LumberJocks

Bowling Alley Workbench #12: All is not lost... or is it? HELP!!!!!!!

  • Advertise with us
Blog entry by PurpLev posted 1808 days ago 3412 reads 0 times favorited 21 comments Add to Favorites Watch
« Part 11: A Cap for the Gentlemen, a Skirt for the Dames Part 12 of Bowling Alley Workbench series Part 13: The Top #3: Putting it Together with an Inverted Dovetail »

I was working on fitting the skirt to the front of the bench, and it looks fantastic. in order to get to the final dimensions of 30” width of the top, I’m missing 1/8” extra material between the benchtop and the skirt to fill in the gap, while keeping the skirt flush with the legs fronts. so far so good.

while fitting the skirt to the legs, I noticed that the gap on the left side of the bench is larger than the right side… a quick reach to the tape measure confirmed that indeed the main-slab I was using (with nails in it) wasn’t square – to be honest, I didn’t even think about checking for it in the first place which I should have.

so now I have a top that is based on a non square part, which makes the entire top not square:

as you can see in the picture, there is a smaller gap between the top and the skirt on the right size (~1/8”) then on the left size (~5/16).

my original thought was to create a narrow strip to fill this gap, and make that strip tapered – problem is , this is a really narrow strip, and the taper is so fine, that it’s a 99.9% likely that I won’t be able to get that taper right – wasting time and energy for nothing.

second thought, and this is the method I’m going to be using here, is to place a straight edge across the length of the front of the top, square it with the end, and route the front of the top clean – this will take the taper off, and leave me with an even ~5/16” (I’ll probably enlarge it a bit to maybe 3/8” gap which will be easier for me to fill in (thicker strip). then I just need a square strip to fill in the gap, and I’m done with it.

the thing that somewhat concerns me is the fact that the dog hole strip is aligned and parallel with the skewed main slab – making the dog hole strip not parallel to the front of the bench. the angle is minimal, but for holding longer pieces – the dogs will have an offset of ~3/16” (? about…) which might not hold parts properly for planing…. AAARRRRRRGGGGGG…...

I really hope this will not be a pronounced problem, or this top will need to be burned…

Any ideas/suggestions/confirmation is MOST welcome… this is really bugging me.

-- ㊍ When in doubt - There is no doubt - Go the safer route.



21 comments so far

View Craftsman on the lake's profile

Craftsman on the lake

2353 posts in 2023 days


#1 posted 1808 days ago

I know this mightto sound like a bad idea besides just living with the small variation.

Let everything be determined by the dog hole strip. Think of it as the starting point. Plane/cut some off the dog hole strip side to make that side of the bench parallel with it. And, if you want to plane the other side to also make it parallel. The joint lines of your top won’t be perfectly parallel with the edges but that might not show unless you were looking for it. Of course at that point your bench might not be perfectly square but the ends definitely wouldn’t show it.

-- The smell of wood, coffee in the cup, the wife let's me do my thing, the lake is peaceful.

View Jon3's profile

Jon3

493 posts in 2690 days


#2 posted 1808 days ago

This to me is one of the downside of the schwarzian method. I prefer to build my entire top, entire base, then mate them cleanly. Less chance of this kind of error, imo.

View PurpLev's profile

PurpLev

8475 posts in 2233 days


#3 posted 1808 days ago

Thanks guys, the more I think about it the less I’m worried about it, measuring the angle offset gives me 0.1 degree , which when planing boards, I probably won’t notice… lol. the dog hole strip although not parallel to the front of the bench IS inline with the vise jaw… so there is no problem there… more esthetics I guess, and once I fill this up, its not even something that will be visible. – hell , even now it’s not visible, which is why I haven’t noticed it to this point.

I guess I had to put it out in the open to clear my mind of it, and get a better chance to rethink this over.

Danial – thanks, but the top is already mortised to the legs, and end cap already installed – changing the angle on the dog hole is practically impossible unless I cut it completely off. but that option did cross my mind…. uuggghhh…

bentlyj – I thought about that too, but setting up the piece to hold the strip of 80” might be tricky unless I construct some sort of 80”+ sled for the planer for this, which I don’t wish to do at the moment, I think I’m going to square out the front of the top, and use a square filler strip.

Jon – what is the shwarzian method? I thought Chris’s method is to build the top from scratch, like you did yours?

-- ㊍ When in doubt - There is no doubt - Go the safer route.

