Thats really nice !!!!!
Your pic has my mind a buzzin with anticipation as to how this would look in my back yard...

Great job on the tutorial! Nice to have so many clear photos of all, and especially how to convert the sliding door to a hinged one. I have the 10x12 HFGH which is taller, but if I had the 6x8 I would definitely have raised it just as you have.

Applying the 6 ml UV film is an interesting solution to the panel deterioration problem. Very neatly done, seems like it should make a big difference. I have used foil HVAC tape to seal the ends of my panels, but in my heat it seems to give up the ghost at about the two year mark. If you have any problems with that, I'm now using clear duct tape instead, and I'll bet that would work to adhere the film too. So far my clear duct tape has lasted over three years, and doesn't look too bad.

Super good idea to strengthen the structure by anchoring benches to the frame.

I kind of like the sliding HFGH doors (note I said like, not love) because I can open the doors up anywhere from a crack to fully open, depending on the temperature and winds. But you're completely right, lots of folks do not like them, especially if they live some place where ice can accumulate in the track and freeze them shut. Sometimes, when I have to vacuum the desert sand out of my door track, I think about converting to hinged.

Okay, now just add a screw or two to each panel, into the frame, so I won't worry about your great greenhouse in a bad wind! ;-)

Here is a clickable link to your instructables post, so folks will be sure to check out your good tutorial:
Building and Improving the Harbor Freight 6x8 Greenhouse

Thanks for the comments mudhouse. I'm a HUGE fan of the HF build you have on your web site and for all the aid you've given to green house builders. In fact it was your build that encouraged me to tackle the HF kit in the first place. So I put much credence in your observations, particularly the use of clear duct tape as an alternative to the foil tape.

dewey1945, it's just a shame that sometimes we can only learn what works by giving it a go...and then waiting (quite a while) to see the final results! I'm glad you've posted here with your solution of applying the film, and I hope you'll continue to do so and let us know how everything goes.

That's the strength of these forums...throwing out new ideas and posting back so others can benefit. Most of the ideas in my blog came from other GardenWeb HFGH owners.

I'm happy to see a post that deals specifically with the 6x8 too, as there are some differences, and my blog may not help folks with some 6x8 questions.

Thanks so much for your good help here. Looking forward to more updates!

I really like what you've done! A friend who has a 10x12 is always reminding me what a great deal these are (especially on sale and with coupons), but I don't have room for a 10x12 or even a 6x8.

Right now I have a self-built PVC film-covered greenhouse which fits in the space I do have (6x6). It's functional, but could be nicer looking or even better designed (waiting for the film to degrade before instituting structural changes).

But I've wondered...can the 6x8 HF greenhouse be assembled to be 6x6? It looks like the long dimension might be divided into 2 ft sections? Would it be practical (possible?) to cut down the long horizontal pieces so that a section can be omitted, resulting (maybe) in a 6x6?

I'm sure it seems incredible to anyone that I would want to do that, but I'm resigned to my space limitations and I do use what greenhouse I have to grow pineapples, mangoes (not fruit there yet...) and other things. Just wondering about something like the HF and the possibilities.

I've never seen it done (cutting two feet off the end of the greenhouse) but I think it would be possible if you took a lot of care with your measurements and cuts. At a minimum I would recommend a metal chop saw or band saw for making the cuts nice and square.

Just saw yesterday that the 6x8 HFGH will be $199 on March 8,9,10. They said I couldn't use a 20% off coupon on this during that time though.

I just received a mailing from HF with a coupon for the 10x12 for $599. (limit 4) You can't use the % off coupons with this price.

I have a 6 x 8 HFGH and love it. I've read some of the forums regarding improving and streghtening them. I am looking to hook a second one on to the back of my present one. I think it was mudhouse who hooked 2 of the 10 x 12's back to back, but has anyone done it with the 6 x 8? I don't have the room for a 10 x 12, and it's far to windy here. we live fight on the Strait of Juan de Fuca across from canada, and we get hurricane force winds here. Any advice on hooking 2 6 x 8's together would be most welcome. Thanks

Hello saturn3600,
Milwdave joined two 6x8 Harbor Freight greenhouses. I don't recall seeing posts from him here recently, but here's a link to his photos:
Greenhouse Construction by Milwdave

I only have one 10x12 Harbor Freight greenhouse (no room for two!) YouâÂÂre probably remembering a thread I posted a few years back for another Garden Web member, Funnylady. (She was having some trouble posting pictures, so she let me set up the thread for her.) Her greenhouses are 10x12, but the photos are very helpful. She has just added a new post at the end of this thread, updating us that she now has three Harbor Freight greenhouses! So, you could pop in there and say hello:
Two Harbor Freight 10x12 Greenhouses Joined Together

Also, Rosepedal joined two 10x12 greenhouses together, and there are some photos at the end of this thread showing the new one being added to the back of her existing greenhouse: WeâÂÂre Going Saturday

I hope you will post some pics here if you join a second 6x8 to your structure.

