Any suggestions on reinforcing the landing skid mounting tabs

[dpinvidic]

The most likely reason for frame replacement (for me anyway) has been broken tabs on which the landing gear struts mount. Has anyone come up with a trick to reinforce these tabs so they don't break as easy.

I was even considering putting saw cuts in the white plastic landing gear struts just so that they would break easier and save the frame. It is just so much work to transfer everything to a new frame.

Thanks,

Dan

[dpinvidic]

NEVER MIND...Finaly got a good search result and found some old threads....

[TowPilot]

Glad you found the old threads.

I don't know which you found so I'll post a couple ideas.

To repair the frame when broken in the front, I've done this to give it more life until the frame needed changing:

https://www.helifreak.com/attachment...8&d=1256320770


https://www.helifreak.com/attachment...7&d=1256320770


https://www.helifreak.com/attachment...6&d=1256320770


Then covered the zip ties with epoxy or shoe goo would work too.

https://www.helifreak.com/attachment...0&d=1256320807


https://www.helifreak.com/attachment...9&d=1256320770


To prevent tabs from breaking off, just use zip ties so the zip ties fail before the tabs do (usually).

May need to slightly enlarge the holes in the skids to be the zip ties to work. These are Trex 500 skids but this works on stock skids too.


https://www.helifreak.com/attachment...2&d=1256319101


https://www.helifreak.com/attachment...0&d=1256319101


https://www.helifreak.com/attachment...9&d=1256319101


https://www.helifreak.com/attachment...4&d=1256319143

Sorry, the photos were not taken to specifically show the zip ties but you get the idea.

Mike

[Andrew73]

I've been wondering about this as I don't fancy trying to replace a frame. I've seen racing cars where the rear wing (fender) is attached with nylon bolts rather than metal ones so that they break on impact rather than ripping the bodywork. I wonder if we could do the same with the B400's landing gear bolts? What size are they?

[dpinvidic]

Originally Posted by Andrew73

I've been wondering about this as I don't fancy trying to replace a frame. I've seen racing cars where the rear wing (fender) is attached with nylon bolts rather than metal ones so that they break on impact rather than ripping the bodywork. I wonder if we could do the same with the B400's landing gear bolts? What size are they?

.

You would need to drill the skid struts for 2mm. but can you find 2mm nylon screws.
2/56 is a touch larger, but you might have better luck finding them in nylon.

But along this line of thought...how about mounting ball studs in the tabs, pointing down. Then drill a tight fitting hole in the landing skid. If you could get a "snap on" skid, that might be the answer. It just has to stay on in flight...maybe tie some monofiliment line to hold it together. Just a wacky thought....

Dan

[dpinvidic]

Originally Posted by TowPilot

Glad you found the old threads.

Sorry, the photos were not taken to specifically show the zip ties but you get the idea.

Mike

How have the zip ties worked out after a crash? I thought they were pretty strong, do they break before the tab does?
Thanks for the Pic... they gave me some ideas on wire routing.

Dan

[Stanleyc1]

I use 2mm nylon screws so they shear off

[fishboy77]

+1 I use cheap 2.5mm zip ties I got off ebay. They always break before that tabs do. If you can find 2mm that should be even better.

[Andrew73]

Something like this? They are 2mm by 10mm. Has anyone crashed with nylon bolts who can confirm they break first?

[dpinvidic]

I was lazy this morning, so I just drilled a couple of 3/32 holes in each strut. The hope is that the strut will break first. But I also ordered some 2mm zip ties. If the ties usually break first, it will save both the strut AND the tab.

[TowPilot]

Originally Posted by dpinvidic

How have the zip ties worked out after a crash? I thought they were pretty strong, do they break before the tab does?
Thanks for the Pic... they gave me some ideas on wire routing.

Dan

I've never lost a tab or skid due to the zip ties not breaking.

Use the smaller zip ties for easy of installation due to drilling out the holes in the skids and to assure the zip tie will break.

I worried about that too when I was first told about zip ties.
The idea came from someone in Australia.

While you can't break the zip tie easily pulling on it, they seem to shear readily on impact.

Monofilament line would work too.

The nylon bolts might not shear as easily.

[Andrew73]

I've installed the 2mm nylon bolts, nice easy mod just had to drill out the holes on the landing gear. Feels nice and secure but the bolts seem quite breakable. I doubt it will be long until we find out if they work!

[dpinvidic]

Originally Posted by Andrew73

I've installed the 2mm nylon bolts, nice easy mod just had to drill out the holes on the landing gear. Feels nice and secure but the bolts seem quite breakable. I doubt it will be long until we find out if they work!

Very nice job....

[Stanleyc1]

Had my B400 for 2 Years have not replaced the main frame as of yet. Do have 500 skids on it. Do not know if it makes a diff, but I had the B400 skids on it untill last year and no broken tabs. You know I just jinxed myself with this post.

[banditpowdercoat]

Get a set of Protos 500 Skids, Not as large and ugly looking as Align skids and more flexible

Here's mine

[dpinvidic]

Originally Posted by TowPilot

I've never lost a tab or skid due to the zip ties not breaking.

Use the smaller zip ties for easy of installation due to drilling out the holes in the skids and to assure the zip tie will break.

I worried about that too when I was first told about zip ties.
The idea came from someone in Australia.

While you can't break the zip tie easily pulling on it, they seem to shear readily on impact.

Monofilament line would work too.

The nylon bolts might not shear as easily.

Well, got the zip ties from e-bay yesterday, and put them on tonight. I had thought it was a good idea, but now that they are on, it looks like it will be perfect.

The 2mm ties are not that strong....but plenty strong to keep the sikds on....I hate to say this, but I am "Almost" looking forward to testing it.....

By the way, in a crash last week, I broke both skids becasue I had drilled holes to weaken the skids...so that worked OK, at the cost of new skids.
But this is WAY better....

Thanks Again.

Dan