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Seesquare
08-07-2015, 12:43 AM
I am amassing the components for a Quadracer project, and have 2- 20" BMX- 48-spoke-wheels, with 3/8-inch axles. If I put a threaded adapter on the inboard axle-end, to beef it up to 14mm, as recommended in the plans, will that be adequate for loadbearing, & stiffness, for the front wheels?

Twinkle
08-07-2015, 04:59 AM
I am amassing the components for a Quadracer project, and have 2- 20" BMX- 48-spoke-wheels, with 3/8-inch axles. If I put a threaded adapter on the inboard axle-end, to beef it up to 14mm, as recommended in the plans, will that be adequate for loadbearing, & stiffness, for the front wheels?

The main problem is the cornering forces , there are many threads on AZ about using small size axles on trikes and quads , some bmx wheels ( especially the quando hubbed ones ) will accept a 14mm axle ( see my thread on using BMX and MTB parts to build front disc braked wheels )
http://forum.atomiczombie.com/showthread.php/8816-How-I-used-Standard-BMX-and-MTB-parts-to-make-my-pair-of-front-Disc-hubs?highlight=

I have used only 14 mm or 20mm wheels on all my builds but I have been looking at using HIGH TENSILE BOLTS on a pair of 10mm ballraced hubs with 11.8 stress rating
unfortunately the hubs would need to be modified to copy my idea ( unless you could find someone to machine some axles from silver steel but then I have not looked up the stress factor of Silver steel

(IT IS THE PITCH OF THE BOLTS THAT STOP YOU FROM USING STANDARD HT BOLTS )

http://forum.atomiczombie.com/showthread.php/9628-10mm-12mm-or-14mm-front-spindles-for-a-tadpole?highlight=10mm+12mm+axles

the problem with standard components is the material that they are made of and the stress at the point where it changes from 14 -10 mm will be the point of failure
standard axles are NOT designed to be single side mounted .


Sorry to put a downer on your idea but I hope I might have provided an alternative .

regards emma

Seesquare
08-07-2015, 04:41 PM
Thanks for the advice, Emma. Tell you what- I got nothing to lose by the attempt. If the adapter-ed axles fail, I will replace them with solid, 14mm axles. I just didn't want to disassemble the current wheels, & rebuild them, if I didn't have to! I measured the bore of the present hubs, & they are a shade small for just converting to the larger axle size.

Twinkle
08-07-2015, 04:46 PM
Thanks for the advice, Emma. Tell you what- I got nothing to lose by the attempt. If the adapter-ed axles fail, I will replace them with solid, 14mm axles. I just didn't want to disassemble the current wheels, & rebuild them, if I didn't have to! I measured the bore of the present hubs, & they are a shade small for just converting to the larger axle size.

Take care 10mm standard axles have been known to BEND


.........:taz:.............
:thinking2:


..................:oops:............. =.... :wheelchair:......

regards emma

Seesquare
08-07-2015, 08:59 PM
OK, then. While we are engaging in the conjecture on my options for life-&-limb, what about trying to bore out the hubs from the present 10mm (assumed to be 3/8-inch, here in The Colonies), to 14mm (again, about 9/16-inch), for larger axles? I could get an axle kit with cups & nuts. Think it would be safe or reliable? If not, I'm thinking, by the time I get a wide-flange, 14mm hub, get a set of shorter spokes, & reconstruct the bloody thing, I might as well just buy an assembled wheel. If that's the case, any recommendations on what I should look for, e.g., brand, # of spokes, rim alloy, supplier source, etc. & a reasonable cost estimate?

darnthedog
08-07-2015, 09:40 PM
So do you have a photo of the Contraption your looking to build maybe.

Mostly I will agree with Emma on the Wheels. The question is how much mass are you looking to move.

As to converting the 3/8 to larger axles is very dependent on the hub your looking to modify. Also it really depend on how you plan on mounting the wheels. When We are talking larger axles, We are referring to single side mounted wheels like those mounted on a Streetrunner, Streetfox and Warrior. If your mount wheels in a Fork or Rear triangle then the 3/8 wheel will work fine as they are supported on both side.

So as to using 3/8 Axles there is a time when you need them thicker and there are time when they are not. As pointed out if in a fork or the rear triangle.

So your question is sort of open ended as while we know a Quad racer it is not of a set of plans that is listed. So maybe a photo or a link or even a rough drawing would give you a better answer.

If your build a Streetrunner then Emma is correct in the bending of 10mm axles. And if your of a heavier mass or going to go ridge jumping then I would suggest moving up to 20mm axles to keep it all going.

By heavier mass I mean pushing 300 lbs. or more. Also if you 100 lbs or less the 3/8 may be perfectly fine. Hope the redefines it a little bit for you.

Seesquare
08-08-2015, 12:47 AM
Oh, I have a set of plans for the StreetFighter Quad Cycle Car, so that IS the design. Yes, there will be some mass to transport- roughly 190#, with a 34" inseam. Thanks for the comprehensive response, too. I want to keep within reasonable safety parameters, & promise not to go stump-jumping with the critter. Seems I will be using heftier axles, here. Guess I will need to either rebuilt my present wheels, or buying new ones. Is there a 14mm axle, 48-spoke hub, with only a 54mm flange available? That way I could reuse my spokes, at least. Or should a larger flange be used?

Twinkle
08-08-2015, 08:33 AM
Quando do a 48 and 36 hole version 14mm hub with approx 54mm flanges - I got a pair from the local tip ( 48 hole front disc braked rear with standard freewheel both 14mm spindles that are destine for our viking clone ) attached to the bmx bike a few months ago

regards emma

Seesquare
08-08-2015, 09:50 PM
Well, I am going to try some things out, and see where it leads. I can always invest in the assembled wheels, but what's the challenge in that? Maybe, to my wallet. I need to practice my welding skills anyway, & just getting the hang of the metallurgy & fabrication will be the test. BTW, I haven't looked extensively, but who is supplying the axle adapters for the freewheels & brakes these days? (Just lazy. Ain't what you know; it's who you know, right?)

