Sunday, December 20, 2009
Oh and I was able to pull out the key holding in the pinion for the main gear that I talked about in the last posting. Seems every time I even think about leaving something and then get at it I discover more. This time it was that the key was not the right width, but was too high and had been filed to a taper - and then was driven in only one third of the way! Good thing I got it out, now I have a new propper size gib key on order.
Tuesday, December 8, 2009
Sunday, December 6, 2009
Sunday, November 29, 2009
Saturday, November 28, 2009
Monday, November 23, 2009
Wednesday, November 18, 2009
The gap looked huge, but on the lathe with a dial indicator it "only" measured 0.020". In any case, to get a decent cut and a feed rate without chatter resulted in 0.030" being taken off the ink surface. A big deal was to have secondary support at the ratchet ring to the lathe chuck. Before that the cutting tool action on the disk was just screeming with vibration. The surface is not perfect, but it is perfectly flat and I can polish the rest in position on the press. Now I've got to get myself a machinist straight edge so that I can measure if the disk sits too low, and if I have to make up a bronze washer for the bearing to bring it up the 0.030" that it was sitting higher before.
Thursday, November 12, 2009
And if that is not enough, the first piece has been painted. I took off the ink platter, cleaned it and painted the under side.
The top side will take some more work. When the press was shut down and stored something was left on the platter - it was likely ink - and that has eaten into the surface. The Scotch-Brite pad on the die grinder is cleaning it up but there are quite a few pits left. So I took the sanding disk and tried to get more agressive in polishing the marks out. I'm not happy with the results. I'm going to look for a machine shop to grind the surface on a lathe so as not to remove too much metal. But its a start!
I found a machine shop, but that started some real concern: We put a straight edge across the ink surface and discovered either the platter is seriously distorted - or it is supposed to be crowned (the center being sone 3/16" higher than the sides). I will have to wait until it is put on the lathe before we can be sure. In the meantime I'd appreciate if anybody can check their C&P ink platters to see it they are crowned or really flat?
Saturday, November 7, 2009
What I really went there fore is a machinists straight edge, so that I could check the bed and platten for straightness. They did not have those in stock and I got talking with a real helpful guy behind the counter and I came away with this real fine tool. Now I'll have to rent a better air compressor for a few days.
Sunday, November 1, 2009
But then some sort of a guilt mechanism clicked in place and I removed the spring attachment to the handle, and then the handle hinge bolt. Sure enough the spring jumped around just to prove me right. After cleaning up the spring though, here is what it looked like:
I'm sure glad I took it apart, it's worn almost half through! When that spring lets go the chase is loose in the press - that would make a mess! There is a lesson in that.
Sunday, October 18, 2009
Length 31", 190 turns of 0.079" diameter spring material, wound to 0.465" inside diameter (0.620" outside diameter).
The longer spring is for the single saddle post & rod:
Length 34", 196 turns of 0.070" diameter spring material, wound to 0.467 inside diameter (0.608" outside diameter).
To be able to get the spring off the rod you need to be able to compress the spring a bit while removing the cotter pin at the end. I found a pice of 1/2" PEX pipe (for residential water pipe use) handy as it has just the right inside diameter and enough wall thickness to push in the spring. Once you get the pin out and release the pressure on the spring be ready to have the spring jump right into your face. A set of leather work gloves on your hands go a long ways to contain the spring force, letting it go more slowly.
Notice that on one end the springs have a little straight tail, that is the end near the saddle post (keeps the spring from yurning).
It'll be fun getting the springs back on...
Saturday, October 17, 2009
Made a decision on the oil holes today. While I have things appart anyway I will redrill the top part of the oil holes and get oil hole covers to try to keep these locations from accumulating dirt, and make them more obvious for long term maintenance.
Sunday, October 4, 2009
I am going to aim for half of that, 1000 iph. My press has a 24" diameter drive pulley. The smallest I am likely to get for the motor side pulley is 2" diameter. So that works out to a 12 to 1 speed ratio.
Here is a picture of the press as it arrived, with all the ties and chains removed, free at last.
