I am finding the process of building this jig fascinating.

 

This isn't much but I did get the little piece of plastic glued together and have it clamped up for a while to see how the joint works. I might leave it overnight before I unclamp it.

I put masking tape along both sides of the glue joint so as to keep the ABS glue off of the exposed parts of the tube so that I don't have to apologize later about the messy look the new tubes have if I don't.

I have pretty well decided that I can do the clamping of the material for tubing to form these intake tubes with using some flat bar material rather than trying to glue them around some other kind of tube. That will let me form the joint flat and then it will take its own circular shape when it is released.That is going to be much simpler, but I am going to have to work up the material to do it with. I think I will make the top clamping member into a hinged component so that it wont be such a monkey drill trying to get the second piece clamped down. I'll just fold it over on the lapped material and clamp it down. There is a little more engineering going into this setup than I want to describe here, but maybe I'll tell more about it as I go.

I also redressed by turning, the reverse megaphone section of the tube form so that it is a little more nearly true and then put its heated coat of epoxy on it to cure overnight. I think all I have left to do to the form is to take it out of the lathe and take it apart then fix the chipped lout areas. Then I'll have to reassemble it and put it back in the lathe and re-turn that section, if I can get it correctly lined up and centered to do it.

 

I woke up thinking about this this moning, so I got up and took the spring clamps off to see what I have. Here are the pictures. It appears that I don't have quite enough overlap of the bevel in the joint so the springiness of the plastic is formig a sort of point at the seam, but not so much on one side as the other. I think that is simply because of the slight difference in the overlap.

I'll be more careful in laying up the actual tubes in the future to be sure that I have complete overlap of the bevels and the joints should come out pretty smooth. Even the way this one is, however, I think the joint is strong and would withstand forming just fine. And, I think the lack of overlap would not even be noticable in the finished product.

At least I think I have found that making the joint with flat bar material is going to work just fine. I'm going to buy some of that today and start working up the clamping jigs for these.

 

I studied the joint in this sample section of tube I made and have decided that the most likely reason the joint is making itself sort of pointy is that the glue has softened the plastic in just the area of the joint. This is rather than the joint having too little overlap. I miked the bevel and found that the thin side of my bevel is .012 inches thick and the material is only .040, so there is still plenty of "meat" in the joint. I think I will also add a tiny bit to the overlap in any case.

What I think I am going to do is leave the joints clamped together for much longer than overnight; in fact I think I will leave them clamped up until I need to put them on the form for forming. That way the solvent (MEK) in the glue will have much longer to disipate. Then when I take one out of its clamps to form I can just put another one in and put it at the tail end of the line to get formed. Since there is going to be very few S3ers in need of these, that should give plenty of time to have a good strong and aged joint.

I bought 10 sets of material today to work up into the clamping jigs for these tube joints. I think I have enough small C clamps to do the job, but if not I can make another run to HF for some more. I will pobably spend most of this next weekend working up these clamping jigs, and probably only after I finish up the heater mounting points in the mill.

 

Today starts another weekend of work on this project. During the week I was able to order and pick up some material I need for the oven and for the jigs to help form the basic ABS tubing for these intake tubes. Here are a couple of pictures of some of the material--the rest in still in the back of the GT (which now has a flat tire on the rear).

Now, with this, and when I finish up the heater mounting points, and maybe do some repair work on the fins of the form, I will need to drill 500 to 600 holes and countersink many of them for these next two phases of the project.

 

Whew! That sure took longer that I had expected. But then, it always does. I did get the heater element mounting points finally finished. I got the broken drill bit out of one hole by back drilling it and then driving the bit bit out backwards with a small drift punch. Then I discover that I had a broken piece of bit in another hole that I had not been able to drill. I couldn't figure out why there was a hard spot in that hole, but when I back drilled it I hit the same spot and then I used a small carbide mill cutter and milled down to it and then into it a little when I then drove it out with the drift punch. That's when I discovered it was a piece of drill bit that I didn't know I had broken off in there.

Then I tapped the bottom part of these holes and redrilled the upper part to the major bolt size then counterbored each of them for the socket head and then fit the bolts I'll use to clamp these points onto the heater elements. Then, for S&G,I docked the foreward corners so they will look more finished.

I put two clamping bolts across the open ends of the points, when one each might have done the trick, but I didn't want to end up with anything like TBF.

