Power Drawbar Accessory

[Geswearf]

My edit did not stay, and expanding on DavidR8 -

You money is better spent on tooling (endmills, cutters, drill chuck, drill bits,) work set up and hold down (Vise, parallels, T-slot clamp kit), and measuring (calipers, micrometers).

Thanks, I understand the need for tooling. I'm not a complete beginner. As I've said elsewhere, I've used a full sized Bridgeport and Jet mills a number of times. I've had HF's bottom end (smallest) mill for a few years and have used it on steel, aluminum and plastic. I even used this mill to rough cut out three knives (O1 steel) and while my modest collection of end mills is adequate for my purposes until now, I know I'll be buying more in the future. I have a Drill Doctor and use it to sharpen my drill bits, both a wheel grinder, a 2 x72" belt grinder, a number of dial indicators (bought used, Mitutoyo, Starrett, General), mag base, three calipers (one digital, one dial, one vernier), hold down kit, squares, scribes, starrett precision level, shims, etc.

Having used mills in the past, I know the tedium of hand cranking, and power traverse is, imo, mandatory. I was inquiring about the power draw bar because I'd need to get to the top of the machine in order to change bits. Were I 6' tall this would be no problem, but maybe in my next life. For now, though, I'm probably going to pass on this accessory because of the cost and great suggestion from DavidR8. I already have air wrenches and impact tools for automotive work.

I fully expect to immediately spend a couple of thousand dollars on tooling - a good vise, collets, drill chuck, v blocks, fly cutter, parallels and setting up the machine. I appreciate your list - I'm taking notes and building my own list of accessories I want, tooling I'll need sooner than later, and vendors who sell good tools. That's why I'm here asking questions (some stupid, some not so much). I've been a tool nut for years and have told a lot of friends that the wrench or screw driver they handed me is a sorry excuse for the genre. Only clarification I'd add to your comments is buy once, glee a lot. I don't cry over the cost of a really good tool. I take pleasure from using and operating good things, but separate out what is excellent from what is truly superlative for an exorbitant price. For example, you can buy excellent Lie Nielsen hand planes for a few hundred dollars, or you can buy a handmade Norris style plane for $5 or $6,000. From what I have read, the latter are truly a joy to use, but will not, in the end do a better job than the former (I'm a woodworker, too).

Your list of utube guys is particularly helpful. It is nice to separate the wheat from the chaff before I start watching.

 

[MG&L]

Geswearf,
Sounds like you have the proper mindset. I'd like to think I am as in tune to the needs and priorities of my shop, but sometimes get pulled into the "nice to have's". Not that those are a bad thing, but we all have our budgets, both large and small. I did opt for the power draw bar just last year, and praised the day I had installed it and every day since. My shoulders are not what they once were - arthritis has set in and doing anything higher than having my arms parallel to the deck is, well..., not enjoyable. I will be getting my first (right) shoulder replaced in January, then as soon as I am approved, I will have the left one done. Maybe after that point, I will be able to return the PDB for a full refund and put that $ toward my tooling list. Hmmm, well it sounded more reasonable in my head than after I had typed it out.

 

[Sticks]

Geswearf,
Sounds like you have the proper mindset. I'd like to think I am as in tune to the needs and priorities of my shop, but sometimes get pulled into the "nice to have's". Not that those are a bad thing, but we all have our budgets, both large and small. I did opt for the power draw bar just last year, and praised the day I had installed it and every day since. My shoulders are not what they once were - arthritis has set in and doing anything higher than having my arms parallel to the deck is, well..., not enjoyable. I will be getting my first (right) shoulder replaced in January, then as soon as I am approved, I will have the left one done. Maybe after that point, I will be able to return the PDB for a full refund and put that $ toward my tooling list. Hmmm, well it sounded more reasonable in my head than after I had typed it out.

Id say that even healthy, the PDB is a have it, not getting rid of it...ever... kind of thing.

Not having it and not knowing, then one can keep going without. It's like a keyless drill chuck (gateway drug to lazy). Hard to go back to regular, and cuss the keyed ones when you do have to use it.

