cheap CNC machining service for short tubes etc... similar to oshpark?

What the videos don’t show you is experience and art that goes into making the chain of commands to build one part. Sure, once that file is perfected it can run fully automated for thousands of parts and get the cost way down. But it’s no easier to go through the effort to create that chain of commands and then use it only once. Unfortunately the tech does not exist to just plug a CNC into the internet and come back tomorrow to see what is piled in the bin. Very far from it.

My shop charges a $250 set up fee for a small part like that. Add material costs, tooling and man time. If you needed 1000…

If you really want something custom, you could try asking on Alibaba, as there are CNC services. If you are willing to provide measurements and a design sheet/CAD file, they would be willing to perhaps make you 10 tubes, but probably not less.

Here is an example of a partial dwg for a Haikelite MT series Extended Battery Tube for 8 x 18650, without tolerances, that is needed for a machine shop to begin planning. There can be a lot of planning involved prior to the machining process, available machine, tooling, material, programming, any engineering involvement, management, shipping & receiving, and supervision. The more of these entities that are involved, the higher the cost.

For a Machinist like me who is willing to help, can be restrained by the Workplace itself. I am not free to do anything I wish, but my last job I was given permission, even come in on the weekend and use the machines and scrap material. Finding these guys who are willing and have opportunity to do short production runs cheaply may be found on various Machinist Forums, I have never needed to search for this, but that is another option.

Our local Jr College has a 2yr Machine Shop Course and may do work like this cheap.

There may be some small independent or self employed shops that will take on jobs like these.

Full Machine capable shops will be expensive.

Keep looking.

I brought this up when I was looking for tubes myself. I never went through and asked. But check your local high school and community colleges in your area. At my local high school they will fix your car for free if you provide the parts so the students can get some real life practice. The teacher over sees everything and checks to make sure all the torque specs are right etc. Same with the machine shop they would make parts for people. It was all manual no cnc. But a high school or college has a nice sized budget yearly and won’t have the cost a private machine shop would. You could offer to buy the bar stock of metal and see if they would be willing to use their machines to give the students real life experience in machining like they will when they graduate and not just make the stuff the instructor has them make. All the upkeep and tools expense is in the yearly budget. They are cutting and filing metal down daily for different projects. They are going to go through there yearly budget or they won’t get the same amount next year.

Reminds me of being in the Marines when end of the year was coming up. It was spend spend spend, buy all the equipment ammo etc and go over budget. Because if we didn’t we wouldn’t get the same or more next year because they see it as not needed apparently.

@CNCman, how much do you think it would cost for 25 tubes? Or about 50?

Ok, say you found a shop that accepted a 50 pc order for the MF04 long tube for 8 x 18650. The Metric Aluminum Pipe is 45mm ID x 55mm OD. Standard English sizes will not fit. Roughly 6.inches long x 50 = 25 ft min @ $12 US per ft = $300 US for material, roughly.

Guessing the shop will use a small CNC Lathe with the Machinist doing all the setup and programming at the control with a working print ready to go. Figure 3hrs setup, 20 min each run time x 50 pcs = 19.6 hrs x $100 hr shop cost = $1,960 + $300 material = $2260 / 50 = $45.2 each , less Anodizing.

Roughly.

If you want a solid figure, you will need a dimensionally accurate print or 3D model of your part and present it to a shop for a Quote on the Price.

Note: It it Very Important to get the ” Dimensions Correct and Clear “on the print for a Quote. If anything is wrong, well thats not good. Its always best to get a Prototype made first and fit check it before a production run.

Also, as tolerances get smaller the price increases exponentially.

Quality anodizing ain’t exactly cheap either. Plus add knurling if required into cost?

Yup, anodizing will be ~$100 at least, regardless of how small the part is because of the minimum service charge.

If it is just for a short battery tube, you could just cut out the middle piece of an existing tube and solder the two end pieces together to keep the end threads.
Soldering aluminium is not that wizardry any more, as there are ready-made solder sticks available in good hardware shops.

https://weldguru.com/aluminum-soldering/

https://superiorflux.com/techniques-for-soldering-aluminum/

I’ve used Protolabs for work a few times. They offer lathe work, although the parts I had them make were always milled.

They have an automated system for quoting and programming, and semi-automated setup. There are limits to the kinds of work they can do, in order to remain compatible with their mostly automated process.

For small quantities, the prices can be pretty good, but it’s still more expensive than I think most hobbyists would be interested in. For large quantities, it’s better to stick with a dedicated production shop.

It’s better to source a machining shop locally and they have ability to machine your part with manual machine, a Chinese cnc machining service plus shipment cost from China to EU must be higher than $100 even for 1 pcs machined part project.