# When delicate stuff has to be done with something HEAVY ?



## graham-xrf (Dec 6, 2021)

The phrase is so concise - "put the inked surface against the work". For much of what we do, it's put the work down onto the inked surface plate, but when one has to manhandle a straight-edge reference surface onto the ways of a lathe bed, and it weighs 40kg+  (near 88lb), we have to contrive some kind of hoist or suspension jig. You can't reasonably just have it swinging about on a car engine hoist just any old way. One needs to be able to lift and tilt it exactly right, and lower onto the work spotting surface, make the print, and lift off without smearing.

I can only (just about), dead lift it (a bit). Moving it about at all will strain a valve within (me) somewheres, and to carefully place it it to take good measurements is just not going to happen without a lift jig.

Suggestions from the experienced are sought..


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## macardoso (Dec 6, 2021)

What about a pair of chain hoists on the ceiling? One lifts it from a cart, then hook it to a second one over the lathe? Tighten up on the one over the lathe as you ease off on the one over the cart. You eventually have your straightede over the lathe suspended. 

If you took a bit of time I bet you could add an eyebolt and some counterweights at each end so the straightedge is balanced about the eyebolt. That would make it relatively easy to align it with the ways as you lower it down. 

Just one thought.


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## Downunder Bob (Dec 6, 2021)

You could try suspending it from your hoist on some stout bungy cords, or springs such that it has an effective weight at the job face of maybe only 1Kg. It would then be easy to manouvre it around without popping any safety valves.


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## woodchucker (Dec 6, 2021)

I vote for a gambrel  type  (block and tackle) setup . And if you look around you can also find easy locking setups so you can one hand lock the rope, then unlock it.
but the rope setup with pulleys, is far more easy to control.. and no chains to damage your  straight edge.  
if you think about it, the engine hoist is a perfect place to mount it, but probably not high enough. you could build an insert into the end to raise it for this task.  something in a sought of Z shape. but the long leg not leaning but perpendicular to the short legs.


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## jmkasunich (Dec 6, 2021)

Couple of sturdy pulleys attached to ceiling joists.  Rope from straightedge up to first pulley, over to second pulley, down to counterweight that is roughly the same weight as the straightedge...


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## rabler (Dec 6, 2021)

Limited space may make it impractical, but if I planned to do a lot of printing with it, I'd want rig on overhead bar with a counterweight.  That way you could still manually manipulate the straight edge, but maybe at a 10-20 lb net positive weight.  Then you'd have no need to mess with a pulley while trying to also align/print.

Take about a 5 foot bar, suspend it by a rope/chain at the midpoint, drop a line from one end to the straight edge, and hang counterweight off the other.   It should pivot enough to give you some range of motion, so you can print and then move it back to a resting position completely by hand.


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## C-Bag (Dec 6, 2021)

Hopefully Richard King will be along because there has to be some kind of acceptable rigging for this. I’ve seen huge camelbacks on eBay and the guy who sold me my Biax had a 6’ one. So even though us hobby guys don’t often do it I know the guys who did this for a living back in the day did it all the time.


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## graham-xrf (Dec 6, 2021)

Thank you all for the suggestions. I think I try something that combines these practical ideas.

From @jmkasunich and @macardoso, I will try and exploit the joists. Over my little shop, where the granite will eventually live, I did make them strong enough to be floor joists, and they are on 400mm centres, and I can use a cross-beam to share load.

From @woodchucker, the suggestion for fine control from block-and-tackle I do like. The manual block and tackles, with chains, are gorgeously slow, and can't run back from being self-driven, and the rope-only version seems more appropriate. Chains slinging about around such surfaces is not a good idea. I will prefer something that is inherently safe if one "lets go".

@Downunder Bob  Bungees is so very Oz! It sounds as if it could be useful, but perhaps set to -1Kg instead of +1Kg, so that it does not have to be "held down".

@rabler : Making the whole thing neutral by counterweight, yet able to move it about, is the best thing. Up or down, it stays put. Even though my outside shp, when I move stuff into it, could one day have a couple of steels along it's sides, and a 3.6m RSJ little gantry crane thing, setting up in one corner from joists with a counterweight jig looks to be on.

You guys are the best!


