Parf Guide mark 2 issues and questions

[Ampman117]

So it’s got to be the jig I assume? Does anyone elses jig have the smallest amount of play when the locater dogs are in the jig when drilling out the 20mm holes?

I started drilling my top today. I haven't got all my 20mm holes drilled yet, but I did try placing the jig using the locator dogs in a few spots - no play in my jig when I did that.

I'm going to do the remaining 20mm holes that require locator dogs tomorrow or possibly after Christmas. If I get any play in the jig over the course of the remaining holes I will let you know.

 

[Ampman117]

Any ideas on how to approach this best?

I'm totally new to this, so take this with a grain of salt...but if you have jigs or other things that are sized for 3/4 holes maybe you could use the 20mm anchor dogs to attach your jigs to the 20mm top?

If you don't have jigs or other equipment that really needs the 3/4 holes, buying into the 20mm system could be less of a headache...

 

[HowardH]

I needed to make a MFT top but I used my Shaper Origin instead.  It was pretty easy to create a grid of 20mm holes on a 96mm spacing using the snap to grid function.  It turned out well enough for my needs.

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[rmwarren]

[member=396]HowardH[/member] curious how the accuracy is over that large a tape field? Are you planning to use the top with tall dogs/guide rails for cutting?

I made an aluminum fence with Origin to use with a Parf guide-made MFT and found that the holes were off just enough to mess up alignment when I got further out from 0/0 point on the grid. The error was only around a couple 100ths of an inch but it was enough to mess up my use.

RMW

 

[HowardH]

[member=396]HowardH[/member] curious how the accuracy is over that large a tape field? Are you planning to use the top with tall dogs/guide rails for cutting?

I made an aluminum fence with Origin to use with a Parf guide-made MFT and found that the holes were off just enough to mess up alignment when I got further out from 0/0 point on the grid. The error was only around a couple 100ths of an inch but it was enough to mess up my use.

RMW

I'm going to use it as an assembly table. I have a complete Dash-board system coming my way soon to use as a cutting station.  I will say it is very accurate. The only way for it not be accurate is if I screwed up the .svg file I made to make it. That's the beauty of it. I scanned the entire tape field as a workspace and place the file on that.  It doesn't know or care if I am drilling one hole or 200. 

 

[rmwarren]

[member=396]HowardH[/member] curious how the accuracy is over that large a tape field? Are you planning to use the top with tall dogs/guide rails for cutting?

I made an aluminum fence with Origin to use with a Parf guide-made MFT and found that the holes were off just enough to mess up alignment when I got further out from 0/0 point on the grid. The error was only around a couple 100ths of an inch but it was enough to mess up my use.

RMW

I'm going to use it as an assembly table. I have a complete Dash-board system coming my way soon to use as a cutting station.  I will say it is very accurate. The only way for it not be accurate is if I screwed up the .svg file I made to make it. That's the beauty of it. I scanned the entire tape field as a workspace and place the file on that.  It doesn't know or care if I am drilling one hole or 200.

As I understand it there is a cumulative reduction in tolerance the further you get from 0/0 on the grid. Shaper I believe publishes the spec, I don't recall the specifics but over a large MFT it's probably enough to mess up a cut with dogs for alignment.

For assembly it's not an issue.

RMW

 

[HowardH]

I never knew that but I'm not sure how that's possible when each position is mapped out precisely at 96mm intervals.  I believe what you are saying but I need to ask the Shaper folks about that. 

 

[rmwarren]

I never knew that but I'm not sure how that's possible when each position is mapped out precisely at 96mm intervals.  I believe what you are saying but I need to ask the Shaper folks about that.

If you are on their forum there are a couple threads with specifics. IIRC it's basically a limit in the accuracy of the camera over a distance.

Some folks have posted about techniques to minimize it, but one thread referred to an offset of 1.5mm over 800.

For most woodworking it's really not an issue, an MFT used for a cutting station is an outlier.

RMW

 

[HowardH]

I reached out to Shaper Support and they directed me to this link from the Shaper forum. This excerpt is from their CEO:

"With Origin, the best way to think about accuracy is in terms of a percentage of target. Origin is currently capable of achieving ~99.7% or 99.8% overall accuracy. For small projects (e.g. ~6 inches or under), expected accuracy of cuts performed by a reasonably experienced user may be measured in single-digit thousandths of an inch. For medium-size projects (e.g ~1 to 3 feet), expected accuracy of cuts may be measured in hundredths of an inch. For larger size projects (e.g. ~4 to 8 feet), expected accuracy may be measured in tenths of an inch."

Seems to me that a .002" over 8' is pretty good. (.2"/96")

 

[rmwarren]

I reached out to Shaper Support and they directed me to this link from the Shaper forum. This excerpt is from their CEO:

"With Origin, the best way to think about accuracy is in terms of a percentage of target. Origin is currently capable of achieving ~99.7% or 99.8% overall accuracy. For small projects (e.g. ~6 inches or under), expected accuracy of cuts performed by a reasonably experienced user may be measured in single-digit thousandths of an inch. For medium-size projects (e.g ~1 to 3 feet), expected accuracy of cuts may be measured in hundredths of an inch. For larger size projects (e.g. ~4 to 8 feet), expected accuracy may be measured in tenths of an inch."

Seems to me that a .002" over 8' is pretty good. (.2"/96")

And I don't disagree this is awesome given the conditions. It would likely impart error for the cutting station use of an MFT, no issue for clamping. I wasn't trying make any other point.

My own use to make the AL fence was within a couple hundredths over a 288mm length, with 0/0 at the mid point. Dogs slipped right thru into the underlying MFT holes.

I'd first tried to do it with 0/0 at one end and by the time I got to the far end the few hundredths had added up and I'd would have needed to hammer the last dog in. Still an awesome level of accuracy, just not enough for the use I was aiming for.

You may get better results.

RMW

 

[HowardH]

I wish I was that precise!