# Your ideas for a shop made O/A hand truck?



## erikmannie (Nov 6, 2022)

I have a gas welding cart. I will post pictures of it below. It is great, but I am going to buy an extra acetylene as well as oxygen cylinder, and I want to make a dual cylinder hand truck. 

This will be nice for me because I will wheel the hand truck to the side yard, as I never use O/A inside the shop. 

There is no need to cart *all* of the brazing, welding, and cutting accessories with me because I am only doing one process at a time.

I want to make such a hand truck from scratch. Do you guys have any ideas for this?


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## Firebrick43 (Nov 6, 2022)

So all 4 cylinders at the same time?


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## erikmannie (Nov 6, 2022)

All I need it to do is safely & securely hold the 2 cylinders. That is, I do not require it to hold any equipment such as hoses, torches, goggles, etc.


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## erikmannie (Nov 6, 2022)

Firebrick43 said:


> So all 4 cylinders at the same time?



No, the “dual cylinder O/A hand truck” that I am going to build will hold one acetylene cylinder and one oxygen cylinder, the exact sizes of which are shown in the photos above.

I know that I can buy one of these, but what fun would that be?


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## markba633csi (Nov 6, 2022)

I built one once by cannibalizing a shopping cart- but bigger wheels are a must; gotta buy those


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## Ken from ontario (Nov 6, 2022)

One inch thin wall square tubing is what I would use and since there's no need for extra compartments /storage, a (T) shape dolly with a tray on the end (to hold the two bottles) is all you need really, I would use bigger diameter wheels like 8"-10"  and also I would weld a piece of angle iron near the bottom  so you could put your foot against it to tilt the dolly on the two wheels, makes moving it a bit easier.


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## den-den (Nov 6, 2022)

Large wheels!!  Moving it outdoors, over bumps etc will be far easier and safer with big wheels.  Anything from commercial wheel-barrow size wheels up to 20" diameter will be great.


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## General Zod (Nov 6, 2022)

Mine:  *oxy-acetylene cart**. *I call it a "cart", but it's more like a hand truck.


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## Aaron_W (Nov 6, 2022)

For what you describe I'd probably start with a good heavy duty hand truck and modify to your needs. It will probably be cheaper to start with a hand truck than fabricating the whole thing from scratch. Agree with Den-Den on the large tires.

Make sure you have a way to secure it at both the storage and use locations.

Something like this to start with, the wheels alone could cost you $40-100 so at least half the material cost is covered when buying the hand truck.

Milwaukee 800lb hand truck


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## erikmannie (Nov 6, 2022)

General Zod said:


> Mine:  *oxy-acetylene cart**. *I call it a "cart", but it's more like a hand truck.



That video is pretty much what I had in mind for my project. Do you mind if I copy your idea, modifying it for my needs?

Were there any changes that you wish you would have made after using this O/A cart?

I would probably use .090” wall tubing & 3/32” stick electrodes (for speed and because SMAW is my favorite welding process).


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## Firebrick43 (Nov 6, 2022)

I second the large wheels.  The first project I made when I was out on my own was a 2 wheel torch cart.  I made the 10" steel wheels and every time I use it I wish it had 26" wheels.


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## francist (Nov 6, 2022)

The mention of 26” wheels made me think of the old firefighting cart they had at my hometown airport (small town, two police cars, you get the idea) that had the dubious honour of being the worst equipped commercial airport in the province. But I digress, here’s kind of what they had out beside the runways but older. Might give you some ideas for the O/A tanks rig?

-frank


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## General Zod (Nov 6, 2022)

erikmannie said:


> That video is pretty much what I had in mind for my project. Do you mind if I copy your idea, modifying it for my needs?
> 
> Were there any changes that you wish you would have made after using this O/A cart?
> 
> I would probably use .090” wall tubing & 3/32” stick electrodes (for speed and because SMAW is my favorite welding process).


Go right ahead, knock yourself out. 