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## jwmay (Dec 6, 2021)

Spring balancer mounted to an arm with two joints. Although, you've got plans now, so maybe nevermind. Lol


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## graham-xrf (Dec 6, 2021)

C-Bag said:


> Hopefully Richard King will be along because there has to be some kind of acceptable rigging for this. I’ve seen huge camelbacks on eBay and the guy who sold me my Biax had a 6’ one. So even though us hobby guys don’t often do it I know the guys who did this for a living back in the day did it all the time.


Funny you should say that!  There is a huge pile of good scraping info on the "other" site, among it the sentiment that scraping is now the more and more a skill kept alive by "hobbyists". The pro's just junk the amortized machine, and look forward to the new latest and greatest. There are good folk there too, but sadly, it did not take long to come across unpleasantness.


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## graham-xrf (Dec 6, 2021)

jwmay said:


> Spring balancer mounted to an arm with two joints. Although, you've got plans now, so maybe nevermind. Lol


OK, would that be where a spring takes up the role of counterbalance?
There is, of course, the need to be able to balance it along it,s length so it sits level. The gadget used under car engine joists can adjust to move the suspend point so it ends up over the centre of gravity.


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## C-Bag (Dec 6, 2021)

graham-xrf said:


> Funny you should say that!  There is a huge pile of good scraping info on the "other" site, among it the sentiment that scraping is now the more and more a skill kept alive by "hobbyists". The pro's just junk the amortized machine, and look forward to the new latest and greatest. There are good folk there too, but sadly, it did not take long to come across unpleasantness.


Indeed. And that's why I view it like a shark tank, cool to look at but I don't want to stick my hand in there. If you want to get bit just say the distasteful words "hobbyist" or "import" and observe, like blood in the water. Increasingly my impression what passes for a machinist is more like a CNC machine tender than an actual machinist of old. So not only are "hobbyists" keeping scraping alive, they are keeping the skills and knowledge of manual machining alive.

 I recently saw a vid on YT that was saying restaurant workers were getting paid more than machinists...it's why the Luddites movement happened. When the weaving machines started into the mills the employers didn't want to pay the craftsmen what they had to pay them before because the machines were doing the work. They were only tending the machines. I guess I'd be grumpy too


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## jwmay (Dec 6, 2021)

graham-xrf said:


> OK, would that be where a spring takes up the role of counterbalance?
> There is, of course, the need to be able to balance it along it,s length so it sits level. The gadget used under car engine joists can adjust to move the suspend point so it ends up over the centre of gravity.









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I'm thinking like this. Forgive the artistry "skills". You could mount it on an overhead trolley as well for greater positioning freedom.


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## C-Bag (Dec 6, 2021)

jwmay said:


> Tool Balancers, Load Balancers and Spring Balancers
> 
> 
> Balance constant loads with our selection of tool balancers, load balancers, and springs balancers from Endo and Hubbel-Gleason! Browse our full collection at Ergonomic Partners.
> ...


Wow, I didn’t know they made them so strong! I was given one that used to be used for air tools on a bench. It is incredible for balancing my angle grinder for doing detail work. Back when I was fabricating for a living I could hold up my 4 1/2” Makita grinder all day. Now I’m not doing it all the time it no fun. But the balancer is a beauty. I made a small jib crane for my welding table and that’s where the balancer lives. It also doubles as the overhead hanger for my Foredom.

 Once you get a balancer set up you’ll wonder how you ever did without it.


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## graham-xrf (Dec 6, 2021)

jwmay said:


> Tool Balancers, Load Balancers and Spring Balancers
> 
> 
> Balance constant loads with our selection of tool balancers, load balancers, and springs balancers from Endo and Hubbel-Gleason! Browse our full collection at Ergonomic Partners.
> ...


OK - so using one of these spring balancers instead of a counterweight effectively halves the load on the overhead support. That's good! 

If what it holds up is the centre of the @rabler style (say wooden) beam, and the two short straps going to the straight edge hang from that, set apart by approximately the Bessel distance, it can still be moved about at will.

The straight edge tool can be raised or lowered at as needed, and when let go, it stays put, as if gravity is cancelled.
Length-ways, it can be tilted either end up, though when actually working, it would be horizontal.
It can be rocked on it's axis, but again, normally sat with measure face downward.

I do like this!   There remains the little plan to have end support rests to set it down on between spotting, or hold it somehow, turned over, the better to be cleaning off, wiping, and laying on blue ink with the brayer roller. I am not sure one wants to be inking it from underneath - upside down.
Thanks very much for the suggestion!


