Greetings all,

I'm looking for something that has proven to last indefinitetly inside a rotary engine. It will need to be built up about 3/8"-1/2" where I'm using it. I was looking at High-temp Lab-Metal, but I'm told it's a real pain to sand. Any suggestions will be greatly appreciated.



Thanks. https://www.nopistons.com/forums/pub...DIR#>/cool.png

anything... jbweld sucks, use a welder.

Devcon Liquid Steel "B", mix the complete contents of both cans and dont worry about the waste

Thanks for the advice guys.https://www.nopistons.com/forums/pub...#>/biggrin.png

I wish I could weld it(havn't completely given up brazing or soldering), but it's in such an awkward place it would take forever and a day to grind and then hand sand it to the desired profile.



I checked out Devcon's site and found Plastic Steel® Liquid (B). Is that what you were refering to banzai?

It looks very promissing, although, the tech sheet for it does say it shouldn't be feathered. What has been your experiance?



I'm still open to more suggestions, so anyone else should feel free to chime in if they feel like it.





Thanks.

What EXACTLY are you trying to do?

Well...

I am going to do something seemingly crazzy/unconventional with it. I'd rather not say exactly because:



1. I'm not prepared to prove what I'm going to try because my knowledge in the matter is very limited. With time, testing, and furthuring in my education, I will hopefully be able to do so then.



2. I'm sure it would be very controversial because it hasn't been tried before(that I know of), and goes against the common-knowledge of the performance oriented world.



3.In the end I might end up with a pile of scrap metal and a great deal of embarrassment from following some crazzy notions.



I'm very sorry if I come off as some kind of my-idea-is-so-special-it-has-to-be-kept-secret jerk. Please don't take it that way. We all have some ideas/projects that we just don't want to share openly for one reason or another.



Basically, what I'll be doing is applying the filler/epoxy to cast iron which has had the casting texture ground smooth. I need to build it up to 1/2", either in layers or all at once, depending on the filler/epoxy used. It will also need to be featherd so as to blend seemlesly. It will be exposed to oven temperatures(450 F) and then slightly above average engine temperatures for the rest of its life. If the filler/epoxy were to ever come loose, the engine would probably be severely damaged or suffer faillure.



I've looked at quite a few types of metal fillers/epoxies that claim to do x, y, and z. But I want something that has been proven in the environment it will be used.https://www.nopistons.com/forums/pub...1047683473.gif

You are such a my-idea-is-so-special-it-has-to-be-kept-secret jerk!









Hey document it with pics and then share it with the class even if it blows up!

Lol.



Don't worry. I am documenting everything, that way, the people who may have to scrape up my remains will have some idea what I was attempting. https://www.nopistons.com/forums/pub...R#>/tongue.png



I do plan on posting when/if i get things back together. Its not going to be anything really outstanding. I'm trying to stay within my miniscule budget, and still be creative with a few things at the same time. I'm really attemping to make it as reliable as possible and more fuel efficient with a slight power gain.



At the moment, all progress has halted because i havn't found a suitable filler...

This forum is much more open minded, you would be surprised the beneficial ideas that get bounced around on something outrageous rather than people shooting the idea down to begin with





We've seen some crazy stuff here, that you wouldn't see posted anywhere else. It's all in the atmosphere. https://www.nopistons.com/forums/pub...IR#>/smile.png

Not only that, but there is also a rather good chance that whatever this brainstorm is has been done before, to whichever degree of success. If so, then one could have less wheel reinventing to do.

Alright, ok, you all win. I'll tell I'll tell! https://www.nopistons.com/forums/pub...1047683329.gif



I am going to use the filler to DECREASE the size of my port runners in such a way to promote more even flow and a better charging effect caused by the INCREASE in velocity. Simple, right?





Now, could you guys with the experience please suggest a suitable filler? The pro's have stuff that is tried and true. What is it?





Thanks.

There's nothing new about that. The key is how much and where you do it. JB Weld, Devcon and other materials can work just fine. If you have it fail, you didn't prep the area good enough. The key is in really good cleaning of the surface that you are applying the epoxy to. You need to also rough up the surface quite a bit. Not only with sandpaper but also cut small grooves into the surface. This will help hold the epoxy on. I've used Devcon for years and never had a single issue.



As far as the smaller are goes, check out mototuneusa. It may be primarily a motorcycle website but the info applies to all engines. http://mototuneusa.com/thanx.htm There are alot of great articles there. Check out #17 for the proper way to prep a surface for epoxy. You'll need to experiment with how to do this on a rotary. You never know what could happen. It might work or it might not.