 

[Geswearf]

Id say that even healthy, the PDB is a have it, not getting rid of it...ever... kind of thing.

Not having it and not knowing, then one can keep going without. It's like a keyless drill chuck (gateway drug to lazy). Hard to go back to regular, and cuss the keyed ones when you do have to use it.

I've used a power drawbar (at that local college's shop with large Jet knee mills) and for sure it is convenient. I watched a machinist use a wrench on his PM935 and it did not look onerous. Having used both key type and keyless chucks on cordless drills and drill presses, I don't agree with you. Using a key is easier to lock and unlock the chuck than a tightened keyless type. I've had to use channelocks on occasion to unlock the keyless chucks on cordless tools. It may be that a higher precision keyless will perform better than a cheap key type, but I don't know.

Some of this strikes me as the power seat in a new car vs old fashioned seats that required the driver or passenger to reach down, pull the latch release and move the seat to the desired location. I never had a problem w/ the manual seats and agree that power versions are easier to use. But are they necessary? My take is a resounding 'NO'.

 

[FOMOGO]

I used a cheap a cheap 3/8" drive air impact for years. Just a light zip on/off, never had to use the brake or change to low gear. The impact recently died after years of service, grabbed my 20V Makita impact which works equally well. Actually better as there is no air hose to deal with. Always planned to make something permanent, but it seems to be forever on the some day list. Mike

 

[Winegrower]

A power drawbar is not a necessity, more of a luxury.

It can also be a pain to use. A friend has a Bridgeport with a power drawbar, and I find it a nuisance. You need air, the quill must be returned to full up, the tightness is preset and can be too loose but it's not known until the end mill pulls out, the torque can smear out the collet locator pin and require removing and repairing, it's noisy and slightly startling...stuff like that. I suppose if you just can't reach the drawbar it is a lot more necessary, but I have my Bridgeport up on 4x4s, installed a 4" riser, and it's still reachable. I'm about 75 in inches and years, full disclosure.

 

[a.smith]

The priest tool power drawbar doesn't rotate to tighten during normal operation. The drawbar is preloaded by tightening it against a stack of spring washers. When you activate the drawbar to change a tool, a pneumatic cylinder presses down on the spring stack which releases the tool. They are pretty quiet.

 

[Geswearf]

The priest tool power drawbar doesn't rotate to tighten during normal operation. The drawbar is preloaded by tightening it against a stack of spring washers. When you activate the drawbar to change a tool, a pneumatic cylinder presses down on the spring stack which releases the tool. They are pretty quiet.

Seems to me that this should be pretty easy to use a commercially available air cylinder, a powerful spring and maybe a bellcrank to make your own. The bellcrank would allow the cylinder to be mounted off to one side to decrease the height above the top of the head. (Think rocker arm like under the valve cover of your car.)

 

[a.smith]

Seems to me that this should be pretty easy to use a commercially available air cylinder, a powerful spring and maybe a bellcrank to make your own. The bellcrank would allow the cylinder to be mounted off to one side to decrease the height above the top of the head. (Think rocker arm like under the valve cover of your car.)

Absolutely. It's not a complex or high precision device once you have a commercial air cylinder that can deliver enough force.

 

[koenbro]

Yeah the Priest PDB uses a commercially available air cylinder, an air solenoid, spring washers, a draw bar, a cheap R8 collect, and a switch to prevent activation when the springs are not locked. He machines a plate to connect the parts to the casting, and adds a plastic box for the electric connectors. Once you price out the parts you are pretty much in the ballpark of the price, but of course I would go upmarket in quality compared to what he packages - a proper, flat Tormach R8 collet, McMaster air fitments that don't leak, etc, so it would end up more expensive. For those who know their way around the components, you can surely make your own -- that was not me, so I bought the package.

Overall an air PDB, when it works, is a life changer, and I will never go back to wrenching. Someone above mentioned that the TTS is a hard no for them. I respect that but for me consistent tool length registration is a must, and TTS does that.

YMMV but the PDB + TTS is convenient, fast, and gives reproducible tool heights.