How would you make this, and how much?

[tech413]

My stepfather works for the city. He brought this key home and asked me if I could make it.

They are just used for opening garbage bins for pick-up. The current ones they use are made from cheap cast white metal and break all the time.

They want a quote for 12 of them. I have an idea of how to make them, but I want your guys opinions and how much you would charge.

Thanks
Adam

[johnptc]

$85 an hour plus material


i would use round stock slit the end and braze in the cross bar and drill it out

[Mike Ameling]

It's always amazing the amount of time a little ... tinkering ... project can eat up.

So figure your "shop rate" - whatever is normal for your area. And then I would say double it.

But also remember some of Francis Whitakers advice on what to charge. For every hour of forge work, there is another hour (or more) that you spend on all the other parts of the business that you cannot directly charge a client for.

How to make it? Hmmm ... take a long high-carbon bolt. Grind/file off the sides of the bolt head leaving those wings. Then drill out the end. Then heat up and forge out a loop or T handle out of the rest of the long bolt. If the bolt is long enough to begin with, you can clip off any threads before forging. But you should probably anneal that high-carbon bolt first. Just choose your original bolt so that you have enough metal in the head for the key "wings", and that the shaft isn't too thick when compared to the original key.

Keys like that get cast up because it is the quick/simple/cheap way to make them. Now, if they would cast that key out of GOOD QUALITY STEEL to begin with (instead of "pot metal"), they would have fewer problems.

Hmmm ... another possible idea. Have a flexible rubber mold made up to make wax duplicates of that key made - for that Lost Wax casting method. Then have a steel foundry cast them up using a pretty good quality steel mix. When you get them back, clean up any casting flanges, smooth them out, and drill that center hole to true size. Gunsmiths have small parts cast up like this all the time. And if you are kind of good at carving wax, you wouldn't even need to make that flexible rubber mold to form the wax blanks.

Other options would all involve heating larger stock, forging, upsetting, fullering, drilling, and more grinding/sanding to finish.

Hope this helps spark an idea that will work for you.

Mikey - that grumpy ol' German blacksmith out in the Hinterlands

Edited April 3, 2009 by Mike Ameling
bad spellin

[Mike Ameling]

Also go down and visit a couple antique/junque stores/malls. You would be surprised at how many KEYS they often have - and in many many varieties. You might find some that would work. Also check with a locksmith. They might have blanks (or old keys) like it that can be ... tweaked ... to work.

Mikey - that grumpy ol' German blacksmith out in the Hinterlands

[ThomasPowers]

Forge the loop, tig weld the wings, drill the hole. Normalize!

[Frosty]

I'd build it from black pipe, bent 1/4" rd handle and welded ears. 4-5x $ cheap cast item and give then a lifetime warranty. PROVIDED I can find pipe that dimension without breaking the bank. I'd estimate a couple hours making the jigs and maybe 10-15 mins building the keys.

Don't worry about the warranty, they'll lose them before they break them. And yes, I'd repair or replace one that got run over by the garbage truck. PR counts and these would be real quick to build.

Frosty

[dief]

Find out if you can subsitute a "T" handle instead of a loop. If so, this would simplify/speed up the construction. Look to see if you can find some thick wall tubing that matches the size of the key. If you started with longer wings then needed it would be easier to mount the tube and two wings in a jig. Weld the wings on and then cut off the excess.

[j.w.s.]

What about starting with a piece of square or octagonal stock, lathing down all but the ends to the needed dimension. Finish the wings with a small grinder/ wheel/ file. Drill the hole to the needed depth and diameter. I'd just flatten the other end and punch out a hole for a key ring. Clean up, heat treat and viola! If you can get a system down, 11 more should be rather easy to knock out after the initial prototype.

[tech413]

Maybe I should have noted that I do not have a lathe.

[j.w.s.]

No lathe? I usually use moments like this for the 'well dear, if you expect me to put more food on the table this week I just have to buy a ____________' speech. :)

[tech413]

LOL, I want to buy a lathe, but there's lots of other stuff I need to buy first. I have access to a lathe tho.

I made a prototype from a grade 8 bolt like Mike Ameling suggested, it worked well. I sent some bolts to be drilled by my old shop teacher from high school. Grinding the heads down to the right shape only takes like 5 minutes each. I'll just forge and weld on handles.

My other question is, what should I use to finish them so they don't rust?? Paint seems to wear off them quickly. Would linseed oil work, or should I use something else?

Thanks for all the responses so far guys!

Adam

[Iron Falcon 72]

I doubt they'll have time to get any significant rust. Linseed oil or beeswax should be enough.