Jack for Tcraft

[mhorowit]

Re: Jack for Tcraft

The only improvement that I can imagine would be a small telescopic tube that comes out of the long tube, toward the aft end of the aircraft once the handle is lowered completely. When this telescopic tube is extended, the plane cannot come down and the handle cannot accidentally be raised. It is a safety tube that prevents the jack from "over-centering" back down.

To keep the jack from tipping forward, the wheels need to be ahead of the support tube or the support tube need to lean backward a bit, right? a telescopic tube would simply add weight, correct? - Mike

[VictorBravo]

Re: Jack for Tcraft

To keep the jack from tipping forward, the wheels need to be ahead of the support tube or the support tube need to lean backward a bit, right? a telescopic tube would simply add weight, correct? - Mike

No, the support tube would make it impossible for the airplane to "over-center" and fall back down. The way his original design looks to me, if someone leaned on one of the wheels the wrong way, the plane would only have to move an inch or so forward before it could come down hard.

What you are saying is correct, the plane moves aft just after reaching the "top" of the arc, and so the plane's weight is behind the skateboard wheels. BUT, it does not take that much movement forward (like I said accidentally leaning on a tire or someone bumping the plane) to get it back to a "neutral point" where it could fall.

Adding the extra tube or arm in the manner I proposed means that no matter how hard you bumped the plane forward it could not tip back over onto the ground.

[Larry Lyons]

Re: Jack for Tcraft

I like this jack a lot. To keep it simple you might just leave a hole at the bottom to slide a screw driver in ( up inside the handle) once the jack handle is laying on the ground. A rather substantial screw driver handle would make quick lock to keep it from tipping back upright.
Larry

[Len Petterson]

Re: Jack for Tcraft

Jacks are good but to change bunges, we used a Engene hoist. Did the lift in the engine mount.
yeasterday I finiched lifting at the strut mount to do just one side, with a stand of 2*4 s. worked but!
Len

[Darren Lucke]

Re: Jack for Tcraft

Hey Tribe!
Thanks to Bob Waldron (for pics & idea) and all of you guys for the inspiration on this one - here's a pic of what I've come up w/ for Cubs, Champs, Luscombes, etc - no idea if it will work for TCrafts as of yet as I couldn't find one on the field when I went up yesterday to verify (my suspicion is I may have to modify for different height tires / and for TCraft as shown in Bob's pics w/ V shaped pin mount) - hope this helps someone -

http://www.tufindustries.com/images/gearjack01.JPG

Again - thanks for the inspiration and nod to build these - as you mentioned, I used the original idea and made one - now on eBay.

Sincerely,

[Bob Waldron]

Re: Jack for Tcraft

Darren,

Nice Jack. I like the triangular plate. If I made another one with tubes, I would add a triangular 'gusset', but your plate idea looks stronger. Looks like your rollerblade wheels are just a little further apart than mine are -- thats good, cause I think it provides a lot more lateral stability. Squared off skateboard wheels probably get another 1/2 to 3/4 inch spread.

I will be interested to find out how 'universal' it is. Did you have trouble with the wheels touching any of the airplane's tires?

My friend's has a section of steel tube welded across the top, that fits under the axel. I think he uses a piece of inner tube to protect the paint.

I couldn't find it on eBay. Hope that it sells well. Good luck.

[Darren Lucke]

Re: Jack for Tcraft

Thanks Bob!

Search "Gear Jack" and it should / may come up - in aircraft parts / accessories

They are actually a caster wheel w/o the caster, urethane rubber on them w/ roller bearings - one of the comments from the A&P's - "nice wheels" =P

I adjusted them a bit on the second prototype from the first - lifted an 8.00x6 on that Champ (loads of room - loads of oil on it for slipping from the strut, Cub works well w/ 8.00x4's but have to watch original brakes bleeder screws - clevelands on them would work great, Luscombe fit really nice even with wheel pants.

The tires never hit really as I allowed plenty of room from axle to tire centers - lifts up plenty high w/ most so far and can go higher - actually tucks under the wheel on that luscombe w/ 6.00x6 as it cams over to lock in position - to allow for taller tires I think I should be able to just add more "foot" as I have plenty of Cam Over Center action.

The first try on the Cub w/ 8.00x4's needed a bit more height on the foot of the jack - which is fixed for second generation!

