What did you do today in pyro?

[lloyd]

Mikee, is there anything wrong with starting BIG, but putting a 'louver shutter' over the holes, so it can be adjusted?

 

I've found that different 'cuts' of wood cook differently, and need different air. Fixed holes prevent one from adjusting the airflow.

 

Lloyd

[chuckufarley]

I agree Lloyd. After getting mine pretty dialed in for ERC chips, I tried cooking up some pine chips I had. Cooked way too hot, and left patches of unburned shavings in the bucket. Im planning on making one like you've described soon. 55 gallon barrel, or water pressure tank, with a false bottom and adjustable air intake valve. I think the air adjustability is key unless your only cooking one type, and style of wood, then it might not be so important.

[mikeee]

Using an adjustable shutter would be the best solution, but most people starting

down the path of TLUD usually punch holes on the first couple of cookers they make. (paint cans & 5-gallon buckets)

Once they understand the process they usually build the "keeper" cooker of the size and quality for the long haul.

[chuckufarley]

Yes Mikeee I agree that starting out a paint can or five gallon bucket is the easiest, and probably best beginning, option. I think that they can work very well, and are cheap and fairly easy to make. My previous comment was just what I wanted to achieve in the next step of my TLUD progression.

[OldMarine]

Lit off a dozen rockets last night without incident then set the field on fire with a catalytic converter! Burned half an acre of Broom Sage before the FD came to the rescue.

[mikeee]

Finished a 2nd set of Teak wood insert formers 1-1/8" thru 2".

 

[Boophoenix]

Roger, I hope to work on just that task before to long I've been slowly getting a design started to try to give a hard number to some of the options. I've got a few more items to get ironed out and maybe I can get up and rolling. The testing is for charcoal,in general, but cooking methods will be a part of it along with temps. The hope is to do a laundry list of tests to justify the results.

 

It was nice to see some agreeable opinions or facts as to what I suspect I'm gonna find when I get rolling.

[mikeee]

One other change you can make on a TLUD is the height of the flue stack and the number of holes

around the collar where the flue stack connects to the TLUD chamber.

With the correct amount of holes in the collar you add enough combustion air to burn the flue gases.

The hot flue gases increase the amount of draft on the TLUD combustion chamber keeping a steady burn.

If the flue is too short or not enough air vents (holes) in the collar you will have a weak draft on your TLUD

chamber, this can lead to your charcoal going out from lack of combustion air being drawn in from the bottom

TLUD chamber holes. If your TLUD cooker is burning too hot you can sometimes shorten the flue stack.

[lloyd]

Mikeee,

 

I've never found it necessary to alter either the stack height nor the stack's intake air vents. I built mine 'long enough' and with 'enough' vents to handle any draft situation.

 

With a proper diffuser in the bottom, I've found that the only thing I ever need to change is the intake vent at the bottom of the barrel. The rest seems to sort-of automatically 'take care of itself', so long as it's enough to handle the effluent gasses.

 

Lloyd

[mikeee]

Lloyd,

 

The taller the flue stack the longer the hot flue gases are in the stack which will increase the velocity

of the hot flue gases, increasing the draft on the TLUD cooker. This affect will increase a certain percentage

until you reach the length of flue stack that either begins to cool the gases or starts to restrict the air flow from

friction loss and pressure drops in the total height of the flue stack.

 

Having an adjustable shutter on the bottom of the cooker is one of the best solutions for controlling the cook rate.

Adding or subtracting 1 foot pieces of flue stack is another way of affecting the intensity of the cook.

Having a flue stack collar with larger, smaller, fewer holes can also affect the combustion of the hot flue gases.

If your TLUD cooker has a lot of smoke leaving the stack it means the flue gases are not burning and have cooled

down. Adding more air at the flue stack collar adds combustion air to the flue stack and increases the combustion

of the hot flue gases. These solutions will work for the 1-gallon paint can and 5-gallon bucket TLUD cookers.

[lloyd]

Mikee, I'm aware of all those relationships.

 

When my cooker is running with a 'low flow' load, I get flames in the stack, but not high enough to exit the top. When cooking at a high flow, CLEAN flames emit from the top of the stack, but not smoke (of course, smoke at the very beginning, but once the burn is established, none).

 

I have never adjusted or even felt the need to adjust the stack length or the bottom vents of the stack... only the shutter at the bottom of the tank.

 

I think part of the reason it works nicely, is that I have a very effective diffuser in the bottom of the tank, so the airflow over the entire area of the load is pretty uniform. I don't seem to get the "under-cooked middle" phenomenon.

 

When the stack wants to draw too much air, I just close the bottom inflow shutter a little. Just looking at it from an 'engineering' standpoint -- the stack CANNOT draw more air through the tank than what I allow to flow in the bottom. <shrug>

 

 

So far, it's worked fine with split splints, 1" twigs, and baled cedar chips. I don't think the stack or its intake vent needs any modifications.

