Roll bender build. Update pics post 28

[jackalope]

Originally Posted by rdn2blazer

The center pressure roller as I call it will have as close to zero side to side movement as possible. There will be a guide keyed into the plates on both sides locking it into place.I'm going to use Delrin so it slides on the Aluminum plates to minimize friction, but there will be only a couple thousands so the pressure roller mount is not pinched between the plates. All I can say is IF I'm wrong and my design just does not work, I will gladly admit to you you were right.
BUT!, If my roller works flawlesly, your going to have to eat your words my friend. I have 20 years machining experiencs and have developed, designed and machine tooling hundreds of times for hundreds of machine jobs and grinding fixtures for cnc milling and turning and conventional mills and lathes, and plasma spray turn tables. Also, welded many tooling tables and jig & fixture setups. I think I know a thing or two about tool design and what will work and what won't. If I didn't have confidence in what I was doing I wouldn't do it. I don't know one single person who has bent up a full cage manually without software without wasting some tube. I have not lost one single piece of tube, or misbent ANY bends in my quite extensive cage. I think my ability speaks for itself.

rdn,
Perhaps if you had shed a smidgeon of light into your experience as well as started the topic with some of the information included in the above comments, I would not have been so upfront. Your design, as you have explained it, "sounds" flawed. If you have just been misinterpreted because you left out vital details, then I apologize.
I was only trying to be of assistance. After all, you posted the question/comment about your design. If there were NO concerns about it's design, I ASSume you would not have posted it here in the first place and just gone ahead and made it.....being that you have confidence.
BTW, I get zero satisfaction seeing someone spend a lot of time at something and fail. I have been there myself and it is discouraging. All I will say is best of luck and please report back with your finished product. I am anxious to see and would MUCH rather see it kick ass than suck! ;-)

Grant

[Shox Dr]

Jackalope. I couldn't agree more. There are two types of lessons; Expensive ones, and cheap ones.

The expensive lessons are the ones you learn your own mistakes .

The cheap ones are where you learn from someone else's.




I have sayings all over my workshop, one of them proclaims; If you don't learn something everyday, then you haven't been listening. Worth remembering I think

(no offence Rdn)

[rdn2blazer]

Originally Posted by jackalope

rdn,
Perhaps if you had shed a smidgeon of light into your experience as well as started the topic with some of the information included in the above comments, I would not have been so upfront. Your design, as you have explained it, "sounds" flawed. If you have just been misinterpreted because you left out vital details, then I apologize.
I was only trying to be of assistance. After all, you posted the question/comment about your design. If there were NO concerns about it's design, I ASSume you would not have posted it here in the first place and just gone ahead and made it.....being that you have confidence.
BTW, I get zero satisfaction seeing someone spend a lot of time at something and fail. I have been there myself and it is discouraging. All I will say is best of luck and please report back with your finished product. I am anxious to see and would MUCH rather see it kick ass than suck! ;-)

Grant

I don't have to explain every single detail down to the last possible explination so everyone could understand what it is I was doing. I gave a basic overview of what it is I'm trying to build. If you read my post the only thing I even asked for help with was the sprocket setup as stated here

Quote:
Where I might need help is in selecting the proper size chain and sprockets. Not sure what size I need/should use. I thinking a duel sprocket on one shaft so I will have a chain to the one shaft from the motor and a chain to the next shaft from the first shaft. OR, I could do single sprockets and have a chain go around all three sprockets. Not sure which is best for adjustability sake. Not to mention torque sake. So what say OFN regarding my fantabulous 3 roll bender idea/build????
End Quote.

You, right away said my roller design was just not going to work what so ever based on blah blah blah. You talked about how it was going to mis-align and so forth from the load exerted by the pressure. I never once said I needed help with that particular portion of the build. No I did not go into spicific absolute detail regarding that part of the build. No reason to.