Attached a pic of that Champ w/ 8.00x6's - handle removed for those who wanna tackle building one too!

[mulwyk]

Re: Jack for Tcraft

Verry nice jack, Darren. Good product. Congratulations...looks like a winner!

[Darren Lucke]

Re: Jack for Tcraft

Thanks - great inspiration! =P

[mhorowit]

Re: Jack for Tcraft

Could I suggest you warn the user a) to chock the other wheel and b) to loosen the tie-down? - MikeH

[VictorBravo]

Re: Jack for Tcraft

Darren ... here's another little bit of inspiration for you

See how complicated it would be to make the jack adjustable to fit "most" taildraggers. Some kind of jackscrew mechanism, or just two or three different holes that one bolt goes through that changes the distance between the roller wheel and the axle cup. (like an automotive jackstand, but with a pivot bolt a few inches away)

This allows you to sell the exact same product to a whole lot of different people. So one jack can be used for several different airplanes by a repair shop or FBO, where they might not have bought five different ones for different airplanes.

You also might think about adding another tab on the backside so you can install the handle tube as a safety device per my previous comment.

That being said, how much do you want for one of the Taylorcraft jacks as shown in your post? The ebay bids right now are lower than what it should sell for, and overly enthusiastic ebay bidders sometime drive up the prices higher than what reality is for the rest of us. Perhaps you can tell me what the "normal" price is, or the T-craft club price, or whatever.

Here's some more inspiration... you can sell an accessory to go with the T-craft version of your jack. Have someone sew up some strong nylon webbing, like a tow strap, into a harness that fits between the tires on a Taylorcraft. Use the TUF jack to raise one wheel, slide the harness over the wheel, repeat for the other side with the other half of the harness.

Now you have the wheels held together firmly, with the weight of the airplane holding the harnesses from slipping... and now you can replace the bungees with a FAR greater level of safety (airplane sitting on the wheels) and no possibility at all of the airplane falling off anything!.

I suspect this would compliment your bungee tool product pretty well.

Here's some more inspiration again... since your fabrication abilities have inspired me to put my brain to this!

You can make an "emergency field stand" for the bushplane guys. I'm thinking of something that hangs or ties on to the axle from behind ... then you go out and lift the wing struts until the tire comes up off the ground, and the stand swings down from gravity under the axle. When you let the wing down, the axle stand holds the tire an inch or two off the ground and you can remove the wheel or patch the tube or whatever.

This can be as simple as a piece of aluminum or Titanium plate folded into a U-shape with axle sized semi-circles cut into the ends of the U "tangs". Weight would be about 6 or 8 ounces as a guess for small tires, maybe a pound for the big bushwheels. It would allow some backwoods type of bush operator to plug up a tire or replace an inner tube sitting out in the dirt. Might be a lifesaver for someone stuck in the boonies.

This emergency light duty tool would be less convenient to use than the shop style jack you have already made... it should be a separate product.

If one of these ideas make you a bunch of sales, send me one If you become a multi-millionaire from them, buy the Taylorcraft type certificate and give it to the Foundation/Club.

Bill

[Darren Lucke]

Re: Jack for Tcraft

Bill (all of you),
Interesting stuff - let me tell you - the response on this has been pretty overwhelming, lots of questions, lookers, interest, etc.

When I get more time this evening - I'll post another few thoughts - pros / cons of refininement vs manufacture speed.

Love all of the ideas! More late this evening -
Darren

[Darren Lucke]

Re: Jack for Tcraft

OKay - full belly - coffee cup in hand.. here goes.

Here's the thoughts behind my jack - simple really, especially when I had Bob W's pics to design from.

Great Idea!

First step to anything! Great to see it in operation through stages of pics - my hat's still off to Bob Waldron (and a free jack if you want one - w/ similar mount to yours - I'll build it special and make it work)!

