P-51 Hotas Anyone?

The handle assembly is almost finished...just needs a rubber grip!

As you can see by the picture of me holding it, pilots back in the 40's must have had small hands! It's just barely 4 fingers wide...so my hand will be coming off the end once it is attached to the lever. I may have to customize mine for a more comfortable ride! Maybe that is why they told me I couldn't be a fighter pilot all those years ago....since 6'5" is apparently too tall for an F-18 cockpit :(

Also finished the arm for the throttle lever.

Awesome! That is interesting how small the handle is. I remember walking through the WWII uniform section at the Smithsonian Air and Space Museum and thinking the same thing... People were smaller back in the 40's.

Awesome! That is interesting how small the handle is. I remember walking through the WWII uniform section at the Smithsonian Air and Space Museum and thinking the same thing... People were smaller back in the 40's.

Speak for yourself - I'm only 5' 10"! From being in the cockpit of a couple of Mustangs, the throttle is small, but the positioning of it does make it really quite comfortable. Your wrist tends to sit a little lower than the handle and you use the base of your fingers to push it forwards. I'm sure if you get it mounted correctly, you'll find it more than comfortable :)

How are you intended to make the rubber grip? I imagine that being quite a challenging process?

Speak for yourself - I'm only 5' 10"! From being in the cockpit of a couple of Mustangs, the throttle is small, but the positioning of it does make it really quite comfortable. Your wrist tends to sit a little lower than the handle and you use the base of your fingers to push it forwards. I'm sure if you get it mounted correctly, you'll find it more than comfortable :)

 

How are you intended to make the rubber grip? I imagine that being quite a challenging process?

Yeah from the Mustangs that I have been in the size of the throttle has never been a thing for me,

Getting your feet down to the rudder pedals without hitting the gear lever, now thats a challenge!

Pman

Yeah from the Mustangs that I have been in the size of the throttle has never been a thing for me,

 

Getting your feet down to the rudder pedals without hitting the gear lever, now thats a challenge!

 

Pman

Thus the reason to lock them when you shut down :)

Awesome! That is interesting how small the handle is. I remember walking through the WWII uniform section at the Smithsonian Air and Space Museum and thinking the same thing... People were smaller back in the 40's.

I think they were even smaller in the early 1900's. One of the houses I lived in was built in the early 1900's. The door frames were only 6 feet high...I'm surprised I don't have a permanent dent in my forehead from living there!

Speak for yourself - I'm only 5' 10"! From being in the cockpit of a couple of Mustangs, the throttle is small, but the positioning of it does make it really quite comfortable. Your wrist tends to sit a little lower than the handle and you use the base of your fingers to push it forwards. I'm sure if you get it mounted correctly, you'll find it more than comfortable :)

 

How are you intended to make the rubber grip? I imagine that being quite a challenging process?

Hopefully as you said it will feel more comfortable once it is finished and in the right position. I guess you're probably not supposed to have a death grip on it anyway!

For the rubber grip, I am going to try my hand at rubber casting. I have sourced some castable rubber which is the same durometer as that used on the original, but is a different material. It will be made from urethane, so it may not work out so well for someone who is sensitive to that material - apparently some are sensitive to urethane as others are to latex. If the molding fails, I will be trying to source a stock grip which is as similar to the original as possible.

Yeah from the Mustangs that I have been in the size of the throttle has never been a thing for me,

 

Getting your feet down to the rudder pedals without hitting the gear lever, now thats a challenge!

 

Pman

How does the P-51 cockpit compare in size to one half of a Cessna 150? It was a tight squeeze for me in a 150...I could barely keep my feet off the rudder pedals and my thighs low enough to clear the yoke so that the pilot could fly. I basically had to sit frozen in one position so I didn't inadvertently start messing with the controls.

 

 

How does the P-51 cockpit compare in size to one half of a Cessna 150? It was a tight squeeze for me in a 150...I could barely keep my feet off the rudder pedals and my thighs low enough to clear the yoke so that the pilot could fly. I basically had to sit frozen in one position so I didn't inadvertently start messing with the controls.

