Hey all,
I'm trying to setup for some 2-sided machining on some guitar bodies. Am I right in assuming that a 2 dowel-pin setup down the center X axis of the part should suffice as long as the pins are exactly aligned with the machines X-axis. Then all that would be required is a simple part flip in the y axis?
Example parts with registration holes drilled:
Am I on the right track here?
Thanks,
Fred
Fixturing question
- highpockets
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Re: Fixturing question
Fred,
That's exactly how I do all the plaques I cut.
I built a jig that gets screwed to my main table in preset bolt holes. The jig has temporary material alignment pins. The first toolpath I run is "Registration Holes". I put the pins in the material, machine side A then flip and machine side B. When I don't need the jig I can remove it for other projects.
On the jig I have written the XY Absolute machine coordinates of the center point of my jig when mounted on the table. That way i just enter the XY Absolute machine coordinates in the control software, move to that location and set my XY zero.
That's exactly how I do all the plaques I cut.
I built a jig that gets screwed to my main table in preset bolt holes. The jig has temporary material alignment pins. The first toolpath I run is "Registration Holes". I put the pins in the material, machine side A then flip and machine side B. When I don't need the jig I can remove it for other projects.
On the jig I have written the XY Absolute machine coordinates of the center point of my jig when mounted on the table. That way i just enter the XY Absolute machine coordinates in the control software, move to that location and set my XY zero.
John
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Re: Fixturing question
Thanks John,
Kinda what I figured.
I think whats going to be nice too, is I can drill the registration holes to best favor the wood grain and not having to worry about squared up sides or perfect 90 degree corners... What do you use for your pins? Wood or metal?
Cheers,
Fred
Kinda what I figured.
I think whats going to be nice too, is I can drill the registration holes to best favor the wood grain and not having to worry about squared up sides or perfect 90 degree corners... What do you use for your pins? Wood or metal?
Cheers,
Fred
- highpockets
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Re: Fixturing question
I have had mixed success with using wood dowels as registration pins. There weakness is the tolerance of the dowel, the limited length of engagement in my spoilboard and the fact that my spoilboard is MDF which is too soft to resist the dowel deflecting under load.
I would recommend more than two dowel locations spread as far apart as possible, and a large diameter to spread the load into the spoilboard. Use calipers to measure the actual dowel diameter and adjust the hole size accordingly. Lastly I glue in the dowels to the spoilboard for production runs then trim the off after and deck the board flush.
I would recommend more than two dowel locations spread as far apart as possible, and a large diameter to spread the load into the spoilboard. Use calipers to measure the actual dowel diameter and adjust the hole size accordingly. Lastly I glue in the dowels to the spoilboard for production runs then trim the off after and deck the board flush.
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Re: Fixturing question
Fred,
Trust me, it will work. I paid for two ShopBots doing it that way. PM me if you want more on the process.
Bill
Trust me, it will work. I paid for two ShopBots doing it that way. PM me if you want more on the process.
Bill
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Re: Fixturing question
On the jig I have written the XY Absolute machine coordinates of the center point of my jig when mounted on the table. That way i just enter the XY Absolute machine coordinates in the control software, move to that location and set my XY zero.
John. you use mach3 don't you ? If you do then why don't you just set up a work co-ordinate for your x & y Values ? I have 2 or 3 of them saved for repeat work I do using jigs that are always located in the same position on the machine table So simple to home the machine & then select G56, G57 or what ever work off set it is. I have the z set at zero ( top of it's travel) for all my work offsets though as I use different thickness materials with some of the jigs
John. you use mach3 don't you ? If you do then why don't you just set up a work co-ordinate for your x & y Values ? I have 2 or 3 of them saved for repeat work I do using jigs that are always located in the same position on the machine table So simple to home the machine & then select G56, G57 or what ever work off set it is. I have the z set at zero ( top of it's travel) for all my work offsets though as I use different thickness materials with some of the jigs
- highpockets
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Re: Fixturing question
I do Martin, but not everyone has Mach3 (and I'm not sure what other controllers do) so talking about the G5x presets I figured would just complicate what should be a simple answer.martin54 wrote:On the jig I have written the XY Absolute machine coordinates of the center point of my jig when mounted on the table. That way i just enter the XY Absolute machine coordinates in the control software, move to that location and set my XY zero.
John. you use mach3 don't you ? If you do then why don't you just set up a work co-ordinate for your x & y Values ? I have 2 or 3 of them saved for repeat work I do using jigs that are always located in the same position on the machine table So simple to home the machine & then select G56, G57 or what ever work off set it is. I have the z set at zero ( top of it's travel) for all my work offsets though as I use different thickness materials with some of the jigs
I have the G5x number on the jig as well as the XY absolute machine coordinates (just in case).
John
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Re: Fixturing question
Very nice jigs. I tried a SG and had some minor registration problems, but I think it was a missed toolpath recalculation...Bill_L wrote:Fred,
Trust me, it will work. I paid for two ShopBots doing it that way. PM me if you want more on the process.
Bill
More investigation and experiments are needed.
Thanks!
Fred