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## woodchucker (Dec 6, 2021)

C-Bag said:


> Indeed. And that's why I view it like a shark tank, cool to look at but I don't want to stick my hand in there. If you want to get bit just say the distasteful words "hobbyist" or "import" and observe, like blood in the water. Increasingly my impression what passes for a machinist is more like a CNC machine tender than an actual machinist of old. So not only are "hobbyists" keeping scraping alive, they are keeping the skills and knowledge of manual machining alive.
> 
> I recently saw a vid on YT that was saying restaurant workers were getting paid more than machinists...it's why the Luddites movement happened. When the weaving machines started into the mills the employers didn't want to pay the craftsmen what they had to pay them before because the machines were doing the work. They were only tending the machines. I guess I'd be grumpy too


some of those guys are truly gifted as well at CNC. They are dealing with real machinist issues as well.  Just different.


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## matthewsx (Dec 6, 2021)

Load leveler and an extra pair of hands with your engine hoist?









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John


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## Janderso (Dec 6, 2021)

graham-xrf said:


> Funny you should say that!  There is a huge pile of good scraping info on the "other" site, among it the sentiment that scraping is now the more and more a skill kept alive by "hobbyists". The pro's just junk the amortized machine, and look forward to the new latest and greatest. There are good folk there too, but sadly, it did not take long to come across unpleasantness.


The unpleasantness seems to be a pattern in the every day discussions.
It’s unfortunate as there are plenty of seasoned pros on the site.


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## graham-xrf (Dec 6, 2021)

Janderso said:


> The unpleasantness seems to be a pattern in the every day discussions.
> It’s unfortunate as there are plenty of seasoned pros on the site.


I am happy to read away through their (quite extensive) threads of good information that have built up, but I don't post to the site. I have noticed there is now some push-back from their professional members who are starting to take the troll types to task. There is increasingly less tolerance of opinionated nastiness. That's good! Even so, I can tire of having to skip past such exchanges to get back onto the real thread - if it ever does get back.

This HM site is the place where I know I won't get any unmannerly responses, even if I do something really stupid, or have to ask about stuff starting from a position of complete ignorance. The worst that can happen is some comedy. Also, over time, one can get to know other members to the point I am pretty sure that if you put a whole bunch of them into a room with refreshments, all that would happen is a party with animated discussion of things machine-related.


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## Janderso (Dec 6, 2021)

One more reason to thank our forum moderators.
They give us a long leash.
I feel a well deserved tug from time to time
Thanks fellas!


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## C-Bag (Dec 6, 2021)

matthewsx said:


> Load leveler and an extra pair of hands with your engine hoist?
> 
> 
> 
> ...


My only problem with that setup is that the work and the controls. Many a time using an engine hoist I wished for another person running the hoist while I lined stuff up. It’s why I kinda like chain hoists better for delicate work. I do think the leveler is a good idea. Used them many times.


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## tq60 (Dec 6, 2021)

We have klien block and tackle rope sets.

Small blocks about 2 inch diameter pulleys and they have a finger that sticks out to forum a sharp v where the pull rope enters.

You pull t the side as you let the rope I. And it wedges in the vault and stops.

Used to to swap out the 120 pound batteries in the forklift.

Real easy to control with one hand while other operates the rope.

Sent from my SM-G781V using Tapatalk


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## vtcnc (Dec 6, 2021)

tq60 said:


> We have klien block and tackle rope sets.
> 
> Small blocks about 2 inch diameter pulleys and they have a finger that sticks out to forum a sharp v where the pull rope enters.
> 
> ...



What is it called exactly? Klien?? Do you have a link or photo? Sounds like a useful setup tool in general.


Sent from my iPhone using Tapatalk


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## Dabbler (Dec 7, 2021)

I'd love to see a picture of that arrangement to change batteries also!


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## tq60 (Dec 7, 2021)

Did not take photos of battery swap, batteries are cell site batteries, 22 long 4 x 12 standing on ends, used top cage on lift to hoist the batteries into the home made battery box.

Can get photo later, I think it may be a lineman winch or something to that effect.


Go to Amazon and search for "klien block and tackle", the klien one is about 120 bucks and others 25 or so.

Got ours from estate sales, one came complete with the bag. 

Ours is the 268 model.

Look for the little finger on the top block, that is the important part that makes it work so well.

The cheap ones do not have this requiring a helper or tie off, certainly not one hand use.

