Tool holding on a Bridgeport

I was referring to using power to unscrew the drawbar. It still takes a wrench to break it loose and a tap to release the taper. I made a wrench/hammer similar to this for the purpose.
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Might not be worth it for some, but I got pretty quick with it. Just be sure to remove the wrench before bumping the power, just in case.
 
I started out with a ER32 collet chuck not knowing they made R8 collets (pre internet), used it for years. Since I found out about R8 collets I could count on one hand the times I've used the collet chuck, a set in 1/8ths will as said hold 99% of your end mills, I have 2 out of hundreds that are 7/16 and 9/16th. Though you have to make room to install it I use R8 shanks on everything else,
I have a 10 inch riser in the mill, climbing up there got tiring, made a power drawbar a few months ago, think I posted it in the "What did you do today thread", its a god send. With it I could see no reason for quick change tooling.

Greg
 
While I have an ER-40+R8 attachment like mentioned above, I am looking towards a set of R8 collets directly.
There are 3 advantages:
a) lower runout
b) more nose height
c) more rigidity.
 
ddickey said:
Didn't even think about the straight shank drill chucks. Duh
Click to expand...
My clue was from the sheer volume of straight shanked chuck's sold by eBay seller "stm_surplus 2". I figured Morse taper was for lathes, R8 for mills. Then dawned on me to put the straight shank in a collet.

Bruce
 
I totally understand the reasoning behind the use of straight shank tooling. BUT, when using straight shank tooling into a collet you have increased the runout uncertainty. The less you have going on to hold your tooling the better the accuracy. For this reason, I do not use straight shank tooling into a collet. I go from R8 directly to chuck or whatever. And I do not have and don’t see the need for an R8 to ER32, very sorry to say…sorry guys. And for some reason, I did buy a metric set of R8’s. I don’t know what the hell I was thinking? It has just been collecting dust! I also have several sets of Bridgeport R8 back-up sets too. They also have been collecting dust. One set of Bridgeport collects well cared for will probably last your lifetime. And you really don’t need a back-up set(s)…Dave
 
I have R8 collets and R8 endmill holders, but the ER32 collet chuck probably gets the most use. It is more convenient to change tools at the spindle nose than by using the drawbar. A big advantage of the ER collet system is the clamping range of the collet, about 1mm. They cover sizes for which R8 collets are unavailable.

I can not use a power drawbar because I have some attachments that clamp to the quill. That requires a socket wrench to reach the drawbar. The power drawbar setup would prevent that.

Each toolholding system has its advantages and disadvantages. Figure out what works best for the way you want to work.
 
I have no problem reaching my drawbar. I started out with a wrench and then went to an electric ratchet from HF. I really like the electric ratchet.
 
Firstgear said:
I have no problem reaching my drawbar. I started out with a wrench and then went to an electric ratchet from HF. I really like the electric ratchet.
Click to expand...

That’s what I ended up doing myself. I don’t have enough space to build a power drawbar using air impact wrench. I did purchase a Milwaukee just to cut down on batteries and chargers


Sent from my iPad using Tapatalk
 
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