Buddy 48 or full size ShopBot

[ajf]

I’ve been following the forum quite closely since the introduction of the Buddy 48 and the power stick, largely because I think it might meet my needs. There appears to be enough people out there now using this combination that I was wondering if you have any comments regarding whether the Buddy 48 and power stick combination has met your specific needs or not. Or if you had wished you had gone with a full size table model instead. Most of the time I think the Buddy 48 is large enough to do the things I want to do, but at the same time I know I will want to cut a 4x8 sheet of material every so often. Can the Buddy in combination with the power stick actually come close to doing what a full size table offers when cutting larger material or is it expecting too much?

[dana_swift]

Howdy Al- The powerstick is an amazing approach to making a CNC router able to handle various size jobs with a single machine.

Some simple facts: the powersticks work. I have two of them one 8' and one 4'. From your comment about cutting large sheets "every so often" your expectations may fit the powersticks realities.

I have one of the first generation Buddies, and with that I have the "slab of aluminum" 2' table. That configuration is capable of getting results I think compare to a gantry router.

Normally I run the router with just the 2' table. Occasionally I use the 4' powerstick, and rarely the 8' powerstick. The reason is the powersticks take a lot of room, more than twice the size of a similar sized gantry router. Keeping the "motion footprint" down makes the router easier to work with, so I only use the powersticks when the project size demands them. Just as you imply you intend to do.

Whether the Buddy/Powerstick options will meet your needs is a question you have to answer. The combination is not a replacement for a gantry system however.

Another fact that cannot be overlooked is with a gantry system the operator is always standing outside the motion envelope. The router moves to "home" which is one of the corners for tool changes. It cannot move to where you are. With the powersticks the table is capable of "reaching out and touching you". When I am using a powerstick I do not stand around the "open side" of the table and watch the machine cut. That is normal operation with the 2' table or a gantry router.

A full size gantry system can be expected to be equally accurate in Z over its entire bed. The powerstick approach depends on your installation and operation to get that level of consistency.

In my opinion if you intend to process gantry sized projects as the "normal" case, buy a gantry system. If small projects are the norm, and large ones happen occasionally, powersticks are perfect and allow you to get started with a smaller router and add length capability when there is a customer to pay for it.

And one other note- shopbots are amazing tools, more amazing when you consider the price. However its easy to save pennies and waste dollars. Buy the tool size the job requires. It should be obvious from reading the forum that those of us who spent our money on shopbots are glad we did. Sooner or later you need customer/tech support. In my experience Shopbot excels. I suspect you will discover the same thing.

Good luck-

D

[erik_f]

Depending on the size of the table and options you are looking at a 4x8 PRS Standard is the same price as a Buddy 48 Alpha...

[harryball]

Al,

I've used the Buddy 48 and I have a 4x8 PRT Alpha. The power stick is a great option for the Buddy but it does not replace a gantry machine. If you are going to be cutting 4x8 sheets as a regular practice I don't believe you'd be happy with the power stick. If, however, the majority of your work is 4x4 or less and you will occasionally need to handle a 4x8 sheet it's a good option.

The power stick also does a great job for cutting certain odd jobs, like fireplace mantles etc...

/RB

[erik_f]

If the buddy were made the same way it was when I bought it...with the aluminum table, and was the same price...I would say go with the buddy48...but looking at the prices now and construction of the Buddy now...I would really look at how the new Buddy functions compared to the older aluminum table style machines. Now I have had NO experience with the new style powerstick only machines, but they seem to be made lighter than the machine I bought. On the other hand the implementation of the powerstick on the newer machines do seem like they would be more stable than the powerstick I would be able to fit to my machine. The power stick for the newer machine seems to be an improvement over the first powerstick design...but in a way it almost had to be since it is the only "table" surface used. The original BT was designed to be a small format machine and the powerstick came in as an after thought and a retro fit. The newer style machines are designed AROUND the concept of the powerstick as opposed to the older machine being designed around the total concept of the larger PRS machines brought down to a smaller format. I am not trying to turn anyone away from the BT series since in some ways I really like the way the powerstick works on the newer machine, but with that said as small CNC tables go...I'm glad I ended up with the aluminum moving table as I think accuracy trumps flexibility. I don't think you can get the same accuracy out of the current set up. Like I said in the beginning...I have had no experience with the new style machines. I read some were that Shopbot is offering a phenolic table top to bolt onto the 2' powerstick that comes on the current machine, and maybe this cures any of the stability issues that the new style may lack from the deletion of the sliding chunk of aluminum. Its late and I hope I didn't piss anyone off, but I'm going to bed without proof reading this...so sorry for the poor English and typos.