This is just the first stage of the build, and it's admittedly a winging it build like I usually do when I get a wild hair up my arse. My winging it builds have been the best things I have built. I don't sit down and draw out every single detail like an Engineer would cause I just don't like to work like that. I like throwing caution to the wind and going for it. Never had an brain storming idea fail me yet. Prefer letting things go with the flow, brainstorm as a build happens, think outside the box as I said.

Also, I don't have to explain all about my experience everytime I post up a build. It's nobody's bussiness really how experienced I am. You could have just said, cool, good luck with your build and left it at that. I appreciate your comments all be it you were, right off the bat cutting down my build without allowing me to get farther into it before you hammered me on it. Yes, I AM confident with my build, but as I stated in my thread title I might need some help, and I did state in my first post what spicifically it was I might need some help with. SO please, next time you ASSume your offering help, please, make sure your offering help on specifically what was requested. No need to be bitter or offended by my replies either. I don't think I was being harsh in return.

[entropy]

Originally Posted by jackalope

rdn,
Perhaps
SNIP<
Grant

Originally Posted by rdn2blazer

I don't have to
SNIP<

Ok, can we call this a draw, reserve judgment for the completed project?
Because, I am sure that I ain't alone in thinking you both have valid points and I just want to see the damn bender!!!

'z all around.
E

[TheBandit]

Do I understand correctly that the problem jackalope is concerned with is the center roller's tendency to rotate off axis if it's mounted in a catilevered configuration?

I think a sketch of the design would really help.

[jackalope]

Originally Posted by rdn2blazer

...... So what say OFN regarding my fantabulous 3 roll bender idea/build????

This is where I got the idea about imput from...

Clint,

You are spot on with where my concern is/was.

I have no stake in the success or failure of this. As I mentioned, I hope this works. I will stay outta this as you say you are sure of your design. Best of luck!

[TheBandit]

If that's the problem, I think the design is going to dictate how well the roller stays on axis. I would think a 1-1/2" shaft with only the die thickness of stickout would be okay if very solidly supported by the frame (for example, solid mounted with preloaded tappered bearings). Having the roller moving up & down means you'll have to have a very tight or tightenable assembly to keep it in place. It will also be very important for the die to have a solid fit on the shaft or be bolted to it to prevent movement within the shaft-OD-to-die-ID fit.

It might not be a bad idea to put a flat surface on the end of your center roller shaft so you can attach an angle finder or some means of measuring to see if it's going off kilter.

I really look forward to seeing the design whatever it is. We're all here to learn from eachother whether we agree with eachother's ideas or not, we may as well share them. Personally I don't think there's enough information on the actual design yet to judge how well it will work, but I think the points that have been brought up are good ones to consider.

I really want to make one of these too some day so do a good job and I'll copy your design!

*EDIT* Another idea that I think would be cool would be making one end a roll bender and somehow make the other end a bead roller. Or even just make some bead rolling dies for it and set it up somehow so you could make flanges and whatnot.

[rdn2blazer]

Here is what I have so far. Work in progress. Bearing block bolts need to be cut as the load will be on shank, not threads. Still have parts to make. I made a custom cutter for the radius for turning the roller die set. Starting with a 1 3/4 set. Still need lots of parts. It's coming together. This is the adjustable idea I had with the holes to adjust the bearing blocks. The two holes on each side of the slot for the pressure roller will be C'sunk so I can use a flat head from the inside so the pressure roller setup wont hit the nut if I were to use a bolt and nut there. Thats only when I'm using the roller close which I don't know if I will unless it's small tube.

[rdn2blazer]

click on the pics, that should open up a bit bigger.

[TheBandit]

Lookin goo so far. Gotta love the dining table for buildin a bender - did somethin similar myself a while back. Be sure to put some antisieze in those tapped al holes. How are you tapping them? That was by far the most time consuming task with my build. A CNC mill would make life a lot easier.

Keep up the good work.

[rdn2blazer]

Originally Posted by TheBandit

Lookin goo so far. Gotta love the dining table for buildin a bender - did somethin similar myself a while back. Be sure to put some antisieze in those tapped al holes. How are you tapping them? That was by far the most time consuming task with my build. A CNC mill would make life a lot easier.

