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3/25 Update

Busy few days. Workin hard and playing harder.

In the past couple of days, I made a ton of progress.

I fixed the 2 bushing holes that I messed up, one from a bad freeze-fit, and one from a stupid measurement error. The solution was to weld up the hole and re-bore it. A very time consuming fix. Don’t make that mistake!

I also had to torch away parts of the lower arm to get proper clearance for the cylinder and linkage.

The cylinder space wasn’t accurate because I couldn’t find the spec’s for the cylinders overall diameter, so I assumed it would be 5.5″. Turned out it was 6″. Not a big deal to fix- Just had to torch away the excess. I found where to torch by making an aluminum “mock-up” of the cylinder and using that to guide where to torch.

Torching 3″ is very difficult. Unlike 2″, it requires you to pre-heat the metal from the bottom, or the oxy will have a really hard time making a straight cut. I made the mistake of not pre-heating when I torched the holes in the linkage, and that’s why they came out so badly.

Once I torched away the cylinder space, I could weld the cylinder mount. Should’ve taken video of the process, but it was pretty simple. Basically, I flipped the arm vertically, so the attachment wouldn’t fall, and held it perfectly centered using magnets. After I tacked it, I double checked it’s squareness, and gave a solid 1/4″ fillet all the way around. After that, I ground away any weld material that would block the cylinder. See the photo in the gallery below.

For some reason, the lower arm was interfering with the linkage. I’m still not sure why the linkage space wasn’t right. In the design, I left 1/4″ clearance for it, because I knew there would likely be small measurement errors, and that the lower-arm torching wouldn’t be perfectly accurate. I need to go back and double check all my measurements on the linkage, and the CAD file I sent for torching the lower arm. It could have been as simple as the fact that the torching is only guaranteed by 1/4″ by the metal supplier.

Either way, I torched away the excess, and now it will work.

I also freeze fit the remaining bushings for the hole’s I’ve bored. I will need to do one more batch of freeze fitting when I’ve completed the upper arm. Here’s a vid explaining the pre-heating; you want to get the steel hot enough so it starts changing colors. Didn’t get any shots of putting the bushing in cause my camera ran out of juice.

The final freeze fit got stuck midway thru. I was going to take it to the press to push it in, but the guys volunteered to help me. My little girl muscles weren’t enough to hammer it further in, but Mike’s most certainly were! That’s one heavy hammer.

After the freeze fits, I had to grind down whatever parts of the bushing were sticking out of the material; some of the material was thinner than specified, so the bushings were sticking out. This could cause a problem because when the pins are in, they will need to be clamping down on the entire piece, not just the bushing. If it’s just clamping on the bushing, the metal could end up slipping out further on the bushing, causing the arms to get out of parallel. This would destroy clearance accuracy with the blades, and result in either sloppier cuts, or broken blades.


3/9 update

Yesterday, I finished up the Main Linkage, and drilled the remaining holes in the Lower angle mount.

The finished Main Linkage (OK I still need to sand and freeze fit, but this only takes a few minutes)

I tried to saw off the extra material on the linkage, but ended up breaking 2 blades attempting to saw the material. I’ve determined I’m not strong enough to properly use it. Jimmy ended up cutting off most of it. I broke the last blade in the middle of a cut, so we had to torch off the remainder. (see video below)

Then I milled the rest of the material so it was 1 1/16″, to fit the cylinder. This took ~4 hours. Unfortunately, I didn’t open up the cylinder until I’d already machined it, and the opening between the ears was actually 1 3/16″, different than what the specs said. This pissed me off because I probably spent an extra hour machining off that material, because the specs lied. This taught me a valuable lesson– check materials which have been received for their specs. Don’t assume they match.

I also drilled and bored the hole for the cylinder mount. See the video below about the difficulties I had mag-drilling the material.

Also, I finally ordered the fastener from Bolt Depot.

On an unrelated note, I just sold a $350 bookshelf, so many of my recent money worries are over! Might take a bit of time away from fabrication, but I can afford gas for another month!! I’d been in a bookshelf slump for all of Februrary, and had only sold $55 worth of merchandise. I have enough saved to last a few more months, but lack of income scares the pants off me. Huge weights have been lifted from my shoulders.

3/8 update

I finished putting the holes in the Lower Flat Mount today, as well as drilled the holes for mounting the blade for the angle blades. See the photos and video below.

I’m going to wait to weld the table and angle support on until I have the machine assembled. I may need to machine away some of the mount to make proper clearance for the blades. Waiting insures machining will be much, much easier. Also, its either machining that, or machining the upper arm more, which is very un-desirable.

I broke the blade trying to cut the linkage today. Purchased more, and will try again today. If I’m successful, I’ll machine the rest of the main linkage and be done with it tomorrow.

I’m also ready to start on the lower arm! I’ll start by mag-drilling the holes for the linkage pin holder, and main pin holder.

Transfer punching the holes for mounting the blade

2/21 Update

This durned finger is taking more and more time away from fabrication. I went to the doctor again this morning because it looked infected and it was. They suggested I take time away from working. I worked the rest of today anyways and it felt fine, but now it hurts worse than ever. I’m only working a half day tomorrow. This needs to heal.

Didn’t get much done today, but I’ve figured out how to solve some of the fabrication issues I was facing.

For cutting the main linkage down, I’m going to use uncle’s portable cold cut saw and saw most of the area away. This would probably also be doable with a vertical bandsaw, but ours isn’t in operation. I’ll machine the rest away after sawing. He volunteered to do it for me, and I’ll probably have him do it, because thats one scary looking saw!

The hole I'll torch tomorrow. Inner circle is what I'm torching, outer is approximately the final diameter after boring. I still need to drill a small hole for the torch to start in.