[mikeacg]

I can't see where the PowerStick would be any less accurate than the table is. It uses the same drive system so any side-to-side movement should be the same and with the roller system there appears to be no flexing of the sacrificial board.

Mike

3599

[erik_f]

Like I said, I have had not used one of the newer machine or powerstick. I am only basing it off my experience with my BT48 and PRT96. The aluminum table has a roller on 4 corners that hold it down and up. For example if I were cutting something with an up-cut spiral and it was firmly attached to the table top, on the powerstick there is potential for the material and table to be pulled away from the rollers, where as the older aluminum table is fixed in both directions...so no upward movement. I'm just saying there is more potental for undesired movement on the powerstick set up. I'm not saying its a bad set up to use. I've been within a heart beat of ordering one for my machine a couple of times. The original poster wanted to know the differences and I am just trying to give him the best idea of what he may be getting into. I know for a fact that I would like my Shopbot to be more accurate. As I have gotten more and more comfortable with CAD and using the machine some of my projects have gotten more and more esoteric. So .010" isn't a big deal on some things...but on others it can make things a real pain. So it really depends on what you want to do...but I didn't know I wanted to do some of the things I want to do now. I'm glad I can eek out parts within .004". I was not trying to start a debate on mine is better than yours. I think both style machines have there strong points. My opinions still stands though that the older style bt is going to have less potential for accuracy issues than the newer machine...and that if you want easier accuracy then realize that the BT is not the same machine that most people have been posting about on the board, the design has changed. In some ways for better and in someways, in my opinion, for the worse. The fixed table machines will be the most accurate and I think the older buddy was on par with these.

[myxpykalix]

Al,
I don't have a small table, mine is 60x120 with an indexer bay for turning columns. But i have to say that probably 75% of everything i've done so far (other than columns) could have been done on a 4x4 machine.
I tend to think "bigger is better", so this gives me the option to throw a 4x8 sheet of plywood on without having to move the indexer.

The downside is when i built my shop it wasn't with the idea of having a shopbot so other tools have been pushed aside and i can barely get around in my shop.
The upside is now i have a good excuse to build a bigger shop!
You might think, "well i just want to make small items like...xxx" well you will find people will come to you and ask if you can do things you never thought of doing on your bot.
In the end i think it will be your budget and space that dictate the model you get. Good luck.

[ajf]

Thanks everyone for the comments so far. Until Erik mentioned the change in the table design I hadn’t actually been aware of it. So when I looked on the documentation site I noticed the new Setup manual was now listed. Having read through this and compared the pictures in it with other postings; there is some definite design changes and visually the new design seems a bit less robust than the original design, though I can’t verify that without some technical specifications that actually compare the two table designs. I know with my present CNC one of the big issues I have with it is table movement. Some of the smaller things I have been cutting on this machine require an accuracy of +- .005”. So I guess that brings up the question could I expect that type of accuracy from either the Buddy or from the full size model with the same consistency.

[dana_swift]

Al- Accuracy really depends on your skill with the machine. If your material moves 0.050 inches during a cut, that will be your accuracy.

The bots are VERY repeatable in the order of 0.001 or 0.002. If extreme accuracy is required, I make a part, adjust the toolpath and then get what I want.

A good way to judge the repeatability of the machine is to look at the edge of a cut where the machine moves all over the place then comes back to continue deepening a cut. How far is if off from the previous pass? It is very very little.

The qualities of accuracy and precision are separate concepts. If you need a given precision within a given accuracy the best thing you can do is go locate somebody with a bot and try your part on it. Very little money to spend, it could protect your investment pool, and you can make a friend while you are at it!

