7 Axis Swiss Mill-Turn (DIY)

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You can buy rubber ball screw covers (accordion style) on eBay for $15. You need two for each axis. They come in all sorts of sizes and will expand and collapse as the axis moves. That’s the direction I would suggest over way covers. Most covers on small machines are rubber mats and we all know swarf finds it’s way behind them anyways. Used together would be ideal in any application. Nowadays ball screws can be had for so cheap i don’t see why they couldn’t be purchased in quantities comparable to lead screws. I have smaller 12mm ball screws that cost $75 shipped for 3 axis. That’s hardly an impact on the overall cost to build the machine. And the screws included bearing blocks with a double nut for each. One of the screws (10”) I paid $15 for it. I have a toolbox drawer full of ball screws at these prices because I wanted to have them on hand for projects. Besides they’re easy to cut to length when needed. I’m sure folks would’ve paid $250 more for ball screws. Curious whatever happened with this project there isn’t much online about it or any feedback from customers.

skrubol, the boxways and leadscrew nuts on this machine don't need grease or oil at all. They run fine completely dry. Metal on metal contact needs lubrication but slippery plastics like acetal work fine dry, so long as the speed is low.


Krispee, I agree on the way covers. Many machines with boxways (even modern ones) are built without way covers because the boxways don't crunch chips, and the coolant gets pushed out by the lubrication system. Everyone else with sliding way covers just has to deal with long term contamination.

The screw wipers you linked to look pretty cool. As long as the sealing lip isn't abrasive on the screw surface they would probably help a lot in a dirty environment.

Ground ballscrews with double nuts, preloaded on both ends are the industry standard for the better machines. The cheaper machines are lacking in ballscrew size and often only use a single ballnut. Cheaper machines don't have heavy thrust bearing blocks either, take Haas and Fadal machines for example.

The acetal nuts on the SwissMak are 3 inches long; this effectively cancels any small variations in screw pitch. The only way to get machine accuracy over any large travel is to comp the ballscrews with a laser and store the data set in the machine control.

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What do tariffs have to do with aluminum? Or why are they trying to buy aluminum from China? It’s junk! I buy aluminum all the time at $3/lb even Fortal and they could buy Fortal if needed. When you manufacture a machine like this you price based off retail costs and any wholesale pricing you get is profit in the bank you don’t presume you will get a big savings and find out you got log jammed. Something to be said about having business experience. Look at all the wealthy business men who have people buying disposable items and they pay without thought. It is the business man not the product that makes the business counter to what people may believe.

The 10% tariff on aluminum began in March 2018 and the kickstarter ended May 18th, 2018. The 25% tariff on Chinese Aluminum started in May of 2019, while the tariffs on Mexican and Canadian on aluminum were eliminated all together.

I'm not saying the tariffs didn't hurt, but the time line doesn't exactly add up.

I have bought quite a bit number of steppers and drivers as well as imported a BLDC in the last five years, prices in my opinion are not much higher than they were, but I'm not buying 500 of each so maybe I might not be noticing the difference.

Link to latest update - https://www.kickstarter.com/projects.../posts/2512698

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I agree with your assertion below that pricing really hasn’t changed. This looks like bad money management. Lots of things to consider when running a business.


Not sure where you are coming from I have only been supportive of the project, under funded from the start has nothing to do with me just your and his bad judgment, using the tariff thing is total Bs I'm in manufacturing and have not seen very much change that would affect a project like this, buying large amounts of material and electronics is still a buyer's market, and there are deals to be made, which will still be at a better price even with any tariff's added, I buy materials aluminum / steel / electrical and electronics parts every week so know what's up with the market

Just check the retail pricing of his materials ( not discounted ) from when he started and the price of the same items today, open your eyes