I know its not something new, although it is quite different from what the majority of porters are doing.

This isn't the only thing happening to my engine.(The other stuff is what really involves the most risk) I just wanted to have a clean thread on the best filler for the rotary. I'm sure most people have realized how much "dead space" there is in the ports. It is really evident when you use some modeling clay and a flow bench...



So, which Devcon do you use, how hard is it to sand, and can it blend/feather well?



Thanks.





Oh yeah, I almost forgot... MotoMan is one cool dude!!!

You need to be careful sanding it as you can easily go too far. Especially with a sanding drum on a Dremel. Use the Dremel to get close and then do it but hand. You can do the final roughing up with the Dremel but be VERY careful and steady or you'll have to go back and add more.



I don't know about type 1 or 2. I do know that my local home improvement store sells 2 kinds. One is a putty stick that you squish together (2 internal putty parts) in your hands and then apply and shape until it hardens. I don't use this stuff. I use the 2 part epoxy that comes in tubes and needs to be mixed like JB Weld. It even looks like JB Weld. I've never had any problems with it.



I do have a flowbench that I built btw! Haven't used it in a while. Need to pull it out again and play around with some different things.

I already posted which DEVCON to use, Liquid Steel 'B'

This is a natural path of development on the intake side. The big problem with going faster is the port opening into the chamber.



The NA rotary has two RPM where it is more than 100% efficient. Or, volumetric efficiency exceeds 100%.



It ingests more than its displacement. Free turbocharging without the turbo.



So it isn't all that bad right out of the box.



I love fooling with this stuff. The fact that its been done is of no value to me. I want to see it on the flow bench.



The ideal runner is a very large diameter round tube. The one that works in a real engine is a quite small diameter round tube.



The higher velocity of the small tube adds inertia to the charge and aids in the over boost.



The two flow problems you see are that a round runner goes to hell in a 90 degree turn. And Bournulli kills off that velocity at the port opening shape that takes advantage of more favourable timing.



The ultimate answer is of course, the Periphery port. Ideal shape. no velocity change at the port face, and so on.....



As runner diameter is reduced, velocity for a fixed depression goes up. Until.....surface...or parasite drag begins upsetting the boundry layer, and drag increases at the square of velocity.



This is seen on both the dyno and the flow bench as sort of a wall where the next change in the same direction, seems to have little affect on the outcome. Total flow or power.



There is improvement to be had at the transition between the runner and the port opening. The "bowl" as it were. The combination of a turn of close to 90 degrees and a velocity drop from the drastically increased diameter (shape of the port opening) is a big problem.



The ideal shape for a turn is the flattened "D" shape. This is with the vertical back of the "D" shape on the inside of the turn. This is done without increasing cross sectional area, so as to maintain velocity.



The port face opening shape in the rotary is dictated by the various tracks of the seals. Not ideal. And the need to adjust closing timing to alter peak torque RPM.



Without redesigning the engine from scratch, there is a lot of room for improvement. The runners are cast as is the bowl shape.



Be sure to have your little weather station going to correct all tests to a standard day.





Lynn E. Hanover

Lynn just for trivia what are the RPMS that a N/A rotary excedes 100% VE?

From what I've been able to find so far, it does seem to be the best epoxy. The only thing that bothers me a little is that its max temp is 120 C = 248 F.

http://www.bsc.com.au/devcon/devcon.pdf





Great stuff Mr. Hanover! I do have a homemade flow bench, and was able to see how the port flow was affected in various areas. I do need to start factoring in the wearther like you said. The barometric pressure is always changing, as well as the ambient temperature.(can't forget altitude either, right?)



Ahg! Now I've got to go dig those equations up...





An S5 exceeds 100% VE when the VDI activates, right?(My best guess is 6000rpm).



What about the other rpm? https://www.nopistons.com/forums/pub...1047683561.gif





Nopistons Rocks!!! Thanks Guys!

no if they only still made BELZONA super-moleculiar

One is real close to peak torque as you would expect, and the other (if I remember correctly) is well below that, so as to be good for economy but useless for racing.



Note that the three runner systems of the new engine is to take full advantage of the two peaks a total of 6 times, to maintain a fairly flat torque output. Very busy, but effective.





Lynn E. Hanover

You need air density, temperature at the air inlet, and barometer all corrected to sea level on a standard day (60 degrees) from SAE tables.



