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blikseme300
04-03-2013, 03:52 PM
Some time ago I built 2 larger electric melting pots and I documented one of these here: http://bliksemseplek.com/boolits.html

I recently acquired 4 x 1600W 240V 6"idx4"h heater bands and am looking for somebody to share in the spoils/effort. The deal I am interested in is for somebody to supply the 4 black steel tubes needed and I will supply a complete unit made up and ready to connect to your power source. The capacity of the pot is about 45lbs so get ready for some serious casting with one of these. I will document the project progress here to encourage others that are contemplating doing this kind of project themselves.

Bliksem

VHoward
04-03-2013, 07:22 PM
I wish I had some pipe to send you. How much would a pot such as this cost?

itry
04-03-2013, 08:30 PM
Got some specks on the pipe you need? A guy could always poke around behind the barn and see what he trips on.
itry

blikseme300
04-03-2013, 09:10 PM
I wish I had some pipe to send you. How much would a pot such as this cost?

Other than my time the previous units cost less than $50 to build. The 4 heater bands I just got cost me about $10 each so the cost should be about the same. I don't buy at retail but scour the surplus sales on evilbay and Craigslist for bands. The component that adds the most value to the smelter setup is a PID controller. These I don't scrimp on and I like to support Auber Instruments. So for about $200 I have a setup that makes casting a pleasure.

blikseme300
04-03-2013, 09:17 PM
Got some specks on the pipe you need? A guy could always poke around behind the barn and see what he trips on.
itry

The pipe needs to be a true 6" OD but can be thin wall black steel. I'm not familiar with the schedule gauges but 1/8" thick walls are ok. The pipe I used for my previous units were scraps from the fire control sprinkler system fitted at one of our packing facilities. Not heavy gauge and not rust proof but was easy to work with.

The plan is to make one for myself, one for a newbie I got hooked to casting, one for the pipe donor and the fourth will be donated to be auctioned here to help Ken.

Each pot will need a 5-6" long section and all the other materials and fabrication I will supply.

blikseme300
04-03-2013, 09:18 PM
This is what the heater looks like.
66336

blikseme300
04-03-2013, 09:49 PM
I had a PM question and I need to clarify my offer/request. You supply me tubes for the 4 smelting pots and you will receive one unit ready to use in return for supplying the tubes.

Alan in Vermont
04-03-2013, 10:55 PM
FYI, 6" steel PIPE is going to be 6.625" OD, regardless of the Schedule, the ID varies, getting smaller as the Schedule # goes up. I think to get a true 6" OD you would have to go to tubing material which is spec'd by OD and wall thickness.

Pipe will be a bunch cheaper than tubing but if it won't fit iside the heater band that is a moot point.

JIMinPHX
04-03-2013, 10:55 PM
When you say 6" diameter, is that 6.00" or do you have a fairly loose range to work with that is around 6", for instance 5.75"-6.25" or 5.5"-6.5".

You can get pretty much just want you want, if you are willing to pay tubing prices.

http://www.arcelormittal.com/tubular/images/ArcelorMittal_DOMSpecs.pdf

If you can use a standard pipe size, then things get a whole lot less expensive.

http://www.maselmon.com/Content.aspx?ContentID=24

blikseme300
04-03-2013, 11:01 PM
FYI, 6" steel PIPE is going to be 6.625" OD, regardless of the Schedule, the ID varies, getting smaller as the Schedule # goes up. I think to get a true 6" OD you would have to go to tubing material which is spec'd by OD and wall thickness.

Pipe will be a bunch cheaper than tubing but if it won't fit iside the heater band that is a moot point.

Alan,

The diameter needed is 6.0". Thanks for sharing how the schedule works as I was not aware what the relationships between sizes and schedule are. Hopefully somebody here has access to what is needed or I will just have more bits to add to my bone yard.

country gent
04-03-2013, 11:32 PM
Mechanical tubing isnt a "schedule" plumbing pipe its is made to a specific Id od and wall thickness. It is more expensive than standard black iron pipe. but has a better finish and normally is a stronger alloy.

Spawn-Inc
04-04-2013, 06:29 PM
based on the crimp in the pipe of your first pot, if you want the same thing, you need to be looking for sprinkler piping. so call around to various sprinkler system installers.

dragonrider
04-04-2013, 07:51 PM
From Speedy Metals 6" tube with .250" wall thickness is $6.31 per inch. $25.24 for a 4 inch piece, or $100.96 for 4 pieces plus shipping, which in my case would be $22.84. Not a bad price, of course free would be better.
http://www.speedymetals.com/pc-3610-8242-6-od-x-250-wall-dom-steel-tube.aspx

A single 18" piece would be $95.87 and a couple of dollars less shipping.

itry
04-04-2013, 09:13 PM
Thanks for the details. I will see what I can come up with. itry

dbosman
04-04-2013, 09:37 PM
I wish I had $124 to spare.

USMC87
04-04-2013, 09:49 PM
I can get the pipe very easy, My friend owns a shop here and I CAN get about anything you need.

blikseme300
04-05-2013, 06:37 AM
From Speedy Metals 6" tube with .250" wall thickness is $6.31 per inch. $25.24 for a 4 inch piece, or $100.96 for 4 pieces plus shipping, which in my case would be $22.84. Not a bad price, of course free would be better.
http://www.speedymetals.com/pc-3610-8242-6-od-x-250-wall-dom-steel-tube.aspx

A single 18" piece would be $95.87 and a couple of dollars less shipping.

Thank you for this source. It might be an option and I will think about it once this crazy week is done.,work sure interferes with casting boolits and shooting.

blikseme300
04-05-2013, 06:43 AM
based on the crimp in the pipe of your first pot, if you want the same thing, you need to be looking for sprinkler piping. so call around to various sprinkler system installers.

I don't need the crimp but the off-cuts I were given were from the ends of prefabricated pipes and they came with the gift. I did call the installer but they had no 6" pipe.

McMaster sells vacuum vessel material which is true 6"OD with 2mm wall thickness at not too high a price. I am just having to wait until this weekend to have time to decide how to proceed.

Liberty'sSon
04-05-2013, 07:58 AM
I will be getting bids from two fabricators on another project I am doing this Monday. I will check and see if they have anything and send a pm.

Liberty'sSon
04-06-2013, 02:02 PM
Blikseme300, pm sent. Please respond with which OD you want and I can have the pipe cut on Monday.

jroc
04-07-2013, 02:10 PM
Blikseme300, this don't help you out none as far as finding what you need but I have a question. What is the difference in heater bands between a ceramic band and a mica band? Is one better than the other and if so why. I have looked at your other build and have been real interested in building one myself. Thanks for any info. Jim

blikseme300
04-07-2013, 06:03 PM
Blikseme300, this don't help you out none as far as finding what you need but I have a question. What is the difference in heater bands between a ceramic band and a mica band? Is one better than the other and if so why. I have looked at your other build and have been real interested in building one myself. Thanks for any info. Jim

Thee are pros and cons for both and the largest factor in choosing has been cost. Mica is rigid and will need an insulating jacket while ceramic is flexible and already insulated in the ceramic, to an extent. The biggest gotcha with mica is the availability of tubing or pipe to fit the band as I have just discovered.

A factor to consider is the Wattage of the smelter. The higher the Watt density the quicker the pot will return to the set temperature. In my experiments with previous pots I discovered that when you reach about 35 Watts per pound the recovery time when adding ingots is very short. The biggest advantage of a 50 to 70lb smelter is that you very rarely need to add ingots during a casting session. These smelters are controlled by a PID unit for repeatable results when casting so consistency is achieved during every casting session.