Sent from my SM-G781V using Tapatalk


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## graham-xrf (Dec 7, 2021)

C-Bag said:


> Wow, I didn’t know they made them so strong! I was given one that used to be used for air tools on a bench. It is incredible for balancing my angle grinder for doing detail work. Back when I was fabricating for a living I could hold up my 4 1/2” Makita grinder all day. Now I’m not doing it all the time it no fun. But the balancer is a beauty. I made a small jib crane for my welding table and that’s where the balancer lives. It also doubles as the overhead hanger for my Foredom.
> 
> Once you get a balancer set up you’ll wonder how you ever did without it.


Looking about on Amazon, etc, one of those goodies capable of hanging 40Kg cost £1300+
That would be more than the cost of the lathe and straightedge put together!
I may go with the counterweight! 

Thinking harder, the counterweight only has to work a small height range. The pivot point could be near one end of the counterweight arm, as a lever, where (say) a 10Kg weight on a spacing of (say) x4 compared to the x1 on the other end where the heavy tool is hung. The up/down adjustment is very fine, and the total in the main sling is 50Kg, instead of 80Kg.
(I know, I know - we need a sketch! )


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## vtcnc (Dec 7, 2021)

graham-xrf said:


> Looking about on Amazon, etc, one of those goodies capable of hanging 40Kg cost £1300+
> That would be more than the cost of the lathe and straightedge put together!
> I may go with the counterweight!











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## Dabbler (Dec 7, 2021)

Klein makes about 5 models, but the 268 you are referring to is just one component, the block.  Even for the best fit for your description, I cannot imagine how you rigged it.  I'd have to see a photo to understand who you are using it.  

-- I used to be a technical rope rescue instructor, so I understand pulley systems quite well (as well as my engineering and rigging background). 

All this to say that you have come up with something really special!  I would love to see how you rigged it, even with a dummy load!


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## graham-xrf (Dec 7, 2021)

vtcnc said:


> Gleason Reel Constant Pull Tool Balancer, 4"W x 2-7/8"D, 5 Lb Capacity, Black
> 
> 
> Gleason Reel Constant Pull Tool Balancer, 4"W x 2-7/8"D, 5 Lb Capacity, Black. Usually ships in3 days. Buy it and Save at GlobalIndustrial.com
> ...


Almost a toy compared to the need. The tool weighs about 40Kg (88Lb)
[Edit: Ahh - I get it. Maybe you were replying to Dabbler ]


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## vtcnc (Dec 7, 2021)

graham-xrf said:


> Almost a toy compared to the need. The tool weighs about 40Kg (88Lb)


Ah! OK. Yes, it will lift dust cover off your tool with little effort!


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## rabler (Dec 7, 2021)

Well let's see,
use an overhead piece of unistrut spanning a couple rafters,
get a unistrut trolley: https://www.amazon.com/Genuine-Unistrut-P2950-EG-Trolley-Assembly/dp/B00KN9UA0S
hang a block and tackle from the trolley to a balance beam.
Use the 4:1 balance beam so your total load is ~50kg.
That would give you a broad range of movement, and fine control over a small range for actually printing.


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## graham-xrf (Dec 7, 2021)

rabler said:


> Well let's see,
> use an overhead piece of unistrut spanning a couple rafters,
> get a unistrut trolley: https://www.amazon.com/Genuine-Unistrut-P2950-EG-Trolley-Assembly/dp/B00KN9UA0S
> hang a block and tackle from the trolley to a balance beam.
> ...


Yes indeed - that is pretty much what I was describing in post #26.

My little shop is 3.65m (12ft) wide across the inside, with over-designed joists. I made them floor joists instead of ceiling joists (so I could stack stuff up there). A more general mini-gantry hoist has been suggested, hanging small RSJs each side along the walls, and a somewhat fatter moving RSJ across, riding on bearing runner plates. These beam trolly things can be bought, but are often made as a DIY project.

Not that I am contemplating anything as mighty as as the project by April Wilkerson, but it does illustrate the principle. Just imagine it scaled down to a single fixed Unistrut hung across a few (say 4) of the oversized ceiling joists. Their trolly plate is seen at *6:06* in the video. There are plenty other videos about beam trolley hoists projects.

Unlike a full moving cross-beam (gantry?), designed to access the whole shop area, the much more modest arrangement is to use a single short beam hung on the joists, long enough to get over the work area, starting from one end over the floor. One dimensional trolly movement along the fixed beam is what you have. The beam does not have to be stout enough to free span across the shop. It just gets fixed at 4 points 40cm apart.

