Chicago Dreis&Krump Box&Pan brake rebuild

Just found this thread. Nice buy Paco.

I started to vote for the reinstatement of the oilers but, after thinking about it a little more, I'm not so sure.

How much service is that brake going to see in your lifetime (another 50 years). Would you ever wear them to the point that replacement was called for?

What are the trade offs?

Will more oil add to the life of the joint? I would expect so, as long as no contamination is introduced in the oiling procedure. Contamination isn't much of a problem considering the resident PM mechanic.

You could band saw a slot, perpendicular to the axis, at mid length and about half way across each bushing. Then cut spiral reliefs in both halves with a rotary tool to distribute the oil. Remove all burrs and shavings and there you go.

I think I'd reinstate the oilers, but I don't think it's a big deal either way.

Most importantly, there is about zero chance the brake will ever be abused (in your shop) so it's going to last a lifetime either way.

Regarding the leaf alignment, I don't understand where/how/what the problem is. When you revisit that area of the refurbishment please clarify what is to be aligned and what is out/where. Thanks, as always.

I like the idea of oiling joints, fresh oil flushes out particles from wear thereby removing abrasive material. Drilling the one piece bushings isn't going to give you a reservoir. I'd be tempted to cut the new bushing and make two that would install as the old ones did.

Greg

Thanks for the feedback guys, I think creating a two piece bushing might be the way to go. If I was to saw a slot the bushing would likely collapse (at the slot) upon pressing in resulting misalignment/binding of pin (I think). The contaminants would result from normal ware over the course of long term use so flushing by way of outside oil would work via ball oiler. I'm not 100% I need to grove the inside of the bushings as this could retain/pack contamination over time. The old bushing journals where packed with abrasive doodoo.
The distance from the ball oiler to the bushing is almost two inches, I was thinking the 1/4" hole (between oiler and bushing) in the main housing and a 1/8" hole through the bushing might provide a nice reservoir allowing the bushing to remain one piece. This would probably be enough to flush it on periodic scheduled maintenance.

Probably over thinking the whole thing, but the next guy that owns this machine will be able to place it in immediate service unlike myself.
Always room for improvement and I continue to learn by asking.

Extropic, The adjustments come by way of turn buckles found on rear of the top clamp and bottom table. Other adjustments are from the top clamp center and folding leaf center. the machine should have a slight crown to both the top clamp and apron when static. This provides an even bend throughout the bent/broken piece. I'm hoping my previous failure to achieve this was due to sloppy joints/pivot (all eight of them). Thanks for the Oilite link you provided. Unfortunately, I don't know the exact composition of the Oilite bushings Dreis & Krump sell. A good read non the less.

Hard to read but I have a hard copy coming:
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Gentalmen,thanks again for taking the time to help me out.

Happy Thanksgiving!

Paco
 
The 3/4" X 12" x 72" piece of cold rolled I ordered arrived late yesterday. I Plan on using this material for the finger extensions, Turns out all but one were bent making it impossible to line up the nose bars. Theres a total of 15 fingers (4) 3", (2) 4",(5) 5" and (4) 6" widths. Industrial Metal Supply had 3/4" x 10" CR but I required minimum of 10.5" wide so the next up size was 12" wide. (bummer). I was able to cut the bar flat on the Ellis 1800, It was pretty much maxed out but did a nice job cutting very close to square. I was able to get +/- .003"from end to end on a 12" cut so was happy with that.

This bar was a beast coming in at 30.600 pounds per foot so the 72" piece weighed a hair over 183.5 lbs. The hardest part was pulling it from the bed of the truck and onto the fork lift, the rest was cake as the input feed rollers make it very easy to feed the saw.

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The Ellis 1800 was barely big enough. The max height for this saw is 9" so flat was the only way to cut this.
It took about 4 minutes per cut and had a nice steady chip production. The saw is designed to be used dry, but with this much blade contact, a shot of WD-40 every 30-40 seconds made a world of difference. The blade was cool to the touch the entire time so the feed rate was right. The quality of the swarf also confirmed the feed rate. They looked like tiny cork screws.
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These are the finger extensions I'm shooting for. This one was the only one that survived the abuse. The rest are toast. The OEM extensions where made of Hot Rolled bar, but I wanted true flat bar to machine and the CR is a bit stronger. After the top/bottom is machined, I will lay out the two threaded holes and the nose bar counter board hole (top view).
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The bottom required more machining than the top as the nose bar clamps are involved.
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Heres the stack of extensions. Still need to de-burr and cut the 40º nose angle. I think the Ellis could provide a straight cut now that the pieces can be clamped on edge. I probably set up a stop so they all end up at 10.5"long after the 40º cut. The blade should like the 3/4" vs the 12" contact hahah.
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Close up of the cut finish, pretty pleased with the Bahco blade. They claim this blade pitch does it all, I guess they weren't lying.
I've been using this blade for the better part of ten months and have cut plenty of stock.
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Not exactly accurate but does represent how the extension (finger) is used.

