Is There A Market For A Good, Cheap BP CNC Conversion?

[HimyKabibble]

I've done what I think is a very nice "4-axis" CNC conversion on my Taiwanese BP clone - X, Y, knee and quill. It's good for 350IPM in X/Y, 50 IPM on the knee, and 250 IPM on the quill, all DC servo-driven, all ballscrews (except the knee, which retains the stock leadscrew, and is used primarily for tool length compensation). Having been out of work for the last 18 months, I'm looking for money-making opportunities to help pay the mortgage. One of the things I'm considering is making pretty much bolt-on conversion kits, starting with the quill drive, which seems to be the most difficult for most people.

Is there a market for a *good* quill drive for, perhaps $1200?
Is there a market for a *good* 3-axis kit for perhaps $3000?

Each kit would include all necessary hardware (brackets, bearings, zero-backlash ballscrews, servo motor, pulleys, belts, all required bolts, nuts, etc.), and be, to the extent possible, completely bolt-on, with very few, if any, modifications to the machine.

Regards,
Ray L.

[TOTALLYRC]

Hi Ray,

I would say there is a market for such an item. I for one would have looked real hard if it was available. I would think that there are a lot of manual machines just waiting for a bolt on kit to make them CNC.

For those of us who want to make some money with our machines instead of making a project of our machines, I think it would be a great option.

In my opinion, if you have a machine in good condition and can bolt on the parts and have a fully functional CNC mill for $3K it would be worth while. Especially important for people who have the machine setup in their basements.

The biggest drawback when contemplating my j-head Bridgeport was the cost of the ball screws. Good screws would have cost more than the CNC machine I purchased.

At this point, since the resale value of a used Bridgeport has dropped so much, I am reconsidering converting the old gal so I could have a second machine. Let me know if you need some dimensions. Mine is a 9"x 42" machine. You will probably need to find someone with a 9" x 36" to get some dimensions from.

One other item to consider is that series one machines have an 18" X axis travel where my 9x42 has like 24-25.


Mike

[Quentinlong]

For $3000 I would seriously look at the bolt on kit, as opposed to making my own. How about some videos of your BP in action or some photos?

[HimyKabibble]

Originally Posted by TOTALLYRC Hi Ray, I would say there is a market for such an item. I for one would have looked real hard if it was available. I would think that there are a lot of manual machines just waiting for a bolt on kit to make them CNC. For those of us who want to make some money with our machines instead of making a project of our machines, I think it would be a great option. In my opinion, if you have a machine in good condition and can bolt on the parts and have a fully functional CNC mill for $3K it would be worth while. Especially important for people who have the machine setup in their basements. The biggest drawback when contemplating my j-head Bridgeport was the cost of the ball screws. Good screws would have cost more than the CNC machine I purchased. At this point, since the resale value of a used Bridgeport has dropped so much, I am reconsidering converting the old gal so I could have a second machine. Let me know if you need some dimensions. Mine is a 9"x 42" machine. You will probably need to find someone with a 9" x 36" to get some dimensions from. One other item to consider is that series one machines have an 18" X axis travel where my 9x42 has like 24-25. Mike

Mike,

When it comes to ballscrews, there's good, and then there's good enough. You're right, very high precision ground screws are crazy expensive. But, for hobby use, they're also not necessary. Few applications really *require* that kind of accuracy. I would use high quality rolled screws, which are very nearly as good, and a whole lot cheaper. The ones I used on my BP clone are the Nook XPR screws, which are 0.001"/foot max lead error, and very nearly as smooth and quiet as a ground screw. Even ground screws are typically only good for 0.0005"/foot. The rest is done with screw mapping on the big machines. Even so, the Nooks I bought were over $500 for the screws and nuts.

Regards,
Ray L.

[HimyKabibble]

Originally Posted by Quentinlong For $3000 I would seriously look at the bolt on kit, as opposed to making my own. How about some videos of your BP in action or some photos?

That is something I've been meaning to do for some time. I just keep forgetting when I'm setup and running something that would look good on video!

Below are a few pictures of the machine, as it was right after I put the X/Y/knee drives on.

Regards,
Ray L.

[TOTALLYRC]

Originally Posted by HimyKabibble Mike, When it comes to ballscrews, there's good, and then there's good enough. You're right, very high precision ground screws are crazy expensive. But, for hobby use, they're also not necessary. Few applications really *require* that kind of accuracy. I would use high quality rolled screws, which are very nearly as good, and a whole lot cheaper. The ones I used on my BP clone are the Nook XPR screws, which are 0.001"/foot max lead error, and very nearly as smooth and quiet as a ground screw. Even ground screws are typically only good for 0.0005"/foot. The rest is done with screw mapping on the big machines. Even so, the Nooks I bought were over $500 for the screws and nuts. Regards, Ray L.

Hi Ray,
Under $600 would have been great but at the time I was looking the set of bolt in screws was over $1K.
I agree on the nook xpr being a great value but 2 years ago I didn't know about them.

Mike

[nate]

There must be a market for these products. I for one would be interested in a Z Drive.