Anyone offer good ideas for or to make these?

DMS General
1

I have a test project under development and need guide blocks something like the attached photo. All are 0.5" thick x 4.25" long.The holes are 1.625" from one end. Through hole is 0.25" in diameter, the counterbore is 0.375" in diameter by 0.325" deep.

These are guide surfaces for router bit bearings to ride against, so need to be hard and durable aluminum or plastic. Ideally, these would be produced in sets containing all these sizes and with these quantities:
40 blocks 0.375" width
30 blocks 0.5" width
25 blocks 0.625" width

Prototyping with wood, but want a final design that does not swell/shrink with humidity.
Need low cost that meets specs:

What material other than aluminum should I consider?
What making process is a good fit?
Would any Makers be interested in being a supplier with the expectation of repeat business?

Guide%20Blocks
Guide%20Blocks1541Ă—914 56.9 KB

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Sounds like the perfect application for the HAAS & some fixture plates.

1 Like
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At one time with the correct endmill we were allowed to use the MultiCam to machine plastic. That seems like a good combination.

I believe the Shapeoko can be used to machine plastic.

Have you considered 3D printing (PLA) prototypes? Do you need prototypes?

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First off, I wouldn’t do the .375 counterbore on a .375 wide workpiece. Even your model shows it breaking thru the wall. It will be sharp and even with a tolerance of .005" you’re probably going to get an uneven breaking of those walls. I would do a spiral ramp into that counterbore unless you’re using a reamer.
Delrin is a hard plastic but it’s still going to flex on you. Personally, I would hold these in a vise and cut them all from the same width material (.75 wide). Cut the profile to the corret width, and the holes. flip them over and cut the flange away to the needed depth. Rinse and repeat.

5

Yep, I considered just showing that milled away instead of a counter for the 3/8" width and probably should have.

Delrin … I agree, it’s bit too soft. I was thinking that whatever is normally used for dominoes would be a possibility.

With a bit of experience, how many of these could one turn out in an hour?

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Not in my wheelhouse, so looking for input for production, not prototyping. Wood is fine for the protos.

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A quick Google reveals that Nylon might be a good choice.

“Acetal Copolymer + 30% Glass Fiber” and “Polyimide + Glass Fiber” also popped up as possible plastic choices. I presume “glass fiber” would be rough on endmills.

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I’m curious how this is used with a router and how only one mounting hole is needed? Are you using both sides as a guide, there’s usually some slop if using a threaded bolt to mount, might consider a shoulder bolt. And skip the counter bore if you can live without it unless you are using cnc, otherwise you are in for lots of tool changes.

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Polycarbonate would be my go to for a mechanical application that wanted a harder plastic.

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I think dominos are usually made from Acetal. I wonder if Acrylic would work? If so, easy to produce those parts en masse from an appropriately thick sheet on the multicam…

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HDPE? It’s relatively easy to buy, or if you wanted, you can make blocks from old milk jugs

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A spiral ramp is slow, so depending on how you do and how well a finish you want off the machine, i’d say no less than 3 an hour.

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I’ve sent you a message. I have plenty of time on my hands.