Heath's Woodworking Projects

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JPG
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Post by JPG »

shipwright wrote:Not sure if that was a compliment or an insult, not that I mind. Everyone is entitled to thier opinion. Both "builders" and "craftsmen" come in good and bad, the difference is in the product, not in the method of achieving it.
IMOH

Paul M
I consider your comments to be that of a CRAFTSMAN and most definitely meant as a positive compliment. As you said Craftsmen build things, builders assemble them!

I also agree with the context of the last statement above! I just think a craftsman is more admirable, and accomplishes things independent of any 'original' plan of someone elses imagination.!
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
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shipwright
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Post by shipwright »

Thanks JPG. I was hoping that's what you meant.

Paul M
Paul M ........ The early bird gets the worm but the second mouse gets the cheese
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mickyd
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Accuracy of cuts and measurment accuracy

Post by mickyd »

My 2 cents re accuracy of wood cuts and the associated measuring device you need to use to verify 'process output'. I'll try real hard not to get on the soapbox or get too winded but... measurement accuracy and tolerances are just two areas that my entire career has been based on. I'll just stick to the facts. There won't even be anything arguable here. (got that jpg?):D Only argument would be if I make a math error.

I learned first hand when working this lantern project that some of the dimensions are robust / later fixable and others are CRITICAL TO FUNCTION as cut.

Manufacturing drawings have + / - tolerances associated with each part feature that if maintained, should result in an functional part. Woodworking drawing plans that I have seen do not give you a + / - tolerance to follow which leaves every cuts tolerance and associated measuring technique to the woodworkers discretion. When building a project that has a potential of tolerance stack up of several features, you need to understand each feature as they relate to each other to know whether or not you cut accurately enough.

Here's the case with the candle lantern design. The plan called out for glass cut 3-9/16" wide by 1/8 nominal thickness. Nowhere on the plan does it say to wait and cut the glass based on your finished lantern opening. Joe Rookie (mickyd) goes out and has the glass cut precisely to size. Frank Experienced (charlese) tells micky later that you NEVER cut the glass until you've completed the woodworking which is absolutely 100% excellent advise that will now stay with me forever. I build my first prototype lantern doing the best I could and the glass doesn't fit. Did I mess up my cuts? Yes but....did I know I messed up to the point of making a non-functional assembly as I was making it? No, not until I went to put the glass in. I had no tolerances to go by, no +/- on the critical dimensions. Had I not cut the glass, I would have had no problem as long as I made all lanterns the same. Just cut width to fit.

Some wood projects have critical dimensions and you can't wait til your done to cut those. It's a progressive process where you have to complete one step before going to the next. The width of the base is a good example. Unless you do all the math, you do not know what the width tolerance of the base should be. Too wide and sides won't assemble with the 45° miters flush resulting in an extra operation to narrow the width. Too narrow and it will fall out and you either have to remake or change the design to get it to function.

The above is why I now will have a tendency to make sure cuts are close to exact, pulling out the .001" caliper vs. the 1/32 steel scale UNLESS I understand and have figured out whether a dimension is critical or not. For example, I can tell just by looking at the plans for the lanterns that the height of the stiles is not critical (unless I've cut my glass to height already). A wooden ruler with 1/16" grads is 100% acceptable. However, the cuts that result in the inside width are critical. (you want to put yourself through some mental gymnastics, figure the nominal inside width from the plan). If you hit all the dimensions exactly, you have an inside width of 3.750" vs. a glass width of 3.713" (3-9/16" cut width + .150" actual glass thickness due to the way it is positioned inside (see the pdf for glass positioning) Total clearance bewteen the glass and the inside of the lantern???.....only ~ 1/32" :eek: . Divide this clearance by the number of cuts and that leaves you less than .010" error per cut. Y'ain't gonna measure those dimensions with a 1/16" or even a 1/32" graduated scale!!

