Posts: 4,004
Threads: 0
Joined: Apr 2002
You might consider something like I did in the attached sketch. You aren't relying on the weight of the DP being supported by only part of the thickness of the sides and there's no need to double up the sides. You can use your poplar to make rails to go under the top
sort of like a torsion box. I've drawn that frame with 3/4 in. x 2 in. parts. The back is let into rabbets on the sides, top, and bottom. An optional rail could be added at the front between the sides.
Get the casters before you settle on the actual height of the case. 4 in. casters generally implies the wheels are 4 in. dia. which requires the overall height of the casters to be more than 4 in.
![[Image: 50169193718_da98cddc8c.jpg]](https://live.staticflickr.com/65535/50169193718_da98cddc8c.jpg)
Posts: 169
Threads: 0
Joined: Oct 2019
Location: Monmouth County NJ
07-30-2020, 09:36 AM
(This post was last modified: 07-30-2020, 09:37 AM by briman87.)
(07-30-2020, 08:11 AM)DaveR1 Wrote: You might consider something like I did in the attached sketch. You aren't relying on the weight of the DP being supported by only part of the thickness of the sides and there's no need to double up the sides. You can use your poplar to make rails to go under the top sort of like a torsion box. I've drawn that frame with 3/4 in. x 2 in. parts. The back is let into rabbets on the sides, top, and bottom. An optional rail could be added at the front between the sides.
Get the casters before you settle on the actual height of the case. 4 in. casters generally implies the wheels are 4 in. dia. which requires the overall height of the casters to be more than 4 in.
Thanks for the illustration. I thought about something like that as well. Also the stretcher could be used as a drawer separator and do the runners on the edges for a draw. I am fine with the box being slightly taller or shorter as the DP is currently on a table at my work that is 34 inches tall. The total height of the drill from the table to the oil spout it is 40 inches with the belt being at 32 inches in its current speed. I can always drop down to 3 inches cause I just looked it up that the 3 inch wheels have a total height of 6.9 they support 175lbs a piece so that would be 700lbs total. One thing that I do not have is a nail gun it is on my list to get along with a compresser. I have plenty of screws and finishing nails at my disposal.
Posts: 4,004
Threads: 0
Joined: Apr 2002
Personally I wouldn't worry about not having a nail gun. I'd assemble it with screws and glue. Screws into the edge of MDF aren't especially strong in tension but with the case as I've sketched it, there really isn't anywhere that screws would be in tension. Most of this will be in compression. You don't need all that many screws, either. Glue the top to the frame underneath it and it'll be plenty strong.
Put the casters directly under the sides of the case. Make the bottom wide enough so there's room on the outside of the case sides for the mounting bolts. Short carriage bolts inserted from the top will make a nice, clean, low profile attachment.
Posts: 2,382
Threads: 0
Joined: Dec 2011
07-30-2020, 09:56 AM
(This post was last modified: 07-30-2020, 09:58 AM by Handplanesandmore.)
DaveR1 provides an excellent sketch of a construction that can stand the weight of a bull. Don't use double MDF sheets all around as it's both a waste of material and putting on unnecessary weight. Double MDF strips only where they're needed.
Use mdf screws (Homedepot eg) or untapered metal screws, not wood screws in addition to glue. A back is a must to add rigidity and to prevent racking. Unless your shop is constantly flooded (with the risk of the cart being in contact with water), you need not worry about humidity or stuff like that.
Simon
Posts: 169
Threads: 0
Joined: Oct 2019
Location: Monmouth County NJ
I
(07-30-2020, 09:56 AM)Handplanesandmore Wrote: DaveR1 provides an excellent sketch of a construction that can stand the weight of a bull. Don't use double MDF sheets all around as it's both a waste of material and putting on unnecessary weight. Double MDF strips only where they're needed.
Use mdf screws (Homedepot eg) or untapered metal screws, not wood screws in addition to glue. A back is a must to add rigidity and to prevent racking. Unless your shop is constantly flooded (with the risk of the cart being in contact with water), you need not worry about humidity or stuff like that.
Simon
I had had the shop area flood twice in the 5 months I have lived there as it is in the basement. The first time was because the gutter had separated from the house and there was a low spot in the front flower bed. We have since filled the whole area with about 5-7 inches of top soil and have graded it away from the foundation. The second time the water came in from the back where there was a rusted hole in the window well which I have since filled with the great stuff foam. Both times the water has never been higher than maybe an inch so with the caster at 3 or 4 inches it should never get that high and if so we will need the Ark.
We do have a dehumidifier running pretty much 24/7 and dump it twice a day the humidity on the dehumidifier is set for 40% which when it fills up and while I'm at work gets up to maybe 50-60%.
Posts: 589
Threads: 0
Joined: Jan 2017
Location: Marina del Rey
I would not use MDF. Use MDO or plywood instead. Casters will make this top-heavy machine tippy, so place them as far apart as possible.
Wood is good.
Posts: 2,382
Threads: 0
Joined: Dec 2011
07-30-2020, 01:02 PM
(This post was last modified: 07-30-2020, 01:02 PM by Handplanesandmore.)
(07-30-2020, 12:56 PM)ez-duzit Wrote: Casters will make this top-heavy machine tippy, so place them as far apart as possible.
If footprint is a concern. the other alternative is to keep the center of gravity for this kind of build as low as practicable regardless of what wood is used.
Simon
Posts: 14,851
Threads: 10
Joined: Jan 2010
Location: southeastern VA
(07-30-2020, 09:56 AM)Handplanesandmore Wrote: DaveR1 provides an excellent sketch of a construction that can stand the weight of a bull. Don't use double MDF sheets all around as it's both a waste of material and putting on unnecessary weight. Double MDF strips only where they're needed.
Use mdf screws (Homedepot eg) or untapered metal screws, not wood screws in addition to glue. A back is a must to add rigidity and to prevent racking. Unless your shop is constantly flooded (with the risk of the cart being in contact with water), you need not worry about humidity or stuff like that.
Simon
Probably not an issue in this basement, but...
If the temperature cycles enough for the DP to condense moisture, then there needs to be a good barrier between that condensed water and the MDF. That seal also better include the holes that the bolts go through for mounting the base to the cart.
We made the mistake of leaving an empty metal bucket sitting on raw MDF. We got a spreading area away from the ring around the base of the bucket where the MDF swole up and started to come apart.
"the most important safety feature on any tool is the one between your ears." - Ken Vick
A wish for you all: May you keep buying green bananas.
Posts: 3,545
Threads: 1
Joined: May 2004
Location: Wisconsin
Has anyone encountered moisture resistant MDF here in the US? Peter Millard on YouTube uses it all the time in the UK, but I wonder why it's not as common here.
Posts: 2,078
Threads: 1
Joined: Feb 2009
Location: Mechanicsville, Md
It's used quite a bit in commercial millwork. The shop I worked in Southern Md used it and it's required on the project in Pa I'm on. In my opinion, better than regular MDF
I no longer build museums but don't want to change my name. My new job is a lot less stressful. Life is much better.
Garry