Ticktock
08-09-2015, 08:32 AM
Hi,
Jumping in here without really reading all the posts (usually means you make a fool of your self) but the minimum axle size for any axle supported on one side, is 14 mm, and I would not build anything under 17 mm myself. Why , you may well ask. Well, I have bent 14, I have bent 16, I have bent 17, but I have not bent 20mm, except on a trials sidecar, and that does not count in this disscusion. And believe me, I was not trying that hard to bend these . If you use 14mm, you will , one day in the future, when you start to push harder, bend it.
I could not believe that I could bend a 17 mm axle in "normal " use, when it took all my effort and a bit of heat to bend it in the workshop, but it does happen.
Steve G
in Beijing for a while

Seesquare
08-09-2015, 10:22 AM
Yikes. That is a fairly discouraging commentary. So, where the h**l do you get 20mm axles & hubs, for 20-inch wheels?? Custom-made? Is there a modification anyone has done on the front-end of the StreeFighter to accommodate bilateral axle support?

darnthedog
08-09-2015, 12:12 PM
I'm going to point out that drum brake hubs from sturmey archer are only 10mm and used on commercial velomobiles that are fairly heavy. Danny C in UK just did a weekend ride using them. And he admits to being a bite portly. They are a pretty dense steel. But that is an expensive option I am willing to admit. $130 each hub which does not include the rest of the wheel. But they are really nice looking. Here are a photo of mine:http://s25.postimg.org/4h9jzwpd7/IMG_0907.jpg (http://postimg.org/image/4h9jzwpd7/)


Also I will point out this is for a Quad Streetrunner so weight distribution will play a big roll in not hurting the axles.

Also with the mass being carried under 200 lbs aka 90kg, the 14mm should be fine. 3/8 would be pushing it. 20mm will be overkill.

The really nice thing about building your own. YOU can use what you have and if it does not workout in test short distances you can pull it apart and redo it. Your not lock into anything specific.

Realize that mistakes and and will be made. This way your are not too disappointed when it does not work for YOU. As Danny has on his signature" Weld, Swear, Grind and repeat"

It it referring to the fact these are home made by ourselves and not in a machine shop by engineers for the most part. I mean there are a few here that are Engineers and a couple with machine shops. But for the most this is a hobby out of our backyards-garages- or basements in some cases.

Anyway try it you'll love it.

Twinkle
08-09-2015, 02:52 PM
The S-A axles were designed for single sided use in wheel chairs and as my thread with the 10 ,12 etc axles stated IF THE SPINDLE IS HARD ENOUGH then it should work BUT NORMAL BIKE SPINDLES ARE SOFT METAL ,

regards emma

darnthedog
08-09-2015, 04:47 PM
The S-A axles were designed for single sided use in wheel chairs and as my thread with the 10 ,12 etc axles stated IF THE SPINDLE IS HARD ENOUGH then it should work BUT NORMAL BIKE SPINDLES ARE SOFT METAL ,

regards emma

Agreed- Ticktock had him jumping for 20mm Axle. Wanted to reassure him that there are other experiences with smaller axles from 20mm. Your Experiences with 14 to 20mm axles on your multiple tadpoles with Lithium to Lead speaks louder than words themselves. :rockon:


The Streetfighter plans actually outline the use of 14mm axles. Page 18 in case your looking for that specification. I have the plans as one of my kids wanted me to build it for him. But he change his mind after I got the plans. I may still build it some day when not tied up with other commitments.

Seesquare
08-09-2015, 05:48 PM
Thanks for all the input. I have 7 parcels of various parts on order, due to arrive in the next week-or-two. Wheels, axles, adapters, nuts, etc. Should be fun. I even found a welding mentor. Need to plan the trip to the steelyard, pretty soon.

Twinkle
08-10-2015, 06:51 AM
Wheels don't have to be expensive
These cam from the local tip still attached to a broken BMX bike , the front wheel was a quando 48h disc braked hub with 14mm spindle and the rear had a standard size screw on freewheel , I just replaced the freewheel with a screw on disc adapter and a pair of front wheels for my viking
here is the good bit _ bike from the tip 6 , freewheel adapter 3 and the pair of disc rotors came from another bike from the tip total cost in the secondhand tyres from the original BMX was 12 or approx 18$

http://s15.postimg.org/rhwkr1qqj/48spokebmxwithdiscs.jpg (http://postimg.org/image/5vhka0s5z/full/)
img host (http://postimage.org/)

BTW - Left hand wheel was the rear wheel with the screw-on adapter not direction of "handed disc rotors "..

regards emma

Seesquare
08-10-2015, 09:56 AM
Very good to know. Thanks, Emma! I will be scouring the 2nd-hand establishments. The adapter for the freewheel is a pretty-nifty gizmo.

Seesquare
08-16-2015, 04:09 PM
Well, I reamed out the 10mm holes in two 48-spoke BMX wheels, replaced the loose bearings with some smaller ones (originally had nine, now 11), & now have 2 wheels with 14mm axles. So, it's a start. They may not hold up, but what the heck- live & learn. :rockon:

Twinkle
08-16-2015, 05:40 PM
Well, I reamed out the 10mm holes in two 48-spoke BMX wheels, replaced the loose bearings with some smaller ones (originally had nine, now 11), & now have 2 wheels with 14mm axles. So, it's a start. They may not hold up, but what the heck- live & learn. :rockon:

That is how I did a couple and they were OK

regards emma