I think the only thing I would change would be the height. As it is, I put the axle rod such that the base is about 1/2" off the floor.  Not that it really matters all that much since that back tube swings upward to moment you tilt it, but I think I should have had it perhaps 1" off the floor, with some short feet on the other free corners to keep it level when it sits.    If you get your cuts perfect with zero-gap fits, 3/32" rods will work great.  As for the wheels I might have used larger wheels if I didn't already have these sitting here.  I bought them a while back at Harbor Freight and figured might as well use them instead of collecting dust in the garage.


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## erikmannie (Nov 6, 2022)

General Zod said:


> Go right ahead, knock yourself out.
> 
> I think the only thing I would change would be the height. As it is, I put the axle rod such that the base is about 1/2" off the floor.  Not that it really matters all that much since that back tube swings upward to moment you tilt it, but I think I should have had it perhaps 1" off the floor, with some short feet on the other free corners to keep it level when it sits.    If you get your cuts perfect with zero-gap fits, 3/32" rods will work great.  As for the wheels I might have used larger wheels if I didn't already have these sitting here.  I bought them a while back at Harbor Freight and figured might as well use them instead of collecting dust in the garage.



If you are welding .090” square tubing with 3/32” stick electrodes, what would you say is a good range for the gap in the fit-up? 

I would obviously not bevel the .090”. I like some gap (at least a few thou) for this thickness. At any gap above .050”, I am *seriously* questioning my fit-up skills. .063” and up and I am unhappy with the situation.


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## FOMOGO (Nov 6, 2022)

my dad made one with 14" car tires, and wheels. He had a large shop, and did a lot of work on his own heavy equipment. It had the big acetylene, and oxy tanks. It was a pleasure to move around, It got rolled outside a lot. Mike


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## erikmannie (Nov 7, 2022)

I did an exhaustive Google search to look for any other ideas, but I came back to the @General Zod plan.

I must be picky because I found *nothing* online that I would buy.

I watched the video from @General Zod again, and once I saw those lengths of square tubing laying on the table, my mind was made up!

Since everybody has recommended large wheels, I will probably use 26” bicycle wheels. There is a bicycle recycling shop in town, & I’m sure that I can buy a pair of MTB wheels for very cheap.

I am sure that my lathe will see some action for the axle.

Since it is an oxyacetylene cart, I think I am obligated to torch cut the square tubing as well as gas weld everything, which I am happy to do.


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## erikmannie (Nov 7, 2022)

If you guys have any ideas about the handle, a foot kicker or how I might chain the cart to the wall, I welcome any input.

I live extremely close to the San Andreas fault line, & my sweet mother-in-law lives directly above my shop, so we don’t want any lapses in safety.


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## Just for fun (Nov 7, 2022)

I wouldn't use the torch to cut the material.   If you have a band saw use that and tig weld it, it will look so much nicer. 

As far as a handle goes, I would come off of the cart with two pieces of flat iron and a piece of pipe between them. 

To anchor it to the wall I would install two eye bolts to the wall and use a chain.


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## hman (Nov 7, 2022)

Here's my welding cart.  I added a tank rack  with larger wheels to a Harbor Freight 4 drawer cart:
... Post #7 at https://www.hobby-machinist.com/thr...th-tool-chest-welding-cart.87830/#post-788031


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## General Zod (Nov 7, 2022)

erikmannie said:


> If you are welding .090” square tubing with 3/32” stick electrodes, what would you say is a good range for the gap in the fit-up?
> 
> I would obviously not bevel the .090”. I like some gap (at least a few thou) for this thickness. At any gap above .050”, I am *seriously* questioning my fit-up skills. .063” and up and I am unhappy with the situation.


I usually aim for zero-gap, but that doesn't always happen


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## Cadillac (Nov 7, 2022)

I would imagine something like this with a mountain bike rim and tire or similar. Having a heavy divider between the cylinder to strap them too is much better than chains. Mine has chains and allows the cylinder to flop around if not careful.


