3D printed hammer form

[Steve Broady]

I just tried an experiment, and since it worked out pretty well I thought I’d share with folks here.

The goal is to make some copper slant plates for a Boka style LM, but they need to fit into a stainless steel tee and be soldered in place. You can see the cross section here:

In order to make them, I decided to try 3D printing a form which I cold hammer some copper over. The yellow trapezoid in the drawing is that form. It’s also the reason why I took the time to draw this part accurately in CAD.

I printed it in PETG, using a heavier than usual wall thickness more solid infill. The result was a nice solid feeling plastic puck.

I cut two pieces of 1” copper pipe, annealed them, then split and flattened them out and cut them to shape.

I just used a clamp to clamp the whole thing to the workbench and started hammering the edge over.

I had to re-anneal them half way through, but they came out pretty well after just a few minutes of work with a ball peen hammer.

The 3D printed form worked perfectly. It wouldn’t stand up to making hundreds of parts, but for one or two it seems like a great way to do the job. A top form would be helpful, but for this I felt it was simple enough that I didn’t need to bother.

[subbrew]

Nice work. Nice to see something useful coming off a 3D printer.

[Steve Broady]

The parts fit remarkably well straight off the form.

I did a little fettling to close a couple gaps, though I suspect I could have soldered them just as they were. They fit tightly enough that I didn’t need any kind of fixturing screws or clamps, which was handy.

After a little cleanup, here’s the finished piece.

It isn’t perfect. I managed to nudge the plate out of line while I was soldering, so it’s not exactly perpendicular to the outlet. I don’t think I’ll matter in the slightest. I also ended up putting the upper plate in at a slightly shallower angle in order to increase the gap between them. I could have taken a lot more time to make the job neater, but I think I’ll work just fine. All in all, it seems like a relatively easy way to make a one-off piece, and I’ll definitely be using 3D printed hammer forms again.

[Steve Broady]

Nice to see something useful coming off a 3D printer.

I use mine for all kinds of useful things. It’s great for toys as well, of course, but I have found plenty of practical applications for it. Just one example, I made some knife holders yesterday.

They use a marble inside to wedge against the blade. Granted, these are holding toy knives in a play kitchen, but I can definitely see using the exact same design for real tools either in my kitchen or my shop.

[Twisted Brick]

Steve, great concept and execution. Creating copper flanges are relatively easy but add certainly another level of functionality/ease to a build.

Well done.

[Yummyrum]

Brilliant solution and a top job Steve .Beats cutting a a couple of slots in a SS Tee

[contrahead]

Nice work. Nice to see something useful coming off a 3D printer.

=1

[Steve Broady]

Brilliant solution and a top job Steve .Beats cutting a a couple of slots in a SS Tee

You’re not kidding! Not to mention that this way, it’s all still sealed inside where any minor imperfections in the solder joint don’t matter.. and don’t show.

Plus, as always, I’m thinking about the next project. This was an easy test to see if the idea is viable.

[Steve Broady]

Steve, great concept and execution. Creating copper flanges are relatively easy but add certainly another level of functionality/ease to a build.

Well done.

Thank you! I agree, copper flanges make a big difference. This has me wondering if I could print a pair of forms and press a more complex shape between them in a vise. It might be a good way to make a one-off custom shotgun or similar.

[OtisT]

Hey Steve. That looks like it worked out really well. Wish I had seen something like this when I built my boka. For me, sealing those slant plate joints was a royal PITA. Congrats on the successful build.

Have you thought much about the pool size (volume) you will have after attaching a valve to the output furrel? It’s been a while since I’ve read or thought about boka heads, but I recall there was a fair amount of attention paid to the pool size created by the lower plate and valve assembly. Something about wanting to limit the size of that reservoir to minimize smearing.

[Salt Must Flow]

Steve Broady, you're your own worst critic Great idea and great job! Like you said, it wouldn't matter in the slightest even if everything was lined up flawlessly. The function would be absolutely identical. I agree, I think a wider gap between plates is better than a narrower gap.

[Steve Broady]

Have you thought much about the pool size (volume) you will have after attaching a valve to the output furrel? .. Something about wanting to limit the size of that reservoir to minimize smearing.

Thanks, Otis. To be honest, I didn’t even think about limiting the size of the pool. This isn’t going in a Boka, it’s actually going to be the product takeoff for a continuous column. Although you never know what the future holds, and I can definitely see myself reusing parts in a different build in the future, if plans change.

[Yummyrum]

, it’s actually going to be the product takeoff for a continuous column. Although you never know what the future holds, and I can definitely see myself reusing parts in a different build in the future, if plans change.

I was going to ask why you didn’t add the reflux centring dick .
Don’t need it .

[Bushman]

Just saw this post. I miss the 3D printer I had in my Design Engineering classroom after retiring. We made a lot of plugs for molds. The limit of a 3D printer is with the user. I am sure other members will think of great uses for a 3D printer. I also miss not having my small CNC machine. I used it to cut parts for my Dephlagmater.