TorontoBuilder
Ultra Member
So I have just found out about a person, Nicholas Bull, who developed his own micro linear encoders and a DRO controller that pairs with an ordinary android tablet or phone that has the TouchDRO app installed on it.
Nick's target market is the European micro lathe market, such as the Schaublin 102, but the size of the encoder hears make them ideal for anyone wanting to use magnetic tape embedded on the underside of the cross slide.
What I find most interesting / exciting about Nick's system are the micro magnetic read heads, and that he designed his controller to use the existing TouchDRO app so users can see reduced cost to install encoders on multiple machines.
According to Nick, size was the driving factor in the development of his DRO system and he went through a few iterations of encoder heads before arriving at the current design. Nick's encoder head is based on a 14x8 mm pcb, with an OSRAM AS5311 High-Resolution Magnetic Linear Encoder. The pcb has 4mm radiused corners, and can sit in a slot/pocket cut with an 8mm end mill. The connector is tangential with one end of the slot and is 5mm in diameter. The encoders are a/b quadratic incremental and run on 3.3v, and they've been designed to read 1mm pole pitch magnetic tape.
In contrast to the 14x8 mm pcb encoder the traditional chinese magnetic encoder head is a whopping 34x24 mm. The wire on the chinese encoder protrudes straight outwards requiring even more space, while the microDRO head can use an angled plug that points 90 degrees downward.
A custom CPU was required to translates the pitch / pulses received by the quadratic encoder from the magnetic tape and converts them into an absolute position to be sent to the TouchDRO software. The controller sends new data with every move of the encoder head.
Imagine this tiny pcb mounted to read a magnetic strip on the underside of the cross slide. The pcb would project less than 20 mm from the back of the cross slide, and in my case I'd 3D print a mount and encapsulate the pcb in resin to bond it to the mount. The only issue I see for my lathe is that I already ordered heads and tape with a different pitch.
so many mounting options are possible with this pcb.
So do I order this for my swiss mill, or put the other chinese magnetic scales on my mill and use this microDRO for my Chipmaster lathe? Either way I plan to order a 3 axis kit to check this out.
Nick says a set for a 2 axis Schaublin 102 lathe with complete read heads with brass brackets, cpu with cables and magnetic tape is going to be under £300. Without the brass brackets it will be under £250. He states that the CPU with wires is the expensive bit, at £100, while each read head pcb is £35. He could cut the price further if you want to source wires and connectors locally.
Nicholas is UK based, so shipping and conversions will apply. I'd be interested in organizing group buy if there is interest from others.
Nick's target market is the European micro lathe market, such as the Schaublin 102, but the size of the encoder hears make them ideal for anyone wanting to use magnetic tape embedded on the underside of the cross slide.
What I find most interesting / exciting about Nick's system are the micro magnetic read heads, and that he designed his controller to use the existing TouchDRO app so users can see reduced cost to install encoders on multiple machines.
According to Nick, size was the driving factor in the development of his DRO system and he went through a few iterations of encoder heads before arriving at the current design. Nick's encoder head is based on a 14x8 mm pcb, with an OSRAM AS5311 High-Resolution Magnetic Linear Encoder. The pcb has 4mm radiused corners, and can sit in a slot/pocket cut with an 8mm end mill. The connector is tangential with one end of the slot and is 5mm in diameter. The encoders are a/b quadratic incremental and run on 3.3v, and they've been designed to read 1mm pole pitch magnetic tape.
In contrast to the 14x8 mm pcb encoder the traditional chinese magnetic encoder head is a whopping 34x24 mm. The wire on the chinese encoder protrudes straight outwards requiring even more space, while the microDRO head can use an angled plug that points 90 degrees downward.
A custom CPU was required to translates the pitch / pulses received by the quadratic encoder from the magnetic tape and converts them into an absolute position to be sent to the TouchDRO software. The controller sends new data with every move of the encoder head.
Imagine this tiny pcb mounted to read a magnetic strip on the underside of the cross slide. The pcb would project less than 20 mm from the back of the cross slide, and in my case I'd 3D print a mount and encapsulate the pcb in resin to bond it to the mount. The only issue I see for my lathe is that I already ordered heads and tape with a different pitch.
so many mounting options are possible with this pcb.
So do I order this for my swiss mill, or put the other chinese magnetic scales on my mill and use this microDRO for my Chipmaster lathe? Either way I plan to order a 3 axis kit to check this out.
Nick says a set for a 2 axis Schaublin 102 lathe with complete read heads with brass brackets, cpu with cables and magnetic tape is going to be under £300. Without the brass brackets it will be under £250. He states that the CPU with wires is the expensive bit, at £100, while each read head pcb is £35. He could cut the price further if you want to source wires and connectors locally.
Nicholas is UK based, so shipping and conversions will apply. I'd be interested in organizing group buy if there is interest from others.
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