How much does it cost to get a piece of aluminum custom CNC'd? (now with pics)

Triathlon Forum
1

I created a spacer block to mount to the bed of my truck and then to a yakima blockhead and I was wondering how much it would cost to get somebody to cut it out of a piece of aluminum? I could get them all the dimensions and have already built it up in Sketch up to make sure it all works.

Its seems like a fairly basic square boxes with some reliefs and then a few holes for screws. Anybody with any knowledge of how much that costs? Who would I look to have build it, I am in Boise, ID if that helps.

If I didnt get it done in aluminum can I take it to a machine shop or welding shop to see if they might build them for me and then get them powder coated?

2

The cost really depends on how complex the work is and how many you want made. Call these guys, they work with small bike industry manufacturers and they are in twin falls, ID:

http://www.purelycustom.com/

3

The material is inexpensive, but if it’s just a one-off, then I would expect around $400.

Now that you just gasped, here is the issue. You said Cnc machine. What you describe is really a tool makers job to be done hand cut.

Depending on size and grade aluminum block, likely 7075-t651 (same as t6 but in block form instead of sheet) so the cost is about $50, again depending on size.

Cnc machine time and engineering and tooling is about $200 to $300. There is a bit of playing around when programming and possible scrap rate to include. Also tool resharpening.

Powder coat on aluminum is a bit harder to pull off as you need to magnetize it. $150 min lot charge. Maybe $100.

A shop might want to make a few dollars and also build in some padding for scrape rate or engineering issues.

However, that’s an aerospace machine shop. Not sure what a smaller shop without aerospace quality would be willing to save you. I would think not much for a one-off.

However, if your design is that simple, a mill and a drill press could make what you describe in less time and less engineering on machines that are probably not in such heavy use. Maybe $300 or less for the same product. Take away the powder coat (it’s for a truck, it will scratch anyways) and just prime and clear coat yourself, now the part cost you $200 to make and $20 to paint.

4

If you have this as a sketchup file, as a desiger and having been involved in the education sector I know this is not too difficult to translate in something like AutoCad and then output data for CNC machining. I don’t know what the culture is in the States but I would approach your local technical college if they do engineering courses and ask them politely if it would be a suitable training exercise for their students to run through. In their position for the cost of materials and you passing on a bit of praise to the students i would think this is a fair swop as its a bespoke real world exercise. It might take a bit more time to arrange than going to a specialist, just another thought.

5

Powder coat on aluminum is a bit harder to pull off as you need to magnetize it.

Powdercoating anything made of metal is the same. You hand it on a metal hook and that hook is charged. Powdercoating wood or carbon is a bit different, because of the temps involved in curing and the fact that they are non conductive.

6

The material is inexpensive, but if it’s just a one-off, then I would expect around $400.

Now that you just gasped, here is the issue. You said Cnc machine. What you describe is really a tool makers job to be done hand cut.

Depending on size and grade aluminum block, likely 7075-t651 (same as t6 but in block form instead of sheet) so the cost is about $50, again depending on size.

Cnc machine time and engineering and tooling is about $200 to $300. There is a bit of playing around when programming and possible scrap rate to include. Also tool resharpening.

Powder coat on aluminum is a bit harder to pull off as you need to magnetize it. $150 min lot charge. Maybe $100.

A shop might want to make a few dollars and also build in some padding for scrape rate or engineering issues.

However, that’s an aerospace machine shop. Not sure what a smaller shop without aerospace quality would be willing to save you. I would think not much for a one-off.

However, if your design is that simple, a mill and a drill press could make what you describe in less time and less engineering on machines that are probably not in such heavy use. Maybe $300 or less for the same product. Take away the powder coat (it’s for a truck, it will scratch anyways) and just prime and clear coat yourself, now the part cost you $200 to make and $20 to paint.

Second what prattz said. I’ve been in the aerospace machining world for the last 10 years. I’m not the machine shop, I’m they purchasing manager that manages this commodity. I fight this battle on a daily basis with machine shops. Most of the $400 cost that prattz mentioned above is in setup costs and programming the machine. Sure, it seems simple to me and you, but the programmer always makes it a harder job (IMHO) than it should be.

