VFD Capra...Can I Still Call It A Capra?

[mjensen]

Originally Posted by Fricker08

Hey looking good man! That’s pretty wild and impressive. Hope you find someone to route that carbon fiber. I’ve been waiting over a month for my chassis from Procrawler out of Hungary because the place that was doing their work told them to pound sand. Granted it’s FR4 but I think probably close on properties.
Looking forward to seeing how this version works out for you


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Thanks! That's too bad about your chassis. Hopefully they will find another company to get the work done. I'm also looking forward to seeing how your build turns out. It's been one of my favorites on here.
No luck with the carbon fiber but there's a member here (JSterrett) that may be able to cut the rails out of aluminum for me. It will be a bit heavier but at this point that's not really a concern. We'll see.

[JSterrett]

Originally Posted by mjensen

Thanks! I had a set of aluminum rails that I hand cut out of 1/8" 6061 in one of my first designs. There's a picture of them back on the first page sitting on top of my box of rejected parts. They worked fine and were plenty strong but it was a lot of work to cut them so when I changed the design I decided to try the 3d printing route. I decided to go with 3mm carbon fiber for this latest design since while the 3d printed rails were quite stiff I question their durability. Plus I figured the carbon would be easier to hand cut and machine than the aluminum. It wasn't and it was also almost 3 times as expensive as the 6061.

I'm not set on the carbon and I think aluminum would work just fine. Maybe I could send you a copy of the design file, (not sure what file format you'd need, .step, .stl?) and you could tell me any changes to things like radius, hole sizes would be needed and give me an estimate of what it might cost, materials, labor, etc to make the rails out of 3mm or 1/8" 6061.

dxf would be easiest, or step. I'll need to buy some 3mm aluminum, as I don't have access to that thickness at work, but I have some other projects that need 3mm as well, so cost to you should be minimal.

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[mjensen]

Originally Posted by JSterrett

dxf would be easiest, or step. I'll need to buy some 3mm aluminum, as I don't have access to that thickness at work, but I have some other projects that need 3mm as well, so cost to you should be minimal.

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I can convert the file to .dxf without a problem. Hopefully the dimensions being metric won't be an issue. I tried to change the design to make it easier to cut. I've removed all the countersinks from the holes as I have a drill press. This should simplify things a bit. I've also made all the holes 3mm but in the event you don't have metric tooling 1/8" should be close enough. I've also made sure all the inside corners have a radius of at least 2mm. If there's anything else you think you might need let me know.
I've never used the private message thing here so I don't know if I can send a file with it. If not I'll send you my email address and go from there.

[JSterrett]

Originally Posted by mjensen

I can convert the file to .dxf without a problem. Hopefully the dimensions being metric won't be an issue. I tried to change the design to make it easier to cut. I've removed all the countersinks from the holes as I have a drill press. This should simplify things a bit. I've also made all the holes 3mm but in the event you don't have metric tooling 1/8" should be close enough. I've also made sure all the inside corners have a radius of at least 2mm. If there's anything else you think you might need let me know.
I've never used the private message thing here so I don't know if I can send a file with it. If not I'll send you my email address and go from there.

Yeah, just shoot me a PM with your email.

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[mjensen]

I got the Capra cage trimmed this morning and it fit surprisingly well. It still needs some tweeks, the 3d printed parts need some paint, and I need to redo the body panels but this is basically what the finished Capra will look like.

[mjensen]

A quick update. I had hoped to have some progress this past week. Unfortunately life got in the way but I want to thank JSterrett, a member here who, in spite on my ineptitude in figuring out how to send Fusion360 files, managed to cut me a great set of aluminum rails for the Capra. They look so good that it's really a shame that once the Capra is put together they won't be seen. I'm hoping to get them installed this week and finally get this project wrapped up.

[TheLetterJ]

You know you're doing things right when your end product looks more "factory produced" than the original, factory produced, product. I'm looking forward to hearing how this performs, it looks very well thought out. Keep up the good work!

[mjensen]

Originally Posted by TheLetterJ

You know you're doing things right when your end product looks more "factory produced" than the original, factory produced, product. I'm looking forward to hearing how this performs, it looks very well thought out. Keep up the good work!

I really appreciate the compliment but you're giving me far too much credit. This whole project has been a perfect example of someone getting in way over their head with something they (me) knew nothing about. I didn't even have a 3D printer when I started and knew nothing about them. Same for the CAD program, Fusion360. If this thing looks in any way professional it's a complete coincidence. Same for if it actually works. In the end it really doesn't matter because I've had a lot of fun working on it. Should it be a failure I've got a lot of nice parts I can put on something designed by someone that actually knew what they were doing.