Its abit bigger then a 150 cockpit, its more akin to a 172 half really.

Im 5ft 8 and I was quite comfortable in it. Granted the back of a TF51 was more compact then the P51C or the D.

As for locking the lever, doesnt stop you kicking it though does it ;)

Pman

 

If the molding fails, I will be trying to source a stock grip which is as similar to the original as possible.

 

 

What about 3d Print?

The original ribber grip was molded over the metal handle probably almost exactly like you are going to do with the urethane. As long as the urethane has close to same durometer and color this should work fine.

It looks like you are getting up a good head of steam on your progress. Of course, things always seem to slow down when it is time to pull all of the little details together. Hopefully those of us that are on the list for some of the first production run will be seeing the results first hand sometime soon. But knowing how complicated this type of project can be I think a realistic best case expectation is perhaps in two to three months and it wouldn't surprise me if it was early fall before the first units are shipped.

I am really looking forward to getting mine and I wouldn't mind being surprised by an earlier than expected ship date.

About pilot size. Not only were people in general smaller in the 1940s but the USAAF had size limits on fighter pilots. As a result they were smaller on average than the general population and none of them were big by standards of the day since larger individuals were not selected for fighter pilot duty.

What about 3d Print?

I may be wrong, but I'm not aware of any rubber which is 3d printable since most rubbers are usually 2 part thermoset resins. There may be a softer plastic which would work sufficiently as a grip though... that may be an option for a limited run. There is always the option of the diamond knurled steel "service order" grip, but I'd prefer the rubber for long flights for sure.

UPDATE: actually a quick google search would have shown me that there are "rubber like" 3d printable materials readily available, so ignore my comments above!

The original ribber grip was molded over the metal handle probably almost exactly like you are going to do with the urethane. As long as the urethane has close to same durometer and color this should work fine.

 

It looks like you are getting up a good head of steam on your progress. Of course, things always seem to slow down when it is time to pull all of the little details together. Hopefully those of us that are on the list for some of the first production run will be seeing the results first hand sometime soon. But knowing how complicated this type of project can be I think a realistic best case expectation is perhaps in two to three months and it wouldn't surprise me if it was early fall before the first units are shipped.

 

I am really looking forward to getting mine and I wouldn't mind being surprised by an earlier than expected ship date.

 

About pilot size. Not only were people in general smaller in the 1940s but the USAAF had size limits on fighter pilots. As a result they were smaller on average than the general population and none of them were big by standards of the day since larger individuals were not selected for fighter pilot duty.

There is some pretty good progress being made, however there still are a few challenges in the way. I'm trying my best to have a working prototype by the end of the month which I can begin testing. That may be a stretch since sometimes real life can get in the way. I have 3 major components to finish and then to start fitting things together and working on the electronics.

I'm currently on hold right now as all of the snow which is now currently melting is causing some issues...minor flooding in the workshop. Not full on flooding just minor "puddles" which should subside over the next few days I hope, then I can get back to work!

I might get booed off this thread for suggesting this, but if the rubber thing becomes a major hang up you could always go with that wrap they use on road bikes. It wouldn't be lagit but it would be functional for a limited run.

I might get booed off this thread for suggesting this, but if the rubber thing becomes a major hang up you could always go with that wrap they use on road bikes. It wouldn't be lagit but it would be functional for a limited run.

The problem with that is that the rubber is actually fairly substantial and has heavy ribs modeled in. The handle bar wrap would not be very close to the overall size and feel of the original rubber.

I don't think that the urethane molding process is going to be a major hang up. After all we are talking about something that was built in quantity in the early 1940s so it's not like the process they used is high tech or anything. With modern urethane products it should be even easier than it was back in the day when they had to vulcanize the rubber onto the handle. Having looked at the blue prints for this I am fairly certain that making all of the metal parts that has been going on for some time now is a much bigger challenge than coming up with a suitable "rubber" handle process.