RSJ beams are more to handle bigger loads, like a 1/2 ton and up. In my case, a Unistrut is cheap, fast, and perfectly good for a little 50-80Kg load. I think I will try the scaled-down Unistrut version first. It may be all I ever need. As it happens, I already have some Unitstrut and hanger brackets stashed in the garage. I would not be using chains.

DIY Garage Gantry with Chain Hoist


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## C-Bag (Dec 7, 2021)

graham-xrf said:


> Yes indeed - that is pretty much what I was describing in post #26.
> 
> My little shop is 3.65m (12ft) wide across the inside, with over-designed joists. I made them floor joists instead of ceiling joists (so I could stack stuff up there). A more general mini-gantry hoist has been suggested, hanging small RSJs each side along the walls, and a somewhat fatter moving RSJ across, riding on bearing runner plates. These beam trolly things can be bought, but are often made as a DIY project.
> 
> ...


I know one of the guys here made a unistrut overhead and found the spec's somewhere as to what it would support. it was surprising.

Does your plate have end holes for bolts to rotate it on axis? The more I think of this the more it seems like doing surgery with hammer. 
​


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## graham-xrf (Dec 7, 2021)

C-Bag said:


> I know one of the guys here made a unistrut overhead and found the spec's somewhere as to what it would support. it was surprising.
> 
> Does your plate have end holes for bolts to rotate it on axis? The more I think of this the more it seems like doing surgery with hammer.
> ​


A rotation extra degree of freedom is, of course, good to have. This time the (steel) cable everything is hanging on, will just let the load rotate a little.
It's length is clamped to be fixed, and the only up/down is from the 4:1 lever that @rabler and I have been discussing.

Sure, I know that a little ways down the line, I might well hanker for the utility of a pulley-block, or little winch thing, to have more coarse range up and down, but we are making this stuff up as we go, including perhaps some schemes that turn out to be a bit of a regretful bust.

Your phrase "surgery with hammer" is right on, and it goes to the dilemma in very title of this thread.
The stuff is big and clunky, (big hammer territory), yet needs to be smoothly set exactly in position, moved about in a very controlled way, and lifted off carefully so as not to smear the print. We need uncompromising high force, manipulated over small distances with good control, which is why I find the 4:1 final lever attractive. We can't have stick-friction jerks, inertia wobbles, sudden stop bounce, or other bungee-like situations. I even think that a solid rod, or piece of all-screw with end nut adjusters, in place of a flexible bouncy steel winch cable, may be a smarter choice.
(That's another notion that also might have as yet unseen downsides!   )


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## rabler (Dec 7, 2021)

I think what C-Bag was asking was if the cast iron straight edge had bolt holes on the ends, so that the line along the long axis through the bolts passed through the straight edge center of gravity.  That way if you lifted it from those bolts, you could rotate the flat face of the straight edge up to ink, then rotate again to print.  Admittedly that is not hoisting by the Bessel points.


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## graham-xrf (Dec 7, 2021)

rabler said:


> I think what C-Bag was asking was if the cast iron straight edge had bolt holes on the ends, so that the line along the long axis through the bolts passed through the straight edge center of gravity.  That way if you lifted it from those bolts, you could rotate the flat face of the straight edge up to ink, then rotate again to print.  Admittedly that is not hoisting by the Bessel points.


My apologies for not originally mentioning the other thread that motivates my quest for a good way to work a heavy straight-edge.
You get pictures of the thing here --> *My 48" Straight Edge*

It does have holes all the way along it to tie into, but I was thinking just to bolt-clamp onto the 1/2" thick "tabs" that have the 3-point hardened balls set into them. The ties would go straight up onto one of those adjustable arms used with car engine hoists to get the suspend over the centre of gravity, though maybe with some alternative to the big chains, which might cause damage.

But - you are both right! The need to spin it over on it's axis to ink it is a prime requirement. Hmm..

[Edit: Maybe fix it to a plank at it's Bessel points, and give the plank jig end cheeks with a rotation bolt in each, and hook onto those? ]
[Edit2: Maybe even can do without the leveler]


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## C-Bag (Dec 7, 2021)

rabler said:


> I think what C-Bag was asking was if the cast iron straight edge had bolt holes on the ends, so that the line along the long axis through the bolts passed through the straight edge center of gravity.  That way if you lifted it from those bolts, you could rotate the flat face of the straight edge up to ink, then rotate again to print.  Admittedly that is not hoisting by the Bessel points.


