Welding a Collar To S7 Tooling

[knots]

Ok, so i understand that the proper way to weld a collar onto a piece of S7 screw press tooling is to use 4150 collar material and welding rod using TIG, Proper pre/post heating of parts is a given. Unfortunatenately I currently have only mild steel collar material and a mig welder.

My question: Is it a fools errand to use my available materials, with preheat and post heat ? This is for my own use and a failed weld would not likely be more than an inconvenience.

If anyone knows something of the science of this combination I would like to understand the whys . Always interested in learning so any information will be much appreciated.

 

[knots]

Bad Idea ?

Ok so no reply . I assume that this is a really bad idea. If so I will just Silver Braze for a temporary fix.

It would be helpful though to know where on the scale of bad ideas this falls.

 

[Mick - Ford Focus]

That's Not Much Of A Welcome Is It.

knots

Not A Clue On Your Question But I Feel You May Have Answered It Yourself If You Re-Read Your Post. That Maybe Just My Take On It As I Have No Clue What Your Trying To Do.

Never Mind Welcome To The Forum. Stick With It The Experts Will Turn Up. . . Honest.

A Piccy Would Help Me Understand (Possibly) What Your Trying To Do.

Mick

 

[hotrodder]

As Mick said, post a pic or two to give us something more to go on... are we talking something smallish like a flypress or a huge screw press. Assuming the collar is just for tool location and a failure would just be an inconvenience then i'd pre and post heat and go for it.

4150 is gonna be much closer to the S7 properties wise than mild steel- harder, stronger, tougher. How important that is depends on the job the collar is doing

 

[knots]

Thanks Guys

The screw press is an old Waterburry Farrell w/ 2 3/4" Dia. 2 start screw. Weighs about 1700 pounds but I am an old guy and don't drive it all that hard.

The slitting chisel to be collared is 7/8" Dia. that I will be using to slit 1 3/4" 4150 hammer blanks for handles. Not a production run. Just a few hammers for friends, and the smaller slitters for a bunch of walking canes. Who knows what then.

The collar is to keep the butt end of the slitter from bottoming out in the tool holder and mush-rooming. So the collar will be in shear. I know that silver will be plenty strong up to an unknown temperature. Un known because I really have no idea of what the shear stress will be on the collar. But this is hot work so the hammer blank will be at near yellow heat.

It is just that Migging the part would be so much easier because of my ongoing move. Also I would not have to worry so much about the brazed joint over heating.

It will be a few days before I have access to a computer again but will check back ASAP.

Many Thanks.

 

[Mick - Ford Focus]

knots

Right Understand What Your Getting At Now - Not My Field At All.

I Guess Mig It And Give It A Go - And Stand Clear In Case....

Mick

 

[Tino]

I would hire/borrow a stick welder, find half a dozen 309 or 312 rods on ebay and weld it with them.

 

[Mick - Ford Focus]

Tino

Was Gonna Ask Why Stick But Guessing Thickness Of The Tool At 7/8" Dia. - Would That Be Correct.

Mick

 

[Tino]

Cost. M.I.G would do the job but, a reel of stainless dissimilar wire and gas (argon) would be very expensive and you would only use a very small amount so you would be left with most of it unused. Half a dozen 2.5mm or 3.2mm rods will cost about 3 or 4 pounds. Job done. Piggy bank still in one piece.

 

[Mick - Ford Focus]

Tino

Aha More Learning - Love It

What Is "dissimilar wire" - Seen It Mentioned A Couple Of Times And

MIck

 

[Tino]

It's a stainless steel (wire, or rods) for welding different steels together (dissimilar steels) like stainless to mild steel, tool steels and other difficult to weld steels. There are several different grades 309, 312etc but they are quite similar.

 

[Mick - Ford Focus]

Cheers Tino

Simple As That Then.

Another Snippet Of Info

Mick