Thanks for your input, you are one of many that I have spoken with about the probotix. It?s great to have so much feedback from the people that have actually used these machines and are still using them and are just completely happy with them. This is what I am needing. I need a machine that will get me where I am going and not give up. Eventually I?ll want and get more of the machines if they obviously hold up.I have been a very happy customer of Probotix for over 3 years. I purchased a Comet as my first CNC and have never had a mechanical issue. I have replaced a few limit switches in the past but later learned that the limit switches were fine. The issue I was having was with static electricity caused by the dust collection system. Once I grounded the machine and the dust collector hose, the machine has worked flawlessly since. I follow Probotix's maintenance protocol and keep the machine as clean as possible.
The folks at Probotix are great. In the beginning when I was on the steep learning curve, they were extremely helpful and you can talk to them on the phone. Even when problems I encountered were 100% my fault, they were quick to help. I am always confused as to why I read about Probotix issues on this forum - just call Probotix!
I have made a few minor changes to the machine. I added a cross-brace under the waste board to reduce any potential deflection. Although MDF is pretty stiff, I found the brace reduced deflection and increased accuracy. I also moved the waste board down to fit into the frame vs. sitting on top of it. This added 3/4" to the Z travel.
Bottom line is that I think the Probotix machine is a great value, is very accurate and the product is backed by a team of very helpful people. My only regret is that I didn't buy a bigger unit 3 years ago.
Thank you for confirming the worries with Cab CNC. You basically pointed everything out that another person wrote about replacing merely 6 months after the initial purchase and build of the machine. I was willing to give it a shot as I have only read 1 negative review and the other 12 have all been positively. I?ve also spoken to the seller directly but of course he is trying to sell a product so the machine is top grade to him which it very well may be.I have not used or even seen any of the three machines you are considering, so the following is based only on my perusal of the maker?s websites. Feel free to ignore my opinions.
I would definitely avoid the 4x4 machine by eBay seller Cabguy2006. From what limited info is posted, it appears to be using some type of plastic roller on an aluminum v-rails for x and z, and using the surface of the lightweight box section gantry for y. In my opinion, this will wear quickly and is not very stiff.
The Romaxx machine looks more robust. It uses steel v-rails, which are much more acceptable. It appears fairly well made. I am not familiar with this brand but it does appear that they have been around for quite a few years.
The Nebula machines are popular around here, the are several owners of it and other Probotix machines who can give more informed opinions based on their experience. The probotix machines have precision guide rails which are more precise than the v-rails and probably need less maintenance. In my eyes, I do not like the gantry design and the distance the spindle gets cantilevered out when compared to the spacing of the guide rails, and the unsupported rail for z, but again, I would rely more on opinions from those who own and use them. I have a great deal of respect for owners such as @4DThinker and @honesttjohn and what they accomplish with their probotix machines, so my concerns may be unfounded. The pricing for the Nebula includes the computer already configured to run it, that is a definite plus, and is not included with the Romaxx.
I know that you listed these three, but what is your budget? I believe there are other machines in the $5k price range of these. Are you considering any other options, such as a kit? You may be able to get a more capable or larger machine as a kit. Remember that design software and bits will also be needed.
When you say ?glass? work are you referring to Fiberglas? Or are you looking to etch glass? I?m not sure any router can machine glass. Fiberglas eats bits and the dust is nasty, make sure to use good dust collection.
Thanks for the warm welcomes. Everyone has started immediately helping and it?s crazy in what has been accomplished within a week. Great forum, great community. Thanks again,Welcome to the forum,Wacky, I don't know anything about CNC,but the guys on here that have them do some outstanding projects. Some one will be along to help you out soon, this is a good place to ask questions, lots to guys who know and are willing to share with you.
Herb
Thank you for the much needed information. It is a great help to ask a question and get responses from multiple members with their different opionions based off experience. I also appreciate the knowledge that you are sharing that is important when making a big investment decision. You?ve made some great points that I?ve also talked with other members about. Thanks for your time and input.Picking a first CNC is hard since you don't know everything you want to do with it. I'm lucky to have access to several machines and brands, but not the Probotix line. Couple observations I have personally made; you want as rigid of a gantry as possible, linear rails are optimum, a spindle will pay for itself and option for best stepper / servo available.
The less rigid the gantry is, the lower speed you can cut. This will frustrate you quicker than anything else. I have a 2004 model CNC from a company out of business and my max speed is 40 inches per minute (ipm) due to the gantry and lead-screws. On two Shopbots that I have access to, the gantries are very solid and I can cut 3/4" plywood in one pass at 400 ipm and rapid move at 600 ipm. The reverse argument to that is making signs or plaques less than 16" x 24", the time to cut isn't going to make much difference.
Linear rails are optimum, but high quality v-rails are used in some of the very high end commercial CNC. With wood and plastics the linear rails are much easier to keep clean from dust than the v-rails unless they are hidden / protected.
Routers are not the best for a CNC unless you are running them at max speed. With speed control you are not getting true rated power at lower speeds. DAMHIKT It will result in broken tooling. Get a spindle as soon as you can.
After the gantry, cutting speed is also dependent on the stepper / servo motors and electronics. If available, opt for Nema 34 stepper motors instead of the Nema 27. Again, it depends on what your end use will be as to how fast makes sense. Using the CNC for 3D carving can take 50% longer at 200 ipm as it does at 300 ipm with the same tooling. Adaptive clearing at 400 ipm takes half the time as 200 ipm.
My one penny.
Steve.
Hi Matt,Anyone have experience with Velox CNC or know someone that has. Its based in California and they seem to have pretty good customer following so far and some pretty good tech support just don't know about the build of their machines as I am not inclined in this area. Ive attached a quote from them and their website, maybe someone can give me an insight. I am also considering the ShopSabre RC4 except they are around the same price but the RC4 would come with a Router instead of spindle because the Spindle is an extra 3500. These are based on all the options I am wanting to add at the moment.
www(dot)veloxcncrouters(dot)com VR5050 model
As always Thanks,
Matt
For 15K I think Probotix is a better value at a 1/3 that price. When you get up to that price you should at least get a welded frame. I have nothing against Probotix at their price point. There are better machines but they cost more $$. I would opt for a better used machine after you get it home they are all used. Some guys buy these machines and then don't use them kind of like spas. If you are patient you can pickup a good used machine for the price of a lesser machine.You can get 2 Probotix Nebulas for that price, even if Mike doesn't like them.
That Spindle price and add ons sure seem expensive.
That's my .02.
4D can give you a better breakdown.
