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scott curtis
08-22-2011, 05:06 PM
I found this mold in a box bought at an auction. it's a cadwelder m-108 #'s 6,14,&15. it's a clamshell design, hinge on 1 end hole on opposite. looking to date. Any and all help would be helpful.

Catshooter
08-22-2011, 07:10 PM
Google Cadweld or exothermic welding. Often using a graphite mould, it is a method of using a powdered mix of chemicals that once ignited burns hot enough to weld what you're trying to weld together, together. As an electrician we used it to weld copper cable to other cabling or to steel ground rods, rebar, things like that.

Hopes this helps.


Cat

slide
08-22-2011, 07:23 PM
Catshooter hit the nail on the head. We used them to weld copper wire to grounds rods in substations. You needed to wear cutting glasses or look away when you lit it. Very,Very bright!

MT Gianni
08-22-2011, 10:32 PM
We quit using it in the late 80's to attach copper tracer wire to steel gas line ahead of a plastic transition fitting. There was concerns about stressing the pipe by heating it unevenly. Use good eye protectios as wa said and we lit the top with a spark lighter.

Wayne Smith
08-23-2011, 08:02 AM
Pardon my ignorance, but something seems to be missing here. He's talking about a mold, you guys are talking about welding? You may know the connection, but I need things like this explained in small steps!!

mag44uk
08-23-2011, 10:37 AM
Pardon my ignorance, but something seems to be missing here. He's talking about a mold, you guys are talking about welding? You may know the connection, but I need things like this explained in small steps!!

I thought it was just me!
Tony :?

sleeper78
08-23-2011, 11:06 AM
I'm not sure of all of the uses of Cad welding, however, I'll tell you what I used it for. I used to build cell phone towers. On a cell site EVERYTHING needs to be grounded. We ran spools and spools of #2 copper solid wire around the site underground connecting everything to ground rods. To weld this wire to ground rods, chain link fence posts, other pieces of wire etc. you had to Cad weld.

To cad weld you take mold (just like a boolit casting mold) and place in on, over, around the wire, fence post, ground rod etc. We had molds that would make a Tee connection with two wires, a mold that clamped around the top of a ground rod and had the wire being welded to the top of the mold in Tee fashion, molds that had a chain clamp that held them to fence post and held the wire against the post.

The mold it self was a clam shell design that had cavities of the proper shape as listed above. There was a channel going up from the cavities to a depression on the top of the mold which had a hinged cover on top.

Once all of the materials to be welded were in the proper places in the mold, the cover on the top of the mold was opened via a hinge. A small tin (I think) plate about the size of a quarter was placed in the bottom of the depression on top of the channel leading to the cavity. On top of this plate was placed a charge of some type of black powder mixed with various types of powdered metal. On top of this was placed a small amount of starter mixture. The cover was then placed back over the charge. A flint striker was placed in a gap in the cover and the charger was ignited. Upon ignition a glob of molten metal ran down into the cavity welding together whatever material was inside the mold.

Different molds used different charges and the charge number was always listed on the mold and the charges came in different sized containers similar to old film canisters.

scott curtis
08-23-2011, 04:37 PM
thanks for all who set me on the right track..the old man who had the auction was around 90. he used it when he was young to make bullits for his black powder gun,or so he says. i thought it was unusual and i can see where the mould will work for leads, with little mods it would work ok. i think,maybe,or maybe not. but anyway thanks guys for your expertiece!!!!!

BudRow
08-24-2011, 08:45 AM
We used it on the Railroad to bond sections of rail. It is a thermite reaction that fuses a small braided copper wire between rail heads. The graphite "crusible" has a small hole in the bottom that is initially covered with a little disc of fusing material that melts in the flash of the reaction. The thermite powder is placed on the top of the disc and ignited. The hole leads to the fusing point of the rail head & wire. BudRow

1hole
08-25-2011, 08:03 AM
The point being that Cadwelding requires the mold. The powdered cad mix ignites, melds the metal (brass). The mold surrounds electrical parts and/or cables to be welded together and also forms the molten metal around the joint. It is quite dangerous for the untrained to attempt Cadwelding and its molds have absolutely no value to reloaders.

Wayne Smith
08-25-2011, 10:53 AM
Thank you Sleeper. It is truly amazing what I learn on this site.

sleeper78
08-25-2011, 01:32 PM
Thank you Sleeper. It is truly amazing what I learn on this site.

Hey, no problem. I never thought I'd be giving a lesson on Cad welding on a gun forum 8 years after I stopped building towers. I guess you just never know whats going to come up when you interact with so many different people.

Wayne Smith
08-26-2011, 12:05 PM
Hey, no problem. I never thought I'd be giving a lesson on Cad welding on a gun forum 8 years after I stopped building towers. I guess you just never know whats going to come up when you interact with so many different people.

Yeah, especially when some of them go to yard sales!