The second most overlooked item is two plane precision levels on the machine, and a system for adjusting for changes. Note that the longer the run of the output momometer (the closer to horizontle) the more sensitive it becomes. Also the more like a level bubble it looks and acts, thus the need for the level check between sessions.



If you use water instead of oil for indicaters check fluid levels before each session to avoid errors.



I added a long run of hose attached to a third monometer at one end and to a length of brake line tubing at the other. Good for probing for high velocity problems and pressure changes inside a port.



If you move too fast the indicater fluid will vanish from time to time, like having a butterfly snap shut, or the like.



If there is interest, I can Gin up some plans for a decent flow bench made from damn near anything at hand.



Newguy, what are you using for the blower?



I have a centrifugal blower from a tank of some kind. Its 24 volts but boy does it move some air.



I only speak 12A with carbs. I don't know what a DVI is ??????





Lynn E. Hanover

Really?

Yep.





A flow bench is can be thought of as three boxes.



The first box has the hole for the test pieces to sit on.



At the rear or bottom (makes no difference) of the first box is a big hole

that leads into the second box. There must be some system to open and

close off this hole with great precision. I used the flycut off-fall of making the hole.

The plug or throttle (sounds better) is mounted in such a way that it can be screwed

back into the hole. I mounted the plug on a long piece of 3/8" threaded rod.

A stiff bracket With a 3/8" nut brazed to it, close to the hole supports the plug

so it hits the center of the hole, when screwed in tight. The other end sticks

through the front of the box, through another 3/8" nut welded to a large washer,

and then into a handle or crank of some design. I used a wheel off of a shopping cart.



The second box has a hole that lines up with the first. The blower must be

installed so that all of the air it can collect must pass through this hole with the throttle.

The output of the blower will be free to escape into the second box. This box need only

be sized to fit the blower.



The blower may be as simple as an old shop vac.



Sitting on this box is the back box. The vertical box that will

support the meters (monometers) and cool stickers your friends put on it.



Pressurized air from the blower box will be free to move through the back box and

out the top of that box through a series of different sized holes. These holes are closed off

in different combinations to adjust the output to make the indicater monometer into the

center of its range. I used a thick board covered with a sheet of foam to just move

along the top of this box to do that job.



You install a tall vertical "U" tube monometer along one side of the back (vertical) box

with one end in the text box and th other end open to the room.



The indicater monometer can be a long glass tube (very cool) or just another length of 1/4"

plastic hose from sears. Sears has all of the flow bench parts. This monometer is installed

at about a 20 degree angle across the top front of the vertical box. One end is inside that box

and the other end open to the room. Some method of holding the tube straight is required.



I cut up some measuring tape refills to use as reference numbers and put them alongside

the monometers.



So air is pushed into the test box through your test piece, when the blower lowers the

relative pressure in the blower box.



You control how much airflow it can get with your throttle wheel or crank.

You clamp your test piece over the hole. You adjust the throttle to get 6" of water on the

vertical monometer. All testing will be at 6" on this piece from then on. The throttle controls only

the test vacuum or depression.



The output of all of this flow is now escaping through the holes at the top of the third box.



Cover a few of the holes at the top of the third box and watch as the latteral monometer begins

to move. It is measuing air pressure in the blower box. It is very sensitive. Go slow. Keep the throttle adjusted to maintain 6" on the front box.



Once things stablize, note that the smallest change to anything in or even near the test piece, makes a big change in the monometer.



Shazam!!!



You have a flow bench at $6,000.00 below retail.



Now let your mind wander around this shape for a few seconds. Does it have to be a box? If I knock off some of the plastic parts from the shop vac blower, could this fit in a grease drum or a nail keg. Could you build this into a work bench and connect the blower box to the vertical box with a 6" flex hose. Just make a cover for the test hole when not in use?



If I had two old shop vacs and inverted the can of one onto the motor section of the other and that would be the top box.. and the test box connected with the flex hose???



Could the throttle be a big gate valve in the flex hose to the test box?



So long as there is a throttle system on the suction side, the whole unmodified shop vac could sit inside a drum of box of some kind, with the back box on top of that?



The answer is yes to all.



Drawings to follow.



Look at Paul Yaws web page for a totally cool home made flow bench. www.yawpower.com





Lynn E. Hanover

Wow! This is really good info! Thank you for spending the time explaining all of this stuff.



My thrown together flow bench is very very basic and runs off of my house-vac https://www.nopistons.com/forums/pub...IR#>/wacko.png, but I was able to get some good comparative values when I did some experimenting with the clay. I plan on making one according to your description when I need real precise readings.



