easily removed, and reinstalled;or replaced. Why? because little is resistant to, and nothing utterly proof against the sticky mess that hot flux will make on any surface it touches. We can slow down the formation of flux on forge floors, but like weed control, we are never going to see perfect victory :P

Which brings us to the subject of kiln wash, cat litter, etc. Frosty, and the rest of the crew should jump right in here :D

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Thanks Mickey. I'm definitely thinking an easily replaceple floor would be ideal. I don't have slots built in this forge but swapping a 1/4" thick tile in and out would be fairly simple. 

I am not planning on welding big billets or anything crazy with this forge so I don't need a thick cast floor and soft bricks take a beating regardless of flux so I figure I'll try out your recommendation of the shelves. 

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30 minutes ago, Trevor84 said:

Thanks Mickey. I'm definitely thinking an easily replaceple floor would be ideal. I don't have slots built in this forge but swapping a 1/4" thick tile in and out would be fairly simple. 

Please let me know if you find 1/4" high alumina tile, in small amounts, on the market. So far I've only swung and missed :P

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I'm waiting to hear back from the company as this is the only sds I've found, I'm not sure if you can read it but it doesn't look very high in alumina. However they say they sell "high alumina" kiln shelves by the piece so I'll wait to hear back from them and let you know. 

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Okay, guess I'll jump in even though Mike's been handling things nicely. 

In it's most basic form a "kiln wash" is a final protective coating on the inside of a furnace to protect it from the environment in the chamber. Some kiln washes like ITC-100 are to prevent things from sticking to the kiln, the glaze on pottery firing to the furniture in the kiln so you can take pottery out. ITC makes a wide range of products to protect furnace interiors and hardware.

Unfortunately ITC-100 isn't the kind of final protective coating a propane forge really needs. It is better than nothing and is resistant to forge welding fluxes but it's not durable against mechanical erosion. It rubs off because it doesn't fire hard, it stays chalky. This is how it keeps things from sticking the zirconia in it isn't there as an IR re-radiator, it's there because if nearly inert so nothing can bond to it.

There are a number of kiln washes more suited to what we want: Plistex and Matrikote are the two that seem to be talked about most often on IFI. Neither contain zirconia but both fire hard and stay hard at high yellow temperatures. This is physical armor to make your forge more resistant to being worn away by cold steel rubbed and jammed in/on it. Both are also chemically resistant to high temperature caustics, borax base, forge welding fluxes. With me so far?

If you use Morgan Ceramics, K-26 IFBs fluxes don't have as much effect and they're reasonably tough. Still, they're soft fire brick so some physical armor is a good thing and increasing their resistance to flux is better. High alumina, Kiln shelf is very tough, it's designed to support weight bridged between pegs. Shelves, literally so it doesn't get near soft in our forges and isn't going to scrape up even if you're a ham handed clod about inserting and removing work in the forge. 

Kastolite 30 is resistant to fluxes though not as resistant as kiln shelf, the right kind of kiln shelf that is. I haven't noticed any erosion due to flux but I don't spend a lot of time using it so I'm not a good judge of how long it'll last without further protection.

Where things are getting interesting lately is with experimenting with zirconia. Besides being very chemically resistant to most everything, it conducts heat VERY slowly so it just sits there absorbing energy. Nothing can just absorb energy so it gets conducted or radiated away in 3D. The only available direction the IR can move easily is back into the forge chamber, at your work. It's painted on the forge's hard liner which can't absorb heat as easily as an open chamber so it doesn't go back well and beside it is more zirconium kiln wash and the energy can't go that way at all, energy is pushing back just as hard. Making sense? This is why some of us are experimenting with home brew high zirconia kiln washes and surprise of surprises Bentonite seems to be an excellent binder and fires hard at forge temps.

That thin layer of kiln wash, protects what's under it from heat, high temp chemistry and physical abuse. If you're at all confused by my ramblings you're probably a normal guy and should just buy a good kiln wash, Plistex or Katrikote though general consensus on IFI is leaning towards Plistex as the better of the two. 

Frosty The Lucky.

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After the following I have done here I actually do follow for the most part. Like I say I'm no chemist but I'm definitely getting the gyst of it, I've been reading through these threads for the last year or so trying to get a decent visual of everything. 