So point is....you have to know your design inside and out to know how closely to cut and measure. If you don't / can't / won't figure it out, be as accurate as you can and you won't kick yourself.
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Post by heathicus »

See, I would have thought it was better to cut the glass first. Then you could make the lanterns to fit the glass. But maybe that's just because I'm more comfortable working with wood and have never cut glass before? If you're off and the glass is 1/32 too wide, how easy is it to trim that much off of the glass? I've no clue. But I could sand the inside of the lantern sides until the glass fits.

The plan does say, "Buy glass before you make the lanterns so you can size the base rabbet. ...(H)ave your glass dealer cut four 3-9/16" wide pieces each to 3-3/4", 4-3/4", and 5-3/4" long." Buy your glass first and have your glass dealer cut to these sizes equals "cut the glass first" by my interpretation.

The process I would take is, cut the glass first, cut the stiles and rails to accommodate the glass, tape everything together and test fit before gluing, and make any adjustments to the wood as necessary either cutting length down or sanding to make the inside "bigger."

But I trust the experience of others here who say to cut the glass after all of the woodworking. So I have to ask... why? Obviously I'm overlooking something with my approach. What is it that I'm overlooking?
Heath
Central Louisiana
-10ER - SN 13927, Born 1949, Acquired October 2008, Restored November, 2008
-10ER - SN 35630, Born 1950, Acquired April 2009, Restored May 2009, A34 Jigsaw
-Mark V - SN 212052, Born 1986, Acquired Sept 2009, Restored March 2010, Bandsaw
-10ER - SN 39722, Born 1950, Acquired March 2011, awaiting restoration
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Post by dusty »

So maybe there is good reason to own calipers, dial gauges, expensive steel rules, quality squares and good marking tools.

You might want to add a good pair of spectacles to that list as well. All the precision tools in the store won't do you any good if you can't see those itty bitty 1/64" marks.
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Post by mickyd »

heathicus wrote:See, I would have thought it was better to cut the glass first. Then you could make the lanterns to fit the glass. But maybe that's just because I'm more comfortable working with wood and have never cut glass before? If you're off and the glass is 1/32 too wide, how easy is it to trim that much off of the glass? I've no clue. But I could sand the inside of the lantern sides until the glass fits.
Ain't easy to remove small amounts of glass without the the 'right' equipment. I'm not a glass expert by any means but I know that I have been unsuccessful at removing 1/32" with a belt sander, disk sander, grinding wheel.
heathicus wrote:
The plan does say, "Buy glass before you make the lanterns so you can size the base rabbet. ...(H)ave your glass dealer cut four 3-9/16" wide pieces each to 3-3/4", 4-3/4", and 5-3/4" long." Buy your glass first and have your glass dealer cut to these sizes equals "cut the glass first" by my interpretation.
Your interpreting this correctly. The problem I see with this approach now is if your glass doesn't fit due to woodworking errors, it is possible that neither your glass or your project can be 'fixed'. Say for example you accidentally made your stiles 1/2" too tall and didn't realize it until you were ready to install your glass. Your glass would in turn be too short. You couldn't repair your wood because you'd have to remove most of your top rail.
heathicus wrote:
The process I would take is, cut the glass first, cut the stiles and rails to accommodate the glass, tape everything together and test fit before gluing, and make any adjustments to the wood as necessary either cutting length down or sanding to make the inside "bigger."
In this case, you are right but again if your error left you with insufficient wood, trouble.
heathicus wrote:
But I trust the experience of others here who say to cut the glass after all of the woodworking. So I have to ask... why? Obviously I'm overlooking something with my approach. What is it that I'm overlooking?
see above :D
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Post by heathicus »

On a very small project like this, if you're off by 1/2", you're WAY off and you are in trouble. I was thinking more along the lines of being off 1/8" or less.
Heath
Central Louisiana
-10ER - SN 13927, Born 1949, Acquired October 2008, Restored November, 2008
-10ER - SN 35630, Born 1950, Acquired April 2009, Restored May 2009, A34 Jigsaw
-Mark V - SN 212052, Born 1986, Acquired Sept 2009, Restored March 2010, Bandsaw
-10ER - SN 39722, Born 1950, Acquired March 2011, awaiting restoration
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Post by shipwright »