 

LLoyd

[OldMarine]

Have you posted any pics of your TLUD Lloyd? I'm sure I could pick Brad's brain to get the gist of it but a picture is worth...

[lloyd]

Yep... published a couple on FW.com. It's a simple affair, made from a 40-gallon ('equivalent') 'tall boy' bladder tank. I think the gross capacity is about 33 gallons.... 16" dia. by 38" high internal.

 

Lloyd

Edited February 12, 2017 by lloyd

[OldMarine]

Yep... published a couple on FW.com. It's a simple affair, made from a 40-gallon ('equivalent') 'tall boy' bladder tank. I think the gross capacity is about 33 gallons.... 16" dia. by 38" high internal.

 

Lloyd

Excellent! I'll have to hunt them down. Thanks.

[lloyd]

What I did in pyro today was finish the new prototype for a 60mm aerial shell "launch assembly" component. It's designed to be made by injection-molding, and considered a disposable component.

 

'Had to do quite a bit of research on the strength, elasticity, and molding shrinkage of polystyrene/polybutadiene 'impact grade' molding resins!

 

Lloyd

[otto]

I went to the auction site and retrieved my bounty of silicon chips.

 

There is a pile..... Now to determine a processing procedure.

[lloyd]

As has been mentioned before, it's extremely brittle. Almost any medium in a ball mill would crush it to dust rather quickly.

 

Lloyd

[otto]

Thanks Lloyd.

 

I have a number of media and jar options available.

 

Media: 3/4 - 1" ceramic, 1/2" Zirc-M cylpebs, 1/2" foundry type lead (its really hard for lead), and (not quite enough) 1/2 SS bolts w/nuts.

 

Jars: rubber lined hex and "sort of" lined hex (by that it's steel jars with worn rubber lining) or I have the material to build a 10" PVC jar with or with out lift bars (optimum RPM shouldn't need 'em).

 

I'm sure that steel jars with worn lining and the SS nuts/bolts would be fastest.

 

I just took a look at what polycrystalline Si was actually selling for on eBay (200g for $12 free ship from China) and was astounded (considering what I have invested). I need to assess exactly what I've got before I do much more.

 

This stuff came from a business that manufactured parts for satellites (I was told) so should be very high purity.

 

I will certainly offer some "process your own" but I'd like to be able to do the ready to use as well. I'm not looking for a windfall either. Maybe just get a couple of tooling sets from Caleb.

 

Stay tuned. Or PM me for a deal...

[OldMarine]

Since it's pouring rain I had to get my HF workbench put together and moved inside ASAP tonight. The bottom shelf holds all but 1 of my screens so I'm good with it (I can retire one of the intermediate ones to a drying screen) and am darned happy to open some shelf space for my "batch sized" chem containers.

[NeighborJ]

Looks good Pat. My 15yo son has been eyeing up that same workbench as a munitions reloading bench, it seems sturdy.

[OldMarine]

The bench is very sturdy although it had some pressed board parts. I really like the vise on the side.

[lloyd]

When those first came out, they had a 'super deal' on them. I got three at $99 each, in order to make an approximately-square large layout table.

 

I left out the glue fastening the legs to the tops, so I may disassemble and store individual ones on the wall, when I don't need the whole work area.

 

They are not as "strong as they look", because the edges are MUCH thicker than the top-deck, but they are plenty strong-enough for any kind of layout or pasting work... just not for 'pounding' work.

 

Lloyd

[OldMarine]

Cutting/pasting paper and shell assembly is all I plan on using it for but I'm sure it'll be used for other stuff just like all my other stuff!

[Sulphurstan]

Made a burn test of my first willow charcoal BP, and yes! The difference with pine charcoal is remarquable. I wouldnt believe it much until making it by myself! It is worth the work of making the charcoal myself, ballmilling it with the sulfur, mixing it with kno3, precipitating with cia method, drying, granulating....

[Ubehage]

Made a burn test of my first willow charcoal BP, and yes! The difference with pine charcoal is remarquable. I wouldnt believe it much until making it by myself! It is worth the work of making the charcoal myself, ballmilling it with the sulfur, mixing it with kno3, precipitating with cia method, drying, granulating....

Nice to know about the willow charcoal. I might try it some day

 

On another note, you will also get better BP if you mill the KNO3 with the other ingredients.

If you worry about the hazard of having a drum full of explosives, you can also mill the KNO3 seperately before mixing as usual.

 

The CIA-method is said to lower the overall quality of BP, due to some KNO3 being "lost" in the water. As someone who started with the CIA-method myself, I confirm that.

It's better to use less water and a little more work. I use 20% water with 10% dextrin. That equals to 2% dextrin in the final composition.

Here's a helpful example of how to wet BP with less water, by Bangkok Pyro:

https://www.youtube.com/watch?v=q6gE8wkTPdE