Woodpecker ThinRip Guide

[festal]

its either jigs or drugs lol

[member=75283]4nthony[/member] i bet you if you squeeze the calipers hard enough you will get 4mm on the dot

 

[Bob D.]

its either jigs or drugs lol

[member=75283]4nthony[/member] i bet you if you squeeze the calipers hard enough you will get 4mm on the dot

But how do you get repeatable squeeze pressure? Need another instrument.

 

[4nthony]

[member=75283]4nthony[/member] i bet you if you squeeze the calipers hard enough you will get 4mm on the dot

I can only evacuate so much blood from my finger tips before they go numb [poke]

 

[smorgasbord]

Consistency likely matters more than the absolute error.  I am sure that I will have more repeatability with the thin rip jig (or the cheap alternative that many of us use) than having to use a DRO and moving the fence each time.

The Woodpecker's Thin Rip Guide, and similar designs, requires that you move the fence each time.

 

[Bob D.]

Consistency likely matters more than the absolute error.  I am sure that I will have more repeatability with the thin rip jig (or the cheap alternative that many of us use) than having to use a DRO and moving the fence each time.

The Woodpecker's Thin Rip Guide, and similar designs, requires that you move the fence each time.

But the fixed distance for your thin rip is on the opposite side of the blade. The fence is not in the equation other than an edge parallel to the blade by which to guide the work.

The critical dimension that does not change it the distance from the rip guide to the outboard (with respect to the fence) side of the blade.

 

[ChuckM]

Snip.
The critical dimension that does not change it the distance from the rip guide to the outboard (with respect to the fence) side of the blade.

That's only part of the critical dimension. The other part is the distance between the offside edge of the workpiece and the fence, which might be different each time the fence is moved and reset as one taps the fence for fine adjustments. The fence is definitely in the equation.

 

[smorgasbord]

OK, did a quick set of 3 thin rips using just my tablesaw with DRO and a Starrett caliper.
I have previously measured my blade's kerf as 3.22mm.
So to get 4mm thick pieces, I need to set my fence to 7.22mm. The Wixey only reads to .1mm, so 7.2mm.

I ripped 3 pieces and labeled them A, B, C. The results:
A - 3.985mm
B - 4.03mm
C - 3.985mm

[attachimg=1]

The procedure was:
1) Rip the piece to just take off the slightest bit. This sets the fence zero point for the next cut.
2) Zero the Wixey Incremental read-out (push a button).
3) Move the fence until the DRO reads 7.2mm
4) Rip a piece
5) Goto #2 and repeat

Now, there is some tap-tap-tap to get the fence to 7.2mm, but there is no "feel" involved. And yes, as someone upthread reported, I could move the fence the tiniest amount and not have the readout change. And certainly the Wixey is not a true precision instrument, but given not just wood movement but my ability to run slightly different sized pieces over the blade against the fence with the same pressure, etc. I'm super happy with a standard deviation variance of 0.004725mm

But, most importantly, I spent $150 just once and get to use the DRO for any tablesaw cut involving the rip fence. No need to buy a additional $200 flip-stop system for the tablesaw to make repeated cuts. No need to have fancy rigs with positioners for cutting tenons (like this shopbuilt one
from Stumpy Nubs), just something that rides on the tablesaw fence, where the measurements will all be done on the DRO.

 

[smorgasbord]

Minor update: I emailed Wixey earlier today about their accuracy claims, as reported above:

Accuracy:
Decimal = +/- .002 in. per foot
Fraction = +/- 1/500 in. per foot
Metric = +/- .13 mm

The response from Barry (just hours later) is:

This is the first time someone has asked this in 15 years, which is hard to believe. I personally put these specs back together in 2006 and have no idea where that number came from. You are right. It should be 0.051mm/ft or 0.17mm/meter. We have not updated that page since it was first created.

 

[Birdhunter]

I needed to make a few strips at 6mm to fit into a Domino 6mm mortise. Using the Thin Rip, the first try resulted in 6.3". Ooched the guide in and the second try was 6.0mm.

Fun to use a very high quality tool. I know I could have gotten the same results using my old method, but this way was more fun and a lot faster.

 

[ChuckM]

Snip.
Fun to use a very high quality tool. I know I could have gotten the same results using my old method, but this way was more fun and a lot faster.

This is no different from using a premium chisel to complete a cut that can equally be done with a plastic handled chisel from a big box store. Toys are toys, and we don't always need to justify them based on rational thinking or grounds.