Senior Member
If you buy the Alpha you will get a good mashine that will do the job if you dial in your feed speeds and have the right cutters. I have an alpha and I am happy with it .
Where are you located ?. See if there is anybody with an alpha in your neck of the woods and check it out .
Member
Stephan,
I am in Lithuania. It means that I can rely only on ShopBot support and on the advices from forum.
Yes, I understand that the feed speed as well as the spindle RPM should be done according with material which I will cut and with the task, which I will want to do. From previous posts in this thread, I understood that some people was not happy with cutting quality of the their tools, and they began to modify machines. maybe it concerns only of old ShopBot machines? maybe all new Alpha machines are fine as well as its software?
Senior Member
Elijah,
I'm sure that a lot of Shopbotters anywhere in the world would be willing to cut a part for you and then either post a photo of the cut or email you images. I will be happy to make a test cut for you, but my machine has been altered with a 3:1 belt-driven gearbox.
I'm attaching a GIF image of a test that I designed that exercises the Alpha in the areas that I was having problems with before I added the 3:1 gearbox.
15482.gif
I would be happy to email anyone a DXF file and the SBP file that I used to cut the test. The size of the test is 12" X 12". Cutting it out of MDF only takes a minute and, I would imagine, allmost every shop has a small piece of MDF left over from other projects that they could use to run the test for you.
Senior Member
One thing is puzzling me.
My PRT, which I have been very pleased with, consists of table, x rails, y gantry, z gantry, 4 stepper motors and associated cables, control box and software, including Part wizard.
The table I made myself.
I use AutoCad not PartWizard.
I can buy stepper motors of the shelf, and cabling.
The ascension 1000 makes my PRT almost an Alpha.
Mach software allows me to use industry standard G Code.
So all I am left with from the ShopBot are the x rails (which I can purchase elsewhere,) the y gantry and the z Gantry.
I do have ShopBot support for when it breaks down though.
Anyone got spare x rails, y and z gantrys going cheap?
...............Mike
Senior Member
Elijah, if I were you I would buy the PRT Standard instead of the Alpha. (I live in Africa). If you place your order now, your shipping date will only be in November (or later) and then the Standard should be shipping with Gecko drivers and geared motors. This will give the same results as the Ascension, and the cut quality will be better than the Alpha of today. Maybe not exactly as fast as the Alpha, but close. It will cost less and use less electrical power.
If you find that the millimeter version of the software doesn't work for you, or if you have problems with computer communications etc., you can convert the control to Mach3 for probably less than $200. Then you will have the choice of support from either the ShopBot, Ascension or Mach forums, and your machine will be similar to other Gecko machines already in Lithuania - somebody there will understand it, and you should have a good re-sale value there.
Senior Member
Mike, I have those bits lying around the shop - come and collect.
Senior Member
Mike J.,
You've nailed the problem pretty good. It all comes down to service and software.
Shopbot's service is unparalleled. Their forum lets any 'botter help any other 'botter. Opinions and tips are freely posted including most that would be critical of some aspect of the machine. Sometimes some of us get a little carried aways with our posts and the forum admin helps us avoid serious embarassment by deleting something - I've had that happen to more than one post - but they're a lot more tolerant than any other forum that I've visited.
Everytime I've called Shopbot for help, I've gotten help - and everytime that help was exactly what I've needed. Everytime I've emailed, I've gotten a reply that solved or helped to solve the problem - including several emails from Ted who personally gave thorough answers to my questions. I don't remember ever needing parts from Shopbot, but they've had every part that I've ever asked them about - on hand and ready to ship. To me, that is excellent service. I don't know what I would expect more than that.
Their software is easy to use - period. Whether it is industry standard or whether it is not doesn't matter to me because I can use it to do the things that I need to do. I have G-code. I know how to use G-code. I also know that G-code has built in features that are lacking in Shopbot's code, but I still use Shopbot's code. It works for me and it works very well.
Except for 'chatter' the Alpha that I have has surpassed my expectations. It is fast. It is sufficiently accurate to do what I need to have done. It is robust. It is simple to maintain and repair. Did I mention that it is fast? It is fast. I found a way to solve the 'chatter' problem by adding a 3:1 belt-driven gear box. Brady mentioned that Shopbot now offers an excellent gearbox to anyone who purchases a new Alpha and a retrofit to existing customers. In my opinion and with my experience using the Alpha, I'll go on record to plainly and loudly state that the Alpha needs a gearbox or you'll have excessive 'chatter'. Adding or buying a gearbox is not a big deal. Although I don't know what a gearbox costs from Shopbot, building one yourself won't break the bank - and it turned my machine into a real CNC router.
Everything else that you posted is perfectly valid. Parts and pieces to make or modify a CNC router can be purchased from a lot of different places - but who's going to hold your hand while you assemble your machine. Who's going to help you cut your first parts? Who's going to rush to your aid when you realise that you simply don't know what to do next?