Fabrication speed

I wanted a faster way (by utilizing the CNC) to fabricate the jacks - in order to keep my costs down so I can sell them to the masses (faster to put a bit more iron in - and fabricate the way I have than to fit up tubes and weld them all - both end up strong but fitting tubes is less economical)

Fabrication Design

I have a CNC Plasma Table (amongst my other tools in the shop) that I'm always looking to put to work - design around this where possible

Shipping

I needed to have them shippable (why don't you all live in my town?) =P

Universal Use

I need to have them fairly universal in design so the basic design will work from one to the next - ie tcraft, cub, luscombe, etc with simple modifications to mounts, etc

Cam Over Action

I have a lot of cam over action - ie once it raises to maximum height - it drops down a fair amount too for stability - with this jack compared to Bob W's - the rear tab isn't really needed - I do have more concern for lateral stability - prob should say here that intended use is on hangar floors or nice flat asphalt on calm days - care should be taken while on jack and should be utilized with axle stands for added stability

Lateral stability

I could see in the pics that at the height Bob W's is that it sure wanted more lateral stability - I designed it to be wider (width can be a tradeoff tho) for more stability - hopefully not too wide that it will hit tires on most - also, because of the amount of Cam Over Action - the small tires actually can go nearly underneath (at least the bulge) of the aircraft tires and have adequate clearance

Refinements

Adjustability to height, this is a tradeoff to simplicity altho I like the idea of the pivot bolt with a height bolt on an arc to same to adjust. (KISS) Simplicity and ease of manufacture keep bringing me back to 2 different models - 2 different heights (maybe 3)
I've also kicked around having a pivoting axle saddle - altho this may be more design probs around stability

Price

That's the magic question when we get down to it - great original idea, hopefully some good modifications to make it faster to produce! I may be off-base but here are my thoughts -

The more universal it is, more mods / refinements it has raises the price - simple economics - more time, more parts = higher cost

The little guys (you and I, and most of us) do not want to spend more than we have / can justify on the tool - if it gets too high, we'll figure a way to build our own - even if it takes longer (like Bob W explained - we'll figure a way to make one)!

Some of us will want one right away if money is no object and we like the looks / idea / product!

Most of us will not need or want a universal jack as we only have 1 plane - and we don't want to pay extra for the universal fit -

FBO's operating and doing annuals will actually still need more than 1 unit as they'll be working (in most likelyhood) on more than one plane at a time, thus utilizing the correct height jack for the correct plane, etc and having multiple units will be no problem - financially speaking (I hope)

That all being said - and I've probably over-analyzed it - I do like the idea of a down and dirty quick one - for possible field use - altho I suspect not a highly used item as I would suspect if a tire goes down unless a simple puncture - the rest of the plane may need more attention. Maybe for the folks that have never made that big trip to Alaska - and are planning to... probably sell them all kinds of nifty items! =P but that's not what I like to do.

Anyhoo - there it is folks... my thoughts on it... now MY magical question.... How many of these, and what price would be fair to you all - the list users???? More quantity / group purchase helps me design around an adequate mount / price for everyone? (eBay does work quite well for the seller / buyer - market adjusts itself pretty much - basic idea of supply and demand)

Hope this helps - long post for a simple item.... let me know - off-list if you'd prefer - what one is worth and I'll do my best to provide a cost effective gear jack for everyone - here's my info -

[email protected]
701.720.3688

[fearofpavement]

Re: Jack for Tcraft

two thoughts: First on price, considering that the t-craft and other light airplane people tend to be tinkerers, the cost will need to be economical enough that many individuals will say, "Oh, I could make one, but for that price I won't bother." There will of course be some market for those that wouldn't or couldn't make a wheel chock but for the most part I perceive there is a lot of rudimentary fabrication capability out there that you will be competing against. From my own standpoint, I have made a large number of shop items but still buy them if the price is right because my time is limited.

Second, you had mentioned axle stands. That would be a great item to include in your "gear servicing kit". With just one axle stand, you could jack the tire, remove it and install the axle stand. Then go to the other side and use the jack on that side and remove that wheel assembly. Now you have both assemblies in hand to go to the clean up and repack area with the plane adequately supported and stable. It is going to take a long box to ship the jack in so an axle stand could go in there as well and it could be easily fabricated out of steel that you could cut with your equipment. Maybe a piece of pipe with a liner of leather, poly pipe, rubber or whatever to slip over the axle.Then you need to convince people that your method is superior to whatever people have been doing over the last 70 years.

[Robert Lees]

Re: Jack for Tcraft

My four thoughts:

1. What a great idea,

2. Will the lifting face on top of the jack be wide enough to aid lateral stability...and will the face scrape the paint off as it is rotated into position?

3. Will it fit under a flat tyre?

4. Can you make a nice cheap one out of titanium to get the transatlantic shipping costs down?