Keep up the good work.

Thanks man. All holes are thru for a bolt and nut to save me tapping time and trouble. I have to use about 9" grade 8's to get the shank length I want. I will just cut off the extra long threaded portion. The bolts in the pics are only 7" long and just for pic purposes, don't have the correct length yet.

[rdn2blazer]

Here is the two I have machined so far. In the one guys build he used a material called Nylotron, a type of Nylon plastic. I used Delrin, It's strong plastic I'm hoping will work. If I have to go steel dies I will but I think these are robust enough that they will work. I have to broach them for a keyway. I'm not going to broach them thru the full length of the bore though. Since the radius cut is the thinest wall thickness area at 3/8 inch I will broach the 4" diameter area X's it's length. Less likely to crack. The groove it exactly 1.750. I tried some DOM in the groove and it fits nice and snug so it won't be trying to spread it and split the roller die. Making the third one tonight along with some other parts for the build.

[idahoaj1]

looks really good... keep the pics and updates coming!!

[BAILEIGH INC]

Nice build

[CAPTAIN CNC]

Well..... I just read this whole thing and i dont see what the big deal is. I mean i understand the concept of the problem that is being referred to but there are mechanical ways of COMPENSATING for the CL of the top roller to become out of wack under pressure. For the most part i agree with MOST of what has been said but if worst comes to worse why couldnt ya engineer it so the pressure application was applied to each side of the roller in question individually? Equal turns per side = equal pressure? Then maybe a dial indicator on a base that slides to check the height of each side of the roller. Or perhaps 2 indicators fixed somehow semi-permanently to allow visible confirmation that the roller stays on its CL.

I dont see any reason for the pissing contests either. The man is gonna do as he wants to do so if it were me i'd be looking for more constructive criticism. I mean it's not as if he's working out kinks in some product he plans to sell. He just wants a tube roller, so do i, so he's goin about it the best he knows.

So far everything looks good to me. You may have to make some adjustments/additions to the design later but i say go for it. I too am VERY interested in how it turns out now.

I see where Grant is coming from too though. He's just tryin to give the advise he can based off tryed and proven methods and results it sounds like. But i wouldn't let that discourage me. Do it to it!!! Lets see some rolled tube...Good or bad. We'll all help diagnose if something is amist.

No offense intended to anyone... Just my opinion.

[CAPTAIN CNC]

Afterthought:

The indicators could serve double purpose for more accurate bend repetition as well.

[rdn2blazer]

Originally Posted by CAPTAIN CNC

Well..... I just read this whole thing and i dont see what the big deal is. I mean i understand the concept of the problem that is being referred to but there are mechanical ways of COMPENSATING for the CL of the top roller to become out of wack under pressure. For the most part i agree with MOST of what has been said but if worst comes to worse why couldnt ya engineer it so the pressure application was applied to each side of the roller in question individually? Equal turns per side = equal pressure? Then maybe a dial indicator on a base that slides to check the height of each side of the roller. Or perhaps 2 indicators fixed somehow semi-permanently to allow visible confirmation that the roller stays on its CL.

I dont see any reason for the pissing contests either. The man is gonna do as he wants to do so if it were me i'd be looking for more constructive criticism. I mean it's not as if he's working out kinks in some product he plans to sell. He just wants a tube roller, so do i, so he's goin about it the best he knows.

So far everything looks good to me. You may have to make some adjustments/additions to the design later but i say go for it. I too am VERY interested in how it turns out now.

I see where Grant is coming from too though. He's just tryin to give the advise he can based off tryed and proven methods and results it sounds like. But i wouldn't let that discourage me. Do it to it!!! Lets see some rolled tube...Good or bad. We'll all help diagnose if something is amist.

No offense intended to anyone... Just my opinion.

Thank you. Bottom line IF having the outside dies cause deflection cause their not supported on both ends and the 1 1/2 in shafts flex enough to cause misalignment. I will just used the dies in the center like everybody else does. I got the pressure roller die machined up. Had to make a custom 1.750 full radius tool bit to machine these.