I would suggest that anyone contemplating entering the CNC router world first buy a Shopbot. Learn how to use it. Learn what it can do. Learn what it can't do. Then, if your needs fall outside of what a Shopbot can do, sell it and buy something else. For the money spent, I can't find anything else on the market that even comes close. Right now, if I were to need a second machine, I would buy, at the very least, the complete machine from Shopbot without electronics of any kind and then add those parts and pieces that exactly fit my needs; but, remember, I've built process control computers for more than thirty-years so messing with the electrical part of a machine is something that I have done and enjoy doing. I don't recommend that anyone else try doing that. It could very well end up costing you much more, both in time and money, than buying everything from Shopbot.
Shopbot has a good machine - no - Shopbot has a great machine. If it can't do everything that you need it to, it can be adapted or modified until it can do what you need it to - unless you just have to have one of the big-iron machines that cost 10X to 30X more than the Shopbot.
Senior Member
Other Mike
I agree 100%
"I would suggest that anyone contemplating entering the CNC router world first buy a Shopbot. Learn how to use it. Learn what it can do. Learn what it can't do. Then, if your needs fall outside of what a Shopbot can do, sell it and buy something else."
It's when you realise what is possible, and what isn't possible from Shopbot, that you start taking notice of these, for me, complicated posts.
...........Mike
Senior Member
One of the interesting character traits that I have is that I find it really easy to blame someone else for my problems. Back when I was having problems with my 3hp Colombo spindle, I called Shopbot a few times to see what to do. They gave excellent advice. The spindle still didn't work right. I called PDSColombo. They gave excellent advice. The spindle still didn't work properly. As one point I started checking my family tree to see if perhaps I had an uncle Luigi, who drove a big black car and who liked to carry baseball bats when he visited with people, who might be willing to visit Shopbot for me and politely ask why they sold spindles that didn't work. As you all know, it wasn't Shopbot's fault. It wasn't Colombo's fault. It was my fault. I had modified my computer and added a wireless network card that interrupted operation of the software. It was my fault. But, during my problem, Shopbot went out of their way to try to help me. Of course their solutions didn't work for me because they had never had to deal with something that I had created before. How could they solve my problem? But they tried.
The other major problem that I fought for two full years was 'chatter'. I've posted photos of the 'chatter'. Others have posted photos of 'chatter'. I talked to Shopbot about the problem. They again tried to help. Nothing worked. Nothing. I checked rollers. I cleaned rails. I removed and inspected spur gears. I played with ramp speeds. I tested every kind of cutter that I could find. I examined the mechanics of the Shopbot's design. I called Bishop-Wisecarver and talked to their technical people to see if I added their rails or more rails or bigger V-rollers would work. Finally I realized that most PRT owners didn't admit to having 'chatter' problems. I thought, "what a conspiracy. They've all gotten together to get their revenge on us Alpha owners by denying that they have chatter problems." Then, after thinking and pondering and thinking some more, I realized that most PRT machines were geared. Then, I called Oriental Motor to order gearboxes for my Alpha motors. They couldn't help me. Either you bought Alpha motors with the gearbox already attached or you bought or built your own. Sorry. That's just the way it was. So. I built my own belt-driven 3:1 gearbox. Then I built version two. Then I built version three. Then I built version four. Now I don't have chatter. There was nothing wrong with the rails. There was nothing wrong with the rollers. Their was nothing wrong with the basic design. The Alpha motors just had to be geared down to give proper operation on my machine.
The important factor in all of this is that Shopbot tried and tried and tried to help me -even when it wasn't their fault. When it was their fault (at least I'll call it their fault) they still tried and tried and tried to help me. Because they tried and tried and tried, I really admire them. There are issues that I don't agree with. Many of you have read my rantings about those issues, but that does not mean that I would buy from anyone else. Some of you may have read my postings about the Ascension box. I like it, but I don't own one. You also know what I've said about G-code. I like it, but I don't use in on my Shopbot - and I don't think it is the coding language that a new CNC router user should have to use. Maybe I've underestimated the ability of new CNC operators to learn new and complex things. I don't think so. My memory is going fast, but I do remember wondering just how long learning to use a Shopbot would take - and that was with their easy-to-use language. I don't have a PRT, but if I did, I would be talking to Dirk right now to order his Agek. He's built a good box. He's built the box the way that I would build a box. IF I found something that I didn't like about his box, I would be calling Shopbot to order a G4. It's nice to have a choice. It's nice to know that there are options available. It's nice to know that I'm not doing this alone.
By the way, does anyone really think that Thermwood or Komo or any other CNC router has no problems. Does anyone really believe that buying a big-iron CNC router means that a service tech drops by twice a month just to see if everything is working - at no cost?
We Shopbot owners have got it pretty good.
Member
Gerald_D, is this mean that PRT now is better than Alpha? What for then was created Alpha? I always thought that Alpha is created for more precise and fast cutting, carving etc. In other words Alpha should do the task better than standard PRT. I am completely confused. I do not have goal to save a bit of USD. I am keen to buy good tool, if we talk about ShopBot tools. What I should do then...
Posting Permissions