Here also is a couple of pictures of the material I had cut and bent to make the oven. I have them simply standing here in their approximate configuration, at least most of them, so you can see what I am doing. I'll put these together with rivets, so I have to drill about 10 or 12 holes along each joint. Since there are 12 joints there will be 24 rows of rivet holes, so I have a lot of holes to drill and deburr just in these 8 pieces of aluminum. Then, when I have them all pretty well fit together with clecos I'll start the assembly with the mounting points and whatever I come up with for wiring and such. Then I'll make the final assembly with mostly aviation hard rivets, at least on the inside, and will probalby use pop rivets on the outside since those locations will be difficult to buck.

I'll end up with the oven having walls that are 2 inches thick which I'll insulate so I don't get burned using it. I'll also have all or most of the wiring inside the walls and will use high temp wires, which is $4 per foot, unless I can find some cheaper that is heavy enough.

The oven is 16 inches across inside and I think that is going to be just about the right size for more even heat without hot spots and still not be so large as to be in the way too much. The four heat elements will be hung in the corners and that is kind of why I have formed them at an angle.

 

I have maybe half of the holes drilled and about a third of those deburred. I made a drill jig so that I didn't have to mark every hole to drill it. That worked pretty well. I have the basic part of the oven temporarily assembled with clecos ready now to locate the heater mounting points and do some wiring and then start riveting it together. I figured out that I can shoot the rivets in the inner part and about half of those in the outer part since I can rivet them together seperately. Than I 'll be able to slip the outer over the inner and line it up and pop rivet the two together.

Then I layed out the quarter inch bar stock that I am going to use to make the tubing clamping devises with. I am using the same drill jig for the three-inch spacing for the piano hinge that will hold the two clamping bars together and that works well again. After I get all of those holes drilled I'll have to put the bars in my roll and put some curvature in them. I am going to curve the base or mandrel piece one way and the two clamping bars the other. That way I will get some clamping force in the middle of the tube joint since there is no other way that I can think of the clamp the joint all the way through its length.

After I get these holes drilled I need to counter sink all of them so I can use flush rivets to attach the hinges. At least that will save me deburring one side of these holes, although this bar stock in 6061 and much harder so it doesn't burr up very much at all.

I was originally thinking that I would be putting this oven up on some kind of stand, but after I got the material and can see just how tall 34 inches is I realize that in order to work with this thing I wont need it up so much. So, I'll probably put in on a stand, but not very tall.

 

I went back and looked at the basic checklist I put in post 82 and see that since the few numbered items are pretty broad, even though I think I have made pretty good progress at this point, I cannot actually check off any more of the items.

I will note that the heat elements actually came from New Jersey or somewhere in the East, and not from China. I'm not sure where I got the idea they were going to come from China, but they didn't.

I find myself being somewhat reluctant to take the form out of the lathe and take it apart, but I guess tonight I'll do it and see about the repair work it needs. Although I will have to get used to the idea that I will need to be able to reassemble the form each time I make a new Intake Tube, and I think I will be able to, I think my ability to put it back into the lathe so it will turn true is going to be limited.

As to the Oven, I need to find some kind of insulated gromets for the wires to go through the inner wall of the oven and then connect to the heat elements. I think I have found some hi temp wire on eBay and will order that for a lot less than $4 a foot. I also need some gromets for the wires to go through more of the sheet metal between the oven walls, and it needs to be something that will be resistant to heat. I don't know yet what that is going to be.

Then I need to get a two-pole single throw switch for the oven. I'll work on that later today if I get done at the office early enough. I'll need a 240 volt 50 amp male plug and some three or four conductor flexible wire, but I may have the wire already.

 

I took the form out of my lathe and took it mostly apart and then cleaned up the mating surfaces and put some tape on the surfaces where I need to do the repairs. Then I mixed up some epoxy and tried to fill in the voids where chips had departed. Then I found that in the largest voids the glue was simply running out, so I put some saw dust in the glue and pushed it back where it needs to be. I hope the sawdust will help keep it from running.

After the epoxy sets I'll use my dremel and roughly trim the repairs then try to hand file and sand them to near finish. Then I hope to be able to put the form back togbether and do some final finishing in the lathe.

Then I had to take a little time and put a new motor in my belt sander. I had finally gotten tired of having it slow down to nearly stopping when I try to sand anything very large or with much pressure. I changed from a half horse motor to a horse and a half. I was just going to go to a one horse, but my one horse motor runs only at half the rpm of the half horse one I took out. Then I find that the switch doesn't work now; so I guess I'll have to go out to sears and see if I can get another one.