I’ve seen some Russian straight edges with those bolts and with cast in knobs for rotating on axis. That 48” long I beam casting is pretty stout. I wonder if there is any measurable sag if supported by the ends? I don’t see any way to easily rotate SE if supported by 3 or 4 points. Talk about moving the mountain to the mountain.


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## graham-xrf (Dec 7, 2021)

C-Bag said:


> I’ve seen some Russian straight edges with those bolts and with cast in knobs for rotating on axis. That 48” long I beam casting is pretty stout. I wonder if there is any measurable sag if supported by the ends? I don’t see any way to easily rotate SE if supported by 3 or 4 points. Talk about moving the mountain to the mountain.


The edit on my previous post about using a plank with cheeks around it would, I think to allow the roll-over rotation, while only attaching at it's designed support feet.

It is very strong. You won't budge it when set on a bench, but it's self-weight is it's own enemy, Here we are not talking about just getting to hoist something heavy. We also want that it does not deflect even a tenth or two!

Unfortunately, without a big granite,  I won't be able to measure the deflection if it were suspended by it's ends, but here, we might be able to compute our way to knowing that. The FreeCAD software on my computer seems able to do that. I only tried a simple cantilever beam tutorial example, but it seemed easy enough.


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## homebrewed (Dec 8, 2021)

I think a support system with fixed-dimension components, whether they be cables or ropes, won't do what you want -- you need to move the straight edge back and forth to make a print.  Fixed supports will require the supported object to rise and fall as it moves about, not conducive to making a good print.  A counterbalance scheme to offset the major part of the weight in a Z-axis-insensitive-manner seems more appropriate to me.  With a good enough counterbalancing setup you should be able to do things like the center of rotation test.  So sez he, who has done nothing like this!


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## graham-xrf (Dec 8, 2021)

homebrewed said:


> I think a support system with fixed-dimension components, whether they be cables or ropes, won't do what you want -- you need to move the straight edge back and forth to make a print.  Fixed supports will require the supported object to rise and fall as it moves about, not conducive to making a good print.  A counterbalance scheme to offset the major part of the weight in a Z-axis-insensitive-manner seems more appropriate to me.  With a good enough counterbalancing setup you should be able to do things like the center of rotation test.  So sez he, who has done nothing like this!


Hi Mark 
Yes, in the way my.. ( revise that to "our" ) minds work, I have been playing out in my mind possible scenes of how the other experts might have have been doing it for decades. The whole deal swings on a support that is a radius away, which would lift it away if we move anything sideways. This time, we have the scheme to be able to move it to take the print, because of the 4:1 lever.

Start with the top support at the Unistrut. Once approximately overhead, we will not be expecting the rollers to move about any more, but it can if it has to. The cable goes to the lever piece of wood, 20% from one end, and a lump weight on the other end so we have a 4:1 counterweight, which balances the load down to something short of about a kilogram or so, the very last being taken in a little cord going to a cleat on the bench. This cord is by-passed by a slightly longer, fixed safety cord which sets the low limit - to prevent slip-ups. It allows the adjust cord to be (slowly) let go.

Taking a print movement can be by small movements which only cause rotation on the suspend cable. The end of the 4:1 lever would be relaxed enough so that there is some weight on the print, but perhaps not the whole load, when the cord is put into the cleat.

The final suspend is to the mid point of something like a 2x4 long enough to get to the ends of the axis gimbal. It sounds complicated, and I am going to have to attempt a sketch. I am tempted to leave out the final gimbal, and just tie on to the holes near the Bessel points. After a print, lift up a bit, and move it onto supports, like a weightlifter does. Then turn it over and ink as needed. I am likely to seek the simplest, least hassle way that still works. The practical value of trying some of this out is huge, but I am glad we have a plan that makes sense, and has anticipated dangers.

Me too - has done nothing like this!  The contrast between one corner with a soldering iron and binocular PCB viewer, and over at the other end, a 40Kg lump of precision steel with a lathe bed, is striking!


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## macardoso (Dec 8, 2021)

If you haven't read it yet, there are some great examples of exactly what you want to do in Foundations of Mechanical Accuracy. Screen shotted a few for fun reference. Great book BTW.