With 7 turns per impression on my press, that is 7000 rotations per hour, or 116.7RPM. On the motor side that is 116.7 times 12 = 1400RPM. For an 1800RMP motor, operating at 1400/1800 = 78% speed of maximum is not that bad, but there is something else I have not mentioned before. I would like to increase the time available for the paper removal and placing task (while the platen is open) by manipulating (reducing) the drive speed depending on the press position (when the platen is open). During the three truns of the drive wheel while the platen is open I'd like to reduce the drive speed to about 40% (for a 1800RPM motor that would be 720 RPM). And during the four turns while the platen is closing/opening I'd like to run it at full speed. My press was equipped with a 1800RPM 1/2 HP motor, I have the original motor but not the motor pulley. My plan right now is to use an inverter duty 3/4 HP motor and VFD to be able to handle the cyclic acceleration/deceleration.
An 1800RPM motor actually runs at about 1750RPM at full load. Assuming that it will take half a turn (on the press) to accelerate from 720RPM to 1750RPM, and half a trun to decelerate back to 720, that makes one turn at an average speed of (720 + 1750) / 2 = 1235RPM.
So here is what my prediction is for overall rate:
3.5 turns at 1750RPM (at the press that is like running at 1250iph)
2.5 turns at 720RPM (at the press that is like running at 514iph)
1 turn at 1235RPM (at the press that is like running at 882iph)
Working out the average speed for the time weighting that each speed applies:
(3.5/7) * 1250 + (2.5/7) * 514 + (1/7) * 882 = 934.6 iph average speed, pretty close to the 1000 iph I was aiming at, and I gain a safety advantage with long platen opeing time. Let's see what that would actually work out to: 720RPM / 12 is 60RPM at the press, that is 1 rotation per seconds, so for the 2.5 turns the platen is open - that makes it 2.5 seconds. Plus the bit of time the drive is speeding up and slowing down. So maybe close to three seconds time for the paper shuffle. That seems lots. We'll see! One other feature I have been thinking about is to have two buttons on the feed table that have to be depressed before the press will return into the high-speed mode (or possibly if they are not pressed bring the press to an emergency stop via dynamic breaking). If anyone can think of holes in this reasoning, I'm open for suggestions.
Saturday, October 3, 2009
Here is my friend Tom at the top of Rogers Pass, with the press in tow.
Then a slight, could have been bad mishap. I had attached the thow-off leaver linkage and left the lever pushed forward. Then I worked on cleaning rust off the platen and the tympan bale areas. I left the top bale folded down while I got busy with something else. As I turned the flywheel cleaning the main rocker shaft I felt a bit of resistance on the flywheel. Hm that's not right. As it turns out there id just the right amount of extra space left in the throw-off position so that the bale just gets squeezed a bit - without damage.
Note to self:
1. Never leave anything on the platen that could cause damage.
2. Always turn over the press for a full cycle by hand, and check if anything seems to take too much force!
3. Never leave the platen bales open!
Friday, October 2, 2009
When I first laid eyes on the press I was looking for evidence of oil remaining at the journals ind linkages. There was a lot of oxidized oil heavily caked with dust and dirt in those places, a good sign. When I removed the retaining bolts for one of the connecting rods, sliding the rod off a bit, the journal area was still shiny with good oil. I filled every one of the oil holes and proceeded to move the flywheel back and forth just a few inches. Hearing no noise, and feeling no resistance, I increased the rocking motion untill I finally made a whole turn. Seeing the oil in the oilholes sink down a bit gave me the assurance I was looking for: The oil was flooding the journals. The press moves with absolutely no noise, smooth as silk! The only thing you hear is the little clack of the ink disk advancing ratchet action.
I had to buy a 5 gallon pail of the oil and if it works out as I'm thinking now, I will package the rest of the oil in half liter bottles and make it available for anyone who would like to try it. But I have to try the motor test run first.
The drive wheel is 24" in diameter. Next I want to work out what speed motor I should get. The original motor is a 1926 half horsepower motor that looks like the size of a three to four HP motor today would. I will not be using it since I will want to go with variable speed drive and that requires the use of an inverter duty motor. Those have a lot better insulation than a standard motor and vastly better than what was done even just twenty years ago - never mind eighty years ago.
Thursday, October 1, 2009
I've read about a shop that undertook a press recovery of a press very similar to my moder, also a C&P 12x18". You can read about it here. They really did some detective work on the surface treatment and paint. Their final result looks like a piece of art. My primary motivation is to make the press productive, create art with it - but not make it into a work of art. My paint job will be more utilitarian, but with some appropriate highlights. We'll see if I can do justice to it before I say too much.