I feel so privileged to have all this input. My punny thread is not worthy of the voluminous amount of info you're giving out. If you do plan on going into greater detail about flow bench construction/testing, I seriously think it would be highly appreciated arciveable meterial in its own thread.

Its just to good to be lost in a thread about epoxy...



Note:

The S5's intake is a variable dynamic intake(VDI) it utilizeses the pulses from the intake closing of one working chamber to charge the other working chamber(and vice versa) via two different length runners. Nice manual illustration/explaination attached.

[attachment=34275:attachment]

the rx8 goes one step better, and that is actually to close off the ports/runners that arent being used. also the 6 ports are gear driven from an electric motor

A Picture is worth a thousand words https://www.nopistons.com/forums/pub...#>/biggrin.png

I have two of the three pictures done and in MSPaint. It is an old version. I bought a used computer that works well after my new computer blew up. Threw a rod. Got oil all over the rug.



I need a modern version of MSPaint, or, some freeware that can save these pictures as JPGs.



Any ideas. Don't go into the weeds too far. I can just barely understand computers. That first one was a Coleman. Powered by white gas. This one is solar powered.



Lynn E. Hanover

My computer is powered by Alvin and The Chipmunks running in an excercise wheel, and is part pocket calculator, yet it runs PhotoFiltre just fine. You can do mild editing, like text insertion and the like, and it can be downloaded for free. I don't remember where I got it from but the usual gang of search engines should pick it up.



Nice thing about junk computers. They're still state of the art relative to when they were new, yet they can be had for free or very close to it. More money to throw at the car!

Indeed it is.



Here is a picture.





Lynn E. Hanover

Here is the second picture.



This is the blower box. It can be a second box or can be produced by extending the front box

and installing a partition. It houses the blower (whatever you will use). The suction side of the blower

must be sealed to the throttle hole by a foam gasket, hose, silicone etc.



The output of the blower is free to escape up through the back box. There can be no air leaks at all.



Install a leveling system for the machine, and two planes of levels affixed to the test piece surface.





Drawings to follow.





Lynn E. Hanover

state of the art in british computing!

great artwork! thanks a lot for the efforts, Lynn!

The back box is the finish of the carpenty and the begining of the fun.



The output of the blower escapes up through the back box and out the holes at the top. A system of closing off some of the holes is required. My complex system is a board with soft foam glued to one side.



So, if you are working on a smaller (low flow) piece like a carburetter, you will close off some holes to make the upper monometer sensitive enough to work well. When you log each test, you will list which holes were closed for that test.



As above the test piece would be mounted on an adaptor block, like a piece of 3/4" plywood with foam on one side. The test hole is large to account for nearly anything being tested. So most items will require an adaptor. The test piece to adaptor junction must be air tight. A method to clamp the edges of the adaptor down is good also. Since everything affects everything, the downstream end of the test piece will affect its performance. Think long and hard about making the adaptor look like the next part of the total system. Or even carv up part of a like system, to include in the adaptor, so that the junction of the test piece and adaptor is not part of the test.



A small change in the flow available through the test piece hole, will have a dramatic affect on the number of CFM leaving the blower. This change then causes a change in the air pressure inside the back box. This change in pressure will be seen as a large movement in the water column in the lateral monometer. In this drawing the red stained (food coloring) water will move from left to right when pressure in the box goes up.

Notice that the plastic bottle has a hole in its bottom that exposes the water to room pressure.



The exact angle of the latteral monometer determins its sensitivity. You experiment with that angle to see what you like.



Start each test with the throttle closed. If not, and the test piece is not a high flowing item, the vertical monometer will empty into the box. If you want fancy, you can rig up a float in line with the run into the front box to eliminate that problem. One end of the vertical monometer is open to the room and the other to the inside of the front box.



Turn on the blower with the throttle closed. With the test piece in place and clamped down, Open the throttle

slowly. Keep going until you see how much vacuum you can pull on the test piece. Go all the way to wide open if possible. Watching the vertical monometer. For example, say you can get 8" rise in the water column.



Then back off the throttle so as to have room for the improvements you will make. So, back off to say, 5" of water. Record that number. Now look at the lateral monometer. Has it been moving as you jack around with the throttle?. If not, close off a hole or two until you can see some movement. Just 1/4" is plenty.



Reinspect the vertical reading as you go along with your improvements. Adjust to 5" for each pass.



