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If you did not notice already, there has not been much action here for quite some time.
I have moved my blogging to http://artletterpress.wordpress.com - there are a number of reasons for this. And I have regretted it several times over, but there it is...

New Resolve

Talking over the paint disaster with everyone I come in contact with who even might have the faintest interest or knowledge in the subject, I have come to this: I will rent a high pressure/hot water washer and use a hand sprayer with gasoline and caustic soda to soften the paint. That's it so far. I have no idea what or even if I'm going to paint the press.
But here some pictures of the last improvement:

The lock roller rotating on the fixed stud, following the shape in the small head lock cam was quite worn. More than twenty thousands out of round it was likely forgetful lubrication that was to blame since the roller is a bit hidden under the delivery board. The local machine shop did a nice job of cleaning up the stud on the lathe and pressing in a bronze sleeve into the roller. I ended up drilling the lube hole myself as the machinist forgot about it. The roller and lock action is very precise now.

You can see the surfaces with dissolved paint after the gasoline cleanup. One of the mechanics I spoke to suggested a vegetable based spray which leaves a film of wax that will prevent rusting. I'm looking to get a can of that to try out.

Paint Disaster

I did a bunch of looking at the paint options before committing to the Tremclad paint, but it is obvious to me now: I did not do enough! The paint is trouble, I can't believe people have used it to paint cars? Last weekend I was moving over to the front of the press. I had stripped off the main gear cover and the throw-off lever and linkage, and painted those black. Now I changed to the dark blue again for the frame and just above the main shaft in front.
There was some old greasy dirt there and I dipped a rag in gasoline to clean the crevices and general area. Vigorously rubbing and pulling the rag through some tight spots, gasoline dripped down over some of the previously painted area. I could not believe my eyes, the paint (more than a month old) wrinkled and bubbled and could be just wiped off! What a mess, now what? I am sure glad I did not paint the press for looks! Having to be that careful not to get any solvent on the frame, when cleaning up the press after every job, is just not going to happen.
I'm having to get used to the idea to remove the paint and start over...

Here is a picture I just found from the day  after I got the press home. Good the neighbor had a strong tree there to anchor the come-along.

Reinstalling the Pinion Gib Key

After quite some time now, and a wrong size key purchase, I went to work yesterday to fit the new gibkey. First was the requirement to shorten the key by 3/8" as I did not want it sticking out too far from the pinion, when in position.

Next came filing the bottom side down so that the leading height was just under 5/16" so that the key would fit into the opening. Once I had the right entry height, I discovered the key needed to be filed a little thinner too, so that it would fit into the keyway. During that exercise I discovered that the keyway in the shaft was marked up quite a bit from someone bashing on the previously installed key. So there was some filing and cleaning up of the keyway grove on the shaft in order.

Here is the completed key:

I reduced the taper in the key thickness to less than 1/32" of an inch so that there would be good holding power and more of a spread of the torsional forces along the width of the pinion/shaft keying.

Before removing the old key I tied up the press with my 5 lbs sledge between platen and bed, and marked the gear engagement so that I would not loose mechanical timing when the key was out.

Here you can see how the pinion keyway was distorted by forces on the old key, which was only partially inserted (about 3/4" into the keyway only).


And here it is driven in quite solid, in all it's properly aligned glory:

I'm sure glad I went through this trouble, as the pinion would have come loose, likely at some inopportune time. As well, the gear teeth were just starting to mark up, with the pinion pushed too far over, and with the smaller meshing there was obviously higher load (and wear on the teeth) taking place.

Delays

It's been more than a month since my last post. Not that I have been lazy about this, but the money making work comes first, and so the work increments on the press have been smaller and with several week interruptions. Then there was the gib-key fiasco for the pinion gear that I ordered wrong, and had to re-order. Then there was the straight edge that I ordered - and that somewhere during shipment punched a hole through the packaging and escaped into the wild (likely in the back of a UPS truck). That too had to be re-ordered, but now I got it and can finally get to work checking the press bed for straightness.
The last week has been like Christmas. I got packages from the seller of the press, with the feed table (with the cast bracket) and the all important chase. Then I received the mini-furniture cabinet that I bought via briarpress from a printer in Florida, with a bunch of metal furniture (still waiting on the wood furniture). Ah, and I got an impression counter, not really needed, but why not.
And then there was a two week holiday in the sun and several weeks away up north.
A new resolution to throw out more stuff from the garage, so that I can fit the new stuff in place and make more room for working the press.