Tuesday, September 29, 2009
just outside the garage.
There was this little incident with a blown trailer tire, and that is a great reminder for all who might be tempted to do the same thing: Whatever you do, get a two axle trailer. The friendly U-Haul staff was trying to get us to accept a single axle trailer, when the one I had reserved the week before was not returned in time. Take my word for it, go two axle!
And there she sat in a high speed curve on the Coquihala Highway:
The emergency service arranged by U-Haul was great. Hope Towing rules!
It took me three hours to get her off the trailer, man is she heavy!
And now there are a lot more decisions to be made.
The press had been in storage for 39 years and while there is a fair bit of surface rust, the important rotating surfaces, bearing areas and joints all had lubricating oil remaining (even though quite oxidized and sticky with dust and dirt). So the first task is to take apart all the bearings, remove the connecting rods and evaluate wear, clean lubricate and re-assemble.
I'm getting the idea that it might be worth while to measure and document all the components while I have things appart as well. I have not been able to find a schematic of the machine assembly yet, so maybe I could make a contribution toward that.
Tonight I removed the ink fountain, I will prepare it for long term storage as I will not likely use it for my rather short run work. And I removed the ink rollers and scraped the ink disk. Looks like the press was stored with some ink left on the disk. There is discolouration where the surface deposits were. I applied some penetrating oil and we'll see in a few days if I can emery cloth polish the surface defects out. It looks like the ink disk sits in position just by it's own weight. I wonder if people remove the disk off of the press to clean the ink - rather than cleaning it in position. That might be less messy. We'll see how heavy the disk is, and if it is reasonable to lift it out. After dinner I worked for 2.5 hours applying penetrating oil to bearing areas and looking over the press.
Friday, September 18, 2009
More after the visit to the trailer place...
Sunday, August 30, 2009
Really there are not too many days left, and the press is coming!
Thursday, August 27, 2009
Wednesday, August 26, 2009
I had been making enquiries about the suitability of the press that I was looking for and was told that I really should be looking for a larger press. Due to the rather large solid colour impressions required for my artwork the press needs to be of a larger size. One person said I should really look for a Vandercook. I tried, but could not get close to any in a month of trying. And then the cost...
I can hardly wait to get my hands on the machine.
Thursday, August 20, 2009
Then I discovered a method by which I could be more productive. Scanning my pencil sketch into a computer I can redraw the image using software tools, and then apply colours at my hearts content until I get it right. So originally I used that process to make a printout, that I could then use as a guide for my painting.
Then, via an interesting detour that I will have to write up some time, I came to printing my art with a fine art printer. Now I could sell my work in a much more affordable manner.
But this has left me in a real art no-mans land. I can't get my work into any shows or galleries because they insist that they will not accept "reproductions". I guess it will be some time before competition administrators and galleries will come to accept original digital art. Some actually think the computer does all the work (by computer magic), but most seem to like the final result. People who like it, like my digital originals a lot - and it's for those folks that I do it, providing the best quality of materials and production.
I took time during our holiday this year (due to the less than optimum weather), to do some soul searching and research into what I can do to make my work and the process of producing it come into better alignment. What was the problem you say? Well, I always feel that I have to explain the process and why I am using the fine art printer. Even though, and maybe even because, I do all my printing myself (not that I'm a control freak you know).
A chance encounter with one of the Glenbow museum archivists pointed me in a new direction here. Amazing what happens when you shut up and listen. Took me a while to get what she was talking about though. But after a detour looking into wood block printing, etchings and pochoir, I came across letterpress printing. What a realization! The solid black lines that I have in my work are exquisitly suited to letterpress. It gives an almost embossed quality to the work printed onto heavy paper. And then the machinery. The old cast iron presses that are used to produce letterpress printing are just up my alley. A lifetime spent designing and fixing machinery now comes in handy. What a match, to bring my art and the production of it into such alignment, and then to be able to make the end result even more affordable! I am real exited to make it happen.
Wednesday, August 12, 2009
Since then I've actively searched for another press, but so far have come up empty.
Sunday, August 9, 2009
Saturday, August 8, 2009
I am going to recover it in the next two weeks. Then I will start to remove the rust and first evaluate the shafts, threads and bearings to see if there is enough to work with, to make it work again. Part of me wants to say "no thanks - too much work", and part of me is a sucker for the challenge...