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What does it take to put BT40 tooling into a Fadal 4020 with cat40?

On a Fadal you cannot mix BT and CAT toolholders in the magazine because the toolchange height is different in addition to the holder clips are different. One at a time hand tool changes will work. If you are worried about the pull stud being short then leave it unscrewed a ways, install the holder then check if it is tight. If not screw the stud in farther and try again. Shim if necessary.

Ed.
 
I have to agree with EG. There are lots of Pinzbohr and BIG Kaiser style boring heads on Aliexpress, and I'd take those over a shitty old Criterion any day - and I say that as a D'Andrea/Kaiser/Sandvik …

Criterion suck, sure. We all have at least one and we all hate them.

The point is Aliexpress is going to be a crapshoot as far as what will actually show up in the box. Could be serviceable, could be scrap metal. Can’t go by “reviews” as they’re bought and sold like anything else.

I agree for the price of pull studs do not experiment with making your own.
 
The point is Aliexpress is going to be a crapshoot as far as what will actually show up in the box. Could be serviceable, could be scrap metal. Can’t go by “reviews” as they’re bought and sold like anything else.
I don't like aliexpress. It's a pita to find anything, there's no organization, and if you search "light switches" you'll get not only light switches but bathtubs, lawn furniture, and tire sealers.

But it's no different than fleabay, craigslist, or a first order from any catalog store like Penn Tool or J&L. You do what checking you can then take a leap of faith. If it goes well you buy from the same place again. if it's crap you chalk it up to experience and move on. This is how it's been since i was in sixth grade and sent away for the little sea horses. That didn't work out too well but I'm not still crying about how buying things from Indiana is a total crapshoot.
 
My VF-1 has BT-40, this may or may not be relevant. The tool holder in the carousel is different and the tool zero height may be different also, so replacing one tool holder may cause it to crash when changing tools.
 
Since when is Criterion a good boring head?
It's overall a dinosaur of a tool but, can get the job done in some cases. Since he didn't specify a bore diameter or tolerance, finding a nice one with a micro adjusting head was kind of tough.

I'd still rather get by with a boring head that isn't going to smash the tool changer if someone forgets and accidentally commands a tool change.

I also don't doubt there are super precision shops in China that make beautiful tooling. I have some of it. I'm not sure Aliexpress is the place to find it though.
 
I'm not sure Aliexpress is the place to find it though.
I really dislike alibaba ... but at one time the only place in the US to buy what people call "multifix" toolposts/holders was enco. They were also the only ones selling the narex boring and facing heads. And I bought a west german quick-change system with a 9 B&S taper shank for the gorton that was top notch and no one else had them or even heard of them. No one else had anything for 9 b&s.

Enco sold mostly shit but ....

Sometimes you gotta put on the bigboy pants and do the research yourself. Not everything grows on kumbaya trees watered by diverse gardeners who will hold your hand and gently guide you to the best product at the best price.
 
Criterion is like the Atlas lathe of boring heads.
🤣 Dude, if you think you're going to get an argument here, you're going to have to try harder. I wouldn't hand load a BT-40 head in my machine, regardless of brand. Heck, I won't install most "used" holders of any kind because I don't want the spindle bore damaged. There are nice boring heads on eBay for less than a grand. A smashed carousel isn't worth it.
 
There are some things that it's ok to cheap out on, pull studs are not one of those things.
Yep, but those who think that way are the same ones that want to bore SB chevy blocks and face the heads on an ol worn out BP :willy_nilly:
When his stud breaks and the crap hits the fan and metal is blown all over inside his Fadal........he'll realize then:D
 
Ok so it's not too bad to do... I guess I will science it out and make some pull studs. Sounds like it will definitely be worth is too me to save thousands on the tooling.

When it breaks, and it will, it'll at a minimum destroy the spindle taper, maybe to a point you can't exchange for a rebuilt spindle.
 
On a Fadal you cannot mix BT and CAT toolholders in the magazine because the toolchange height is different in addition to the holder clips are different. One at a time hand tool changes will work. If you are worried about the pull stud being short then leave it unscrewed a ways, install the holder then check if it is tight. If not screw the stud in farther and try again. Shim if necessary.

Ed.

That's a recipe for disaster.

Very small changes in pull stud position compared to the taper make very large differences in pull stud tension. Especially if he has a locking drawbar.