The floor in my forge is soft Ifb and got beat up pretty bad and then I leveled it out with high alumina mortar but low and behold...... mortar just won't stay solid at high temp when used this way ;) that's why I'm thinking of replacing my bricks with others I have already and then using a kiln shelf when I plan on welding. 

The main forge body (D forge) has a kast-o-lite lining but it would be nice to have a higher alumina wash on it or better yet the zirconia wash.

When I ordered some other stuff from the company I mentioned above I grabbed a bag of "Ultrox" (zircopax) and a bag of bentonite clay. I may just have to try out a thin wash, I already have the kast-o-lite shell so I just need a thin wash so I probably don't have to worry as much about it cracking up. I just happened to see that alumina being offered as a dry product from this site, they have a large selection of products available on small quantities. 

It's sounding like 3% bentonite 97% zircopax and mix to a latex paint consistency, dab it on and give it a long time to dry...... 

I would just order some plistex Burt everywhere I quote it it comes to almost $100 after shipping. I could get a half pint of ITC 100 for $50 but as you say and I've read is that it's designed to be able to flake off so a person can clean their kiln shelves easier when doing pottery. That's why I'm curious about the he brew since it's like $30 and it sounds like there are some decent benefits. 

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Your plan sounds good, either of them. Can't Glenn get you a small quantity of Plistex? Is shipping to Canada that expensive now? I wouldn't want a full load from a large distributor either, 5lbs. is more than enough. Heck if I had any I'd just mail some to you flat rate. Does flat rate work from the Us to Canada? 

My next kiln wash is going to be the above 3% bentonite - 97% zircopax (B&Z). I'll be playing with different moisture contents though as I'm going to do more than just wash the flame face. I'm thinking the floor of my next (I HOPE not crazy too large!!) forge would be a good test bed for using a thick B&Z paste maybe 1/4" thick as the direct flame face. 

Another thought I had for experimentation was mixing Plistex and zircopax but I'm skyballing that idea it'd take testing before I'd put it on a forge liner.

I think you have a good handle on the subject. 

Frosty The Lucky.

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Ya, no flat rate boxes here, some stores are able to ship at better rates than others but I think that's when they have larger contracts with curries or something.

I think the shipping was more than the actual product when I talked to Glen last I think.

I was going to just add the zircopax to my mortar but the supplier recommended I try the bentonite, it turns out he knew more about this stuff than I did. So between him and you guys I may have everything I need...... 

Being able to make ones own bricks would be a treat once you get the recipe down that is. If you can make strong re emmisive tiles instead of just strong would be a nice touch. 

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  • 5 weeks later...

Hello all, 

My name is Michael. This is my first post but I have gone through this thread and many otheres.  My son and I started forging last summer.  The forge we have we  bought off Etsy.  Its not the best and not very well insulated so I am building a new one.  I have read this thread along with many others and want to make sure I am on the right path.  My main question is about burner angle.  I get that you want the flame to hit something that can take the abuse and yet still circulate around the forge.  Below is what I have and what I plan to do.

Party Helium tank (approx 9.5 diameter and 12.75 long outside measurments)

 I purchased my forge supplies and burner from Larry Z. 

1@ Z burner 8# 1in Insulating blanket

Enough HarbisonWalker International INSWOOL to do two layers

Ins-tuff Ceramic-Fiber Rigidizer

Kast-0-lite 30

Plistix 900F

Here are a couple quick pics I drew up.  Not to scale, just eyeballing.  Do either of these burner angle look correct? I am planning on pouring a Kast-O-Lite floor and putting in fillets so there are no sharp edges on the floor.

angle-1.jpg.7161ca319d8e8267ae94cd83354255ee.jpg

angle-2.jpg.29a1e6b657db7bb0d00abde8aaedde62.jpg

 

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Welcome aboard Michael, glad to have you. Can't have too many Alaskans you know. Larry makes good burners and his kits make a good forge. I'm not a fan of the commercial rigidizers, I bought a can and it went bad after a while. It worked fine but it was pretty expensive for how much I used. I bought fumed silica at the Plastics place here in Wasilla, can't recall the name though. It mixes with clean water and you spray it on then cure it with a torch or the burner. 

The top burner alignment would work but I don't think I've seen it in action before.

The second drawing isn't a good alignment, it's directing the flame into a corner which will cause  turbulent atmosphere in the forge but the problem is back pressure which inhibits the burner's performance. 