View Craftsman on the lake's profile

Craftsman on the lake

2353 posts in 2023 days


#4 posted 1808 days ago

Jon3.. I couldn’t help but wiki he schwarzian method.

http://en.wikipedia.org/wiki/Schwarzian_derivative

Purplev…. you should read this page to help you avoid this problem again.

;-)

-- The smell of wood, coffee in the cup, the wife let's me do my thing, the lake is peaceful.

View jlsmith5963's profile

jlsmith5963

297 posts in 1933 days


#5 posted 1808 days ago

shwarzian method?... hmmm better google that one, oh yes here it is.

Rational solutions for Schwarzian integrable hierarchies

Rational solutions? In woodworking?... somehow I don’t think we are in Kansas anymore…

-- criticism: the art of analyzing and evaluating the quality of an artistic work...

View jlsmith5963's profile

jlsmith5963

297 posts in 1933 days


#6 posted 1808 days ago

damn beaten to the punch by 4 minutes…lol

-- criticism: the art of analyzing and evaluating the quality of an artistic work...

View jlsmith5963's profile

jlsmith5963

297 posts in 1933 days


#7 posted 1808 days ago

although i do like my text link better (if i say so myself)...lol

-- criticism: the art of analyzing and evaluating the quality of an artistic work...

View PurpLev's profile

PurpLev

8475 posts in 2233 days


#8 posted 1808 days ago

gotcha – thanks for the links guys.

to be honest – and I think I mentioned it before. if I had the choice ($$$ as well) I would opt to build the top from scratch myself as well, but sometimes we do what we do with what we’ve got – thats what makes us different than a manufacturing machine – we’re able to reshape, and reform things creatively. that… and Jon3 post a while back suggesting to post “errors” and “problems” and how we deal with them – is where this post comes from.

-- ㊍ When in doubt - There is no doubt - Go the safer route.

View Craftsman on the lake's profile

Craftsman on the lake

2353 posts in 2023 days


#9 posted 1808 days ago

You’re right jlsmith. Your webpage has a better explanation. It’s much clearer. But, it just may be that you’re not following the math as well as I.

2+2=5 but only for very large values of 2.

-- The smell of wood, coffee in the cup, the wife let's me do my thing, the lake is peaceful.

View Craftsman on the lake's profile

Craftsman on the lake

2353 posts in 2023 days


#10 posted 1808 days ago

So true Purp….

The sign of a true craftsman: he has the skills to hide his mistakes.

-- The smell of wood, coffee in the cup, the wife let's me do my thing, the lake is peaceful.

View jlsmith5963's profile

jlsmith5963

297 posts in 1933 days


#11 posted 1808 days ago

Mistakes? Mistakes? There are NO mistakes in woodworking!!!!

-- criticism: the art of analyzing and evaluating the quality of an artistic work...

View jlsmith5963's profile

jlsmith5963

297 posts in 1933 days


#12 posted 1808 days ago

putting on my monk’s robe

To attempt perfection is an insult to God. (or something like that)

-- criticism: the art of analyzing and evaluating the quality of an artistic work...

View PurpLev's profile

PurpLev

8475 posts in 2233 days


#13 posted 1808 days ago

True – jlsmith, it is said that persians make mistakes on purpose when they make rugs, since people used to claim that they rugs are perfect, and the persians believe that only god can be perfect…

-- ㊍ When in doubt - There is no doubt - Go the safer route.

View sIKE's profile

sIKE

1271 posts in 2339 days


#14 posted 1808 days ago

Sharon,

Since you are using round dogs I would not be too concerned, if you were using square dogs though you might have to make some minor changes to thier faces.

-- //FC - Round Rock, TX - "Experience is what you get just after you need it"

View PurpLev's profile

PurpLev

8475 posts in 2233 days


#15 posted 1808 days ago

sIKE, although not as severe as square dogs -but even round holes when misaligned with the jaw create shear force on the part being clamped – and might twist the part out of the dogs if enough force is applied (by planing, or pounding a chisel in). but as I stated in a comment, in an afterthought – the dog hole strip and the vise jaw Are inline – just not parallel to the back/front of the table… and the angle is small enough that even that shouldn’t be a major issue.

-- ㊍ When in doubt - There is no doubt - Go the safer route.

showing 1 through 15 of 21 comments

Have your say...

You must be signed in to post the comments.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com

Latest Projects | Latest Blog Entries | Latest Forum Topics

GardenTenders.com :: gardening showcase