D

[gordon]

The considerations we most commonly discussed when asked which machine is best are; how much space is available, what does the budget allow and what is the intended product, will it be a specific product that only requires a smaller machine or will the tool be used for a more diverse selection of products or be a larger size for the most part. These are the most typical considerations in deciding which form factor is best when purchasing a ShopBot, whether it be a full size PRS or a Buddy.

The Power Stick was originally a part of the Buddy design. In fact, the first few shipped had guide bars with power stick wheels and ball rollers, as well as, cam handles for releasing the table so a power stick can be installed. Unfortunately, fabrication of power sticks wasn't up to speed before shipping these tools and the power sticks had to be made available later. The latest Buddy tools were designed to improve upon these tools by making them much more rigid than their predecessors. One way this was done was to use a single sheet of 1/4" steel for the main deck instead of many individual parts bolted together that required lots of finessing to get them aligned properly. This also had the advantage of using laser accuracy in cutting of holes for the power stick wheels and other critical parts. These changes made the alignment of the power stick much easier and reliable by removing the many variables that multiple parts created. The new deck also allowed us to add rollers to the center under the cutter instead of just the outside edges, providing much more support surface. These rollers support the work holding surface better by spreading the load out and help to prevent the surface from being pushed down when plunging or pulling it up when using an up cup spiral. Another big change was to go to a power sitck that is 3 times wider and almost twice as thick. This allowed the wheel base for the power stick to be increased considerably and providing a powers stick with a higher load capacity and more surface to mount the work or work surface to.

Other changes include changing the orientation of the power stick motor, making it more rigid and unlikely to twist under load. The cam handle was simplified and the release handle moved to the side of the table where it is easier to access without having to reach under the table plate or power stick to get to it.

We still have Aluminum plates and Phenolic plates for those that want a support surface that is really rigid in a 24x32 or 24x48 format for their new Buddys.

Hopefully this describes the differences between the first and second generation of the Buddy tools. Any further feedback, observations, comments that anyone would like to add are welcome either here or emailed to me.

[ajf]

Thanks for the responses this is a great forum and definitely a strong plus for going with a ShopBot.

[erik_f]

So Gordon,
When do the old Buddy owners get the option for the 1/4" steel plate upgrade
ha ha ha

[harryball]

Al, seeing on in person is really the best way to get a feel. Good luck with your decision and keep us posted.

[dana_swift]

Gordon- Your statement: "... the first few shipped had guide bars with power stick wheels and ball rollers, as well as, cam handles for releasing the table so a power stick can be installed." Is clearly false.

I own one of the first buddies, and it had NONE of those features. I have the photos to prove it. It is a great machine, but the ability to accomodate a powerstick was clearly sold as an "option".

If you wish to make that statement, I would like a refund for the extra cash I had to shell out for the missing features that were supposed to have been part of the product. Check the ledger.

D

[jharmon]

Gordon,

Can you post a picture showing this 1/4" steel deck configuration? I am curious as to what that's all about.

Also, the remedy for the PS motor twisting problem sounds very worthy. Are older buddies able to employ the new wider/thicker PS and motor setup as an upgrade perhaps?

Thanks for all the great info
Jim

[erik_f]

When I bought my BT48 the PowerStick was still under development. As far as I know the first Buddies that came off the line didn't even have the steel punched on the cross member so the guide block would fit it. So I'm with Dana on the idea that the first few shipped with the powerstick guide block installed as I believe mine was also one of the first production BT48's and there was no guide block or cam installed. These posts aren't meant to hang anyone out to dry...but I directly asked if there were any planned major design changes planned for the BT in the near future. The answer was a "NO" with a laugh at the suggestion of the idea. I was willing to wait if there was any changes going to be made...but again I'm quite happy with my machine and the price I was able to get it for. When I purchased my BT48 the price was $5800. I guess I shouldn't gripe.