A more common orientation would be to move burner 2 back so the flame is hitting the floor ahead of center this will cause a strong vortex for more even heat in the chamber. 

Another orientation that's been around for I don't know how long but works well is horizontal just below the top of the chamber. You don't see this orientation so much anymore but it works pretty well. Makes a strong vortex without being aimed right at the work which can cause a flame shadow for cooler spots. 

Next time you're down Wasilla way give me a shout in advance we'll get together and swap tall Talkeetna tales. Pandemic allowing of course.

Be safe be well,

Frosty The Lucky.

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Thanks Frosty,

We just moved from Palmer to Talkeetna about a year ago.  Both kids are graduated and we found a place we love.  After the nastiness with covid-19, I would love to swing by and chat.  Thanks for the info on burner placement.  So if I get you right it would look something like this.

 

angle-3.jpg

Just trying to do it right.  I have 100# propane bottle but with inefficient as the old forge was we burned through it pretty quick.  We made a ton of hooks, leaves and then I finally made my first tool.  A pair of tongs.  channel lock plyers just wasn't cutting it.

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None of those positions is optimal, since all of them will make the flame impinge on the wall at short distance. My favorite position has the the burner opening two inches away from top-dead-center, with the burner aimed to impinge on a high alumina kiln shelf, near to its nearest edge. Others prefer to aim the burner diagonally downward toward the far edge of the kiln shelf, or toward a high alumina cast refractory floor's far edge. There are other good positions possible, with other forge shapes, and refractory interiors. But this is the short answer.

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Not that close to the top Michael but that's the basic idea. It's old school but it works. 

Mikey has spent a lot of time doing more specific studies of this stuff than I and if you have to choose, choose his opinion over mine. 

Propane flame is very chemically active at forge temperature and tends to cause chemical erosion to many refractories. KOL and Plistex 900 are both pretty resistant to propane flame and flux erosion making a kiln shelf an extra cherry on the sunday. 

When we get to specifics about your plans we can discuss various ratios, I'm taking your drawings as concept sketches. If they're actually scale drawings then you're going to want a number of small diameter burners if you want even heat. 

Your graphic make it look like a really skinny chamber which changes things.

Frosty The Lucky.

 

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3 hours ago, Another FrankenBurner said:

I believe he is meaning something like this.  This prevents the back pressure Frosty was talking about while also not impinging directly on the wall.  

forge.png.4fa9ec4af6f2460ac8647fdc5230a284.png

Thanks Frankenburner

1 hour ago, Frosty said:

Not that close to the top Michael but that's the basic idea. It's old school but it works. 

Mikey has spent a lot of time doing more specific studies of this stuff than I and if you have to choose, choose his opinion over mine. 

Propane flame is very chemically active at forge temperature and tends to cause chemical erosion to many refractories. KOL and Plistex 900 are both pretty resistant to propane flame and flux erosion making a kiln shelf an extra cherry on the sunday. 

When we get to specifics about your plans we can discuss various ratios, I'm taking your drawings as concept sketches. If they're actually scale drawings then you're going to want a number of small diameter burners if you want even heat. 

Your graphic make it look like a really skinny chamber which changes things.

Frosty The Lucky.

 

Frosty,

I kind of mispoke.  I have everything in my list.  I dont mind building some a pair of smaller burners even though I have an new Z burner.  I would like it to do it right the first time.  

Would it be better to switch to a propane tank with 2 burners?  I have experience flushing and cutting cylinders.  A couple years back I taught myself to weld so I could build a Reverse flow smoker.  I used an old propane tank with that.

Michael

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I saw the list you posted but I had to stop figuring out the volume of people's forges for them some time ago, folks would get angry if I didn't so I had to stop all together.  Telling me the size of the shell doesn't tell me what the finished volume or shape will be. However, If Larry said  that burner is good then it is, he knows what he's doing. I won't second guess him.

It'll be a fine forge especially to start with, everybody who's done this a while has a couple forges collecting dust. As your skills grow your interests will grow or change and you'll have a better idea of what you want or need in a forge and your next one will be a better fit.

Frosty The Lucky.

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I get where you are coming from Frosty.  My guess is that after everything is said and done the interior of the forge will be 5x8.  After saying it it sounds a bit small.  Im planning on concentrating on on tool making this year.  With the biggest thing is trying to make my own rounding hammer. Starting to wonder if I should switch to a propane cylinder.  I have been having a hard time finding something for a shell.

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