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## rabler (Dec 8, 2021)

I'm following along with interest, in part because I have a 5' cast straight edge, and good sized surface grinder that I'll eventually want to true up.  My new shop will include a 1 ton bridge crane and 12' ceiling, so the overhead structure will be there, but the challenges of dealing with a heavy straight edge still requires something similar to what you're contemplating.  

I do have a 3' x 4' granite plate.  I plan to have a 10' x 12' office/metrology room with better temperature stability to keep it in, but that will have a 8' ceiling, so printing large things on the granite plate also has some constraints.  Quite likely a unistrut solution will be used there.

I appreciate the aversion to chains, as they can both damage things and just get to be clumsy.  

I'm not sure where my electronics bench is going to end up, similar equipment


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## tq60 (Dec 8, 2021)

Dabbler said:


> Klein makes about 5 models, but the 268 you are referring to is just one component, the block. Even for the best fit for your description, I cannot imagine how you rigged it. I'd have to see a photo to understand who you are using it.
> 
> -- I used to be a technical rope rescue instructor, so I understand pulley systems quite well (as well as my engineering and rigging background).
> 
> All this to say that you have come up with something really special! I would love to see how you rigged it, even with a dummy load!


First off, forklift battery maybe wrong term.

Batteries FOR the forklift better.

The original battery was toast, sold it to some poor scrap guy from out of town, dropped in his 1 /2 ton Chevy with all the rest of his stuff and the bumper about hit the ground.

We made a battery box same size to hold what we can find.

Still have contacts with cell site vendors and got some 170 Amp hr batteries, these weigh in at 120 or so pounds.

4 inches wide, 22 long and 13 tall.

VRLA and can stand on end so strap around the battery and the block and racke anchored to the cage over the top a d it is up and in.

They fit perfectly with about 1 inch clearance front back and 6 units wide about 7 inches. 

Sent from my SM-G781V using Tapatalk


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## graham-xrf (Dec 8, 2021)

macardoso said:


> If you haven't read it yet, there are some great examples of exactly what you want to do in Foundations of Mechanical Accuracy. Screen shotted a few for fun reference. Great book BTW.
> 
> View attachment 387804
> 
> ...


Thanks so much for the pictures. "Foundations of Mechanical Accuracy" is one I do have. Like Connelly, it's not one that most folk would read from end to end. We choose the bits we need instead.

The images depict their solutions for a variety of situations, likely found more or less in the same way we have been discussing here. As always, we figure out ways to solutions as we go along, while having dipped into the past to get ideas, and avoid repeating mistakes.
Some of those tools in the pictures are truly mighty!

In my case, the need is to discover the truth of, and help fix up as needed, the ways of 36" lathe beds, with the future possibility of a 48".
It seems that to lift the bed takes near the same or less effort than to lift the straight edge tool. This inevitably leads to the (comedy) thought that I could consider just leaving the straight edge set down on it's three support points, and dangle the lathe bed instead.
So is that a truly dumb notion? (It's OK to laugh ROTFL)!  I know that only in this forum could I ask such a question!

@rabler : I have been considering getting a granite 48" on the long dimension, much like yours, though possibly only 30" wide. I would ask how much you love the thing? How useful is it to you? Aside from the very reasonable deal I got on the straight edge, part of my reasoning was the straight edge would do what I needed, and I would only need a bigger granite if ever I I was trying to work on the SE itself.

*Re: The 12 x 10 measure room.*
8' ceiling is high enough for near everything, provided your hoist can get over most of what you want, which probably includes parts of the floor adjacent the granite. If the joists over it go across the 10' span, and you use (say) 2' centres, then Unistrut(s) hanging off them, fixed along the 12' length right near the walls the whole length, lets you trolley a small RSJ, a bit less than 10' long, that would span the whole room. The load, plus the self-weight of the beam, is shared between _two_ Unistruts, anchored right near the walls, the Unistruts themselves supported every 2'. I think the load limit would be what it takes to un-bend Unistrut rolled over edges. In any event, something like this gives the ability to haul up the load, and move sideways to over the granite, and back, possibly to set down onto a DIY floor trolley.
A thing like a surface grinder bed, or any other part with ways, is going to need the ability to be moved sideways.

The size of the RSJ going across the room depends on the weight of what you might hang in the middle, but being only 10' or so long, I am thinking you could use a relatively small section RSJ, say 3" x 4", or use double-depth Unistrut, or some other thing you might weld together.
You might have to get up to some creative projects to end up with a trolley & hoist system that is economical on the high-value height clear between the granite and the beam. In extremes, you might "shorten the legs of the granite stand", but we hope it never comes to that!