...There is some pretty good progress being made, however there still are a few challenges in the way. I'm trying my best to have a working prototype by the end of the month which I can begin testing. That may be a stretch since sometimes real life can get in the way. I have 3 major components to finish and then to start fitting things together and working on the electronics. ...

Since you are about to start looking at the electronics I will chime in with a suggestion. Please feel free to ignore it for what ever reason.

I am assuming that you will be using an off the self controller chip and maybe even an off the self controller board like the Leo Bodnar units. If that is not the case then don't bother reading the rest of this post.

If you are going that route then it would be great if you exposed (some of) the unused axis and button inputs since you will only be using a subset of these for throttle functions (3 axis and one button input out of 8 axis and 32 buttons available). The reason this would be a good thing is that this would make it possible for users to easily add things like trim controls and various switches to a virtual cockpit by tapping into the throttle's joystick boards unused capacity.

On that note, I'm sure you have thought this through, but I would suggest a teensy 2.0 controller. It is just about as small as they come. Completely customizeable, more than enough inputs for a HOTAS, oh and did I mention it's only $16?

http://www.pjrc.com/store/teensy.html

I've played around with them a lot so if you want to know more about my experience with it just let me know. There is some programming involved but it's really easy and I wouldn't mind doing it if you need help.

Very cool to see more progress - must have missed the last post. Keep up the good work! :)

Out of interest, how are you planning to give the stick some tension (If that's the right term?), Springs?

The problem with that is that the rubber is actually fairly substantial and has heavy ribs modeled in. The handle bar wrap would not be very close to the overall size and feel of the original rubber.

 

I don't think that the urethane molding process is going to be a major hang up. After all we are talking about something that was built in quantity in the early 1940s so it's not like the process they used is high tech or anything. With modern urethane products it should be even easier than it was back in the day when they had to vulcanize the rubber onto the handle. Having looked at the blue prints for this I am fairly certain that making all of the metal parts that has been going on for some time now is a much bigger challenge than coming up with a suitable "rubber" handle process.

Well, the minor spring flooding turned more serious...the puddles turned into several inches of water in the shop so I am only getting back to work now. Started working on a rough mold for the rubber handle, so hopefully in the next couple days I'll have an actual grip...fingers crossed!

Since you are about to start looking at the electronics I will chime in with a suggestion. Please feel free to ignore it for what ever reason.

 

I am assuming that you will be using an off the self controller chip and maybe even an off the self controller board like the Leo Bodnar units. If that is not the case then don't bother reading the rest of this post.

 

If you are going that route then it would be great if you exposed (some of) the unused axis and button inputs since you will only be using a subset of these for throttle functions (3 axis and one button input out of 8 axis and 32 buttons available). The reason this would be a good thing is that this would make it possible for users to easily add things like trim controls and various switches to a virtual cockpit by tapping into the throttle's joystick boards unused capacity.

The ready made units like Leo Bodnar's would be a significant additional cost, which I am hesitant to go with since I'm a little worried about what the final cost of the quadrant will be after I now realize how much time and material it takes to make one :huh:. I don't want to ignite the PIC vs. AVR war on this thread, but I have done some limited joystick development with PIC, so a custom PIC controller will probably be the route I take...at least initially. I started programming with basic many many years ago...so now I feel most comfortable with PicBasic. In any case, the controller will be open source hardware/firmware so whoever wants to modify/port it will be free to do so. Whichever PIC I choose in the end for the board will have all pins broken out so anything which is unused will be available.

On that note, I'm sure you have thought this through, but I would suggest a teensy 2.0 controller. It is just about as small as they come. Completely customizeable, more than enough inputs for a HOTAS, oh and did I mention it's only $16?

 

http://www.pjrc.com/store/teensy.html

 

I've played around with them a lot so if you want to know more about my experience with it just let me know. There is some programming involved but it's really easy and I wouldn't mind doing it if you need help.

