Mach 3 Sewing Machine

[Hood]

There will be 2 type 25 rails mounted on each beam giving 4 in total.

Is that linear rails you are talking about? If so is accuracy of your steel frame that important? Would have thought the normal practice would just be to shim the rails at each mounting to keep them true.

Hood

[RICH]

John,
Just quickly read your postings to get a feel of what your up to.
For the frame start with a depth of section equal to 1" per linear foot of distance ( sorry you can convert ) then
check for deflection or work backwards and find the section based on total anticipated load and see what
I,S,R you need. Stiff doesn't mean resonant free. Beam Boy is fine but haven't used it in years for static loading. From a resonant point of view, nothing is better than weight as that drives the value down and you should have basic design done before you / or if someone would do analyzation. You weld up a frame, besides distortion from welding which you can kind of control ( Hood welds i think ) , after your are all done and if you machine without stress relieving it just can / may go wherever to some extent. Maybe dummy pieces on top of the frame which can be machined post attaching to frame fabrication may be a better choice. The piece is rather large so machining is not going to be cheap even for a few facing cuts.
You can analyze for motor requirements / torque required using a number of free programs. Mitsubishi, Superior Electric, Parker, and Danaher Motion all have one just to name a few.

The first step to getting a good sewing machine to have the wife hem the pants before staples, chewing gum, or crazy glue is used instead of thread.
RICH

[RICH]

Just reflecting on what Hood said, as I agree, and would be cheaper. Then epoxy the rails to the bed after
leveling / installing to tolerence you want.
By the way, cross brace the bottom, corner to corner, to keep bed from twisting.

RICH

[John Mac]

Hi Rich

I don’t think I can avoid welding and then getting the rail mounting points machined.
Attached is the solid model I am working with. It has not been optimized yet. Just a sketch to get the feel of the issues involved.

It shows ground shafting as the rail system.
I recently found a better deal with a Taiwanese rail so will use that instead.
It is a bit over a third the cost of a Bosch “Star” rail. 

http://www.hiwin.com.tw/Products.aspx?type=gw&subtype=gw_e2

Type 25 is a (Most of the time) reference to the size class of linear rail. When you check the specs most manufacturers have a system that uses the same mounting holes and overall height. The load capacity varies as does the quality and accuracy. You can not mix and match rails and runner blocks between manufacturers.
Cheers

John

[DennisCNC]

Looks like you plan on moving the machine back and forth and have the rug stationed? What about some thing like this were the rug moves and not the machine:
http://img.hisupplier.com/var/userImages/eachsun/20071128/122810.jpg

[John Mac]

Hi Dennis
Thank you for your thoughts.

The reason is floor space… These machines are big. you can save say 4x5metres = 20 square metres…. about 220 square feet by not moving the work.

The application I am working on is not quilting although the machine would be quite capable of doing it.

I did a lot of browsing with a search tool called Alibaba
http://www.alibaba.com/
Quite good for industry specific searches of the net
Attached here is a couple of machines that do not move the work:

Both made you know where.
Cheers
John Mac

[LarryL]

Hi All

An exciting time.. Over the last couple of years I have kept an eye on Mach 3 from the numerous forum posts both here, the CNCzone and on You tube. Mach 3 has become irresistible.

I work in the rag trade so for me the use of CNC will be a little different to metal working or routing. My interest is in stitching, while the overall system accuracy for stitching is a lot less than precision machining. There are other problems that must be overcome. The system I intend to create will be in the form of large Router table. With the added complication that the sewing axis will require 2 synchronized drives to drive the needle and the hook and thread bobbin separately, (The mechanism under the table of the machine) a simple 1:1 ratio but not constant speed and with a speed range of 500 – 4500 rpm, and this speed must be relative to the tool path speed. Not an easy task from my enquiries so far.  Yes it can be done mechanically but not without a lot more hardware.

My previous experience was retrofitting a CNC sewer. It took a lot of time. The hardware had to be hacked to enable user programming rather than going back to the supplier it was encrypted, or rather obfuscated. (Not uncommon for textile machinery) I also wrote a VB program to feed it with code its native code not G code. The software reads a DXF file using polylines and converts it. The math routines may come in handy again.

Today I would chuck out the hardware and start again.

I would be pleased to hear from any fellow Rag trade members, it would be fun to discuss some of the issues that relate to stitching.

Cheers

John Mac

Hi John,

My name is Larry Lamb, and I have developed a cnc quilter system using mach3 as the controlling software.   My wife uses it to make quiltes for other folks and family members, and it has been a really fun challenge.  I am using the viking megaquilter with two stepper motors to move the system, and a low voltage dc to ac relay to control the needle.  The entire system is controlled by an HP small format computer with two gb of memory and a 80 gb hdd.  also have an external drive with 500 gb of space for storage of patterns.  I am working on programming for additional control of external devices to control the takeup roller in the throat of the sewing machine, using the arduino boards to control this activity, and magnetic detection  to command movement of the Y axis carriage and the takeup roller.

If you have any questions, I would be happy to assist.

Larry

[John Mac]

Hi Larry

Thanks for your offer of assistance.

In  previous Life I bought a commercial CNC Quilter Resta H220 for my business. It was fairly old although the control system worked perfectly using a Z80 based processor. Interesting to think about that...... a few cards loaded with 7400 series IC's and the Z80 instruction code in Eprom. (Naturally I backed that up just in case). Over the 15 years we ran the machine it occasionally would develop a fault. No problem every part on the boards were easily replacable. No Surface mount stuff (Now so small it is almost dust) No multi layer boards with unfindable broken tracks. We never had to buy a replacement board.  

The minus was It used a proprietary instruction set to store programs and the instructions were obfiscated I guess they did not want to make it easy..... there was a PC based "Programming system" available for huge money or a hand programmer that was error prone. not a good option. Or you could order programs from the factory for a fee and a delay of a few weeks. the programs were delivered on "Eprom" UV erasable static ram.

I decided to make a project of it and design my own programming system via Autocad DXF into a CAM converter written in Visual basic that converted the DXF file into Resta Instruction code. It sounds easy......well it is not however after about 6 months research it was done!

And the patterns produced are dead accurate unlike the results from the hand teach mode programmer that was NQR.

I don't run the machine any more however I still have the programming system.

Cheers
John

PS:
The machine below is not the same machine but very similar, Except my machine was enlarged. We cut the main frame and made it 1200mm wider and rebuilt the rest of the machine to match it was a bit of a beast requiring 8000mm x 6000mm of floor space.    

[khalid]

The following thread needs some courage to read but having worth of information including free Gcode generator for embroidery work. Larry has also worked on the quilter and can share information on that if asked.
http://www.cnczone.com/forums/cnc_wood_router_project_log/57404-diy-_cnc_embroidery_machine.html