This of course would never work in steel. But the Delrin cut nicely even with this much surface area. Tool bit is just a piece of 1018 CR steel. I used a live center and had the material securely chucked in a 4 jaw chuck. Material was out of round so a 4 jaw was the way to go. Luckely it was oversized at about 4.100 dia so it more then cleaned up at 4.000. Just did a straight plunge cut and had to move .010 each way after the center was cut out and kiss it with some 400 sand paper and it smooth. Going to get more parts machined up tonight.

[rdn2blazer]

Got what I call the saddle assembly for the pressure roller finished as far as I can till I get more parts. I need the Acme threaded rod and tapered bearing before I can drill and bore for the mounting of the acme rod. Also need the 1 1/2 shafts for the dies now. It's close to being finished up though. Also left the side plates long so I can cut to length and radius the ends to match the radius of the 4" dia roller. Since there will be nothing but down force on the plates, I mounted them underneath the top plate with fasteners and precision dowell pins. Instead of side mounting them and relying on the strength of the fasteners to hold the load.

[rdn2blazer]

Have a little bit of an update. Got a few things machined and a couple things I ordered in. Machined the second set of rollers that will be the Outboard set of dies. The ones marked #1, 2, 3, are the inboard set of rollers and #4, 5, 6, are the out board set. The only, I guess some might consider bad thing is that some of the rollers are inboard and outboard location spicific. It's not a big deal really to me. If this Delrin holds up without cracking, cool, there easy to make. #3 and #6 rollers are the same, those can go either inboard or outboard.

As you can see the #1, #2 rollers are 5" wide made to fit inside the plates, while #3 fits inside the pressure saddle assembly. The Outboard rollers are the same width as the one for the pressure roller assembly, but a narrower design then the 5" so as to minimize the overhang load on the shafts since they won't be in double shear. You can see I even counter bored the #4 & #5 dies to slip over the bearing block sleeves to get the centerline of the radius as close to the support bearing as possible. The two slots on the opposite side are how the outboard rollers will be driven. Both #4 and #5 rollers have C'bore's on one end and slots on the opposite end.

I machined the set screw coupling in the pic to have two lugs or drive cleats that engage into the slots in the two outboard drive rollers. I machined both ends of the coupler to have teeth and I'm having a buddy EDM it in half for me so I don't lose material, not that it would be much if I band sawed it in two and faced off both halves in the lathe or parted it off on the lathe. The interupted cut would be hard on a cut off blade with the keyway in the bore though, to dangerous to do IMHO. so EDM it was and it's not costing anything anyways. The minor rust on the coupling cleaned right up too.

I got my 1 1/2-5 ACME threaded rod and Bronze Acme nut in. Have the cut it to length and mill one end to a hex for a socket to fit to drive it and the other end will get turned to 1.000 to fit the Timken tapered bearing and bushing in the saddle pressure assembly. I also need to drill & bore the top plate for the bronze Acme nut to be pressed in to it.

[rdn2blazer]

The pressure saddle will have these Delrin, what I call slide guides mounted to the sides, these will slide against the main Aluminum plates instead of having steel against Aluminum causing wear on the Aluminum plates. The saddle assembly and slide guides were left long to figure out the best length once the threaded rod was bolted up. The machining there still is in the future design stages. Also the fit of this assembly is just a few thousands less then the span of the Aluminum plates so there will be no side to side deflection. Also the reason for the large diameter Acme rod, it's good and robust size will minimize any deflection.

The slide guides will mount using counter sunk flat head fasteners of course. The white washer is a 1/8 thick Delrin washer that will go between a steel washer and the bushing in the saddle. I'll turn a 1" fine thread and 1.000 diameter on the Acme thread for it to bolt to the saddle assembly. I'll use a Nylock nut there so it won't back off.
There will be just enough torque on the nut against the steel washer to secure it to the saddle assy, nut and steel washer will rotate against the Delrin washer. Some tention on the nut will be over powered by the leverage on the crank handle or ratchet when adding pressure to the pressure roller.