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## Just for fun (Nov 7, 2022)

Cadillac said:


> *Having a heavy divider between the cylinder to strap them too is much better than chains. Mine has chains and allows the cylinder to flop around if not careful.    -Snip-*



My cart is a modified hand truck, the tanks are secured with a chain.  To keep the tanks from banging together or just moving around, I wrapped a heavy rubber bungie cord around them, they don't move at all.  I was always going to make something nicer, but it has worked for the last 30 years.  So, my guess is that it will go down with the ship.


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## Aaron_W (Nov 7, 2022)

erikmannie said:


> If you guys have any ideas about the handle, a foot kicker or how I might chain the cart to the wall, I welcome any input.
> 
> I live extremely close to the San Andreas fault line, & my sweet mother-in-law lives directly above my shop, so we don’t want any lapses in safety.



I don't recall your outside layout, d you have a wooden fence close to your work area that you could put a heavy eyebolt into for chaining the cart? Or would it be possible to sink a post into the ground that you could chain it too? Think hitching post for a horse. Otherwise it will have to be attached to the wall of the house which may not be as desirable an option.


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## Firebrick43 (Nov 7, 2022)

erikmannie said:


> Since everybody has recommended large wheels, I will probably use 26” bicycle wheels. There is a bicycle recycling shop in town, & I’m sure that I can buy a pair of MTB wheels for very cheap.


I have thought about it, but can you change out the little stub axle for forks to use with an axle/nut?  I don't know enough about bicycles?


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## hman (Nov 8, 2022)

IIRC, the stub axles on bicycles include ball bearing races.  So they'd be difficult to duplicate/fabricate.  However, it might be possible to fabricate a suitably long spacer, internally threaded at both ends to accept the stub axles. Then the only issue would be the possibility of a stub axle bending or breaking under too heavy a load.


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## erikmannie (Nov 8, 2022)

Firebrick43 said:


> I have thought about it, but can you change out the little stub axle for forks to use with an axle/nut?  I don't know enough about bicycles?



I happen to have gone through bike school (UBC). A lot of people don’t even realize that there are bike schools.

I will fabricate one long axle, the ends of which will accept standard axle nuts.

The bearings are in the hubs of the bicycle MTB wheels that I will buy.

One good thing about bicycle parts is that they can be pretty affordable. Thank you, Taiwan!


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## erikmannie (Nov 8, 2022)

I am going to put a door in the front of this cart. I never want to be in the position of having to lift a gas cylinder 2-3’ off the ground.

I am soliciting ideas for hinges!

I am trying to finish another project that will only take me about another 6 days, but I need to get down the steel yard before the weekend to buy a lot of 1”, .090” wall mild steel square tubing.

I will not buy the 2 new cylinders until the cart is completely finished, although I am going to go down to the welding supply store (Matheson) to ask the diameters of the cylinders that they will sell me at that time.


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## erikmannie (Nov 8, 2022)

The door will be the same 1” square tubing that makes up the cart.

Since I don’t have a bandsaw, I am planning to miter the 45° angles on the knee mill. This will be the first time that I have cut with a tilted head.


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## Aaron_W (Nov 8, 2022)

erikmannie said:


> I am going to put a door in the front of this cart. I never want to be in the position of having to lift a gas cylinder 2-3’ off the ground.
> 
> I am soliciting ideas for hinges!
> 
> ...



I used large diameter pipe to hold the base of the tanks on my welding cart. What I found was regardless of capacity they are all more or less the same diameter within a 1/2" or so, height is the major change. There is a slight variation in size between steel vs aluminum bottles. I think 9" diameter was the generic measurement I used. 

I cut down some larger diameter (I think 10" maybe 12") thick wall pipe from the off cuts rack at my local metal supply on my cart, which I regret. I should have gone with a thinner wall pipe cut to length from a smaller diameter. The pipe I used does the job but added a lot of unnecessary weight and gives the tanks some slop. Since the cut offs are sold by weight I probably didn't even save much money.

I was told at the time most people are not happy with their first welding cart no matter how well they plan. You always find flaws you would do differently on the next go.