Well shoot, sorry saturn, I had my threads mixed up. Funnylady (the apparent queen of joining Harbor Freight greenhouses together, if she now has three) has just posted at the end of Rosepedal's thread, last link listed in my post above. Not her own thread (second link.)

I can't keep up...!

Dewey1945, Nice job! I have been looking over your build along with mudhouse's. Just one question, were you worried about putting the aluminum frame on the treated lumber?

eastpenna,

I didn't worry about the aluminum on treated lumber. In fact, the HF building manual specifically calls for putting the framework directly on treated material. If you are concerned, you could lay a strip of foundation foam (it comes in rolls and is used for setting joists on top of concrete foundations...I think it's about 1/4" thick) between the lumber and the aluminum.

dewey1945 with all that hard work you put into your greenhouse I hate the fact that your bottom rail is going to disintegrate in a few years. Is there someway you could lift the bottom rail and put a barrier between the pressure treated and the aluminum frame?
I own a Sunroom company and trust me when I tell you the pressure treated is going to eat the aluminum. I have seen it many,many times. All the building codes have been changed since 2004.
As of January 2004 there was a change in the chemical preserves used for pressure treated lumber. The new pressure treated lumber is preserved with Alkaline Copper Quaternary which is very corrosive to aluminum.
The Harbor Freight Manual was written back in 2002 so you cannot go off of that.

hartford,

Thanks for posting up that info. This seems to be be something all hobbyists should be alerted to since almost every "how-to" on the web is done this way. Question, are the chemicals corrosive to all metals (such as galvanized steel) or just aluminum? It wouldn't be too difficult to slip a narrow strip of galvanized material between the base and the frame.

The building code lists Hot-dip galvanized or stainless steel. We use galvanized lags for our sunrooms. Could you get a piece of vinyl underneath the track? We use vinyl coil stock to cover the outside of the pressure treated decks we put the Sunrooms on.

Yes, I could slip a strip of vinyl under the track without too much difficulty. I have some UV treated upholstery vinyl...used for upholstering boats. Think that work?

That should be fine.
Thanks for posting your step by step instructions on modifying the HFGH.
I just did the 2x12 foundation today for mine. The weather finally is starting to break up here in PA. :)

Nice work hartford.

Dewey, how do you like the wire racks for your bench? I am just about ready to add my benches and was debating on either wire shelves or just using 2 x 2's, (like you have for your supports), spaced 3/4" to 1" apart.

Hartford, I used some 1" x 2" cedar boards on top of my pressure treated base to separate the aluminum from the PT lumber.

eastpenna,

Good question. Like most things I guess me review of the wire shelves would be "mixed".

The good - wire shelving is stable (when properly supported), allows a decent amount of sunlight to pass through to lower shelves, works well for watering (overflow), and it does look very nice.

The not so good - wire shelving can be a problem if you use lots of small cups (I often use the little, 3 to 7 oz, dixie type cups) for germination and seedlings. If they are not set in a near perfect position, they tend to tip over with the slightest of touch or when then they get hit with the watering stream. This problem, however, might also be true for the 2x2 system you are looking at as an alternative. The only way around it that I can see is to use solid board shelves, which will cut off light and be a problem with watering overflow. Or you could not use the small cups on these racks. In my case, I use the small cups and just learn to keep my swearing well muffled whenever they get tipped over.

Maybe some other folks have come up with better options.

I ended up going with the wire shelves, however I used the 20" deep close mesh ones, they have 1/2" spacing. Then I just added a 2x4 on the back side near the wall as my shelf supports were 24" deep. It ends up being level with the wire shelves that are sitting on top of some 2x2 pressure treated lumber.

Thanks for your help!!

Nicely done eastpenna. And good looking little electrical run there in the background. The floor looks great. Is that tamped gravel/sand?

Thanks dewey, here is a shot of the electric, I only installed two outlets as I am not sure what else I will need.

The floor is actually the concrete patio next to my house.