[mjensen]

A quick update. I got all the mechanical things put together on the new rails. I debated about painting the rails to match the cage and in the end decided it looked better that way. Unfortunately the new body panels I ordered took some time to arrive so since I don't have a heated place to paint I wasn't able to paint them. In the end I took the body panels and interior off my other Capra so I could see how the truck was going to look. Now I just need to get the electronics installed.

[JSterrett]

Originally Posted by mjensen

A quick update. I got all the mechanical things put together on the new rails. I debated about painting the rails to match the cage and in the end decided it looked better that way. Unfortunately the new body panels I ordered took some time to arrive so since I don't have a heated place to paint I wasn't able to paint them. In the end I took the body panels and interior off my other Capra so I could see how the truck was going to look. Now I just need to get the electronics installed.

Very nice. Glad the rails worked out!

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[mjensen]

Originally Posted by JSterrett

Very nice. Glad the rails worked out!

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Thanks again for making the rails. They fit perfectly.
If there's ever anything I can do to help you out please let me know!

[Lashlee]

That looks killer!

[mjensen]

Originally Posted by Lashlee

That looks killer!

Thanks! I'm pretty happy with the way it looks but how it will drive, who knows. I managed to keep the Capra cage mostly intact so it still looks like a Capra which is what drew me to it in the first place and I made it easier to get to the mechanicals to work on, the biggest issue I had with the stock Capra. I'll admit, the VFD transmission was largely an impulse buy, I thought it looked like a neat system. It turned out to be a pain to actually get into the truck and have the clearances needed for links and the front drive shaft. I almost scrapped the idea a couple of times while I was trying to work things out. Eventually it worked out but it remains to be seen if it was worth the effort.

Anyway, I'm working on the electronics tonight and if the snow holds off I might actually be able to get it outside for a test drive this week.

[mjensen]

I got a Hobbywing Fusion system for my birthday (I had asked for an Axe system but I decided to keep the Fusion) and since it wouldn't fit in the stock Capra I decided to make it fit in the "sort of a Capra". The VFD transmission only has room for a 540 can motor and a while back I was thinking about trying to do something to fit a 550 motor in it. I decided against it at the time but the Fusion got me thinking about it again. This is what I came up with.

[mjensen]

With the holidays (and the loss of most of my recent Fusion 360 files, long story) I've not done a very good job of keeping this build updated.


But I wanted to wish all of you that might still be following this dumpster fire a Merry Christmas (or Happy Holidays, depending on your preference) and a Happy and more normal New Year.



Hopefully in the New Year I'll be able to wrap this project up and put an end to this far too long thread.

[JSterrett]

Originally Posted by mjensen

With the holidays (and the loss of most of my recent Fusion 360 files, long story) I've not done a very good job of keeping this build updated.


But I wanted to wish all of you that might still be following this dumpster fire a Merry Christmas (or Happy Holidays, depending on your preference) and a Happy and more normal New Year.



Hopefully in the New Year I'll be able to wrap this project up and put an end to this far too long thread.

Oh man, that sucks. I still have all the files you sent me if you need them.

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[mjensen]

Originally Posted by JSterrett

Oh man, that sucks. I still have all the files you sent me if you need them.

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Thanks Jeff. Most of what I lost were files for things to make the 550 length Fusion motor fit the rails you made me and the VFD transmission. I was using Fusion under an educational license I had from Autodesk for an Inventor course I took a few years ago when I was laid off. It expired unexpectedly and I wasn't able to cache the work I was currently doing, probably user error. When I install the free version of Fusion all my old files were there but nothing from the last month or so. I've slowly been trying to reproduce the lost files from derives of older files so all is not lost but it just takes time. Once the holidays are over I'll have more time to figure it out and if you do decide to try the build and want to put a 550 can motor in it let me know and I'll sent you all the updates.

[mjensen]

I'm honestly surprised this thread is still getting views and I apologize for not being able to update it. 2020 went out with a bang for my family with my elderly mother's house being gutted by fire a few days after Christmas. Fortunately she was fine and she was well insured but losing 88 years worth of belongings and mementos has been hard on her. So my retirement came to an abrupt end as I now need to deal with insurance people, cleaners, building contractors, etc which doesn't leave me much time for RCs.



I had really hoped to have the Capra done by now and I already had a new project planned using the TRX6 my dog got me for Christmas (not sure how he could afford it but I suspect he might have been dealing doggy treats down at the local dog park) Anyway, with my virus money I picked up a cheap CNC router and some 3mm carbon along with another VFD transmission and I figured on starting another year long excruciating trial and error build, this time with 6 wheels, to keep me occupied. Hopefully it will still happen but I doubt it will be anytime soon.


Thanks again for the interest in the Capra. I will definitely get it done eventually.

[GA Dawg]

Sounds like you have way more important things to work on than tiny trucks. Take care of what's important and let the other stuff come as it may.

[twade984]

Your dog sounds a little shady...

Sorry to hear about the fire, lack of hobby time is understandable. I look forward to updates on this, and future projects!