For making the big holes, I’m going to try torching them. We have a motorized circle cutter that can be used with a torch (video to come). This will torch the holes for me and they will be pretty exact. I had considered it before, but shyed away from torching, because we will need to bore to size, and the torching will harden the steel, making it more difficult to machine and more likely to damage bits. My uncle said I don’t need to worry about that, but I’m still going to do a sample with one of the holes to see.

Another option is renting a slugger bit of 2.75″ diameter for this, but I couldn’t find anywhere that rents these out. I’m calling one more place tommorow that a friend recommended. Buying one would be too expensive (~$500) .This would be much easier than torching, as there’s no cleanup involved, and it won’t harden the steel.

Attempting to drill the big holes

I was originally planning on drilling these holes, and had machined our bit for this. After attempting to drill, it was clear that this was not going to be possible. Even though I’d ground flat spots on the bit for the chuck, the chuck kept opening up and losing grip on the bit. I couldn’t get it tight enough to actually drill much. Also, the lowest setting on our drill press is still much too high for using a bit that size. Torching will be much easier.

The other thing I did was drill the center hole and drill and tap the grease holes on the vertical linkages. This is pretty straightforward and easy, a nice change from the way things have been going.

The vertical linkages

Monday 2/20 Update

Another day of long hours with little results. Started at 7:30, finished at 5:30. I find myself getting very frustrated and stressed. We have such a big shop with so many wonderful and exotic tools, and none of them are properly functioning.

Ok. Enough complaining for the day.

I did finish the pins. It was the same process as the others. Since we didn’t have a 1.5″ drill bit, I had to machine the threaded rod a bit to be able to insert it. I then protected the threads with tape and welded. After that you grind away the weld so it’s flush with the top of the pin. See the video below.

I continued working on the main linkage and drilled the “prehole” for the big bit. I may end up renting a large slug bit instead of drilling.

I did prepare the bit for drilling today. This took a long time to prepare because the large bit wouldn’t fit into the drill press. We had to improvise a way to machine it down to be able to chuck it. See the photos and video below. My granddad torched a slit in some tubing so we could put that around the drill bit to chuck it into the lathe. Unfortunately, the table on the drill press wouldn’t lower enough to put the bit in, for some reason it’s getting stuck. Hopefully I’ll diagnose and fix tomorrow.

I learned today that you can take up to .04″ away with each pass on our lathe! Perhaps this is common knowledge, but years had passed since I’ve had machining practice, and I could’ve sworn you weren’t supposed to take more than .01″. This made machining much faster.

I also learned how to adapt a tap to be used with a drill! Very useful. See video below.

I also received and cut the vertical linkages to size. This was interesting, as before cutting it weighed 170 lb. Nobody was around to help me lift it, so I found a ladder and items of various heights and slowly elevated it to saw height.

One more thing worth noting is that I received the blades today. All have arrived except the lower angle blades.

Reflections week of 2/13

I was not successful on meeting most of my goals for the 2/13 week. I did prepare all the bushings, and take the first steps on many of the other parts.

Many things prohibited me from reaching my goals, but ultimately, had I been more cautious and forward-thinking, I could have gotten most of the goals finished. The main blockers this week were breaking my finger, which slowed me down considerably and took a lot of time and  money in doctors visits; and machine failures.

To spend my time more efficiently, I plan on getting to the shop when they open at 7am instead of doing errands in the morning. I can do errands after 3:30 when we close. I also plan on using evenings to work on the Sketchup and materials ordering, as I’ve ordered very little of the materials.

The drawing for the punch table

Since my last update, little has happened. I lost most of Thursday because I went to the doctor. I prepared the drawings to torch punch table, and Main Pin Holder, and Main Linkage holder. We have a panograph torch which has a camera, and follows a drawn line to duplicate the line on the piece you’re torching. For it to work properly, you need a special kind of ink, which I could only find in a bottle! I had to buy and learn to use a calligraphy pen. It was kind of fun to break out my architectural drawing tools once more! After that I went to the shop to try torching the punch table at the very least, but the camera wouldn’t pick up the line. We couldn’t figure it out on time for me to leave for the doctors, but later that day, Jimmy opened the circuit box and cleaned it out, and it worked the next day. Unfortunately I didn’t

The Panograph

have the special pen to fix some breaks in the line which prevented the camera from following the entire course of the line. More details and video to follow upon using the torch.

This part needs to be machined from 3" thick to 1.0625", but only in this small area.

Friday was a mess of tools not working properly. I began machining the main linkage on our Jig Bore machine. This is something which can be done using a fly cutter on a mill. We began on the Jig Bore, because its bigger and in better condition than the mill, and a bit easier to work on. However, the auto-feed was not working, and nobody could figure out how to fix it. Since we need to machine  a large part away on the main linkage, it is ridiculous to do it by hand. I will need to machine away roughly 62 layers (the machine can take off about 1/32″ at once) to get the part to size each layer took me about 6 minutes. So, to do so manually is a royal waste of time, when with an autofeed, you can do one layer at a time, and walk away in between layers.

Since our mill has an autofeed, I tried fly-cutting on that. It didn’t work well, as the motor is really weak and kept would getting stuck easily. I also tried fixing the mill, but no avail.

My plan is to ask on a few forums and call an old employee to see if I can fix the auto-feed on the Boring machine. If I can’t figure it out within a few weeks, I’ll do it by hand.

Since neither of these were working, I decided to drill the holes in the linkage. However, we had bits for both the mag-drill and drill press which were about 2.25″, and both of them had such big shanks that they wouldn’t fit into their respective machines! I will need to machine down the drill bit so I can fit it in the drill press.  I’ll drill these holes monday.