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## erikmannie (Nov 8, 2022)

I had been outside sanding when it was sprinkling, but once it started raining I went to the steelyard.

I bought 5 quantity 10’ lengths of 3/32” (.094”) wall, 1” square tubing, 3 hinges, & 2 hitch pins (to be used as a latch). The total for all this was $140 out the door.

At that point, my Dad gifted me 2 grates. I am not sure if I will include a small tool caddy & use the small grate, but the large grate will lay over the base of the dolly.

I am starting to think that I want to orient the cylinders in a fighter pilot configuration rather than side-to-side like you see in most O/A dollies. Every time I use this, I will pass through a pedestrian door. No need to make a wide dolly.


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## erikmannie (Nov 9, 2022)

So I have definitely decided to only use O/A processes (torch cut, gas weld and/or braze) to build this cart…because it is an O/A cart.

I would love to braze the whole thing, but some of the joints are not suited to brazing, in my opinion. I know that brazing fillet & lap joints is fine, but what do you guys think of brazing butt & edge joints? I do *not* like the idea because I almost always machine or grind down my butt & edge joints to flush.

I will definitely do the nicest work that I can, & leave the cart unfinished (i.e. no paint). I will use way oil (ideally Vactra #4) to protect it from corrosion. The cart will live inside, but be used outside only. I wouldn’t spend the money to clearcoat it.

At this point, I am inclined to gas weld the edge and butt joints, and braze the fillet and lap joints. The lap joints are on the hinges. It will probably end up looking a little odd having both gas welded & brazed joints, but the gas welded joints will be ground down to flush so nobody will see those joints.


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## erikmannie (Nov 9, 2022)

Here are today’s prices from my neighborhood Matheson (which has *stellar* customer service):

Customer owned 80 ft.³ oxygen cylinder, empty: $214,

80 ft.³ of oxygen: $37,

Customer owned 75 ft.³ acetylene cylinder, empty: $232,

75 ft.³ of acetylene: $71.

All of the above with California sales tax: $625.

You need an open pickup truck (i.e. no camper shell) to pick up the acetylene. I will have to borrow a friend’s truck.


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## WobblyHand (Nov 9, 2022)

erikmannie said:


> You need an open pickup truck (i.e. no camper shell) to pick up the acetylene. I will have to borrow a friend’s truck.


I'm not surprised about that.  The explosive limit range for acetylene is very wide.

_Lower explosive limit: 2.5%; upper explosive limit: 82%.  _From https://webwiser.nlm.nih.gov/substance?substanceId=35&catId=63
So even a little leak and a spark can cause a big bang.  Keep the bottle upright and chained, not on it's side.

Those bottle prices seem high, but everything is high these days.  Might want to shop around for empty new bottles.  Maybe you can do a little better.  Like an idiot, I lease my tanks, but at least I get to have decent sized ones.  Hate to run out in the middle of a job.


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## pontiac428 (Nov 9, 2022)

Please reconsider using way oil as a metal finish for your cart- just clear coat it instead.  The oil will get dirty and end up everywhere, and one thing you DO NOT WANT contaminating the pressure side of your O2 system is hydrocarbons.  I keep all forms of oil and grease away from my gas setups.  It is just as important as keeping chips off of your electronics.

I know that I am harsh about people making a big deal out of nothing, but this isn't nothing, it's your house, your shop, your tools, your family...


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## erikmannie (Nov 9, 2022)

pontiac428 said:


> Please reconsider using way oil as a metal finish for your cart- just clear coat it instead.  The oil will get dirty and end up everywhere, and one thing you DO NOT WANT contaminating the pressure side of your O2 system is hydrocarbons.  I keep all forms of oil and grease away from my gas setups.  It is just as important as keeping chips off of your electronics.
> 
> I know that I am harsh about people making a big deal out of nothing, but this isn't nothing, it's your house, your shop, your tools, your family...



*Such a great point*: oil near the compressed oxygen. I am surprised that I overlooked that.


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## tq60 (Nov 10, 2022)

You have a mill but no band saw and want to cut with gas, good.

