What's new
What's new

BT30 pullstuds

crossthread82

Hot Rolled
Joined
Apr 1, 2022
Location
Maryland
Hey all I have what some are probably going to say is a stupid question but I'm going to ask anyway so flame away lol.

I'm looking at two different brands of bt30 machines (Brother and DMG) and plan on getting both, one uses the 60 degree studs and the other uses the 45 degree studs. I know in a perfect world you'd use the correct studs in each machine however with us being a job shop/prototype shop holders get swapped around a lot and I know one of our guys is bound to mix them up. And quite honestly I don't want to have to try and keep these same but different holders separated.

I've heard of people running 45 degree studs in machines that call for 60 degree with no issues but not sure how good of an idea that is? Experience doing this? Opinions?

Is it possible to switch the gripper in one of the machines so they both use the same studs?
 
We should get some good info from 2outof3 and BrotherFrank, and maybe Frank at Maritool, but my un-informed knee-jerk opinion is that it's a terrible idea. The speed and violence of a Speedio tool change and that fact that the pull stud is already the weak point makes me not like that idea at all. But thats just speculation.
 
I never even knew they had different angles on them.

I have seen different lengths of pull studs, that don't work between different machines.

@LOTT What, you don't like when the tool changer throws the tool and holder against the inside of the machine and makes you sh*t your pants? 😁
 
I'm guilty of this when I'm to lazy to switch pull studs.Never any production but light stuff they interchange and work. Never dropped any tools.I have no speedio just a old 1992 brother and a new TongTia VTX-5.
 
You send the Brother holders out to a shop that will PVD coat them Speedio Blue, so you never mix them between machines:


(From a shop with an older fleet of Robodrills and a new fleet of Speedios, to prevent pull-stud confusion. You can also just have the pull-stud coated, but the results are not as dramatic as can be seen in the picture)
 
I am pretty sure Brother Frank has said it is ok, but not my call. I do like that blue, where did you get that done? Oh, and $$?
 
I am pretty sure Brother Frank has said it is ok, but not my call. I do like that blue, where did you get that done? Oh, and $$?
I would not use the 45 degree pull studs on a new Speedio. OP, If you want to only get one style pull stud, go with the 60 degree. The other machine will likely be out of there long before the Brother... ;)
 
I would not use the 45 degree pull studs on a new Speedio. OP, If you want to only get one style pull stud, go with the 60 degree. The other machine will likely be out of there long before the Brother... ;)
I figured so lol.

On a serious note is it possible to switch the grippers in the drawbar so they could use a common pullstud?
 
I am pretty sure Brother Frank has said it is ok, but not my call. I do like that blue, where did you get that done? Oh, and $$?

It wasn't done locally - the PVD supplier is back east and mostly deals in quite large volumes. This was a run of about 200 holders and they just tacked it onto a production run batch and had the color changed.
 
The pull-stud is the life's-blood of a bt-30 spindle. I feel this is kind of a crazy question. (crazy as in: I can't believe its even being asked).
My rebuttal question is: why cut the PO for two different brand machines?
If a shop needs two spindles? And they are pulling the trigger on new iron? Why would they park two completely different brands on the floor?
You haven't shared what models. So, we don't know if one MFG offers capability the other does not.
But, if this is an apples-to-apples capability two machine purchase? What could the reason for getting one of each possibly be?!
If it is to test each machines capability for yourself? Then send the other packing on down the road? Save your headaches, and buy the Brother!
 
The pull-stud is the life's-blood of a bt-30 spindle. I feel this is kind of a crazy question. (crazy as in: I can't believe its even being asked).
My rebuttal question is: why cut the PO for two different brand machines?
If a shop needs two spindles? And they are pulling the trigger on new iron? Why would they park two completely different brands on the floor?
You haven't shared what models. So, we don't know if one MFG offers capability the other does not.
But, if this is an apples-to-apples capability two machine purchase? What could the reason for getting one of each possibly be?!
If it is to test each machines capability for yourself? Then send the other packing on down the road? Save your headaches, and buy the Brother!
I guess I should clarify my position here. We are looking at a DMP 70 w/ all the options including the 5 axis package. As well as one or two S500xD1 from Brother. At the time of looking at the DMP the U500 was not out yet and overall the DMP is still a better buy for full 5th capability given that it actually is full 5th (something I need) and has direct scale feedback etc. I agree for purely three and four axis applications the brother is very hard to beat. But in terms of 5 axis capability DMG has been doing that for decades now. Plus we already have a 65 monoblock in the shop so we are familiar with DMG.

My question posed about pullstud interchangeability is merely a speculation at some rumors that I've heard from others before and by no means a recommendation to do so...

Ultimately If I got to swap studs its not a deal breaker just a convenience thing.
 
Don't mix the pull studs.

Get them from two different brands with cosmetic differences. For example, get your 60-degree studs from Maritool which are all black, and get the 45-degree studs from another brand that are half black/half bright.

The DMP might not allow you to use the wrong studs anyway. Our NHX machines will alarm out if the wrong stud is used based on drawbar position.

As for the Brothers, the tool changes are so fast that you'll end up programming those machines with a lot more tool changes per part on average, so it's not somewhere you want to take any shortcuts.

Another idea: get the DMP with an HSK spindle.
 
Last edited:
Another idea: get the DMP with an HSK spindle.
I considered, but I'd rather not add another taper to my already long list. I already have Cat40+, Cat50, HSK63a, and now BBT30.

Also I'm pretty heavily invested into the regofix powrgrip holders and buying another assortment of those for another taper adds up way faster than you'd think at $300-500+ per holder...
 
If you paint a thin line around the holder in the external groove, 1/8 wide, yellow for one machine, nothing for the other, I don't think you'll effect the balance

Your going to have to accept at some point the wrong toolholder WILL go in the wrong machine. That's just how it is. I've had a few "f'k me, how the f' did I do that" incidences recently, it happens.
 
I have 20 year old specimen which has ran mix of both angles just fine, so it will not break the machine right away.
 
I have 20 year old specimen which has ran mix of both angles just fine, so it will not break the machine right away.
Same, my current BT30 machine is 33yrs old and has run both for decades without issue. I don't personally mix them, but know the previous owners did as the holders that came with the machine were mixed. All the Speedios at my old shop were mixed as well. As soon as I saw they were also using the "wrong" ones I purged all of them, but we never had any issues with either. I don't advise this, but it doesn't seem to make a big difference aside from some retention force. The contact area for the balls is nearly identical, at least on the ones I've seen.
 








 
Back
Top