If it were my $$, I’d skip the CNC altogether and go to a regular old machine shop and see what they have lying around. More than likely, they have a pc of scrap that they’d sell your for next to nothing and might even trade the work off for some beer or something like that. CNC is going to look wicked cool, but for your purposes, I think it may be overkill unless you’ve got a pocket full of cash that you don’t know what to do with…if that’s the case, I hear the new P5 comes with this block already…:slight_smile:

7

Don’t let these guys scare you with their aerospace pricing. If these blocks are as simple as they sound it should be fairly easy for a guy to draw them with his CAM software and cut them for you. However, I’ve been in this business for 20yrs and I’ve seen guys come in with jobs they think are simple and are nearly impossible!

8

Yeah all you really need is a hacksaw, a file, some sandpaper and a drill press. Blocks of various different grades of aluminum can be had from places like Alro metals. I wouldn’t over think this. Just work it like you would a piece of dense hardwood.

9

Wow, I had no idea wood and carbon could be powdercoated. Thanks - I learned something new today!

10

It’s basically a 8" x 1 1/2" x 3" block that has three large reliefs cut and places for bolts that can be drilled after the fact as they are on the top and bottom.

I can upload a picture but what would you guess cost to CNC would be and how much the aluminum itself might be?

If this is a triple digit number then I may have to rethink this stuff.

11

Wood is pretty common these days, Carbon is justt getting started.

12

Why aluminum - does any manufacturer use aluminum as the material of choice for the place to mount the fork attachment?

13

I created a spacer block to mount to the bed of my truck and then to a yakima blockhead and I was wondering how much it would cost to get somebody to cut it out of a piece of aluminum? I could get them all the dimensions and have already built it up in Sketch up to make sure it all works.

Its seems like a fairly basic square boxes with some reliefs and then a few holes for screws. Anybody with any knowledge of how much that costs? Who would I look to have build it, I am in Boise, ID if that helps.

If I didnt get it done in aluminum can I take it to a machine shop or welding shop to see if they might build them for me and then get them powder coated?

There’s no reason to powdercoat aluminum broseph. Aluminum oxide works wonderfully at protecting the rest of the part from oxidation. not so bueno with salt though, so don’t drive your truck into an ocean.

14

I was more thinking about powder coating to try to match the black in the bed of my truck. Part of the reason I want to go with aluminum for this spacer is because it won’t have much of a chance to corrode like steel would.

If I needed to I might just rattle can the aluminum with black to match.

15

Annodize it maybe?
.

16

This sounds more like a manual job done on a milling machine (unless you’re talking serious volume). Figure ~$150/hr. for the shop labor and overhead. Assuming your tolerances are fairly loose (which I’m guessing they are), figure 1.5-2hrs.

Yeah, I know there’s some sticker shock there, but look at all the one-off time the shop is spending (talking with you about the job, looking over the prints, figuring out how to do the setup, getting the right clamps/tools) even before they cut the first chip.

If it’s a stock shape and they just need to drill and countersink some holes then you might be able to get the labor done for as little as $50-$75 of drill press time.

17

Here are a couple of images of what I modeled. Again the bottom length is 8 inches and the height of it is only 3 inches. The top holes are for mounting a yakima blockhead where as the bottom ones are for the bolts to a cargo rail on the inside of my bed. The larger cutout is intended to be used for a cable if I wanted to run one through my frame and through that for a little added protection when traveling.

The flat side will lay parallel with the ground face up with the hope that the bolts will be hidden and much harder for somebody to come by and undo them, If somebody really wanted to they could take the time to figure it out but I don’t think they will be able to easily snatch and grab the whole thing just walking by.

http://oi39.tinypic.com/nqcvhd.jpg http://oi41.tinypic.com/sys16q.jpg

From those images what would you estimate it to cost? Would you recommend going another route as far as materials and construction go?

18

2x4 mounted on a piece of plywood. Cost about $10 if you don’t have the scraps. Paint it if you want it to look nice

19

ehh, this will look better and will be easier to store when not used.

I have thought through this for quite some time and have decided to go this route. I already got the core-trax cargo management system installed. I need to get this spacer block made because I have a soft tonneau that when rolled up will need a few inches so as to not interfere.

20

You’ll save yourself a lot of money if you don’t hollow out the back.