Then I worked on the top and bottom of the oven. I had obtained some aluminum for that this week and so I cut the corners off and formed the folded edges and with the scraps from the corners I made some angle pieces to rivet into the flat corners of the oven. I'm taking a break right now, but in a bit I'll go out and check on the epoxy and then start drilling some more holes in the oven and see how far I can get with finishing it up. I'll need to make some kind of stand for it, and if I can find some box tubing I think I'll use that. I only need to get it about 6 or 8 inches off the floor, so it ain't going to take much.

I have ordered the hi-temp wire, but is isn't here yet so I wont get that far with it until later. I am going to try to mount the heat elements though since I have all of that part of it worked up.

 

I cut a large hole in the top of the oven in my mill using the rotary table. I love working with the rotary table. Then I have the top and bottom drilled and partly located on the body of the oven. I am going to fasten the top and bottom with screws rather that rivets so I can take the oven apart partly if and when I might need to repair it such as replace one of the heating elements.

I also found some 3/4 inch box tubing that I think will be enough to make the stand. It is not going to be very fancy, but will be enough to raise the oven about 6 inches to a workable height.

The epoxy is starting to set up on the form segments so I pushed it around a bit to be sure there is enough in the voids so I wont have to do it again. I probably will have to anyway. I may also find some tiny voids in what I have otherwise finished, so I might have to take it apart again for one more session of repairs.

 

I know this project seems to be taking longer that one might like, but that is just the nature of it when so many aspects of it have to be developed, and when one has other things that are also important to do.

Today I took the masking tape off of the form segments and then put it back together and put it in the lathe to begin dressing the epoxy. That worked pretty well except I find that either some more chips have jumped out or I didn't get them all filled the first time. This time I took the form partly apart again and then put it back together with wax paper in between in the area I am working and then put it in the lathe and filled the voids with epoxy there. I am letting that cure and then tomorrow I'll be able to try again to dress it out hopefully to near final finish. If that works then I'll coat that segment of the form with epoxy and heat it in then lightly sand the whole thing out and call it finished.

Actually before I can call it finished I will have to drill a multitude of tiny holes all over it for the air to be drawn out with the application of the vacuum.

Then I put some more time into the oven. I drilled the bottom and then fit all of the 8 corner pieces. Then I made the simple base and bolted it on. Then I set it up and removed the interior so I can start to make a final assembly of it all. I'll be mounting the heat elements next on the inside and then rivet it together and have it ready for wiring. Then I'll mount the switch on the outside so that I'll have it all ready for the hi-temp wire when it gets here. I'll also start riveting the outside together, but first I'll have to locate my rivet gun which I think is out in my hangar.

 

i really want to clean your shop floor for some reason... its all but compelling me too! :-P fantastic lathe work.

 

When you work on creative projects you make a mess.

When you stop working on the project to clean up the mess, you put things away.

When you put things away you quit thinking about them.

When you quit thinking about them you direct your attention to something else creative.

When you think about something else creative you stop working on the project you should be working on.

Don't stop working on the project you should be working on to clean-up.

Wait for someone like Ducman82 to come do the clean-up for you.

 

I'm sure we could get a gathering together at your shop one day and everyone could help clean it for you haha.

 

I am getting pretty good at working the form over to correct defects that appear in it. I centered it in the lathe again and first applied some heat to the epoxy to temper it a bit. That seems to harden it much better than it gets on its own even over night. Then when I file and turn on it it comes off as powder rather than as some softer goo.

I fixed the center accordian section again and find that there are still two or three defects, so I put some more epoxy in them and will let it cure again. While I am waiting I applied small bits of epoxy to some of the very minor defects in the other accordian sections and will let that cure and then dress them out tomorrow or later.

Then I turned my attention to the oven again. I didn't get much done, but I did hang the heat elements and mounted the on/off switch. I also found a chunk of three conductor wire that I can use as the basic power cord for the oven. I'll need to go the the HW store and get a male plug for the end of it.

I was going to do some riveting of the inside and the outside, but I can't find my rivet gun. I will either have to go out to the hangar and locate it or I may just go to pop rivets for the whole thing instead. Even then I couldn't find even one of my several rivet pullers. I suppose they are out at the hangar also.

Then I had to devote some time to my equipment which needs a little maintenance. I got part of that done and am now taking a break.