For clarity I have not shown every detail I could have. A closed loop monometer along the front and one side will work as your levels, and the closed loop prevents evaporation.



An additional monometer with a long hose and a length of 1/8" brake line can be used to find low pressure areas inside openings. Keep in mind that the act of inserting the probe with have an effect by itself. Go slowly or you will empty this one also.



A great lateral monometer is a long glass tube. Plastic works also but stains after a while.



The vertical monometer will be emptied a few times while you get the hang of things. After that you can change to a plastic bottle supply like the latteral monometer. The first time you forget the rules you will be shocked by the cloud or red water landing on everything.



You can add bits of measuring tape along each monometer to keep track of data.





Sears, Home Depot and Lowes have all of the flow bench parts.



Lynn E. Hanover

Bother. tidied up the garage now, so no excuse not to fit one of these. Silly question, but is there a suitable way to calibrate things without heading over with a test piece to a friend who has a superflo.



Bill

No.



The real good gizmo that gives very accurate readings costs a ton and is used on the intake side of the test piece. Fine for big 4 barrel carbs but not much else.



HVAC people have a similar gizmo to balance air conditioning systems, that you can fit over the outlet of the blower. Not quite as accurate but much cheaper.



I made up a bunch of square 3/4" plywood test pieces about 6" on a side, with differing hole sizes and a run of same size holes with inlet and outlet features different. Radiuses, tapers, inlet only, outlet only and so on.

I ran all of them on a Superflow. And recorded that data on each test piece.



I was driving from Columbus to Dayton on weekends to get time on Tom Pomeroy's superflow. (two time National champion in SuperVee, with no right arm and no feet) (Made Gengis Kahn look like an underacheaver).



That is where I got the smarts to build one. The diagram is in the superflow instruction book.



Write the flow rate and weather data on each test piece. Then when you want to know about how many CFM your pulling through a test piece, get out your calibrated test pieces and see how close you are to one of them. Correct for weather. Write it down.



After a while you will just work on improvements from item A to item B and won't care what the actual CFM is until no more improvement can be made. Then do the matchup to get a number. And write it down.



So you have a CFM number at the begining of a session, and again at the end. None of this is important unless you are in contact with another racer doing similar work, and want to compare performance over the phone.



You can make a flow bench that is much more sensitive than a Superflow. That short monometer with the steep angle is real hard to read a change. You make a long one just a few degrees above level, and it can detect a bee fart.



Most time will be spent between "made it worse, made it better". Use modeling clay to streamline things rather than grinding on an expensive piece. Then replicate the same surface contours as the clay with your die grinder. Polish like chrome when done.



I was wondering if anyone would use the plans.





Lynn E. Hanover

Oj I wo;; use them. Just don't know when. Been planning a home flow bench for 4 years now, just kids, job and megasquirt have gotten in the way (well when someone emails you wanting to put a T2 engine in an 1100lb kit car you just have to help them). In fact I have 3 sets of plans now. One from an old hot rod mag that uses 3 blowers and one from the internet that uses MAP sensors and a palm pilot to calculate flow. Between the 3 I should be able to work something out.



Now the old sofa has been evicted from the garage I have room for the bench. Just need time.

Just realised what the calibration gizmo is. Its a common or garden MAF, but with a superflow sticker on it and a cal certificate. Most of the common MAFs have cal curves available on line, although not to accuracy you need. In theory you could rip a GM MAF and ECU out the wreckers, pick up the scan tool off the web and hook it up a cheap and cheerful true flow meter.



The biggest problem with MAF is its not very sensitive at low flow rates as its a nearly exponential curve.



Hmm Got me thinking on something to try out. See now why I never get around to actually building a bench :-)

WOW!

Alot happened while I was gone. This is great reading material! https://www.nopistons.com/forums/pub...IR#>/bigok.gif



I have almost finished a new flow bench in my spare time. It is slightly different than your design. I'm using an old craftsman leaf blower, and instead of building a back box, I put a partition in the blower box(was that a good thing to do?). To adjust flow from the blower box I reused the intake cover of the blower and mounted it on the side. All I have left to do is to make up the manometers and backboard to mount them on. I'll try to get some pictures on later or tomorrow. Here is a simple drawing for now, and also, a link to a pdf manometer manual (tongue twister, eh?) from Meriam Istrument Co. It has all the basic instructions on proper usage and compesation.Link



Thanks again!





[attachment=34849:attachment]

Where?



This is just the info I need for my DIY EFI project.

What MAF is it?