|Robin Graham||25/06/2017 23:40:35|
|548 forum posts|
I bought a combination square a while ago, pretty much an impulse purchase. It's a carp piece of kit, can't remember the brand, but under a tenner. It's turned out to be useful, but would be more so if it were actually square and 45 degrees as advertised - it's quite badly out, and quite sticky on the slide. I don't think I can justify £150+ for a Mitutoyo, Starret or whatever.
ARC have one at about 40 quid - has anyone experience of that model? Or can suggest another at that sort of price? I'm not looking for super-precision, a couple of thouish per inch would be more than good enough, but maybe even that's unrealistic for this type of tool at this (or any!) price point?
3651 forum posts
Couple of thou per inch might be asking a lot of what is basically a carpenter's tool. With the moveable blade held in position by a thumbscrew etc it is inherently unstable. If you want that kind of accuracy a proper engineer's try square would suit better. And a precision engineer's protractor or angle gauge to do the 45.
I've found the most cost effective combination sets are to be had buying secondhand older but good brand name sets. I don't use them for anything more accurate than marking out angle iron to be cut with an angle grinder etc. though.
|Neil Wyatt||26/06/2017 17:33:33|
16098 forum posts
They seem to improve in quality once you get the far side of £30. The very cheap ones are mazak and indeed carp.
|Clive Foster||26/06/2017 19:47:14|
|1749 forum posts|
A good brand machinists combination square will have been made to better than 10 thou per foot accuracy. Brand new old line Starrett, M&W, B&S square and protractor sets made to maybe ± 2 thou per foot nominal. Time was a good combination square was an expensive piece of kit and had to be made well to persuade a craftsman to buy it. Not so much now.
Big box and import? How wide is your pencil line? If it came from B&Q an ordinary framing square will be better.
|Robin Graham||27/06/2017 23:25:17|
|548 forum posts|
Thanks for your replies. I've had a nagging interest in combination squares since I bought the cheapo one, but hadn't come across any mid-range ones until I happened to to come across the ARC offering. It seemed to be either cheap tat, or proper (ie Mitutoyo etc) stuff at £150+. I have engineers squares and other precision doo-dahs for when it really matters,but was looking for something rough and ready (but not quite so rough as the ones I have, which are about 2mm out over the 300mm bar!).
Mazac eh - no wonder the screw binds!
I've been reading the 'crap V-block' thread. It made me think that we (or I at least) expect too much for too little these days...
Edited By Robin Graham on 27/06/2017 23:26:21
|David Paterson 4||28/06/2017 00:21:08|
|83 forum posts|
Are they not the 'shifting spanner' of measuring tools?
Good stable ones are good for finding centeres, repeatable (unmeasured) angles, and depth of big holes.
They are very useful carpentry tools
|Martin King 2||28/06/2017 07:01:58|
|593 forum posts|
I have just listed a nice 12" Starrett that came in this weeks haul!
|John Haine||28/06/2017 09:58:07|
|2543 forum posts|
S/H ones of good make on eBay tend to be more expensive than buying new, I found when I went through this loop. I ended getting a nice M&W one from Allendale in a fitted box. It seems dead accurate for things like setting up on the mill etc. Tends to be brought out on special occasions.
|Martin W||28/06/2017 11:50:52|
|789 forum posts|
I think it is worth pointing out that, and I quote 'the ARC offering' has the heads made of cast iron and not Mazac which puts them into another class. All too often products can be damned by casual association and while no one has said the the ARC units are Mazac it, like the V Blocks thread, places problem products in association with reputable suppliers.
Usual disclaimers re any involvement with ARC.
Edited By Martin W on 28/06/2017 11:52:10
|Mike Poole||28/06/2017 13:16:20|
1967 forum posts
The combination set is what I believe made Starrett a reputable name in tools, they claim to have invented it and made them accurate enough for the serious metalworker. I must admit I do use one for woodwork where it is a most useful tool. I tend to think any tool that is adjustable cannot be used as a reference without checking that it is true first. As the sole user of my tools I know when a square has been dropped and check it but a combination square could always pick up a bit of dirt, swarf or a burr which could throw it out slightly which may matter depending on what you are doing.
|David Cambridge||28/06/2017 22:16:09|
|252 forum posts|
For what it’s worth, I bought a cheap combination square from Amazon, or ebay, or something like that. The ruler was made out of a banana, and the head was made of some sort of chocolate. It was about half the cost of Arc.
In fact I’ve done that a few times. i.e. bought cheap from Amazon, wasted my money, and then gone to Ketan! One day I’ll learn my lesson and just go to Ketan straight away (No relation – just a happy customer!)
Edited By David Cambridge on 28/06/2017 22:17:26
|Robin Graham||28/06/2017 22:18:58|
|548 forum posts|
Thanks for further comments.
Martin W - in my original post I said that I was looking at the ARC offering at around £40 because I didn't get on with my 'under a tenner' jobs. Neil replied that the very cheap ones (which would presumably include the ones I have) had Mazak heads,and said that quality improved above the £30 price point.I can't understand how this exchange could be construed as a slur on the quality of the ARC product and I assumed that my further comment 'Mazack eh, no wonder the screw binds' would be taken in the context of the thread (ho-ho!) , ie referring to the cheapo ones I had.
John Haine - thanks for the pointer to Allendale. I had a look and they are doing a a basic M&W for £15 - they claim squareness 0.2mm in 300mm, so better than a thou per inch. Got to be worth a punt at that price!
|Eric Arthrell||28/06/2017 22:40:36|
|47 forum posts|
I always used M&W when plating and fabricating,
Check for square butt up to plate scribe a line flip it over scribe a second should lie directly on top of first . I would check mine when starting to mark anything out .
Sorry if I am teaching you to suck eggs
|Robin Graham||28/06/2017 22:43:15|
|548 forum posts|
Thanks David. It's good to hear an opinion from someone who actually has the tool. I think that's all I needed to know actually!
|Robin Graham||28/06/2017 22:45:45|
|548 forum posts|
Yes Eric, I have sucked that particular egg, but thanks anyway!
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