Straight Edges

[PaulH]

I currently use a basic steel rule as my "straight edge" but having recently acquired one of David Charlesworth's books I realised that when he talked about ignoring any straight edge that doesn't specify a tolerance, probably means my steel rule isn't "straight" after all!

David recommends a Starret 2 ft, nickel-plated engineers straight edge No 386. I found one of these here and was shocked at the price!

What do others use?

Is it really necessary to spend that much? (i.e. does it make a noticeable difference?)

Thanks,
Paul.

 

[gardenshed]

here[/url] and was shocked at the price!

Thanks,
Paul.

That's a good price for a Starrett 386, you'll be hard pushed to find a better one.

 

[MikeW]

My personal experience is--and without having any DC books at this time--is that it matters more with machine set up than woodworking per se.

Lee Valley makes some with fine enough tolerances.

LV straight edges

Take care, Mike

 

[Anonymous]

Personally i think its just another way of getting you to part with your money!

 

[Paul Chapman]

I have several steel rules and none of them is straight, which is quite frustrating. I recently bought one of the Veritas aluminium straight edges which seems quite well made, you can stand it on a surface without having to hold it, and the price wasn't too bad, so I'm quite pleased with it.

Cheers :wink:

Paul

 

[Alf]

Oooo, we are suffering from a terrible outbreak of engineering-itus on this forum at the moment. ](*,) Like Paul, I have a Veritas aluminium one and IMO it's more than accurate enough for dealing with a material that will move anyway...

Cheers, Alf

 

[dedee]

I don't need an accurate straight edge for machine tool set up so
chesterman 1' and 2' steel rules are good enough for me.

Andy

 

[Anonymous]

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[Shivers]

buying every gizmo out there that norm or any other so called'authority' says totally defeats the point of trying to be a craftsman,making your own ancillary tools is good enough, i once had a 6ft straight edge made of 12mm perpex (straightened over a carbide bladed surfacer),i also have a giant 5ft T square made from mahogany with a 1/4" corian blade made in the same way,spending money on accurate to 1/10,000 of an inch tools is a waste ---think of all those workshop jig books you could get with that money,the most sentimentally valuable tools i own are the ones i made & have been with me for yrs.

regards


shivers

 

[Paul Chapman]

What do you need a straight edge for exactly?

For me it's about cumulative errors and the problems these cause when putting a piece together. For example, I have had to make lots of stuff over the years from man-made boards. I used to use off-cuts of Contiboard, Contiplas or MDF to guide my router or circular saw and I had lots of problems with things not being straight. I now use large, square sub-bases on my routers and circular saw and Trend clamp guides which are straight.

This is just one example, but I find it can be very useful and save a lot of time and aggravation to have a straight edge to check that things are in fact straight. But it all depends on what you are doing. If you are making a rustic chair from green timber then it's probably not that important but if you are making a cabinet from man-made boards then, in my view, straightness of components becomes very important.

Cheers :wink:

Paul

 

[Anonymous]

You must enter a message when posting.

 

[promhandicam]

I currently use a basic steel rule as my "straight edge" but having recently acquired one of David Charlesworth's books I realised that when he talked about ignoring any straight edge that doesn't specify a tolerance, probably means my steel rule isn't "straight" after all!

I guess it depends a lot on what you are trying to measure and why - and also (trying not to be facetious) how good your eyesight is. I would have thought that for the vast majority of uses a good basic steel rule would be perfectly adequate - particularly if it is used primarily as a straight edge and not as a scraper - not that I'd ever do anything like that :^o

I tend to use a 3' spirit level if I need a long straight edge, the edge of a 8' x 4' sheet if I need a very long straight edge and if I need a very very long straight edge a piece of string or a chalk line. For shorter straight edges - the rule from my combination square or a little 6" steel rule (if I can find where I put it). Even if you have the ability to measure to within 0.0001" or 0.002mm so what! If it is necessary to get to those sorts of tolerances, then making something with wood is probably not the correct choice of material.

Steve

 

[Anonymous]

Hey, I may be wrong, but surely woodworking requires far less fine tolerences than precision engineering.

If we're talking about variences of tenths of a millimetre in the straightness of a piece of wood - well that's crazy! Movement of the wood will have rendered your measurements useless by the morning!

IMHO, a bog standard steel rule is more than accurate enough for woodworking.

In fact piece of MDF or ply checked by sighting along the edge is good enough!

Brad

 

[Paul Chapman]

What do you need a straight edge for exactly?

snip..
if you are making a cabinet from man-made boards then, in my view, straightness of components becomes very important.

Cheers :wink:

Paul

I find squareness more of a prob - but resolved usually by measuring, or matching pieces side by side etc. Straightness is easy - you just plane the edge of a board and look down it. In woodwork, if it looks straight then it is straight.

chers
Jacob

We'll have to agree to differ If you make a cabinet (and I'm talking here about man-made boards where fine tuning with a plane isn't always an option) and then fit a door to it and either the door or the frame isn't straight (even though it looked straight to the eye), then it can look awful.

Cheers :wink:

Paul

 

[ike]

OK, just being the devils advocate here - nothing personal :wink: .

Did 19th century makers of fine cabinet work need an engineering grade straightedge, square or other precision widget?. Maybe they might have bought them had they existed. But they didn't and still did fine cabinet work. So why now?

cheers,

Ike

 

[Shivers]

I'd like to think i get straight edges from a well set up table saw/panel saw,& i'd also like to think my surfacer is well set up for giving a good edge,a £100+ straight edge is overkill.


regards shivers.

 

[Paul Chapman]

Some of us don't have the luxury of saw benches, planers, thicknessers and the like And besides, my Veritas straight edge cost only £17-50 which I reckon is pretty good value

Cheers :wink:

Paul

 

[Shivers]

Some of us don't have the luxury of saw benches, planers, thicknessers and the like And besides, my Veritas straight edge cost only £17-50 which I reckon is pretty good value

Cheers :wink:

Paul

I see your point there,i guess i was thinking more along the lines of a very large straight edge--which i would make myself,& if i already had done that ,-whats the point in buying one.


regards

shivers.

 

[woodbloke]

I agree with many of the comments thus far. I think that an engineering degree of straightness isn't needed for most woodworking jobs....I use a pair of Maun steel straight edges (600mm and 1m) with a tolerance guaranteed to 0.01% of their length...forget what I paid for them but they weren't too expensive, though I don't use them as a guide when using a knife

Paul - I did think about aluminium straight edges but thought the edge too 'knickable' when using it with something like a Stanley knife.

There is a time tho' when you need an ablsolute straight edge and that is in cutting veneers to make a book matched joint. Using a blade with a single edge bevel it's possible (if you're lucky) to cut a joint in a pair of veneers so that they fit straight from the knife - any discrepancy here in the straightness of the edge will of course be magnified by the joint. FWIW in trade we used the edge of a piece of 18mm mdf as a guide and a broken oddment of ground machine hacksaw blade as a knife - Rob

 

[Paul Chapman]

Paul - I did think about aluminium straight edges but thought the edge too 'knickable' when using it with something like a Stanley knife.

I agree entirely - aluminium would be no good for use with a knife. I have a very old steel straight edge, which at some point had been made into a T-square, which I use for cutting.

Cheers :wink:

Paul