Cut 1/8 long.

Get a end mill long enough to do full width of material in one pass.

Cut material.

Place in mill and square the ends.

Cut like pairs at same time so lengths can be same.

This does a few things.

Square ends with full thickness is target.

Cut a few coupons from the short ends of the lengths for practice.

This project is perfect for either MIG or puddle.

Mig would be better but you want to do gas so puddle it, braze is a mess.

Having the square full thickness ends means the joints will clamp tight and square.

Use a framing square to clamp to the material to assist.

Tack weld a few places to hold it.

Proper puddle will require just a bit of filler and when finished very little grinding to remove just the high spots.

Bondo when done then proper paint prep and good paint.

Place your axle such the wheels are just above ground, the cart will be plenty heavy to stand up.

Having the wheels not touching ground keeps them ROUND.

Only need 1/8 inch.

Make feet under so Only the feet touch, floors are not perfect and metal touching floor gets rusty.

Simple 1/4 nut welded on works.

Sent from my SM-G781V using Tapatalk


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## erikmannie (Nov 11, 2022)

tq60 said:


> You have a mill but no band saw and want to cut with gas, good.
> 
> Cut 1/8 long.
> 
> ...



Wow, that was countless helpful recommendations in one response!

I had planned on side milling the ends to length, but I would not have thought to do several equal lengths at once. I have a lot of long, large solid carbide endmills for this task.

Am I to understand that you recommend that I do *not* miter the corners to 45°? I don’t want to. Do you guys think it would be okay to forgo mitering the corners to 45°?

I am fine to gas weld the whole thing. My goal is to exceed 100% penetration by leaving a tiny gap in, say, a butt weld, & then welding it in such a manner as to have an excess of fill on the back of the seam. I do this because I almost always machine or grind the top of the weld down to flush.

For the fillet welds, this is a challenge for me with any processes other than brazing or stick. I will just have to do the best I can, as I would not take the time to file down the hard filler material to a nice radius (although I would come in with a round file to knock down the high points).

If I were to braze the fillet joints, the bronze is soft enough to file down the fillet with a round file. I don’t mind the mess of brazing, but I think it is not the best idea to have a weld seam that is part gas welded & part brazed.

This cart is definitely going to be clear coated. I like to challenge myself by having my work exposed for all to see. You can hide a lot of mistakes with paint and powder.


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## erikmannie (Nov 11, 2022)

I bought the hubs. They were only $20 each & look to be perfect for this application.




I will not use the supplied (probably galvanized butter) axles. Rather, I will fabricate a single long axle.

I made the phone call (Forrest Carver at Bath Cycle & Ski) to buy some *cheap* spokes, rims, tires and tubes, but I need to get the hub in my hands to make one more measurement in order to calculate the spoke length.

Fortunately, I have a wheel truing stand + spoke wrenches, & I have taken several bicycle wheel building classes. It will take me between 1-2 hours to build each wheel, & I will probably never have to mess with the wheels for the rest of my life (unless I break a spoke).










Presently, I am planning on using 26” tires. I could also choose from 16”, 20”, 24”, 27.5” or 29”. The 26” stuff is the most affordable.

I welcome any ideas on tire width & tread type. I can’t imagine that knobby tires would be called for. I *can* imagine that the more width, the better. I am leaning toward 4” wide tires with a thick street tread.


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## FOMOGO (Nov 12, 2022)

Not only dangerous, but being in a welding environment it would be filthy as soon as you started grinding, sanding, etc.. I used a hightemp, ceramic based engine clear-coat over a diluted gun bluing finish on my recent workbench project, and it seems like it will hold up well. Mike



erikmannie said:


> *Such a great point*: oil near the compressed oxygen. I am surprised that I overlooked that.


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## tq60 (Nov 12, 2022)

Regarding metering the joints ..

Personal choice, material allows for easier full penetration but now more filler needed.

With thin material this may not be needed.

This is why I suggested practice.

You have been doing so for other process, lesson learned here applies there.

