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Solsylva 25×25 CNC Router Build

 

I’ve started building a CNC router from plans.  It’s something I’ve wanted to do for a long time now but I couldn’t decide how big a router to build or who had the best design.  This article describes why I want one and why I finally picked David Steele’s 25×25-inch dual leadscrew CNC router.  It’s a popular design you can probably build for $600 to $1200, depending on your choice of electronics and leadscrews.  The plans cost $25, or $35 if you buy them packaged with two of his other CNC router designs.  They’re available on his web site, Solsylva.com.

My choice was based on at least 25 hours of Internet research plus what I learned last month at a four-day CNC Workshop I attended in Ann Arbor, MI.  There are many router plans to choose from and it was difficult to determine who has the best design. I was strongly influenced by this router’s size, its popularity and the detailed information I found on the Solsylva web site.  But what clinched it was the many helpful builder’s logs I found, many of which detailed improvements you can make.

Here are some builder’s logs I recommend:

  • Crane’s 25×25 Solsylva Build w/ Pictures – This CNC newbie built a “stock” machine and in the process he got hooked on building CNC routers.  So then he built a heavily modified version using both his own ideas and those of other Solsylva builders.

Why a CNC router instead of a bigger CNC mill

I want to cut out, carve and engrave parts that would be too big for my CNC mini-mill or even Bridgeport if I had one.  A CNC router can’t machine metal as well as a mill but being able to cut out and shape large intricate parts out of wood, plastic and foam will make it possible for me to make all kinds of interesting and useful things.

I also think members of my family will want to use it and it’ll be fairly easy for them to learn how.  They’ll be able to make signs and cut parts out of flat stock using a “2.5D” CAM program that is much easier to use than the one I use with my CNC mini-mill.  They can also take advantage of some of the many free “almost ready to cut” DXF files you can find to make things like signs, toys and even furniture.

Size matters

I don’t have room in my very small workshop for a 4×8 or even a 4×4-foot CNC router.  They would also cost more and they probably wouldn’t be very suitable for a first build.

I almost decided to build a small moving-table type router instead of one with a moving-gantry because I’d be able to easily transport it to demonstrate or teach with.  They’re also the least expensive and easiest kind of CNC router to build.  But most of them are limited to making fairly small parts.  The ones I’ve seen that could easily fit in my car’s trunk usually have a working area of only about 12×12-inches or so, and that’s just too small to be very useful.

So I finally decided that I wanted a CNC router with a working area of at least 18×24-inches because it would be able to make most of the parts needed to reproduce itself or make an even bigger router.  The Solsylva design is a little bigger than that, with a working area of 25×25-inches.  And it includes plans for a table on casters that lets the router fold down so it takes up less room when it’s not being used.  It also serves as a work table you can build your router on.  If it’s too big or too small for you then take a look at their other designs.  They have plans for three other CNC routers with table sizes ranging from 10×9 to 24×48 inches.

Cost matters too

I didn’t want to spend a lot of money on this project for two reasons.  First, if you’re a regular reader you may have figured out that “I like to spend money carefully.”  Second, I think many of my readers would like to find out if it’s possible to build a good CNC router inexpensively.  One of your biggest expenses will be for the electronics which will include 3 or 4 stepper motors, a 3 or 4-axis driver board and a power supply.  At the low cost end are some packages I’ve seen on eBay with everything I mentioned that you can buy for about $200-$250.  They include a $70 or so driver board that may or may not be junk.  At the other end of the cost spectrum are Gecko drivers such as the G540.  It costs about $250 but you almost certainly won’t regret buying one if you can afford it.  At this point I’m not sure if I’m going to buy cheap or buy good.  I’m inclined to go cheap just to find out if that’s a viable option or not.

Leadscrews can also be a big expense, especially if you want to use ballscrews on all 3-axes.  You have that option but you can also use “all-thread” or acme threaded rods.  If you want you can start with the cheapest option and then upgrade later to a better performing and more expensive leadscrew.

I wanted an all-metal router but I couldn’t find plans for one

My router is going to be constructed mostly from wood (it was designed so you can buy nearly everything you need at your local lumberyard / hardware store).  I’d rather have an all-metal router because it would almost certainly be stronger and more rigid.  Metal construction can also be lighter, cheaper and quicker to fabricate than wood, especially if you can weld.  I also wanted a metal table so I could use my plasma torch.  Unfortunately, I couldn’t find plans for one in the size that I wanted.  They exist but for much bigger routers.

However, other builders describe how to replace many of the wooden parts with metal ones.  I may follow their lead but I haven’t decided yet.  I’m curious to find out how well the original wooden design works and I can always upgrade it or build another table later.

Which homemade linear guide design is best?  I still don’t know.

In my opinion, the linear guides are the most crucial part of any CNC router because of the huge effect they have on the machine’s accuracy and the quality of the parts it can produce.  They also have a big effect on it’s speed, reliability, durability and load capacity.  And they can be one of the hardest things to fix if they don’t work well.

There are different kinds of commercially made linear guides available and they are all expensive.  Even the used ones on eBay are costly and you run the risk of buying some that are worn out or unsuitable for your project.  As a result, many inexpensive homemade linear guides have been devised by hobbyists.  I spent hours trying to find out which ones work the best and I was not successful.  Apparently, everyone’s CNC router must either work great or else they don’t want to admit that it doesn’t.  So, rather than take a gamble I decided to limited my search to the most popular and proven router designs.

Two other popular designs that can be built from plans

Here are couple of other CNC router designs I seriously considered before choosing Solsylva’s design.

  • Joe’s CNC Model 2006 seems to be a popular design.  It uses a torsion box bed that looks like it is very strong and stable.  But it also looks like it is tedious and time consuming to build, especially if you don’t already have CNC router you can use to make the dozens of wooden pieces it’s made from.  That’s why I’m not building one.  Joe has a web site now but he started out with a builder’s log for the 2006 on CNCZone.com
  • Rockcliff CNC has plans for a number of routers and you can get them all for only $20.  Their designs are also popular and they have forums where you can find help if you need it.  I didn’t choose one of their designs because their web site was harder to navigate and it had much less information than David Steele’s.  The GrumpyGeek built their Model D router and you may find his web site helpful if you’re thinking about building one of their designs.

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