|49 forum posts|
All my slitting saws have horrid runout - 'ching ching ching'.
I've bought (reasonably) cheap one and really good ones. They're all marginally sloppy on the (good quality) arbor.
I've read comprehensively on this across the web, and it appears that this is the norm! Seen the various threads here too.
Having said all this, they seem to cut absolutely fine: the only compromise seems to be running slight faster (ca. 300 rpm for a 2.5" saw) than ideal to avoid it 'snatching'. Whole thing was cool to touch after a 15mm cut in mild steel, and taking 0.5mm cut per pass.
Just wondered if anyone had found a source of slitting saws that were cut true?
423 forum posts
some are worse than others. I've never had a true running one.
I just run mine faster so the chingy bit comes round more often. and just hope that bit will wear away so the rest of it gets a look in.
|Peter Hall||23/10/2011 20:34:27|
|114 forum posts|
Welcome to the club. All mine were horrible too, but were very substantially better when I switched from (cheap) milling chuck to (even cheaper) ER collet chuck to hold the arbor. I'm using the tiny Sieg X1 mill and I bought my collets and collet chuck direct from CTC tools in Hong Kong. Worth a look if you are on a tight budget.
|Tony Pratt 1||23/10/2011 20:56:08|
|1820 forum posts|
I would hazard a guess that any old stock 'Made in England' cutters you can get hold of will run true.
1120 forum posts
Hi everyone is correct, I've been cutting metal for over 50 years and its always been the same but some are better than others.
|147 forum posts|
When I was an apprentice we used to have this problem. Given that you have sufficient diameter on the saw a good 'cure' is to fit cheek plates as you do on grinding wheels.
|263 forum posts|
I use 'English' slitting saws and I can truly say, they are the same from new.
The only ones that don't do it are the small solid carbide ones I have, but I think they may be ground by a different method as they are a lot more expensive.
You might find that ones with fewer teeth have less runout, purely because the grinding wheel doesn't wear out of true as much as when it is grinding a larger number of teeth. I suspect they only true the wheel up after doing the whole circumference of teeth, that is what I do when resharpening mine, so the first ones ground will be shorter than the last ones because the wheel has lost a bit of it's 'meat' by the time it gets to the last tooth.
It doesn't really matter anyway, it you need to slit to a certain depth, just take your start point from when the first tooth starts to touch.
|Clive Hartland||23/10/2011 22:27:38|
2756 forum posts
Surely centricity is a function of the center hole of the saw. Coupled with any error from the arbor and morse tapers or other mounts .
In production and when sharpened before sale they pick up eccentricity.
Are they checked at all?
I have had saws that were eccentric from new, expensive saws, but I have also had others that were fine.
Perhaps the saws should be sharpened on the arbor they run in.
Thicker saws do not give as much trouble but take more power to cut with and then chatter.
|DAVID POWELL 4||29/10/2011 15:46:09|
|26 forum posts|
Anyone any idea how fast a slitting saw should run. Searched all the books but nothing. Not even the people selling them know. Only help was from an ole timer at the Midlands show who said 'run em slow'
|Tony Pratt 1||29/10/2011 16:19:30|
|1820 forum posts|
It depends on you saw diameter, but 50 rpm would be a good starting point for the 3"-4" sizes ones. There is a theroetical speed for all cutters depending on cutter material and diameter plus material to be machined.
|Martin W||29/10/2011 19:01:19|
|908 forum posts|
Try looking at this link Slitting Saws on page 13 of the pdf document there are details of cutting speeds for hss slitting saws, diameter v material etc. Should be right as this company supplies/manufactures the items.
|1218 forum posts|
Have looked at the American site, Martindale.com and on page 9, they show piccie of support washers, hardened, precision ground. Bottom of page 13 they say that in absence of a drive key, the support washers do the driving. The washers are similar to those used for grinding wheels, but I suggest that no -one tries to use these on grinding wheels - they are not identical. Hope above explains how the makers intend use of their products.
|Chris Trice||30/10/2011 01:40:22|
1371 forum posts
Since slitting saws are usually made from HSS, I use the same rpm as if a HSS lathe tool was cutting the same material at the same diameter as the slitting saw. In other words, if you're cutting mild steel with a 3" slitting saw, use the same speed as cutting 3" diameter piece of mild steel in the lathe with a HSS tool. Lots of cutting fluid helps too.
|DAVID POWELL 4||30/10/2011 09:27:12|
|26 forum posts|
Thanks everyone who responded to my query on running speeds of slitting saws. Now I know after about 2 years of searching. Using this site it took less than 24 hours.. Thanks again
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