[ajf]

I would love to see a ShopBot in action but the long and expensive drive or plane ride out of the Yukon Territory makes it hard to justify. I purchased my first CNC based on budget and available space, but in the end what I really found I should have done is based in its ability to live up to its specification and what type of support was available. Having said that, it was purchased as learning tool and I definitely learned a lot, but I’m just as happy the company I bought the machine from has since gone out of business and no one else would have to deal with the frustrations I experienced with that company.
My background is in engineering and computer sciences, and I would like to think that when I research CNC machines I know when good technical information is being presented or not, but also an active forum adds a lot of benefits to that research. So what I found over a period of a year now, looking at many different machines is I keep coming back to ShopBot. There is also another reason for this: I’ve been using VCarvePro, Cut3d, Photocarve, Mach3 and soon Aspire for several years and really like this software compared to the 2 other Cad Cam packages I have purchased and learned, so going with ShopBot also makes a lot of sense to me from this aspect.
Budget wish I can afford either, space wish I have the room, but would be giving up some assembly space permanently if I went for a full size table. Work table size: most of what I like doing could be handled on a Buddy 48 however, I do get requests for interesting work that requires a larger work surface every so often, that I really hate turning down because I would just like to do it (cutting boat panels for Stitch and glue construction or a large sign). So if the Buddy can provide the capability, and the accuracy to do what I want when it comes to those lager pieces it would be the best option for me. I’ve seen pictures on the web of some of things being done with the powerstick and it sure looks like the precision that I need and could live with is there, but I would like to still hear from the people who have used the powerstick and the Buddy to see if they are satisfied with the results they are getting.
Thanks again for all your responses.

[ted]

Hello All,

I don't really have much to add to this thread (and probably should not even jump in) because I believe there are a full range of appropriate and helpful points that have already been made. In particular, as stressed by Dana and others, a Buddy is not a replacement for a gantry tool if your primary purpose is to do panel processing. It would not be an efficient use of space, and even with outfeeds rollers, a Buddy does not offer the same robust support as a grantry tool. This may become particulary significant if you want to use an industrial ('universal') vacuum hold-down system. You will also not be able to move a long PowerStick in and out with the same speed that a gantry can position itself from one end of the table to the other.

I hope that we have conveyed these limitation in our literature and commentary on the website. Buddies are great for some applications and will occasionally stand in for some big work. But the limitations need to be appreciated. (Though I confess I have Buddy envy and am hoping for one to replace a 7 year old PRT in my barn.)

Now with respect to the newer deck design, as indicated by the discussion above, there are both gains and a few losses with the new arrangement. The PowerStick system is beefed up. But as noted, we no longer provide a solid aluminum table standard with the tool. We can still provide you an aluminum table or a phenolic table. Phenolic is more machinable, stiffer, and a little lighter. A small rigid table may be the most appropriate choice for 'milling' types of applications. The beauty of the PowerStick system is that you can attach anything to it.

The one disadvantage of the new system is that the outboard edge of a table attached to the PowerStick is not held down by a v-wheel and rail, as with the earlier Buddies. Of course, such rails could always be added for really heavy work. We have felt that a useful option for the Buddy tools will be hold-down rollers that work across the table to hold down the work material. Or, they could work just at the outside edge of the table to keep the table held rigidly down agains the lower rollers -- something that might be useful with upcut spiral cutters that create an upward pull against the table.

I am attaching a photo of two Buddies about to ship here today. The first is a Buddy32 on which you can see the details of the new deck, PowerStick, and table support rollers. The second is a Buddy48 with a wood table in position on the PowerStick.

Ted Hall, ShopBot Tools

[ted]

The Buddy photos:

3600

3601

[ajf]

I finally had time last night to read through all the responses to my initial inquiry, plus read some more of the documentation on the Buddy site as well as look at various pictures of the Buddy with the new table and the old table configuration. The one item I could not find any information on is how the out feed table option now fits on to the new table configuration. The pictures on the website as well as documentation all make reference to the older table configuration. I’m still leaning towards the Buddy 48 as suitable option to my needs as long as I can also feel comfortable that I can infrequently cut larger items with the powerstick. Also I couldn’t find any pricing information regarding the Aluminum plates and Phenolic plates options that have been talked about.