A list of what is required to complete the reworking of the press and make it ready to print:

• Finish cleaning and painting
• Polish / straighten press bed
• Check & correct siderail elevation to press bed
• Check & correct/adjust platen to pressbed distance
• Define motor size and purchase
• Buy and install VFD
• Buy ink rollers & trucks
• Buy first zinc plate with backing
• Buy tympan & pressboard
• Buy cotton paper
• Buy ink

Well that's it for now - pictures to come...

Shaft Treatment

Yes it has been unbearably cold! So I got done litte with working on the cold cast iron. But there are some new pictures of what I have been concentrating on lately: Polishing shafts. Here are the throw off linkage shafts.

And here is the flywheel shaft after the sequenced emery cloth treatment.

And the back shaft with the side arm still to be done.

And this is what the rear of the press looks like right now. On some of the parts I noticed the old ink remaining here and there seeping through the paint. So I will have to go for another coat.

And this has me considering changing the banner picture for my blog!

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.

Gear Misalignment?

Is this a problem I'm asking anyone who has an opinion - don't hold back.

The main gear and the drive pinion are out of alignment by about 1/4 inch (on the left side). By the corrosion on the main shaft it looks like the pinion did at one time sit about 1/4 inch to the left, which would bring all of the gear-teeth surfaces into full contact. Is that something I should correct? Looks to me like the pinion is shrunk onto the shaft as I don't see any pin or screw holding it.

Main Gear Camwheel Cleanup

I just about overdosed on gasoline vapours. Right now it is -22 degrees F out there, and it is fairly cool in the garage. I removed the right side arm and the large gear cover, and proceded to clean off the grease and junk off the main gear and it's pinion.

That took a lot of gasoline and a lot of rubbing with a terry-cloth rag. But the gear and the pinion are nice and clean now. And then I looked over every tooth, and aside for a little piece of metal that was embedded in the root between a couple of the large gear teeth, everything looks good. The pinion is not aligned very well with the main gear (it's out be about 1/4 inch), and I am wondering if the pinion is deliberately moved towards the press frame to keep the shaft positioned in place. But there is hardly any wear on the gears.

Grippers and Gripper Bar

Last night I thought I'd attack the gripper bars and the rail they mount on to. Turns out the bars are kind of bent and not even. One has definite signs of type embedding into it. And there are a lot of hammer marks from bashing the bottom of the grippers when they were being adjusted.

So I filed the edges for a better appearance. I noticed all the gripper pieces were originally painted black. Because the grippers will have to be moved back and forth for various size work, I don't think the regular paint is a good idea. So I am either going to try a thinner epoxy finish or maybe leave them unpainted. Here the gripper bars are at the first stage of cleaning with a die grinder attack. Next I have to rig up some anvil surface to hammer them straight, and then do the final polish.

Back Shaft Polishing

After most of the week away I decided to spend some time on the back shaft (the one connecting the press bed and the roller frame, and onto which the side arms connect). Now that the items around it have been painted it really looks bad.

The shaft rotates only within the limits of the throw-off linkage, so it's mainly stationary, and dirt and stuff built up over the years allowing some serious corrosion to happen on the upper surface of that shaft. Scotch-Brite, air tool and emery cloth were applied vigorously and I worked up a sweat. Tomorrow after some final polish I will apply some clear coat to the shaft. I decided to try out this product I found, to highlight a few of the machined areas of the press. As mentioned before, I am not going to apply pinstriping and a work of art paint-job. But the machine does not have to look boring either. I am aiming for a "serious machine" look.