Mickyd, Mickyd,Mickyd... Why would you want the glass to be an exact fit anyway? Admittedly I haven't looked at the plans but as I understand it (and I know you'll correct me if I'm wrong) the glass is in a rabbet and you don't get to see the edges of it, no? I would fit the wood to the glass planning anywhere from 1/8 to 3/16 play room for the glass. I would also have the glass cut that much undersize if I had already finished the woodwork. They are different materials and have different properties. On a bigger project tightly fitted glass could be broken by expanding wood or in a small one the joints could be opened up by the same action in the wood.

As for the critical dimensions, stop looking at the plans and look at the pieces. Dont measure one piece and then measure and mark the other. Put one piece against the mating piece and mark where the cut goes. That way you don't even need a ruler and accuracy is all about how sharp your pencil is. Capisce?

Bottom line is really relax and enjoy and if it dosen't work you learn something. You're doing great but you're working way too hard at it.

Good luck

Paul M
Paul M ........ The early bird gets the worm but the second mouse gets the cheese
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Post by charlese »

This is fun! Let me throw in another possible variable - - Let's think of a larger project, something like the latest X style lights on Mark's (mbcabinetmaker) latest project. On his project the glass filled the entire space between rails and stiles.

Question - How much smaller should the glass be than the entire space inside the rails and stiles? Will the glass fit loosely and rattle? Will it fit tightly and likely break, or crack with wood movement or door racking? What type of spacers to use around the glass, if any?

Glass first - or wood first? Although it is true that a woodworker can always fit a project around known sizes of glass, this woodworker must work around specific measurements. That kind of woodworking has never thrilled. nor been easy for me. I find it much more enjoyable to work the wood toward measurements, not exactly on them (like 0.001").

Do the woodwork first then take the piece to the glass shop and out will come glass sized just for your project! This also works for me!

Chisels, scrapers, planes and sanding do wonders to fit pieces together. Sawing "close enough" works for me! Trying to make the wood exactly fit exacting specifications is frustrating, not fun, at least for me. When working from plans, my measurements always seem to change (from the plans) as the project proceeds. Don't know about others, but this woodworker has NEVER been able to duplicate measurements of a plan. Sometimes the plan comes from my paper or computer. I gave up trying long ago and my fun increased while my projects improved.
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Post by JPG »

charlese wrote:This is fun! Let me throw in another possible variable - - Let's think of a larger project, something like the latest X style lights on Mark's (mbcabinetmaker) latest project. On his project the glass filled the entire space between rails and stiles.

Question - How much smaller should the glass be than the entire space inside the rails and stiles? Will the glass fit loosely and rattle? Will it fit tightly and likely break, or crack with wood movement or door racking? What type of spacers to use around the glass, if any?

Glass first - or wood first? Although it is true that a woodworker can always fit a project around known sizes of glass, this woodworker must work around specific measurements. That kind of woodworking has never thrilled. nor been easy for me. I find it much more enjoyable to work the wood toward measurements, not exactly on them (like 0.001").

Do the woodwork first then take the piece to the glass shop and out will come glass sized just for your project! This also works for me!

Chisels, scrapers, planes and sanding do wonders to fit pieces together. Sawing "close enough" works for me! Trying to make the wood exactly fit exacting specifications is frustrating, not fun, at least for me. When working from plans, my measurements always seem to change (from the plans) as the project proceeds. Don't know about others, but this woodworker has NEVER been able to duplicate measurements of a plan. Sometimes the plan comes from my paper or computer. I gave up trying long ago and my fun increased while my projects improved.
If I understand the 'x doors' correctly, the glass is wider/taller than the 'x' openings(overall) and a single glass attached on the back side with mirror mounts. NO rabbets!
╔═══╗
╟JPG ╢
╚═══╝

Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
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