milling material on eBAY

Are they worth the price - anyone with experiences ?

Are they made of steel strong enough ?

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What kind of steel is used compared to the standards "8.8", "12.9" or maybe even harder ?

RDGtools will NOT answer this question so I fear the clamping kit is made of "black butter".

Best regards KS, Denmark

Reply to
KS
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They are the usual Chinese sets. Don't have one (just AMF, sorry ), but have read reports that they are OK and no complaints. Maybe you get a better price somewhere else (like at rc-machines).

Nick

Reply to
Nick Mueller

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I suspect RDG couldn't answer your question as I doubt they would know the specific steel standard used in manufacture. These sets appear to be made to a generic pattern in a variety of places. The one I bought

15 years ago from Axminster tools has been fine and a larger one I bought 18 months ago from J&L Industrial is equally good. I suppose it depends on what you are trying to clamp but I have not heard personally of too many problems with these sets in the home workshop. Even in my previous professional career we made our own clamping sets, or at least the apprentices did, from normal mild steel; they lasted for years and rarely gave trouble.

Neither of my sets is particularly hard so I suspect they are nothing special by way of the steel used. I'm not sure they need to be really as normal mild steel is quite capable of cracking out cast iron T slots on small machines. Obviously your need may be more demanding and if so I think I would go to an industrial supplier and be prepared to bay a LOT more. Sorry I can't comment on the specific RDG set as I haven't bought from them.

Regards

Keith

Reply to
jontom_1uk

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Sorry, forgot to add that we purposely stayed with mild steel because as long as the T nut was properly fitting the bolt would usually strip before the table casting fractured. Essential when you have lots of machines and lots of first year apprentices.

Keith

Reply to
jontom_1uk

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They will work fine for their intended purpose.

You do not really think you need more clamping power than that for something that takes a 7/16 inch size tee slot, do you?

This is a bog standard, generic hold down kit, and as such, they do not come with certificates or promises other than that they will work as advertised. Espescially as they are priced in the low end of the range.

If you bend or break a tool as these, you are trying too hard!

If I am not too far off, the standards you refer to are for High strength metric bolts. Not even close to these parts.

Cheers Trevor Jones

Reply to
Trevor Jones

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I can't comment on the particular kit for sale but what I can tell you is you don't need high tensile bolts for clamping down milling jobs. You're never going to put enough force into a cutting tool to move something that's bolted down reasonably tight. I just use ordinary mild steel 1/2" Whitworth studding for clamping on my Bridgeport clone and cut bits off to whatever length I need. I've never needed to tighten anything hard enough to get anywhere near stripping the threads. In fact if your time is your own you could make a clamping kit easily enough for free from scrap bits of mild steel. My mill came with a reasonable selection of T nuts, coupling nuts etc but I once had to clamp a job where the only way was for the studding to go through 7mm holes so I made a couple of special T nuts to take 1/4" Whit studding. Mild steel was perfectly good enough to do the job. On that basis any commercial clamping kit will be fine whatever it's made from. It therefore boils down to whether you'd rather pay 30 quid for a something ready made and nicely blacked so it won't go rusty or spend a few hours milling up your own set.

Mild steel might only have half the tensile strength of something like a

10.9 or 12.9 bolt but it'll still apply several tons of clamping force. 3/8" MS studding, which is what a 7/16" slot would probably use, has an area of 0.11 sq inches and at 30 tons tensile that comes to 3.3 tons at the limit. You'd get 2 tons clamping force out of that without going mad on the spanner. 1/2" studding would be almost double the strength.

Anyway as others have said you'll probably break the slots on the bed before you break the clamping kit.

Reply to
Dave Baker

I have had a set for about 8 years after spending a life time at work with MS rods and standard nut and thin washers, Finished work and did just the same and then at one show went mad and spent money on a set. Best days work I ever did. I would not be without mine. Just use them as they should be no pipe on the spanner. In a rack just waiting to help you get the job done. What I did do was cut some 1/4" X 1" flat bar into 1" long bits and drill a hole in the make a good washers. I use them on the Lathe, miller shaper & the drill. Not sure which stall I got them from but they are all the same in that price range.

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Reply to
Bill

They're fine...used one for years. What's the problem? --

Chris Edwards (in deepest Dorset) "....there *must* be an easier way!"

Reply to
Chris Edwards

"KS" schreef in bericht news:469375cd$0$2464$ snipped-for-privacy@dread12.news.tele.dk...

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Using an identical set for years now without any problems. Pity not all my machines have the same slot size ;-) Dirk

Reply to
PG1D/PA-11Ø12

Nothing?

Nick

Reply to
Nick Mueller

"Chris Edwards" skrev i en meddelelse news: snipped-for-privacy@4ax.com...

As I wrote in the original posting - I fear they are made of "black butter"

But I have ordered now - so I trust you !

Best regards KS, Denmark

Reply to
KS

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