More Cleaning & Painting

I took off the ink plate support braket, cleaned and painted it. The disk advance leaver as well got the same treatment. As I was working on that I realized that it is easier to shim the whole braket up (to make up for the ink disk machining hight loss), then to make a bronze disk to put on the disk journal. Then I takled the rear of the press bed (under the ink disk), with those deep pockets formed by the web of reinforcing bars. That area is a real trap for dirt and junk and is also the place where I have found the worst scaling (likey from the original casting process).

After yet another night of cleaning and painting the rear and sides of the press bed are painted. For a while now I thought the paint I'm using (Tremclad dark blue) was too soft. But I'm changing my mind on that. The first items I painted more than a week ago now are getting harder every day. I was worried about being able to wipe oil of the surface if it stayed relatively soft. And I'm getting used to the colour as well - I thought that it was too light, but it's nice to be able to see all the parts even when the light is not right on it, and also I'm just getting used to it.

A New Surface on the Ink Disk

Tonight the ink disk got machined. There was significant run-out, although not as bad as it looked when we put the straight edge across it. There is something about the light coming through that little gap formed by the straight edge and the surface being checked that really amplifies any error.

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.

Finally Moved Inside

After a bunch more moving stuff around, throwing stuff away and recycling - the press is inside! Its mot pretty, and there is a lot more stuff that will have to go, but it's inside before the snow!


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?

A Better Tool

What a difference a better tool makes! I visited a machinist tool shop and came a way with an air operated die grinder, a disk mandrel and a selection of sanding and cleaning disks. The tool runs at 20,000 RPM and does a real nice job of cutting through surface rust. So far I have only used the polishing disks, I really don't want to take off metal unless I can measure the results.

Now I just have to deal with the fact that my air compressor is waayy too small to power the tool properly. Right now I have to wait 30 seconds, make a pass, wait another 30 seconds and so on.
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.

When do you stop?

It has been cold, and the progress of getting the place for the press clean is slow. But there was a good day a few days ago and as I looked over the back side of the press I felt that some good cleaning would be all thats required. After all, what could be wrong with the simple spring with the attachment to the chase clamp and handle? And with all that grease and dirt on it, it would just jump like crazy when I got it off - and who knows what a pain it would be to get the spring back on after.
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.

Anybody Need a Motor?

The motor that came with my press:

It's for sale!
Offers?

Saddle Post Spring Detail

Turns out there are two different springs. one. the shorter one for the double saddle post & rod:
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...

More Rust, Dust & Gunk Removal

For a few days It's been very cold. Since the press is still out in the driveway I haven't got much done. Today was a good day. Worked most of the day on the press, removed the saddle stud & rods and the gripper bar. Noticed a difference between the double saddle stud and sthe single one. The double saddle stud springs are shorter than the single saddle springs. I wonder if that is because the single saddles were not used on the press (by the previous owner), thus never got compressed or cycled? Or is there a technical reason for it? Tomorrow I will measure and document the springs. Made good use of degreaser and cleaners today. The platten cleaned up real nice with the rust remover.

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.

Interesting Encounter, Speed Calcs

Had an interesting encounter today at the farmers market. When I was looking to sit down to enjoy my danish and espresso, there was no table free. So I shared a table with an older couple. We got to talking about things and surprize surprize the gentlemen used to feed a C&P letterpress many years ago in a little town west of Red Deer. I asked about the speed and he insited that they were doing about a hundered pieces a minute top speed. Hm, that seems a lot. The other production number I have heard a few times is about 2000 impressions per hour (iph).

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.

Some Days are Easier than Others

Today was another day of rust removal. Now my order at Acklands came in and I have better emery-cloth and some rust remover to try out. Had bought a new set of wrenches at Home Depot, an open end - close end ratchet combination set in the typical heavy plastic packaging that you need a set of shears to open. When I came to use the 9/16" wrench I find the ratchet did not work, and looking at it closer it was a used wrench of a sightly different style (still a Husky). Back to Home Depot for a refund, but that was not so easy. Even though the packaging claims lifetime warranty there was a lot of waffling going on, I felt they were of the opinion that they were letting me get away with something. Frustrating.

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!