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Thanks for looking, and happy hump day!

Paco

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Thats an impressive piece of CR Paco. Interesting finger design, really like the hardened ends.

Greg
 
Thats an impressive piece of CR Paco. Interesting finger design, really like the hardened ends.

Greg

Yea, it was the largest CR flat bar I have ever delt with. The nose bars are semi hardened. I’m hopeful a face mill will clean them up. Dreis gets $21/ inch for those. The brake needs a ton of TLC, but a new 6’ box and pan brake is more than I can afford. We’ll get there...eventually.
 
The nose bars cost about what I paid for my 48 inch brake a number of years ago.

Greg
 
I decided to square up the flat bars before attempting to cut the 40º nose angles. Although very close and consistent, they still varied slightly.
I used a flat surface to to square up the factory ends and clamp two at a time then set them up for a face mill pass. I only have two shell mills and limited experience using them on steel. One is a four cutter that takes individual carbide tipped cutters that is manually indexed (3.5"), the second one is a 2.5" five cutter that uses TPG style inserts. Both of these cutter came with the mill as a package so not items I purchased individually with intent.
I had used the larger cutter on aluminum with very nice results and gave it a try. A face shield and long sleeve welding shirt became my best friends as hot chips where flying in all directions.

Here is the initial squaring using the factory edges prior to clamping. Poor mans granite surface;).
Incidentally, I purchased the large set up block back in 2002-3 on eBay back when plenty of good deals could be had (not so much now).
I want to say I gave $20 for it and its flat. I use this on the press often when pressing smaller bearings.
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Clamped the bars and set up on the mill.
The saw really did a fantastic job of cutting considering the length, but with a 12" cut they all had a slight .002-3" bevel that required clean up.
They will eventually be mounted in the vise flat for milling the steps on the ends. The sides need to be true for a good setup.
Verified the table and vise tram prior to this set up.
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The backlight made it easy to verify the precision square to the factory edge.
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No light showing after adjustment. Ready for the first pass. The right side on this particular piece was .001" wider than the left side (due to the bevel cut).
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First pass using the larger shell mill at 700 RPM and 10 ipm (power feed) with a depth cut of .020"
Climb face milling, is this correct?
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Re-clamped flipped and used the base of the vice for indexing the good side. A quick check with the square set up was satisfactory.
The carbide shell mill was tired starting off and the second cut finish looks like doo-doo compared to the first.
The second 6" pair of finger extensions where set up and I opted for the smaller 2.5" five cutter shell. This one uses TPG inserts that can be rotated three times. Well those where also tired from the start and had already been rotated three times. Poor planning on my part.
The finish was excellent compared to the second pass with the first cutter. All four 6" extensions are with in 1/2 thou.
I was able to get three of four sides of the 5" extensions before the finish surface began to diminish. The chips where glowing at 800 RPM and 10 ipm with a depth cut of .005" The inserts where done. Work stoppage until the new inserts arrive. I found some NOS Kennametal TPG 324 (1/16" radius) Grade KC730 (eBay). The old ones where unknown maker and more than likely a C2 grade. Inserts still confuse the hell out of me. It took me at least three hours to figure out what I had to begin with. Its all about learning, but inserts charts give me a headache:bang head: .

Heres a shot of the finish.
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The second shell cutter is a 2.5" ATP.
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14 sides down (5" pair still on the mill ) and 12 to go.
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Question for you experienced face mill users, would it be possible to utilize the same process to mill the the steps required, or will the interrupted cut be a problem for this type of cutter?

One end of top surface require a step. The opposing end gets the 40º angle cut (band saw).
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The bottom gets both ends step cut. I have end mills but wondering if a face mill cut is appropriate.
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That all the progress on the Dreis & Krump for now. Any advice is greatly appreciated. It's all about learning and not getting hurt.

Gonna take it easy today and take my wife to the Zoo for an evening special event.
Never been to our local Zoo at night so looking forward to seeing the nocturnal critters. Our evening temps are nice this time of year too.

Turn and Burn!

Paco

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I have an indexible 1 1/4 inch end mill with an R8 shank that uses 2 triangular inserts. Would work great for the steps. This would be a great application for a shaper.

Greg
 
I have an indexible 1 1/4 inch end mill with an R8 shank that uses 2 triangular inserts. Would work great for the steps. This would be a great application for a shaper.

Greg

I've always been intrigued by shapers. Watched some videos of them in action, like the rhythmic sound they make. Neve used one or even touched one for that matter.
This is the cutter I used and considering for the steps. It is a 90º square shouldered, just concerned about the performance on interrupted cuts for the narrower steps.
https://www.mscdirect.com/product/details/03122975
 
Thats the larger dia version of mine, use it to cut shoulders often.

Greg
 
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