Full thickness is also easier to clamp.

C-Clamp across the joint holds in perfect alignment.

Do not get in a hurry as it can warp if you try to complete a joint in one pass.

Sent from my SM-G781V using Tapatalk


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## erikmannie (Nov 12, 2022)

FOMOGO said:


> Not only dangerous, but being in a welding environment it would be filthy as soon as you started grinding, sanding, etc.. I used a hightemp, ceramic based engine clear-coat over a diluted gun bluing finish on my recent workbench project, and it seems like it will hold up well. Mike



I would be interested to know the brand of gun bluing finish, how much you dilute it, & may I assume that the aforementioned clear-coat is rattle can?


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## erikmannie (Nov 12, 2022)

tq60 said:


> Regarding metering the joints ..
> 
> Personal choice, material allows for easier full penetration but now more filler needed.
> 
> ...



I really need to buy some C-clamps large enough for this task. I have none now.

My last gas welding project was converting a bed to a bench: 100+ year old mild steel that was 5-15% corroded, .050”-ish wall round tubing painted with (probably) lead-based white paint. What a pleasure it will be for me to weld on clean new 3/32” steel!

Thanks for reminding me to practice right before the project. I can practice butt & fillet welds on the leftover square tubing, & then seeing how penetration was achieved on these practice welds.


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## erikmannie (Nov 12, 2022)

I realized that I already have bicycle tires & tubes here. The tires are 26” diameter & 5.25” wide knobbies. Obviously, I will use these since they are already here  & paid for.

Now I just need 80mm rims. One idea is to buy rims with cutouts in them, & use 1 green & 1 red rim strip since it is an O/A cart.

Like this:




If there is a concern about spatter getting on there & burning the tube, one can use colored tape instead of a proper rim strip. I’m sure they make colored, high temp tape. Does anybody have a safety concern about using a rim strip? They are thin but tough. They also happen to be very inexpensive.


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## erikmannie (Nov 12, 2022)

On second thought, it is better to have aluminum there than a rim strip. I will just use solid aluminum rims.


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## FOMOGO (Nov 12, 2022)

I used Birchwood Casey Super Blue. I got the large 32oz bottle because I plan on using it on other large projects, but it goes a long way so you might want a smaller bottle. How much you dilute it depends on the look you want. I would use it straight on a test piece, and dilute to taste. You want to get rid of all the mill scale first, and neutralize after application. The clear is made by Dupli-Color, and is rattle can. Mike



erikmannie said:


> I would be interested to know the brand of gun bluing finish, how much you dilute it, & may I assume that the aforementioned clear-coat is rattle can?





			https://www.amazon.com/Birchwood-Casey-Super-Liquid-Ounce/dp/B00162QGV8/ref=sr_1_14?crid=1GFKYUAZY1S4F&keywords=super+blue+gun+bluing&qid=1668278390&sprefix=Su%5Ber+Blue%2Caps%2C192&sr=8-14


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## tq60 (Nov 12, 2022)

You only need a c clamp big enough to clamp the sides of the tube together,

Imagine the line of the interface between the 2 tubes.

Place c clamp so the line splits the faces of the clamp.

For clamping the parts together get some BAR clamps.

These are inexpensive and in assorted lengths.

Sent from my SM-G781V using Tapatalk


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## erikmannie (Nov 13, 2022)

I bought solid (i.e. flat proof) tires. I chose red tires to remind myself to work safely. They had a 56% off sale so it was $83.98 for both tires including tax + shipping. I have installed these on a rim; it is frustrating & time consuming.












						Razorblade: 26"x1.75"
					

Tannus airless bicycle tires are puncture proof bike tires that don't go flat.  Bike tires that are solid and made out of a lightweight foam that will last long




					tannusamerica.com


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## erikmannie (Nov 13, 2022)

I also bought red rims. I have to wait until I have rim + hub in hand before I take measurements to determine the spoke length.

With the fighter jet configuration of the cylinders & the red tires, this cart is going to look ridiculous.


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