I actually have a teensy 2.0 (and one of the other teensies) but haven't really had time to play around with it much. Like I discussed above, the controller will most likely be a PIC since I have some experience with it (haven't got around to learning C on the AVR yet), but it probably wouldn't be hard to port it over to a teensy since the joystick descriptor is really the main part of the firmware.

Very cool to see more progress - must have missed the last post. Keep up the good work! :)

 

Out of interest, how are you planning to give the stick some tension (If that's the right term?), Springs?

The lever friction is set by the two knobs on the front of the quadrant by squeezing each lever between a set of brass "friction plates". Turning the knobs causes a threaded cylinder to apply more or less spring pressure to the plate/lever stacks to increase or decrease the friction. The springs are similar to a disc washer or belleville....you can see them in a previous post (they look like 6 legged spiders). I believe they should allow the levers to go from almost no resistance to full lock.

I actually have a teensy 2.0 (and one of the other teensies) but haven't really had time to play around with it much. Like I discussed above, the controller will most likely be a PIC since I have some experience with it (haven't got around to learning C on the AVR yet), but it probably wouldn't be hard to port it over to a teensy since the joystick descriptor is really the main part of the firmware.

Well if you become interested, just let me know. I am working on a switch panel and I use the Teensy++ 2.0. I took a c++ class about 8 years ago back in college and thats it. In a short amount of time I had it up and running (its still WIP though). The 2.0 board has something like 16 digital inputs and 6 axis (I think). I could make you a custom driver and script that could essentially make your teensy board plug and play. The drive could be written so when you plug your HOTAS in it will show up in your control panel as LOGICNC P-51 HOTAS or something, and when you open it in the game controler setting only the IO inputs and axis you want will show, there won't be any inputs that are unused. I'm not an expert at this kind of thing but given it's size, price, plus its customization features I don't know how you could do better. It's really easy to even program toggle switches so they do a momentary pulse instead of a constant on signal which is essential for simulator applications.

Well if you become interested, just let me know. I am working on a switch panel and I use the Teensy++ 2.0. I took a c++ class about 8 years ago back in college and thats it. In a short amount of time I had it up and running (its still WIP though). The 2.0 board has something like 16 digital inputs and 6 axis (I think). I could make you a custom driver and script that could essentially make your teensy board plug and play. The drive could be written so when you plug your HOTAS in it will show up in your control panel as LOGICNC P-51 HOTAS or something, and when you open it in the game controler setting only the IO inputs and axis you want will show, there won't be any inputs that are unused. I'm not an expert at this kind of thing but given it's size, price, plus its customization features I don't know how you could do better. It's really easy to even program toggle switches so they do a momentary pulse instead of a constant on signal which is essential for simulator applications.

Thanks for the offer...I'll let you know if I run into trouble. Perhaps you could be the first one to port the controller from Pic to AVR!

After a long layoff due to shop flooding - drying out - flooding - drying out - repeat... I am finally back at it again. After two failed attempts at building a mold for the rubber grip, the third was pretty successfull. There is one void in it near the flange on the opposite side, but it looks pretty good for a first attempt. The mold was a sacrificial one...I had to destroy it to demold the finished part. The rubber looks and feels just like I had hoped, so it looks like a replica grip will happen on the production units. I'll just have to create a production mold for doing it.

Dang man that looks awesome! Keep it up.

Cheers for the update, looking good!

Throttle Lever Complete

The throttle lever is complete! - minus electronics.

I have to say VH-Rock, you were right... now that it is fully assembled it actually feels pretty good as far as the handle size is concerned.

Great to see the pieces coming together now - it looks fantastic!

The stang is a very nicely laid out aircraft. Lots of room, comfortable and everything seems to be in the right place

Main bracket assy is complete. One more part and then it's assembly and electronics time!

Main bracket assy is complete. One more part and then it's assembly and electronics time!

 

Man I can't wait to see. Thanks for continuing to update your progress.

Wow that bracket is quite tricky. I guess you didn`t cast it, but welded it. It had to be some hours of fiddling. Good job!