Super glue and hold down related questions

[WobblyHand]

That's what's cool about this place, you learn about how different folks do things and can try them out yourself. There's really no "ONE" right way, if you get it done then you've done it right for you on that particular day....

Hope the bed gets plenty of good use now that you've fixed it


John

Thanks John for the screw idea, that was very helpful. A good lesson for me - to exploit features that need to be there anyways. There was no movement whatsoever of the piece.

What's funny is this piece isn't for me. A buddy of mine is trying to get rid of a bed and was missing a part. He asked if I knew where to get a replacement part. After scouring the internet, and finding nothing, I said, you know, I bet I could make this without much trouble... Well, it seemed simple enough.

I made the "price" enough that my buddy wouldn't ask for things like this too often. Don't want to be taken advantage of, but I did want to help him out. (He's been helpful to me over the years.) I mean, he gets to unload a bed at a consignment place and recover a little money, and some space, and I really don't get anything but experience out of it. He had to get the stock and deliver it to me. I kept any left over stock. As you well know, he got a bargain. Machining takes time, there's a lot of setup and lots of attention to detail. It's not casual work, at least for me.

But, I got something out of the arrangement, I got to do something new that I had read about with low risk to me. (Which is the major reason why I took on the task.) Practically speaking, it didn't matter if I totally failed making this piece. I'd have been disappointed, but really it wouldn't affect my life.

Got to say, S. Gotteswinter's videos are amazing. Stefan used cyanoacrylate to hold down some brackets he CNC'd. It was amazing to watch. Thought one day, I'd try that. (And I did!) That video was about building a low speed carbide grinder, which I hope to make one day. Have a motor, the disks, and most of the stock. Still have some design that I need to finish. Stefan's motor is a lot different than what I have. That's fodder for a different thread...

 

[pontiac428]

When making multiple copies of a part, especially one that you can't just drop in a vise and go, one technique is to make some fat sacrificial soft jaws out of aluminum block and mill the profile of the stock into them while clamping a spacer between the jaws so you can tighten it later. Then drop the stock into the new recess and snug the vise. Set your datum on your DRO and plot your parts. It'll be well supported, you can leave the stock proud of the fixture for facing, and if the drill goes into the jaws to make the job more convenient, nobody cries.

 

[WobblyHand]

When making multiple copies of a part, especially one that you can't just drop in a vise and go, one technique is to make some fat sacrificial soft jaws out of aluminum block and mill the profile of the stock into them while clamping a spacer between the jaws so you can tighten it later. Then drop the stock into the new recess and snug the vise. Set your datum on your DRO and plot your parts. It'll be well supported, you can leave the stock proud of the fixture for facing, and if the drill goes into the jaws to make the job more convenient, nobody cries.

As a beginner, it is hard to wrap your head around this sacrificial part/jaw idea, but it's an important technique. All I have to do is remember when to use it appropriately. Thanks for the insight.

There was a bit of pucker when I drilled through the piece into the sacrificial plate on the table. I was second guessing myself if I had accounted for the point of the drill. I took it very slow, checking hole depth frequently. The table was left unmarked...

 

[ThinWoodsman]

As a beginner, it is hard to wrap your head around this sacrificial part/jaw idea, but it's an important technique.

One important aspect of working in metal (or wood, for that matter) is having a ton of scrap material lying around. That scrap can be used to test a cutting tool, or as part of a jig or fixture for holding parts, or to make a strap clamp, spacer, etc. I built up a small hoard by visiting a few sales of machinist's junk boxes and such on CL, and ebay sets of off-cuts. Recently, I picked up a book on woodworking jigs and fixtures from Lost Arts press, and realized I need to start doing the same with wood scrap instead of just feeding it to the stove.

But back to vise jaws, if you pick up a few spares (either the raw aluminum or the pre-drilled blanks, they end up being about the same price if shop around on ebay or amazon), you can try out some different styles. An example would be to drill and tap holes for bolts and/or pins, like in a 1-2-3 block. You can then build a fixture on the vise jaw to hold your part. There is a commercial system that uses this idea to replace angle blocks: Lang-Technologies vario-tec vise jaws. This would use a lot less metal than making a completely new jaw for every special project.

 

[homebrewed]

One important aspect of working in metal (or wood, for that matter) is having a ton of scrap material lying around. That scrap can be used to test a cutting tool, or as part of a jig or fixture for holding parts, or to make a strap clamp, spacer, etc. I built up a small hoard by visiting a few sales of machinist's junk boxes and such on CL, and ebay sets of off-cuts. Recently, I picked up a book on woodworking jigs and fixtures from Lost Arts press, and realized I need to start doing the same with wood scrap instead of just feeding it to the stove.

But back to vise jaws, if you pick up a few spares (either the raw aluminum or the pre-drilled blanks, they end up being about the same price if shop around on ebay or amazon), you can try out some different styles. An example would be to drill and tap holes for bolts and/or pins, like in a 1-2-3 block. You can then build a fixture on the vise jaw to hold your part. There is a commercial system that uses this idea to replace angle blocks: Lang-Technologies vario-tec vise jaws. This would use a lot less metal than making a completely new jaw for every special project.

Those are a spendy solution! I think the cost might pencil out in a time-sensitive production application but hard to justify if it will only be used every now and then.

As a hobbyist I might consider a variation on something like this to hold oddly-shaped parts. The micro mark version may not be rigid enough for machining purposes so I'd make my own out of steel. To make it even more flexible you could get a variety of different-diameter steel rods and turn one end down on each to fit into the holes. Sacrificial jaws? Use aluminum rod for the pins.

 

[ThinWoodsman]

Expensive but probably not to bad to re-create. Drill holes in one jaw, and use two sizes of dowel pins: one flush with the jaw, another that sticks out sufficient to hold the part or fixture.

Been planning to try it out on a more limited scale: one horizontal and one vertical row of holes, where pins could be placed to hold a part at pre-determined angles. Haven't fully fleshed out the idea though.