You could loosen the pull stud less then maybe 1/8-1/4 turn and have no pull stud tension whatsever. Or at least just enough to make it feel you have enough.
 
BT Tooling is the norm in Australia, and over the years, I've converted quite a few used machines brought in from the US, that were configured for CT, to BT.

The length of the taper, from the Gauge Line to the end of the taper that accepts the pull stud is circa 4mm shorter for the BT tool. With all the machines I've converted, no change of the draw bar or its position was required. The position of the retention knob of the pull stud, relative to the gauge line of the Tool Holder, was exactly the same when comparing the assembled BT and CT Tool Holder, with the difference in the Tool Holder Taper length being made up in the respective Pull Stud for each type of Tool Holder, Usually the thickness of the flange that interfaces the end of the tool holder was thicker by the difference in the taper length for the BT Tool Holder..

From a machine tool manufacturing perspective, it makes sense, as except for the drive dog detail, the spindles for either BT or CT spec machines are the same. Accordingly, for a given machine, a BT spec machine could have a CT Tool Holder with the correct CT Pull Stud for the machine, hand loaded without issue. Vice versa applies for a CT spec machine.

Regards,

Bill
 
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If you are worried about the pull stud being short then leave it unscrewed a ways, install the holder then check if it is tight. If not screw the stud in farther and try again.
That's got to be amongst the dumbest and potentially dangerous advice I've seen publish in quite a while and totally unnecessary if the correct Pull Stub for the particular machine for the Tool Holder style is used.
 
That's got to be amongst the dumbest and potentially dangerous advice I've seen publish in quite a while and totally unnecessary if the correct Pull Stub for the particular machine for the Tool Holder style is used.

Some Fadals have a locking drawbar. It has to be shimmed to get the correct tension. remembering back there was a significant difference in drawbar tension between hand tight and a correctly torqued pull stud.
 
That's got to be amongst the dumbest and potentially dangerous advice I've seen publish in quite a while and totally unnecessary if the correct Pull Stub for the particular machine for the Tool Holder style is used.
If you think any pull stud mfr. is making pull studs that differ based on machine, point them out. I think the situation in reality is that there are two standards. Most machines have enough adjustment that you can adapt the machine to either standard, but If you want to run a mix of BT and CAT tool holders on your machine, you will need to shim the BT pull studs to make the mix be compatible. And that may only be possible on some machines. For others, pick a standard and stick to it.
 
If you think any pull stud mfr. is making pull studs that differ based on machine, point them out. I think the situation in reality is that there are two standards. Most machines have enough adjustment that you can adapt the machine to either standard, but If you want to run a mix of BT and CAT tool holders on your machine, you will need to shim the BT pull studs to make the mix be compatible. And that may only be possible on some machines. For others, pick a standard and stick to it.
There are more types of pullstuds than I can count, and you absolutely have to match them to your machine.

Most common pullstud patterns are available in different BT/SK lengths IME, so shimming pullstuds is not something you should have to do unless you have something very oddball.
 
If you think any pull stud mfr. is making pull studs that differ based on machine, point them out.
As Gregor states it and your Maritool link confirms that.


Only one length is offered for every pull stud... And they don't offer any pull studs for BT40. So while I agree that you must use pull studs that fit your machine, you may need to do some shimming if you are running a mix of CAT40 and BT40 tool holders.
Of course only one length would be offered for every type of particular pull stud. Machine Spindles and Tool Holder are made to close tolerances, and therefore, if the pull studs are made to reasonably close tolerances, there would be no need to be shimming the pull studs. In the majority of cases, quality Pull Studs have their spigot journal, underside surface of the flange and the retention knob detail ground after heat treatment; accordingly, there is no reason why close tolerances can't be maintained.

According to the Maritool Link you provided, Maritool does offer pull studs for BT40 Tool Holders.

remembering back there was a significant difference in drawbar tension between hand tight and a correctly torqued pull stud.
The relative length difference from the retention knob and the gauge line of the tool holder, between the flange making interment contact with the end face of the Tool Holder, hand tight and correctly torqued is infinitesimal and therefore, the difference in drawbar tension is miniscule. Far more length difference occurs through the false brinelling of the grip surface of the retention knob after relatively short service.
 
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