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## rabler (Dec 8, 2021)

graham-xrf said:


> @rabler : I have been considering getting a granite 48" on the long dimension, much like yours, though possibly only 30" wide. I would ask how much you love the thing? How useful is it to you. Aside from the very reasonable deal I got on the straight edge, part of my reasoning was the straight edge would do what I needed, and I would only need a bigger granite if ever I I was trying to work on the SE itself.
> 
> *Re: The 12 x 10 measure room....*



I haven't really had the chance to use the 3'x4' plate.  The construction crew is suppose to frame up the new shop next month (January).  As you know there is a lot of work that goes into a new building.  I've been trenching water, power, internet, gas.  Arranging for the electrical upgrade (200A to 400A service).  Once the shell of the building is built, I'll need to frame out the measure room, insulate and wire the whole building, put in a ceiling, build the cranes, etc.  I'm probably at least a year out from being functional in the new shop.

I do like rebuilding machines for my own use.  So issues like this are highly relevant to how I lay out my shop.  I may actually go with a small bridge crane in the office.   Anything that is big enough to justify using a 3'x4' surface plate is probably bigger than I want to lift repeatedly.   And if I do it I'll want at least 1000lbs/ ~450Kg capacity.  A 10' span is small enough it wouldn't need a large I-beam (U.S. terminology, RSJ appears to be the UK equivalent), probably a W6x9.  

I'll need to get the 3'x4' plate calibrated before I really trust it.  I got it recently from an auction, $180 including loading in my truck.  I also have a ridiculously large 50x86 granite plate that was a CMM table.  That won't go in the temperature controlled room, too big.

I know it's a ridiculous amount of equipment for a hobbyist.  Circumstances meant we spent less than half of what we planned on a retirement home, so this is where the extra money is going, along with some simple remodeling projcets.  Large agricultural property with no zoning restrictions like you've had to comply with.


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## rabler (Dec 8, 2021)

graham-xrf said:


> You might have to get up to some creative projects to end up with a trolley & hoist system that is economical on the high-value height clear between the granite and the beam. In extremes, you might "shorten the legs of the granite stand", but we hope it never comes to that!


I'm leaning toward top running bridge cranes to make the most of the height.


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## graham-xrf (Dec 8, 2021)

@rabler
In UK - we also call it I-beam when it has that cross-section.
RSJ => "Rolled Steel Joist", a more general term for most sections. To some extent, we are into culture terminology.
If the I-Beam is horizontal, it's a "joist", and if you stand it vertical, it becomes a "stantion".  

$180 bucks, for a 3'x4' granite, I think, is an outrageous steal! We reserve judgement until you find out if it's any good, and if it turns out to be so, the HM guys will probably have some suitable expressions for you and the deal!

Re: Temperature controlled
Of course granite has a temperature coefficient of expansion, but I don't think it's surface changes significantly from flatness, so long as the granite temperature has permeated somewhat to be about the same deep enough, if not all the way through.  Putting a (thick) insulated lid cover over, and adding removable insulation side panels around, or use a insulation blanket, could preserve retained heat overnight, when heating isn't on.

Perhaps put a permanent fitted insulation board on the underside. It could well speed up the settle next day.

If it has to do a spell of work requiring what amounts to a temperature controlled environment, and you make the boundaries of that environment an insulated box, a low power little thermostat controlled heater underneath for overnight, may be all you need.


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## homebrewed (Dec 8, 2021)

If using a heater you probably want to avoid hot/cold regions on your surface plate.  Things like electric blankets have heater strips in them, not a uniform heat source.  The resultant thermal gradients will cause height variations.  So I don't think this is an approach that will work in a Just Get'er Dun sort of way.

If the surface plate is inside a well-insulated box most of the time it should equilibriate on its own and therefore stay as flat as possible.  And keep the electric bill in check


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## rabler (Dec 8, 2021)

I plan on eventually have a separate mini-split for that room.  The plan would be to set the temperature for something reasonable for about 24 hours before any really precision measurements.  I'd like to get the plate re-certified to class A, IIRC it was last certified to that in 2016.  It'll definitely be a well insulated room, and inside the general building which I'll keep some minimal climate control.  I'm going to be spending a lot on insulation for the whole project.

If I'm remembering correctly from the civil engineers, here a "beam" implies horizontal and a "column" is vertical.

Hopefully I haven't completely derailed your thread.


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